| /* Functions related to invoking -*- C++ -*- methods and overloaded functions. |
| Copyright (C) 1987-2020 Free Software Foundation, Inc. |
| Contributed by Michael Tiemann (tiemann@cygnus.com) and |
| modified by Brendan Kehoe (brendan@cygnus.com). |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3, or (at your option) |
| any later version. |
| |
| GCC is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| |
| /* High-level class interface. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "target.h" |
| #include "cp-tree.h" |
| #include "timevar.h" |
| #include "stringpool.h" |
| #include "cgraph.h" |
| #include "stor-layout.h" |
| #include "trans-mem.h" |
| #include "flags.h" |
| #include "toplev.h" |
| #include "intl.h" |
| #include "convert.h" |
| #include "langhooks.h" |
| #include "c-family/c-objc.h" |
| #include "internal-fn.h" |
| #include "stringpool.h" |
| #include "attribs.h" |
| #include "gcc-rich-location.h" |
| |
| /* The various kinds of conversion. */ |
| |
| enum conversion_kind { |
| ck_identity, |
| ck_lvalue, |
| ck_fnptr, |
| ck_qual, |
| ck_std, |
| ck_ptr, |
| ck_pmem, |
| ck_base, |
| ck_ref_bind, |
| ck_user, |
| ck_ambig, |
| ck_list, |
| ck_aggr, |
| ck_rvalue |
| }; |
| |
| /* The rank of the conversion. Order of the enumerals matters; better |
| conversions should come earlier in the list. */ |
| |
| enum conversion_rank { |
| cr_identity, |
| cr_exact, |
| cr_promotion, |
| cr_std, |
| cr_pbool, |
| cr_user, |
| cr_ellipsis, |
| cr_bad |
| }; |
| |
| /* An implicit conversion sequence, in the sense of [over.best.ics]. |
| The first conversion to be performed is at the end of the chain. |
| That conversion is always a cr_identity conversion. */ |
| |
| struct conversion { |
| /* The kind of conversion represented by this step. */ |
| conversion_kind kind; |
| /* The rank of this conversion. */ |
| conversion_rank rank; |
| BOOL_BITFIELD user_conv_p : 1; |
| BOOL_BITFIELD ellipsis_p : 1; |
| BOOL_BITFIELD this_p : 1; |
| /* True if this conversion would be permitted with a bending of |
| language standards, e.g. disregarding pointer qualifiers or |
| converting integers to pointers. */ |
| BOOL_BITFIELD bad_p : 1; |
| /* If KIND is ck_ref_bind or ck_base, true to indicate that a |
| temporary should be created to hold the result of the |
| conversion. If KIND is ck_ambig or ck_user, true means force |
| copy-initialization. */ |
| BOOL_BITFIELD need_temporary_p : 1; |
| /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion |
| from a pointer-to-derived to pointer-to-base is being performed. */ |
| BOOL_BITFIELD base_p : 1; |
| /* If KIND is ck_ref_bind, true when either an lvalue reference is |
| being bound to an lvalue expression or an rvalue reference is |
| being bound to an rvalue expression. If KIND is ck_rvalue or ck_base, |
| true when we are treating an lvalue as an rvalue (12.8p33). If |
| ck_identity, we will be binding a reference directly or decaying to |
| a pointer. */ |
| BOOL_BITFIELD rvaluedness_matches_p: 1; |
| BOOL_BITFIELD check_narrowing: 1; |
| /* Whether check_narrowing should only check TREE_CONSTANTs; used |
| in build_converted_constant_expr. */ |
| BOOL_BITFIELD check_narrowing_const_only: 1; |
| /* True if this conversion is taking place in a copy-initialization context |
| and we should only consider converting constructors. Only set in |
| ck_base and ck_rvalue. */ |
| BOOL_BITFIELD copy_init_p : 1; |
| /* The type of the expression resulting from the conversion. */ |
| tree type; |
| union { |
| /* The next conversion in the chain. Since the conversions are |
| arranged from outermost to innermost, the NEXT conversion will |
| actually be performed before this conversion. This variant is |
| used only when KIND is neither ck_identity, ck_aggr, ck_ambig nor |
| ck_list. Please use the next_conversion function instead |
| of using this field directly. */ |
| conversion *next; |
| /* The expression at the beginning of the conversion chain. This |
| variant is used only if KIND is ck_identity, ck_aggr, or ck_ambig. |
| You can use conv_get_original_expr to get this expression. */ |
| tree expr; |
| /* The array of conversions for an initializer_list, so this |
| variant is used only when KIN D is ck_list. */ |
| conversion **list; |
| } u; |
| /* The function candidate corresponding to this conversion |
| sequence. This field is only used if KIND is ck_user. */ |
| struct z_candidate *cand; |
| }; |
| |
| #define CONVERSION_RANK(NODE) \ |
| ((NODE)->bad_p ? cr_bad \ |
| : (NODE)->ellipsis_p ? cr_ellipsis \ |
| : (NODE)->user_conv_p ? cr_user \ |
| : (NODE)->rank) |
| |
| #define BAD_CONVERSION_RANK(NODE) \ |
| ((NODE)->ellipsis_p ? cr_ellipsis \ |
| : (NODE)->user_conv_p ? cr_user \ |
| : (NODE)->rank) |
| |
| static struct obstack conversion_obstack; |
| static bool conversion_obstack_initialized; |
| struct rejection_reason; |
| |
| static struct z_candidate * tourney (struct z_candidate *, tsubst_flags_t); |
| static int equal_functions (tree, tree); |
| static int joust (struct z_candidate *, struct z_candidate *, bool, |
| tsubst_flags_t); |
| static int compare_ics (conversion *, conversion *); |
| static void maybe_warn_class_memaccess (location_t, tree, |
| const vec<tree, va_gc> *); |
| static tree build_over_call (struct z_candidate *, int, tsubst_flags_t); |
| #define convert_like(CONV, EXPR, COMPLAIN) \ |
| convert_like_real ((CONV), (EXPR), NULL_TREE, 0, \ |
| /*issue_conversion_warnings=*/true, \ |
| /*c_cast_p=*/false, (COMPLAIN)) |
| #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \ |
| convert_like_real ((CONV), (EXPR), (FN), (ARGNO), \ |
| /*issue_conversion_warnings=*/true, \ |
| /*c_cast_p=*/false, (COMPLAIN)) |
| static tree convert_like_real (conversion *, tree, tree, int, bool, |
| bool, tsubst_flags_t); |
| static tree convert_like_real_1 (conversion *, tree, tree, int, bool, |
| bool, tsubst_flags_t); |
| static void op_error (const op_location_t &, enum tree_code, enum tree_code, |
| tree, tree, tree, bool); |
| static struct z_candidate *build_user_type_conversion_1 (tree, tree, int, |
| tsubst_flags_t); |
| static void print_z_candidate (location_t, const char *, struct z_candidate *); |
| static void print_z_candidates (location_t, struct z_candidate *); |
| static tree build_this (tree); |
| static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *); |
| static bool any_strictly_viable (struct z_candidate *); |
| static struct z_candidate *add_template_candidate |
| (struct z_candidate **, tree, tree, tree, tree, const vec<tree, va_gc> *, |
| tree, tree, tree, int, unification_kind_t, tsubst_flags_t); |
| static struct z_candidate *add_template_candidate_real |
| (struct z_candidate **, tree, tree, tree, tree, const vec<tree, va_gc> *, |
| tree, tree, tree, int, tree, unification_kind_t, tsubst_flags_t); |
| static bool is_complete (tree); |
| static struct z_candidate *add_conv_candidate |
| (struct z_candidate **, tree, tree, const vec<tree, va_gc> *, tree, |
| tree, tsubst_flags_t); |
| static struct z_candidate *add_function_candidate |
| (struct z_candidate **, tree, tree, tree, const vec<tree, va_gc> *, tree, |
| tree, int, conversion**, tsubst_flags_t); |
| static conversion *implicit_conversion (tree, tree, tree, bool, int, |
| tsubst_flags_t); |
| static conversion *reference_binding (tree, tree, tree, bool, int, |
| tsubst_flags_t); |
| static conversion *build_conv (conversion_kind, tree, conversion *); |
| static conversion *build_list_conv (tree, tree, int, tsubst_flags_t); |
| static conversion *next_conversion (conversion *); |
| static bool is_subseq (conversion *, conversion *); |
| static conversion *maybe_handle_ref_bind (conversion **); |
| static void maybe_handle_implicit_object (conversion **); |
| static struct z_candidate *add_candidate |
| (struct z_candidate **, tree, tree, const vec<tree, va_gc> *, size_t, |
| conversion **, tree, tree, int, struct rejection_reason *, int); |
| static tree source_type (conversion *); |
| static void add_warning (struct z_candidate *, struct z_candidate *); |
| static conversion *direct_reference_binding (tree, conversion *); |
| static bool promoted_arithmetic_type_p (tree); |
| static conversion *conditional_conversion (tree, tree, tsubst_flags_t); |
| static char *name_as_c_string (tree, tree, bool *); |
| static tree prep_operand (tree); |
| static void add_candidates (tree, tree, const vec<tree, va_gc> *, tree, tree, |
| bool, tree, tree, int, struct z_candidate **, |
| tsubst_flags_t); |
| static conversion *merge_conversion_sequences (conversion *, conversion *); |
| static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t); |
| static conversion *build_identity_conv (tree, tree); |
| static inline bool conv_binds_to_array_of_unknown_bound (conversion *); |
| static tree prevent_lifetime_extension (tree); |
| |
| /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE. |
| NAME can take many forms... */ |
| |
| bool |
| check_dtor_name (tree basetype, tree name) |
| { |
| /* Just accept something we've already complained about. */ |
| if (name == error_mark_node) |
| return true; |
| |
| if (TREE_CODE (name) == TYPE_DECL) |
| name = TREE_TYPE (name); |
| else if (TYPE_P (name)) |
| /* OK */; |
| else if (identifier_p (name)) |
| { |
| if ((MAYBE_CLASS_TYPE_P (basetype) |
| || TREE_CODE (basetype) == ENUMERAL_TYPE) |
| && name == constructor_name (basetype)) |
| return true; |
| else |
| name = get_type_value (name); |
| } |
| else |
| { |
| /* In the case of: |
| |
| template <class T> struct S { ~S(); }; |
| int i; |
| i.~S(); |
| |
| NAME will be a class template. */ |
| gcc_assert (DECL_CLASS_TEMPLATE_P (name)); |
| return false; |
| } |
| |
| if (!name || name == error_mark_node) |
| return false; |
| return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name)); |
| } |
| |
| /* We want the address of a function or method. We avoid creating a |
| pointer-to-member function. */ |
| |
| tree |
| build_addr_func (tree function, tsubst_flags_t complain) |
| { |
| tree type = TREE_TYPE (function); |
| |
| /* We have to do these by hand to avoid real pointer to member |
| functions. */ |
| if (TREE_CODE (type) == METHOD_TYPE) |
| { |
| if (TREE_CODE (function) == OFFSET_REF) |
| { |
| tree object = build_address (TREE_OPERAND (function, 0)); |
| return get_member_function_from_ptrfunc (&object, |
| TREE_OPERAND (function, 1), |
| complain); |
| } |
| function = build_address (function); |
| } |
| else if (TREE_CODE (function) == FUNCTION_DECL |
| && DECL_IMMEDIATE_FUNCTION_P (function)) |
| function = build_address (function); |
| else |
| function = decay_conversion (function, complain, /*reject_builtin=*/false); |
| |
| return function; |
| } |
| |
| /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or |
| POINTER_TYPE to those. Note, pointer to member function types |
| (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are |
| two variants. build_call_a is the primitive taking an array of |
| arguments, while build_call_n is a wrapper that handles varargs. */ |
| |
| tree |
| build_call_n (tree function, int n, ...) |
| { |
| if (n == 0) |
| return build_call_a (function, 0, NULL); |
| else |
| { |
| tree *argarray = XALLOCAVEC (tree, n); |
| va_list ap; |
| int i; |
| |
| va_start (ap, n); |
| for (i = 0; i < n; i++) |
| argarray[i] = va_arg (ap, tree); |
| va_end (ap); |
| return build_call_a (function, n, argarray); |
| } |
| } |
| |
| /* Update various flags in cfun and the call itself based on what is being |
| called. Split out of build_call_a so that bot_manip can use it too. */ |
| |
| void |
| set_flags_from_callee (tree call) |
| { |
| /* Handle both CALL_EXPRs and AGGR_INIT_EXPRs. */ |
| tree decl = cp_get_callee_fndecl_nofold (call); |
| |
| /* We check both the decl and the type; a function may be known not to |
| throw without being declared throw(). */ |
| bool nothrow = decl && TREE_NOTHROW (decl); |
| tree callee = cp_get_callee (call); |
| if (callee) |
| nothrow |= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (callee))); |
| else if (TREE_CODE (call) == CALL_EXPR |
| && internal_fn_flags (CALL_EXPR_IFN (call)) & ECF_NOTHROW) |
| nothrow = true; |
| |
| if (cfun && cp_function_chain && !cp_unevaluated_operand) |
| { |
| if (!nothrow && at_function_scope_p ()) |
| cp_function_chain->can_throw = 1; |
| |
| if (decl && TREE_THIS_VOLATILE (decl)) |
| current_function_returns_abnormally = 1; |
| } |
| |
| TREE_NOTHROW (call) = nothrow; |
| } |
| |
| tree |
| build_call_a (tree function, int n, tree *argarray) |
| { |
| tree decl; |
| tree result_type; |
| tree fntype; |
| int i; |
| |
| function = build_addr_func (function, tf_warning_or_error); |
| |
| gcc_assert (TYPE_PTR_P (TREE_TYPE (function))); |
| fntype = TREE_TYPE (TREE_TYPE (function)); |
| gcc_assert (FUNC_OR_METHOD_TYPE_P (fntype)); |
| result_type = TREE_TYPE (fntype); |
| /* An rvalue has no cv-qualifiers. */ |
| if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type)) |
| result_type = cv_unqualified (result_type); |
| |
| function = build_call_array_loc (input_location, |
| result_type, function, n, argarray); |
| set_flags_from_callee (function); |
| |
| decl = get_callee_fndecl (function); |
| |
| if (decl && !TREE_USED (decl)) |
| { |
| /* We invoke build_call directly for several library |
| functions. These may have been declared normally if |
| we're building libgcc, so we can't just check |
| DECL_ARTIFICIAL. */ |
| gcc_assert (DECL_ARTIFICIAL (decl) |
| || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)), |
| "__", 2)); |
| mark_used (decl); |
| } |
| |
| require_complete_eh_spec_types (fntype, decl); |
| |
| TREE_HAS_CONSTRUCTOR (function) = (decl && DECL_CONSTRUCTOR_P (decl)); |
| |
| /* Don't pass empty class objects by value. This is useful |
| for tags in STL, which are used to control overload resolution. |
| We don't need to handle other cases of copying empty classes. */ |
| if (!decl || !fndecl_built_in_p (decl)) |
| for (i = 0; i < n; i++) |
| { |
| tree arg = CALL_EXPR_ARG (function, i); |
| if (is_empty_class (TREE_TYPE (arg)) |
| && simple_empty_class_p (TREE_TYPE (arg), arg, INIT_EXPR)) |
| { |
| while (TREE_CODE (arg) == TARGET_EXPR) |
| /* We're disconnecting the initializer from its target, |
| don't create a temporary. */ |
| arg = TARGET_EXPR_INITIAL (arg); |
| tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (arg)); |
| arg = build2 (COMPOUND_EXPR, TREE_TYPE (t), arg, t); |
| CALL_EXPR_ARG (function, i) = arg; |
| } |
| } |
| |
| return function; |
| } |
| |
| /* New overloading code. */ |
| |
| struct z_candidate; |
| |
| struct candidate_warning { |
| z_candidate *loser; |
| candidate_warning *next; |
| }; |
| |
| /* Information for providing diagnostics about why overloading failed. */ |
| |
| enum rejection_reason_code { |
| rr_none, |
| rr_arity, |
| rr_explicit_conversion, |
| rr_template_conversion, |
| rr_arg_conversion, |
| rr_bad_arg_conversion, |
| rr_template_unification, |
| rr_invalid_copy, |
| rr_inherited_ctor, |
| rr_constraint_failure |
| }; |
| |
| struct conversion_info { |
| /* The index of the argument, 0-based. */ |
| int n_arg; |
| /* The actual argument or its type. */ |
| tree from; |
| /* The type of the parameter. */ |
| tree to_type; |
| /* The location of the argument. */ |
| location_t loc; |
| }; |
| |
| struct rejection_reason { |
| enum rejection_reason_code code; |
| union { |
| /* Information about an arity mismatch. */ |
| struct { |
| /* The expected number of arguments. */ |
| int expected; |
| /* The actual number of arguments in the call. */ |
| int actual; |
| /* Whether the call was a varargs call. */ |
| bool call_varargs_p; |
| } arity; |
| /* Information about an argument conversion mismatch. */ |
| struct conversion_info conversion; |
| /* Same, but for bad argument conversions. */ |
| struct conversion_info bad_conversion; |
| /* Information about template unification failures. These are the |
| parameters passed to fn_type_unification. */ |
| struct { |
| tree tmpl; |
| tree explicit_targs; |
| int num_targs; |
| const tree *args; |
| unsigned int nargs; |
| tree return_type; |
| unification_kind_t strict; |
| int flags; |
| } template_unification; |
| /* Information about template instantiation failures. These are the |
| parameters passed to instantiate_template. */ |
| struct { |
| tree tmpl; |
| tree targs; |
| } template_instantiation; |
| } u; |
| }; |
| |
| struct z_candidate { |
| /* The FUNCTION_DECL that will be called if this candidate is |
| selected by overload resolution. */ |
| tree fn; |
| /* If not NULL_TREE, the first argument to use when calling this |
| function. */ |
| tree first_arg; |
| /* The rest of the arguments to use when calling this function. If |
| there are no further arguments this may be NULL or it may be an |
| empty vector. */ |
| const vec<tree, va_gc> *args; |
| /* The implicit conversion sequences for each of the arguments to |
| FN. */ |
| conversion **convs; |
| /* The number of implicit conversion sequences. */ |
| size_t num_convs; |
| /* If FN is a user-defined conversion, the standard conversion |
| sequence from the type returned by FN to the desired destination |
| type. */ |
| conversion *second_conv; |
| struct rejection_reason *reason; |
| /* If FN is a member function, the binfo indicating the path used to |
| qualify the name of FN at the call site. This path is used to |
| determine whether or not FN is accessible if it is selected by |
| overload resolution. The DECL_CONTEXT of FN will always be a |
| (possibly improper) base of this binfo. */ |
| tree access_path; |
| /* If FN is a non-static member function, the binfo indicating the |
| subobject to which the `this' pointer should be converted if FN |
| is selected by overload resolution. The type pointed to by |
| the `this' pointer must correspond to the most derived class |
| indicated by the CONVERSION_PATH. */ |
| tree conversion_path; |
| tree template_decl; |
| tree explicit_targs; |
| candidate_warning *warnings; |
| z_candidate *next; |
| int viable; |
| |
| /* The flags active in add_candidate. */ |
| int flags; |
| |
| bool rewritten () { return (flags & LOOKUP_REWRITTEN); } |
| bool reversed () { return (flags & LOOKUP_REVERSED); } |
| }; |
| |
| /* Returns true iff T is a null pointer constant in the sense of |
| [conv.ptr]. */ |
| |
| bool |
| null_ptr_cst_p (tree t) |
| { |
| tree type = TREE_TYPE (t); |
| |
| /* [conv.ptr] |
| |
| A null pointer constant is an integer literal ([lex.icon]) with value |
| zero or a prvalue of type std::nullptr_t. */ |
| if (NULLPTR_TYPE_P (type)) |
| return true; |
| |
| if (cxx_dialect >= cxx11) |
| { |
| STRIP_ANY_LOCATION_WRAPPER (t); |
| |
| /* Core issue 903 says only literal 0 is a null pointer constant. */ |
| if (TREE_CODE (t) == INTEGER_CST |
| && !TREE_OVERFLOW (t) |
| && TREE_CODE (type) == INTEGER_TYPE |
| && integer_zerop (t) |
| && !char_type_p (type)) |
| return true; |
| } |
| else if (CP_INTEGRAL_TYPE_P (type)) |
| { |
| t = fold_non_dependent_expr (t, tf_none); |
| STRIP_NOPS (t); |
| if (integer_zerop (t) && !TREE_OVERFLOW (t)) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /* Returns true iff T is a null member pointer value (4.11). */ |
| |
| bool |
| null_member_pointer_value_p (tree t) |
| { |
| tree type = TREE_TYPE (t); |
| if (!type) |
| return false; |
| else if (TYPE_PTRMEMFUNC_P (type)) |
| return (TREE_CODE (t) == CONSTRUCTOR |
| && CONSTRUCTOR_NELTS (t) |
| && integer_zerop (CONSTRUCTOR_ELT (t, 0)->value)); |
| else if (TYPE_PTRDATAMEM_P (type)) |
| return integer_all_onesp (t); |
| else |
| return false; |
| } |
| |
| /* Returns nonzero if PARMLIST consists of only default parms, |
| ellipsis, and/or undeduced parameter packs. */ |
| |
| bool |
| sufficient_parms_p (const_tree parmlist) |
| { |
| for (; parmlist && parmlist != void_list_node; |
| parmlist = TREE_CHAIN (parmlist)) |
| if (!TREE_PURPOSE (parmlist) |
| && !PACK_EXPANSION_P (TREE_VALUE (parmlist))) |
| return false; |
| return true; |
| } |
| |
| /* Allocate N bytes of memory from the conversion obstack. The memory |
| is zeroed before being returned. */ |
| |
| static void * |
| conversion_obstack_alloc (size_t n) |
| { |
| void *p; |
| if (!conversion_obstack_initialized) |
| { |
| gcc_obstack_init (&conversion_obstack); |
| conversion_obstack_initialized = true; |
| } |
| p = obstack_alloc (&conversion_obstack, n); |
| memset (p, 0, n); |
| return p; |
| } |
| |
| /* Allocate rejection reasons. */ |
| |
| static struct rejection_reason * |
| alloc_rejection (enum rejection_reason_code code) |
| { |
| struct rejection_reason *p; |
| p = (struct rejection_reason *) conversion_obstack_alloc (sizeof *p); |
| p->code = code; |
| return p; |
| } |
| |
| static struct rejection_reason * |
| arity_rejection (tree first_arg, int expected, int actual) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_arity); |
| int adjust = first_arg != NULL_TREE; |
| r->u.arity.expected = expected - adjust; |
| r->u.arity.actual = actual - adjust; |
| return r; |
| } |
| |
| static struct rejection_reason * |
| arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to, |
| location_t loc) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_arg_conversion); |
| int adjust = first_arg != NULL_TREE; |
| r->u.conversion.n_arg = n_arg - adjust; |
| r->u.conversion.from = from; |
| r->u.conversion.to_type = to; |
| r->u.conversion.loc = loc; |
| return r; |
| } |
| |
| static struct rejection_reason * |
| bad_arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to, |
| location_t loc) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_bad_arg_conversion); |
| int adjust = first_arg != NULL_TREE; |
| r->u.bad_conversion.n_arg = n_arg - adjust; |
| r->u.bad_conversion.from = from; |
| r->u.bad_conversion.to_type = to; |
| r->u.bad_conversion.loc = loc; |
| return r; |
| } |
| |
| static struct rejection_reason * |
| explicit_conversion_rejection (tree from, tree to) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_explicit_conversion); |
| r->u.conversion.n_arg = 0; |
| r->u.conversion.from = from; |
| r->u.conversion.to_type = to; |
| r->u.conversion.loc = UNKNOWN_LOCATION; |
| return r; |
| } |
| |
| static struct rejection_reason * |
| template_conversion_rejection (tree from, tree to) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_template_conversion); |
| r->u.conversion.n_arg = 0; |
| r->u.conversion.from = from; |
| r->u.conversion.to_type = to; |
| r->u.conversion.loc = UNKNOWN_LOCATION; |
| return r; |
| } |
| |
| static struct rejection_reason * |
| template_unification_rejection (tree tmpl, tree explicit_targs, tree targs, |
| const tree *args, unsigned int nargs, |
| tree return_type, unification_kind_t strict, |
| int flags) |
| { |
| size_t args_n_bytes = sizeof (*args) * nargs; |
| tree *args1 = (tree *) conversion_obstack_alloc (args_n_bytes); |
| struct rejection_reason *r = alloc_rejection (rr_template_unification); |
| r->u.template_unification.tmpl = tmpl; |
| r->u.template_unification.explicit_targs = explicit_targs; |
| r->u.template_unification.num_targs = TREE_VEC_LENGTH (targs); |
| /* Copy args to our own storage. */ |
| memcpy (args1, args, args_n_bytes); |
| r->u.template_unification.args = args1; |
| r->u.template_unification.nargs = nargs; |
| r->u.template_unification.return_type = return_type; |
| r->u.template_unification.strict = strict; |
| r->u.template_unification.flags = flags; |
| return r; |
| } |
| |
| static struct rejection_reason * |
| template_unification_error_rejection (void) |
| { |
| return alloc_rejection (rr_template_unification); |
| } |
| |
| static struct rejection_reason * |
| invalid_copy_with_fn_template_rejection (void) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_invalid_copy); |
| return r; |
| } |
| |
| static struct rejection_reason * |
| inherited_ctor_rejection (void) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_inherited_ctor); |
| return r; |
| } |
| |
| /* Build a constraint failure record. */ |
| |
| static struct rejection_reason * |
| constraint_failure (void) |
| { |
| struct rejection_reason *r = alloc_rejection (rr_constraint_failure); |
| return r; |
| } |
| |
| /* Dynamically allocate a conversion. */ |
| |
| static conversion * |
| alloc_conversion (conversion_kind kind) |
| { |
| conversion *c; |
| c = (conversion *) conversion_obstack_alloc (sizeof (conversion)); |
| c->kind = kind; |
| return c; |
| } |
| |
| /* Make sure that all memory on the conversion obstack has been |
| freed. */ |
| |
| void |
| validate_conversion_obstack (void) |
| { |
| if (conversion_obstack_initialized) |
| gcc_assert ((obstack_next_free (&conversion_obstack) |
| == obstack_base (&conversion_obstack))); |
| } |
| |
| /* Dynamically allocate an array of N conversions. */ |
| |
| static conversion ** |
| alloc_conversions (size_t n) |
| { |
| return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *)); |
| } |
| |
| static conversion * |
| build_conv (conversion_kind code, tree type, conversion *from) |
| { |
| conversion *t; |
| conversion_rank rank = CONVERSION_RANK (from); |
| |
| /* Note that the caller is responsible for filling in t->cand for |
| user-defined conversions. */ |
| t = alloc_conversion (code); |
| t->type = type; |
| t->u.next = from; |
| |
| switch (code) |
| { |
| case ck_ptr: |
| case ck_pmem: |
| case ck_base: |
| case ck_std: |
| if (rank < cr_std) |
| rank = cr_std; |
| break; |
| |
| case ck_qual: |
| case ck_fnptr: |
| if (rank < cr_exact) |
| rank = cr_exact; |
| break; |
| |
| default: |
| break; |
| } |
| t->rank = rank; |
| t->user_conv_p = (code == ck_user || from->user_conv_p); |
| t->bad_p = from->bad_p; |
| t->base_p = false; |
| return t; |
| } |
| |
| /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a |
| specialization of std::initializer_list<T>, if such a conversion is |
| possible. */ |
| |
| static conversion * |
| build_list_conv (tree type, tree ctor, int flags, tsubst_flags_t complain) |
| { |
| tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0); |
| unsigned len = CONSTRUCTOR_NELTS (ctor); |
| conversion **subconvs = alloc_conversions (len); |
| conversion *t; |
| unsigned i; |
| tree val; |
| |
| /* Within a list-initialization we can have more user-defined |
| conversions. */ |
| flags &= ~LOOKUP_NO_CONVERSION; |
| /* But no narrowing conversions. */ |
| flags |= LOOKUP_NO_NARROWING; |
| |
| /* Can't make an array of these types. */ |
| if (TYPE_REF_P (elttype) |
| || TREE_CODE (elttype) == FUNCTION_TYPE |
| || VOID_TYPE_P (elttype)) |
| return NULL; |
| |
| FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val) |
| { |
| conversion *sub |
| = implicit_conversion (elttype, TREE_TYPE (val), val, |
| false, flags, complain); |
| if (sub == NULL) |
| return NULL; |
| |
| subconvs[i] = sub; |
| } |
| |
| t = alloc_conversion (ck_list); |
| t->type = type; |
| t->u.list = subconvs; |
| t->rank = cr_exact; |
| |
| for (i = 0; i < len; ++i) |
| { |
| conversion *sub = subconvs[i]; |
| if (sub->rank > t->rank) |
| t->rank = sub->rank; |
| if (sub->user_conv_p) |
| t->user_conv_p = true; |
| if (sub->bad_p) |
| t->bad_p = true; |
| } |
| |
| return t; |
| } |
| |
| /* Return the next conversion of the conversion chain (if applicable), |
| or NULL otherwise. Please use this function instead of directly |
| accessing fields of struct conversion. */ |
| |
| static conversion * |
| next_conversion (conversion *conv) |
| { |
| if (conv == NULL |
| || conv->kind == ck_identity |
| || conv->kind == ck_ambig |
| || conv->kind == ck_list |
| || conv->kind == ck_aggr) |
| return NULL; |
| return conv->u.next; |
| } |
| |
| /* Strip to the first ck_user, ck_ambig, ck_list, ck_aggr or ck_identity |
| encountered. */ |
| |
| static conversion * |
| strip_standard_conversion (conversion *conv) |
| { |
| while (conv |
| && conv->kind != ck_user |
| && conv->kind != ck_ambig |
| && conv->kind != ck_list |
| && conv->kind != ck_aggr |
| && conv->kind != ck_identity) |
| conv = next_conversion (conv); |
| return conv; |
| } |
| |
| /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list, |
| is a valid aggregate initializer for array type ATYPE. */ |
| |
| static bool |
| can_convert_array (tree atype, tree ctor, int flags, tsubst_flags_t complain) |
| { |
| unsigned i; |
| tree elttype = TREE_TYPE (atype); |
| for (i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i) |
| { |
| tree val = CONSTRUCTOR_ELT (ctor, i)->value; |
| bool ok; |
| if (TREE_CODE (elttype) == ARRAY_TYPE |
| && TREE_CODE (val) == CONSTRUCTOR) |
| ok = can_convert_array (elttype, val, flags, complain); |
| else |
| ok = can_convert_arg (elttype, TREE_TYPE (val), val, flags, |
| complain); |
| if (!ok) |
| return false; |
| } |
| return true; |
| } |
| |
| /* Helper for build_aggr_conv. Return true if FIELD is in PSET, or if |
| FIELD has ANON_AGGR_TYPE_P and any initializable field in there recursively |
| is in PSET. */ |
| |
| static bool |
| field_in_pset (hash_set<tree, true> &pset, tree field) |
| { |
| if (pset.contains (field)) |
| return true; |
| if (ANON_AGGR_TYPE_P (TREE_TYPE (field))) |
| for (field = TYPE_FIELDS (TREE_TYPE (field)); |
| field; field = DECL_CHAIN (field)) |
| { |
| field = next_initializable_field (field); |
| if (field == NULL_TREE) |
| break; |
| if (field_in_pset (pset, field)) |
| return true; |
| } |
| return false; |
| } |
| |
| /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an |
| aggregate class, if such a conversion is possible. */ |
| |
| static conversion * |
| build_aggr_conv (tree type, tree ctor, int flags, tsubst_flags_t complain) |
| { |
| unsigned HOST_WIDE_INT i = 0; |
| conversion *c; |
| tree field = next_initializable_field (TYPE_FIELDS (type)); |
| tree empty_ctor = NULL_TREE; |
| hash_set<tree, true> pset; |
| |
| /* We already called reshape_init in implicit_conversion. */ |
| |
| /* The conversions within the init-list aren't affected by the enclosing |
| context; they're always simple copy-initialization. */ |
| flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING; |
| |
| /* For designated initializers, verify that each initializer is convertible |
| to corresponding TREE_TYPE (ce->index) and mark those FIELD_DECLs as |
| visited. In the following loop then ignore already visited |
| FIELD_DECLs. */ |
| if (CONSTRUCTOR_IS_DESIGNATED_INIT (ctor)) |
| { |
| tree idx, val; |
| FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), i, idx, val) |
| { |
| if (idx && TREE_CODE (idx) == FIELD_DECL) |
| { |
| tree ftype = TREE_TYPE (idx); |
| bool ok; |
| |
| if (TREE_CODE (ftype) == ARRAY_TYPE |
| && TREE_CODE (val) == CONSTRUCTOR) |
| ok = can_convert_array (ftype, val, flags, complain); |
| else |
| ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags, |
| complain); |
| |
| if (!ok) |
| return NULL; |
| /* For unions, there should be just one initializer. */ |
| if (TREE_CODE (type) == UNION_TYPE) |
| { |
| field = NULL_TREE; |
| i = 1; |
| break; |
| } |
| pset.add (idx); |
| } |
| else |
| return NULL; |
| } |
| } |
| |
| for (; field; field = next_initializable_field (DECL_CHAIN (field))) |
| { |
| tree ftype = TREE_TYPE (field); |
| tree val; |
| bool ok; |
| |
| if (!pset.is_empty () && field_in_pset (pset, field)) |
| continue; |
| if (i < CONSTRUCTOR_NELTS (ctor)) |
| { |
| val = CONSTRUCTOR_ELT (ctor, i)->value; |
| ++i; |
| } |
| else if (DECL_INITIAL (field)) |
| val = get_nsdmi (field, /*ctor*/false, complain); |
| else if (TYPE_REF_P (ftype)) |
| /* Value-initialization of reference is ill-formed. */ |
| return NULL; |
| else |
| { |
| if (empty_ctor == NULL_TREE) |
| empty_ctor = build_constructor (init_list_type_node, NULL); |
| val = empty_ctor; |
| } |
| |
| if (TREE_CODE (ftype) == ARRAY_TYPE |
| && TREE_CODE (val) == CONSTRUCTOR) |
| ok = can_convert_array (ftype, val, flags, complain); |
| else |
| ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags, |
| complain); |
| |
| if (!ok) |
| return NULL; |
| |
| if (TREE_CODE (type) == UNION_TYPE) |
| break; |
| } |
| |
| if (i < CONSTRUCTOR_NELTS (ctor)) |
| return NULL; |
| |
| c = alloc_conversion (ck_aggr); |
| c->type = type; |
| c->rank = cr_exact; |
| c->user_conv_p = true; |
| c->check_narrowing = true; |
| c->u.expr = ctor; |
| return c; |
| } |
| |
| /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an |
| array type, if such a conversion is possible. */ |
| |
| static conversion * |
| build_array_conv (tree type, tree ctor, int flags, tsubst_flags_t complain) |
| { |
| conversion *c; |
| unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor); |
| tree elttype = TREE_TYPE (type); |
| unsigned i; |
| tree val; |
| bool bad = false; |
| bool user = false; |
| enum conversion_rank rank = cr_exact; |
| |
| /* We might need to propagate the size from the element to the array. */ |
| complete_type (type); |
| |
| if (TYPE_DOMAIN (type) |
| && !variably_modified_type_p (TYPE_DOMAIN (type), NULL_TREE)) |
| { |
| unsigned HOST_WIDE_INT alen = tree_to_uhwi (array_type_nelts_top (type)); |
| if (alen < len) |
| return NULL; |
| } |
| |
| flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING; |
| |
| FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val) |
| { |
| conversion *sub |
| = implicit_conversion (elttype, TREE_TYPE (val), val, |
| false, flags, complain); |
| if (sub == NULL) |
| return NULL; |
| |
| if (sub->rank > rank) |
| rank = sub->rank; |
| if (sub->user_conv_p) |
| user = true; |
| if (sub->bad_p) |
| bad = true; |
| } |
| |
| c = alloc_conversion (ck_aggr); |
| c->type = type; |
| c->rank = rank; |
| c->user_conv_p = user; |
| c->bad_p = bad; |
| c->u.expr = ctor; |
| return c; |
| } |
| |
| /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a |
| complex type, if such a conversion is possible. */ |
| |
| static conversion * |
| build_complex_conv (tree type, tree ctor, int flags, |
| tsubst_flags_t complain) |
| { |
| conversion *c; |
| unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor); |
| tree elttype = TREE_TYPE (type); |
| unsigned i; |
| tree val; |
| bool bad = false; |
| bool user = false; |
| enum conversion_rank rank = cr_exact; |
| |
| if (len != 2) |
| return NULL; |
| |
| flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING; |
| |
| FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val) |
| { |
| conversion *sub |
| = implicit_conversion (elttype, TREE_TYPE (val), val, |
| false, flags, complain); |
| if (sub == NULL) |
| return NULL; |
| |
| if (sub->rank > rank) |
| rank = sub->rank; |
| if (sub->user_conv_p) |
| user = true; |
| if (sub->bad_p) |
| bad = true; |
| } |
| |
| c = alloc_conversion (ck_aggr); |
| c->type = type; |
| c->rank = rank; |
| c->user_conv_p = user; |
| c->bad_p = bad; |
| c->u.expr = ctor; |
| return c; |
| } |
| |
| /* Build a representation of the identity conversion from EXPR to |
| itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */ |
| |
| static conversion * |
| build_identity_conv (tree type, tree expr) |
| { |
| conversion *c; |
| |
| c = alloc_conversion (ck_identity); |
| c->type = type; |
| c->u.expr = expr; |
| |
| return c; |
| } |
| |
| /* Converting from EXPR to TYPE was ambiguous in the sense that there |
| were multiple user-defined conversions to accomplish the job. |
| Build a conversion that indicates that ambiguity. */ |
| |
| static conversion * |
| build_ambiguous_conv (tree type, tree expr) |
| { |
| conversion *c; |
| |
| c = alloc_conversion (ck_ambig); |
| c->type = type; |
| c->u.expr = expr; |
| |
| return c; |
| } |
| |
| tree |
| strip_top_quals (tree t) |
| { |
| if (TREE_CODE (t) == ARRAY_TYPE) |
| return t; |
| return cp_build_qualified_type (t, 0); |
| } |
| |
| /* Returns the standard conversion path (see [conv]) from type FROM to type |
| TO, if any. For proper handling of null pointer constants, you must |
| also pass the expression EXPR to convert from. If C_CAST_P is true, |
| this conversion is coming from a C-style cast. */ |
| |
| static conversion * |
| standard_conversion (tree to, tree from, tree expr, bool c_cast_p, |
| int flags, tsubst_flags_t complain) |
| { |
| enum tree_code fcode, tcode; |
| conversion *conv; |
| bool fromref = false; |
| tree qualified_to; |
| |
| to = non_reference (to); |
| if (TYPE_REF_P (from)) |
| { |
| fromref = true; |
| from = TREE_TYPE (from); |
| } |
| qualified_to = to; |
| to = strip_top_quals (to); |
| from = strip_top_quals (from); |
| |
| if (expr && type_unknown_p (expr)) |
| { |
| if (TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to)) |
| { |
| tsubst_flags_t tflags = tf_conv; |
| expr = instantiate_type (to, expr, tflags); |
| if (expr == error_mark_node) |
| return NULL; |
| from = TREE_TYPE (expr); |
| } |
| else if (TREE_CODE (to) == BOOLEAN_TYPE) |
| { |
| /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */ |
| expr = resolve_nondeduced_context (expr, complain); |
| from = TREE_TYPE (expr); |
| } |
| } |
| |
| fcode = TREE_CODE (from); |
| tcode = TREE_CODE (to); |
| |
| conv = build_identity_conv (from, expr); |
| if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE) |
| { |
| from = type_decays_to (from); |
| fcode = TREE_CODE (from); |
| /* Tell convert_like_real that we're using the address. */ |
| conv->rvaluedness_matches_p = true; |
| conv = build_conv (ck_lvalue, from, conv); |
| } |
| /* Wrapping a ck_rvalue around a class prvalue (as a result of using |
| obvalue_p) seems odd, since it's already a prvalue, but that's how we |
| express the copy constructor call required by copy-initialization. */ |
| else if (fromref || (expr && obvalue_p (expr))) |
| { |
| if (expr) |
| { |
| tree bitfield_type; |
| bitfield_type = is_bitfield_expr_with_lowered_type (expr); |
| if (bitfield_type) |
| { |
| from = strip_top_quals (bitfield_type); |
| fcode = TREE_CODE (from); |
| } |
| } |
| conv = build_conv (ck_rvalue, from, conv); |
| if (flags & LOOKUP_PREFER_RVALUE) |
| /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */ |
| conv->rvaluedness_matches_p = true; |
| /* If we're performing copy-initialization, remember to skip |
| explicit constructors. */ |
| if (flags & LOOKUP_ONLYCONVERTING) |
| conv->copy_init_p = true; |
| } |
| |
| /* Allow conversion between `__complex__' data types. */ |
| if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE) |
| { |
| /* The standard conversion sequence to convert FROM to TO is |
| the standard conversion sequence to perform componentwise |
| conversion. */ |
| conversion *part_conv = standard_conversion |
| (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags, |
| complain); |
| |
| if (part_conv) |
| { |
| conv = build_conv (part_conv->kind, to, conv); |
| conv->rank = part_conv->rank; |
| } |
| else |
| conv = NULL; |
| |
| return conv; |
| } |
| |
| if (same_type_p (from, to)) |
| { |
| if (CLASS_TYPE_P (to) && conv->kind == ck_rvalue) |
| conv->type = qualified_to; |
| return conv; |
| } |
| |
| /* [conv.ptr] |
| A null pointer constant can be converted to a pointer type; ... A |
| null pointer constant of integral type can be converted to an |
| rvalue of type std::nullptr_t. */ |
| if ((tcode == POINTER_TYPE || TYPE_PTRMEM_P (to) |
| || NULLPTR_TYPE_P (to)) |
| && ((expr && null_ptr_cst_p (expr)) |
| || NULLPTR_TYPE_P (from))) |
| conv = build_conv (ck_std, to, conv); |
| else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE) |
| || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE)) |
| { |
| /* For backwards brain damage compatibility, allow interconversion of |
| pointers and integers with a pedwarn. */ |
| conv = build_conv (ck_std, to, conv); |
| conv->bad_p = true; |
| } |
| else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE) |
| { |
| /* For backwards brain damage compatibility, allow interconversion of |
| enums and integers with a pedwarn. */ |
| conv = build_conv (ck_std, to, conv); |
| conv->bad_p = true; |
| } |
| else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE) |
| || (TYPE_PTRDATAMEM_P (to) && TYPE_PTRDATAMEM_P (from))) |
| { |
| tree to_pointee; |
| tree from_pointee; |
| |
| if (tcode == POINTER_TYPE) |
| { |
| to_pointee = TREE_TYPE (to); |
| from_pointee = TREE_TYPE (from); |
| |
| /* Since this is the target of a pointer, it can't have function |
| qualifiers, so any TYPE_QUALS must be for attributes const or |
| noreturn. Strip them. */ |
| if (TREE_CODE (to_pointee) == FUNCTION_TYPE |
| && TYPE_QUALS (to_pointee)) |
| to_pointee = build_qualified_type (to_pointee, TYPE_UNQUALIFIED); |
| if (TREE_CODE (from_pointee) == FUNCTION_TYPE |
| && TYPE_QUALS (from_pointee)) |
| from_pointee = build_qualified_type (from_pointee, TYPE_UNQUALIFIED); |
| } |
| else |
| { |
| to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to); |
| from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from); |
| } |
| |
| if (tcode == POINTER_TYPE |
| && same_type_ignoring_top_level_qualifiers_p (from_pointee, |
| to_pointee)) |
| ; |
| else if (VOID_TYPE_P (to_pointee) |
| && !TYPE_PTRDATAMEM_P (from) |
| && TREE_CODE (from_pointee) != FUNCTION_TYPE) |
| { |
| tree nfrom = TREE_TYPE (from); |
| /* Don't try to apply restrict to void. */ |
| int quals = cp_type_quals (nfrom) & ~TYPE_QUAL_RESTRICT; |
| from_pointee = cp_build_qualified_type (void_type_node, quals); |
| from = build_pointer_type (from_pointee); |
| conv = build_conv (ck_ptr, from, conv); |
| } |
| else if (TYPE_PTRDATAMEM_P (from)) |
| { |
| tree fbase = TYPE_PTRMEM_CLASS_TYPE (from); |
| tree tbase = TYPE_PTRMEM_CLASS_TYPE (to); |
| |
| if (same_type_p (fbase, tbase)) |
| /* No base conversion needed. */; |
| else if (DERIVED_FROM_P (fbase, tbase) |
| && (same_type_ignoring_top_level_qualifiers_p |
| (from_pointee, to_pointee))) |
| { |
| from = build_ptrmem_type (tbase, from_pointee); |
| conv = build_conv (ck_pmem, from, conv); |
| } |
| else |
| return NULL; |
| } |
| else if (CLASS_TYPE_P (from_pointee) |
| && CLASS_TYPE_P (to_pointee) |
| /* [conv.ptr] |
| |
| An rvalue of type "pointer to cv D," where D is a |
| class type, can be converted to an rvalue of type |
| "pointer to cv B," where B is a base class (clause |
| _class.derived_) of D. If B is an inaccessible |
| (clause _class.access_) or ambiguous |
| (_class.member.lookup_) base class of D, a program |
| that necessitates this conversion is ill-formed. |
| Therefore, we use DERIVED_FROM_P, and do not check |
| access or uniqueness. */ |
| && DERIVED_FROM_P (to_pointee, from_pointee)) |
| { |
| from_pointee |
| = cp_build_qualified_type (to_pointee, |
| cp_type_quals (from_pointee)); |
| from = build_pointer_type (from_pointee); |
| conv = build_conv (ck_ptr, from, conv); |
| conv->base_p = true; |
| } |
| |
| if (same_type_p (from, to)) |
| /* OK */; |
| else if (c_cast_p && comp_ptr_ttypes_const (to, from, bounds_either)) |
| /* In a C-style cast, we ignore CV-qualification because we |
| are allowed to perform a static_cast followed by a |
| const_cast. */ |
| conv = build_conv (ck_qual, to, conv); |
| else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee)) |
| conv = build_conv (ck_qual, to, conv); |
| else if (expr && string_conv_p (to, expr, 0)) |
| /* converting from string constant to char *. */ |
| conv = build_conv (ck_qual, to, conv); |
| else if (fnptr_conv_p (to, from)) |
| conv = build_conv (ck_fnptr, to, conv); |
| /* Allow conversions among compatible ObjC pointer types (base |
| conversions have been already handled above). */ |
| else if (c_dialect_objc () |
| && objc_compare_types (to, from, -4, NULL_TREE)) |
| conv = build_conv (ck_ptr, to, conv); |
| else if (ptr_reasonably_similar (to_pointee, from_pointee)) |
| { |
| conv = build_conv (ck_ptr, to, conv); |
| conv->bad_p = true; |
| } |
| else |
| return NULL; |
| |
| from = to; |
| } |
| else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from)) |
| { |
| tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from)); |
| tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to)); |
| tree fbase = class_of_this_parm (fromfn); |
| tree tbase = class_of_this_parm (tofn); |
| |
| /* If FBASE and TBASE are equivalent but incomplete, DERIVED_FROM_P |
| yields false. But a pointer to member of incomplete class is OK. */ |
| if (!same_type_p (fbase, tbase) && !DERIVED_FROM_P (fbase, tbase)) |
| return NULL; |
| |
| tree fstat = static_fn_type (fromfn); |
| tree tstat = static_fn_type (tofn); |
| if (same_type_p (tstat, fstat) |
| || fnptr_conv_p (tstat, fstat)) |
| /* OK */; |
| else |
| return NULL; |
| |
| if (!same_type_p (fbase, tbase)) |
| { |
| from = build_memfn_type (fstat, |
| tbase, |
| cp_type_quals (tbase), |
| type_memfn_rqual (tofn)); |
| from = build_ptrmemfunc_type (build_pointer_type (from)); |
| conv = build_conv (ck_pmem, from, conv); |
| conv->base_p = true; |
| } |
| if (fnptr_conv_p (tstat, fstat)) |
| conv = build_conv (ck_fnptr, to, conv); |
| } |
| else if (tcode == BOOLEAN_TYPE) |
| { |
| /* [conv.bool] |
| |
| A prvalue of arithmetic, unscoped enumeration, pointer, or pointer |
| to member type can be converted to a prvalue of type bool. ... |
| For direct-initialization (8.5 [dcl.init]), a prvalue of type |
| std::nullptr_t can be converted to a prvalue of type bool; */ |
| if (ARITHMETIC_TYPE_P (from) |
| || UNSCOPED_ENUM_P (from) |
| || fcode == POINTER_TYPE |
| || TYPE_PTRMEM_P (from) |
| || NULLPTR_TYPE_P (from)) |
| { |
| conv = build_conv (ck_std, to, conv); |
| if (fcode == POINTER_TYPE |
| || TYPE_PTRDATAMEM_P (from) |
| || (TYPE_PTRMEMFUNC_P (from) |
| && conv->rank < cr_pbool) |
| || NULLPTR_TYPE_P (from)) |
| conv->rank = cr_pbool; |
| if (NULLPTR_TYPE_P (from) && (flags & LOOKUP_ONLYCONVERTING)) |
| conv->bad_p = true; |
| if (flags & LOOKUP_NO_NARROWING) |
| conv->check_narrowing = true; |
| return conv; |
| } |
| |
| return NULL; |
| } |
| /* We don't check for ENUMERAL_TYPE here because there are no standard |
| conversions to enum type. */ |
| /* As an extension, allow conversion to complex type. */ |
| else if (ARITHMETIC_TYPE_P (to)) |
| { |
| if (! (INTEGRAL_CODE_P (fcode) |
| || (fcode == REAL_TYPE && !(flags & LOOKUP_NO_NON_INTEGRAL))) |
| || SCOPED_ENUM_P (from)) |
| return NULL; |
| |
| /* If we're parsing an enum with no fixed underlying type, we're |
| dealing with an incomplete type, which renders the conversion |
| ill-formed. */ |
| if (!COMPLETE_TYPE_P (from)) |
| return NULL; |
| |
| conv = build_conv (ck_std, to, conv); |
| |
| tree underlying_type = NULL_TREE; |
| if (TREE_CODE (from) == ENUMERAL_TYPE |
| && ENUM_FIXED_UNDERLYING_TYPE_P (from)) |
| underlying_type = ENUM_UNDERLYING_TYPE (from); |
| |
| /* Give this a better rank if it's a promotion. |
| |
| To handle CWG 1601, also bump the rank if we are converting |
| an enumeration with a fixed underlying type to the underlying |
| type. */ |
| if ((same_type_p (to, type_promotes_to (from)) |
| || (underlying_type && same_type_p (to, underlying_type))) |
| && next_conversion (conv)->rank <= cr_promotion) |
| conv->rank = cr_promotion; |
| } |
| else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE |
| && vector_types_convertible_p (from, to, false)) |
| return build_conv (ck_std, to, conv); |
| else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from) |
| && is_properly_derived_from (from, to)) |
| { |
| if (conv->kind == ck_rvalue) |
| conv = next_conversion (conv); |
| conv = build_conv (ck_base, to, conv); |
| /* The derived-to-base conversion indicates the initialization |
| of a parameter with base type from an object of a derived |
| type. A temporary object is created to hold the result of |
| the conversion unless we're binding directly to a reference. */ |
| conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND); |
| if (flags & LOOKUP_PREFER_RVALUE) |
| /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */ |
| conv->rvaluedness_matches_p = true; |
| /* If we're performing copy-initialization, remember to skip |
| explicit constructors. */ |
| if (flags & LOOKUP_ONLYCONVERTING) |
| conv->copy_init_p = true; |
| } |
| else |
| return NULL; |
| |
| if (flags & LOOKUP_NO_NARROWING) |
| conv->check_narrowing = true; |
| |
| return conv; |
| } |
| |
| /* Returns nonzero if T1 is reference-related to T2. */ |
| |
| bool |
| reference_related_p (tree t1, tree t2) |
| { |
| if (t1 == error_mark_node || t2 == error_mark_node) |
| return false; |
| |
| t1 = TYPE_MAIN_VARIANT (t1); |
| t2 = TYPE_MAIN_VARIANT (t2); |
| |
| /* [dcl.init.ref] |
| |
| Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related |
| to "cv2 T2" if T1 is similar to T2, or T1 is a base class of T2. */ |
| return (similar_type_p (t1, t2) |
| || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2) |
| && DERIVED_FROM_P (t1, t2))); |
| } |
| |
| /* Returns nonzero if T1 is reference-compatible with T2. */ |
| |
| bool |
| reference_compatible_p (tree t1, tree t2) |
| { |
| /* [dcl.init.ref] |
| |
| "cv1 T1" is reference compatible with "cv2 T2" if |
| a prvalue of type "pointer to cv2 T2" can be converted to the type |
| "pointer to cv1 T1" via a standard conversion sequence. */ |
| tree ptype1 = build_pointer_type (t1); |
| tree ptype2 = build_pointer_type (t2); |
| conversion *conv = standard_conversion (ptype1, ptype2, NULL_TREE, |
| /*c_cast_p=*/false, 0, tf_none); |
| if (!conv || conv->bad_p) |
| return false; |
| return true; |
| } |
| |
| /* Return true if converting FROM to TO would involve a qualification |
| conversion. */ |
| |
| static bool |
| involves_qualification_conversion_p (tree to, tree from) |
| { |
| /* If we're not convering a pointer to another one, we won't get |
| a qualification conversion. */ |
| if (!((TYPE_PTR_P (to) && TYPE_PTR_P (from)) |
| || (TYPE_PTRDATAMEM_P (to) && TYPE_PTRDATAMEM_P (from)))) |
| return false; |
| |
| conversion *conv = standard_conversion (to, from, NULL_TREE, |
| /*c_cast_p=*/false, 0, tf_none); |
| for (conversion *t = conv; t; t = next_conversion (t)) |
| if (t->kind == ck_qual) |
| return true; |
| |
| return false; |
| } |
| |
| /* A reference of the indicated TYPE is being bound directly to the |
| expression represented by the implicit conversion sequence CONV. |
| Return a conversion sequence for this binding. */ |
| |
| static conversion * |
| direct_reference_binding (tree type, conversion *conv) |
| { |
| tree t; |
| |
| gcc_assert (TYPE_REF_P (type)); |
| gcc_assert (!TYPE_REF_P (conv->type)); |
| |
| t = TREE_TYPE (type); |
| |
| if (conv->kind == ck_identity) |
| /* Mark the identity conv as to not decay to rvalue. */ |
| conv->rvaluedness_matches_p = true; |
| |
| /* [over.ics.rank] |
| |
| When a parameter of reference type binds directly |
| (_dcl.init.ref_) to an argument expression, the implicit |
| conversion sequence is the identity conversion, unless the |
| argument expression has a type that is a derived class of the |
| parameter type, in which case the implicit conversion sequence is |
| a derived-to-base Conversion. |
| |
| If the parameter binds directly to the result of applying a |
| conversion function to the argument expression, the implicit |
| conversion sequence is a user-defined conversion sequence |
| (_over.ics.user_), with the second standard conversion sequence |
| either an identity conversion or, if the conversion function |
| returns an entity of a type that is a derived class of the |
| parameter type, a derived-to-base conversion. */ |
| if (is_properly_derived_from (conv->type, t)) |
| { |
| /* Represent the derived-to-base conversion. */ |
| conv = build_conv (ck_base, t, conv); |
| /* We will actually be binding to the base-class subobject in |
| the derived class, so we mark this conversion appropriately. |
| That way, convert_like knows not to generate a temporary. */ |
| conv->need_temporary_p = false; |
| } |
| else if (involves_qualification_conversion_p (t, conv->type)) |
| /* Represent the qualification conversion. After DR 2352 |
| #1 and #2 were indistinguishable conversion sequences: |
| |
| void f(int*); // #1 |
| void f(const int* const &); // #2 |
| void g(int* p) { f(p); } |
| |
| because the types "int *" and "const int *const" are |
| reference-related and we were binding both directly and they |
| had the same rank. To break it up, we add a ck_qual under the |
| ck_ref_bind so that conversion sequence ranking chooses #1. */ |
| conv = build_conv (ck_qual, t, conv); |
| |
| return build_conv (ck_ref_bind, type, conv); |
| } |
| |
| /* Returns the conversion path from type FROM to reference type TO for |
| purposes of reference binding. For lvalue binding, either pass a |
| reference type to FROM or an lvalue expression to EXPR. If the |
| reference will be bound to a temporary, NEED_TEMPORARY_P is set for |
| the conversion returned. If C_CAST_P is true, this |
| conversion is coming from a C-style cast. */ |
| |
| static conversion * |
| reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags, |
| tsubst_flags_t complain) |
| { |
| conversion *conv = NULL; |
| tree to = TREE_TYPE (rto); |
| tree from = rfrom; |
| tree tfrom; |
| bool related_p; |
| bool compatible_p; |
| cp_lvalue_kind gl_kind; |
| bool is_lvalue; |
| |
| if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr)) |
| { |
| expr = instantiate_type (to, expr, tf_none); |
| if (expr == error_mark_node) |
| return NULL; |
| from = TREE_TYPE (expr); |
| } |
| |
| bool copy_list_init = false; |
| if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr)) |
| { |
| maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS); |
| /* DR 1288: Otherwise, if the initializer list has a single element |
| of type E and ... [T's] referenced type is reference-related to E, |
| the object or reference is initialized from that element... |
| |
| ??? With P0388R4, we should bind 't' directly to U{}: |
| using U = A[2]; |
| A (&&t)[] = {U{}}; |
| because A[] and A[2] are reference-related. But we don't do it |
| because grok_reference_init has deduced the array size (to 1), and |
| A[1] and A[2] aren't reference-related. */ |
| if (CONSTRUCTOR_NELTS (expr) == 1) |
| { |
| tree elt = CONSTRUCTOR_ELT (expr, 0)->value; |
| if (error_operand_p (elt)) |
| return NULL; |
| tree etype = TREE_TYPE (elt); |
| if (reference_related_p (to, etype)) |
| { |
| expr = elt; |
| from = etype; |
| goto skip; |
| } |
| } |
| /* Otherwise, if T is a reference type, a prvalue temporary of the type |
| referenced by T is copy-list-initialized, and the reference is bound |
| to that temporary. */ |
| copy_list_init = true; |
| skip:; |
| } |
| |
| if (TYPE_REF_P (from)) |
| { |
| from = TREE_TYPE (from); |
| if (!TYPE_REF_IS_RVALUE (rfrom) |
| || TREE_CODE (from) == FUNCTION_TYPE) |
| gl_kind = clk_ordinary; |
| else |
| gl_kind = clk_rvalueref; |
| } |
| else if (expr) |
| gl_kind = lvalue_kind (expr); |
| else if (CLASS_TYPE_P (from) |
| || TREE_CODE (from) == ARRAY_TYPE) |
| gl_kind = clk_class; |
| else |
| gl_kind = clk_none; |
| |
| /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */ |
| if ((flags & LOOKUP_NO_TEMP_BIND) |
| && (gl_kind & clk_class)) |
| gl_kind = clk_none; |
| |
| /* Same mask as real_lvalue_p. */ |
| is_lvalue = gl_kind && !(gl_kind & (clk_rvalueref|clk_class)); |
| |
| tfrom = from; |
| if ((gl_kind & clk_bitfield) != 0) |
| tfrom = unlowered_expr_type (expr); |
| |
| /* Figure out whether or not the types are reference-related and |
| reference compatible. We have to do this after stripping |
| references from FROM. */ |
| related_p = reference_related_p (to, tfrom); |
| /* If this is a C cast, first convert to an appropriately qualified |
| type, so that we can later do a const_cast to the desired type. */ |
| if (related_p && c_cast_p |
| && !at_least_as_qualified_p (to, tfrom)) |
| to = cp_build_qualified_type (to, cp_type_quals (tfrom)); |
| compatible_p = reference_compatible_p (to, tfrom); |
| |
| /* Directly bind reference when target expression's type is compatible with |
| the reference and expression is an lvalue. In DR391, the wording in |
| [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for |
| const and rvalue references to rvalues of compatible class type. |
| We should also do direct bindings for non-class xvalues. */ |
| if ((related_p || compatible_p) && gl_kind) |
| { |
| /* [dcl.init.ref] |
| |
| If the initializer expression |
| |
| -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1" |
| is reference-compatible with "cv2 T2," |
| |
| the reference is bound directly to the initializer expression |
| lvalue. |
| |
| [...] |
| If the initializer expression is an rvalue, with T2 a class type, |
| and "cv1 T1" is reference-compatible with "cv2 T2", the reference |
| is bound to the object represented by the rvalue or to a sub-object |
| within that object. */ |
| |
| conv = build_identity_conv (tfrom, expr); |
| conv = direct_reference_binding (rto, conv); |
| |
| if (TYPE_REF_P (rfrom)) |
| /* Handle rvalue reference to function properly. */ |
| conv->rvaluedness_matches_p |
| = (TYPE_REF_IS_RVALUE (rto) == TYPE_REF_IS_RVALUE (rfrom)); |
| else |
| conv->rvaluedness_matches_p |
| = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue); |
| |
| if ((gl_kind & clk_bitfield) != 0 |
| || ((gl_kind & clk_packed) != 0 && !TYPE_PACKED (to))) |
| /* For the purposes of overload resolution, we ignore the fact |
| this expression is a bitfield or packed field. (In particular, |
| [over.ics.ref] says specifically that a function with a |
| non-const reference parameter is viable even if the |
| argument is a bitfield.) |
| |
| However, when we actually call the function we must create |
| a temporary to which to bind the reference. If the |
| reference is volatile, or isn't const, then we cannot make |
| a temporary, so we just issue an error when the conversion |
| actually occurs. */ |
| conv->need_temporary_p = true; |
| |
| /* Don't allow binding of lvalues (other than function lvalues) to |
| rvalue references. */ |
| if (is_lvalue && TYPE_REF_IS_RVALUE (rto) |
| && TREE_CODE (to) != FUNCTION_TYPE) |
| conv->bad_p = true; |
| |
| /* Nor the reverse. */ |
| if (!is_lvalue && !TYPE_REF_IS_RVALUE (rto) |
| && (!CP_TYPE_CONST_NON_VOLATILE_P (to) |
| || (flags & LOOKUP_NO_RVAL_BIND)) |
| && TREE_CODE (to) != FUNCTION_TYPE) |
| conv->bad_p = true; |
| |
| if (!compatible_p) |
| conv->bad_p = true; |
| |
| return conv; |
| } |
| /* [class.conv.fct] A conversion function is never used to convert a |
| (possibly cv-qualified) object to the (possibly cv-qualified) same |
| object type (or a reference to it), to a (possibly cv-qualified) base |
| class of that type (or a reference to it).... */ |
| else if (CLASS_TYPE_P (from) && !related_p |
| && !(flags & LOOKUP_NO_CONVERSION)) |
| { |
| /* [dcl.init.ref] |
| |
| If the initializer expression |
| |
| -- has a class type (i.e., T2 is a class type) can be |
| implicitly converted to an lvalue of type "cv3 T3," where |
| "cv1 T1" is reference-compatible with "cv3 T3". (this |
| conversion is selected by enumerating the applicable |
| conversion functions (_over.match.ref_) and choosing the |
| best one through overload resolution. (_over.match_). |
| |
| the reference is bound to the lvalue result of the conversion |
| in the second case. */ |
| z_candidate *cand = build_user_type_conversion_1 (rto, expr, flags, |
| complain); |
| if (cand) |
| return cand->second_conv; |
| } |
| |
| /* From this point on, we conceptually need temporaries, even if we |
| elide them. Only the cases above are "direct bindings". */ |
| if (flags & LOOKUP_NO_TEMP_BIND) |
| return NULL; |
| |
| /* [over.ics.rank] |
| |
| When a parameter of reference type is not bound directly to an |
| argument expression, the conversion sequence is the one required |
| to convert the argument expression to the underlying type of the |
| reference according to _over.best.ics_. Conceptually, this |
| conversion sequence corresponds to copy-initializing a temporary |
| of the underlying type with the argument expression. Any |
| difference in top-level cv-qualification is subsumed by the |
| initialization itself and does not constitute a conversion. */ |
| |
| /* [dcl.init.ref] |
| |
| Otherwise, the reference shall be an lvalue reference to a |
| non-volatile const type, or the reference shall be an rvalue |
| reference. |
| |
| We try below to treat this as a bad conversion to improve diagnostics, |
| but if TO is an incomplete class, we need to reject this conversion |
| now to avoid unnecessary instantiation. */ |
| if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto) |
| && !COMPLETE_TYPE_P (to)) |
| return NULL; |
| |
| /* We're generating a temporary now, but don't bind any more in the |
| conversion (specifically, don't slice the temporary returned by a |
| conversion operator). */ |
| flags |= LOOKUP_NO_TEMP_BIND; |
| |
| /* Core issue 899: When [copy-]initializing a temporary to be bound |
| to the first parameter of a copy constructor (12.8) called with |
| a single argument in the context of direct-initialization, |
| explicit conversion functions are also considered. |
| |
| So don't set LOOKUP_ONLYCONVERTING in that case. */ |
| if (!(flags & LOOKUP_COPY_PARM)) |
| flags |= LOOKUP_ONLYCONVERTING; |
| |
| if (!conv) |
| conv = implicit_conversion (to, from, expr, c_cast_p, |
| flags, complain); |
| if (!conv) |
| return NULL; |
| |
| if (conv->user_conv_p) |
| { |
| if (copy_list_init) |
| /* Remember this was copy-list-initialization. */ |
| conv->need_temporary_p = true; |
| |
| /* If initializing the temporary used a conversion function, |
| recalculate the second conversion sequence. */ |
| for (conversion *t = conv; t; t = next_conversion (t)) |
| if (t->kind == ck_user |
| && DECL_CONV_FN_P (t->cand->fn)) |
| { |
| tree ftype = TREE_TYPE (TREE_TYPE (t->cand->fn)); |
| /* A prvalue of non-class type is cv-unqualified. */ |
| if (!TYPE_REF_P (ftype) && !CLASS_TYPE_P (ftype)) |
| ftype = cv_unqualified (ftype); |
| int sflags = (flags|LOOKUP_NO_CONVERSION)&~LOOKUP_NO_TEMP_BIND; |
| conversion *new_second |
| = reference_binding (rto, ftype, NULL_TREE, c_cast_p, |
| sflags, complain); |
| if (!new_second) |
| return NULL; |
| return merge_conversion_sequences (t, new_second); |
| } |
| } |
| |
| conv = build_conv (ck_ref_bind, rto, conv); |
| /* This reference binding, unlike those above, requires the |
| creation of a temporary. */ |
| conv->need_temporary_p = true; |
| conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto); |
| |
| /* [dcl.init.ref] |
| |
| Otherwise, the reference shall be an lvalue reference to a |
| non-volatile const type, or the reference shall be an rvalue |
| reference. */ |
| if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto)) |
| conv->bad_p = true; |
| |
| /* [dcl.init.ref] |
| |
| Otherwise, a temporary of type "cv1 T1" is created and |
| initialized from the initializer expression using the rules for a |
| non-reference copy initialization. If T1 is reference-related to |
| T2, cv1 must be the same cv-qualification as, or greater |
| cv-qualification than, cv2; otherwise, the program is ill-formed. */ |
| if (related_p && !at_least_as_qualified_p (to, from)) |
| conv->bad_p = true; |
| |
| return conv; |
| } |
| |
| /* Returns the implicit conversion sequence (see [over.ics]) from type |
| FROM to type TO. The optional expression EXPR may affect the |
| conversion. FLAGS are the usual overloading flags. If C_CAST_P is |
| true, this conversion is coming from a C-style cast. */ |
| |
| static conversion * |
| implicit_conversion (tree to, tree from, tree expr, bool c_cast_p, |
| int flags, tsubst_flags_t complain) |
| { |
| conversion *conv; |
| |
| if (from == error_mark_node || to == error_mark_node |
| || expr == error_mark_node) |
| return NULL; |
| |
| /* Other flags only apply to the primary function in overload |
| resolution, or after we've chosen one. */ |
| flags &= (LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION|LOOKUP_COPY_PARM |
| |LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND|LOOKUP_PREFER_RVALUE |
| |LOOKUP_NO_NARROWING|LOOKUP_PROTECT|LOOKUP_NO_NON_INTEGRAL); |
| |
| /* FIXME: actually we don't want warnings either, but we can't just |
| have 'complain &= ~(tf_warning|tf_error)' because it would cause |
| the regression of, eg, g++.old-deja/g++.benjamin/16077.C. |
| We really ought not to issue that warning until we've committed |
| to that conversion. */ |
| complain &= ~tf_error; |
| |
| /* Call reshape_init early to remove redundant braces. */ |
| if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr) |
| && CLASS_TYPE_P (to) |
| && COMPLETE_TYPE_P (complete_type (to)) |
| && !CLASSTYPE_NON_AGGREGATE (to)) |
| { |
| expr = reshape_init (to, expr, complain); |
| if (expr == error_mark_node) |
| return NULL; |
| from = TREE_TYPE (expr); |
| } |
| |
| if (TYPE_REF_P (to)) |
| conv = reference_binding (to, from, expr, c_cast_p, flags, complain); |
| else |
| conv = standard_conversion (to, from, expr, c_cast_p, flags, complain); |
| |
| if (conv) |
| return conv; |
| |
| if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr)) |
| { |
| if (is_std_init_list (to) && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr)) |
| return build_list_conv (to, expr, flags, complain); |
| |
| /* As an extension, allow list-initialization of _Complex. */ |
| if (TREE_CODE (to) == COMPLEX_TYPE |
| && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr)) |
| { |
| conv = build_complex_conv (to, expr, flags, complain); |
| if (conv) |
| return conv; |
| } |
| |
| /* Allow conversion from an initializer-list with one element to a |
| scalar type. */ |
| if (SCALAR_TYPE_P (to)) |
| { |
| int nelts = CONSTRUCTOR_NELTS (expr); |
| tree elt; |
| |
| if (nelts == 0) |
| elt = build_value_init (to, tf_none); |
| else if (nelts == 1 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr)) |
| elt = CONSTRUCTOR_ELT (expr, 0)->value; |
| else |
| elt = error_mark_node; |
| |
| conv = implicit_conversion (to, TREE_TYPE (elt), elt, |
| c_cast_p, flags, complain); |
| if (conv) |
| { |
| conv->check_narrowing = true; |
| if (BRACE_ENCLOSED_INITIALIZER_P (elt)) |
| /* Too many levels of braces, i.e. '{{1}}'. */ |
| conv->bad_p = true; |
| return conv; |
| } |
| } |
| else if (TREE_CODE (to) == ARRAY_TYPE) |
| return build_array_conv (to, expr, flags, complain); |
| } |
| |
| if (expr != NULL_TREE |
| && (MAYBE_CLASS_TYPE_P (from) |
| || MAYBE_CLASS_TYPE_P (to)) |
| && (flags & LOOKUP_NO_CONVERSION) == 0) |
| { |
| struct z_candidate *cand; |
| |
| if (CLASS_TYPE_P (to) |
| && BRACE_ENCLOSED_INITIALIZER_P (expr) |
| && !CLASSTYPE_NON_AGGREGATE (complete_type (to))) |
| return build_aggr_conv (to, expr, flags, complain); |
| |
| cand = build_user_type_conversion_1 (to, expr, flags, complain); |
| if (cand) |
| { |
| if (BRACE_ENCLOSED_INITIALIZER_P (expr) |
| && CONSTRUCTOR_NELTS (expr) == 1 |
| && !is_list_ctor (cand->fn)) |
| { |
| /* "If C is not an initializer-list constructor and the |
| initializer list has a single element of type cv U, where U is |
| X or a class derived from X, the implicit conversion sequence |
| has Exact Match rank if U is X, or Conversion rank if U is |
| derived from X." */ |
| tree elt = CONSTRUCTOR_ELT (expr, 0)->value; |
| tree elttype = TREE_TYPE (elt); |
| if (reference_related_p (to, elttype)) |
| return implicit_conversion (to, elttype, elt, |
| c_cast_p, flags, complain); |
| } |
| conv = cand->second_conv; |
| } |
| |
| /* We used to try to bind a reference to a temporary here, but that |
| is now handled after the recursive call to this function at the end |
| of reference_binding. */ |
| return conv; |
| } |
| |
| return NULL; |
| } |
| |
| /* Like implicit_conversion, but return NULL if the conversion is bad. |
| |
| This is not static so that check_non_deducible_conversion can call it within |
| add_template_candidate_real as part of overload resolution; it should not be |
| called outside of overload resolution. */ |
| |
| conversion * |
| good_conversion (tree to, tree from, tree expr, |
| int flags, tsubst_flags_t complain) |
| { |
| conversion *c = implicit_conversion (to, from, expr, /*cast*/false, |
| flags, complain); |
| if (c && c->bad_p) |
| c = NULL; |
| return c; |
| } |
| |
| /* Add a new entry to the list of candidates. Used by the add_*_candidate |
| functions. ARGS will not be changed until a single candidate is |
| selected. */ |
| |
| static struct z_candidate * |
| add_candidate (struct z_candidate **candidates, |
| tree fn, tree first_arg, const vec<tree, va_gc> *args, |
| size_t num_convs, conversion **convs, |
| tree access_path, tree conversion_path, |
| int viable, struct rejection_reason *reason, |
| int flags) |
| { |
| struct z_candidate *cand = (struct z_candidate *) |
| conversion_obstack_alloc (sizeof (struct z_candidate)); |
| |
| cand->fn = fn; |
| cand->first_arg = first_arg; |
| cand->args = args; |
| cand->convs = convs; |
| cand->num_convs = num_convs; |
| cand->access_path = access_path; |
| cand->conversion_path = conversion_path; |
| cand->viable = viable; |
| cand->reason = reason; |
| cand->next = *candidates; |
| cand->flags = flags; |
| *candidates = cand; |
| |
| if (convs && cand->reversed ()) |
| /* Swap the conversions for comparison in joust; we'll swap them back |
| before build_over_call. */ |
| std::swap (convs[0], convs[1]); |
| |
| return cand; |
| } |
| |
| /* Return the number of remaining arguments in the parameter list |
| beginning with ARG. */ |
| |
| int |
| remaining_arguments (tree arg) |
| { |
| int n; |
| |
| for (n = 0; arg != NULL_TREE && arg != void_list_node; |
| arg = TREE_CHAIN (arg)) |
| n++; |
| |
| return n; |
| } |
| |
| /* [over.match.copy]: When initializing a temporary object (12.2) to be bound |
| to the first parameter of a constructor where the parameter is of type |
| "reference to possibly cv-qualified T" and the constructor is called with a |
| single argument in the context of direct-initialization of an object of type |
| "cv2 T", explicit conversion functions are also considered. |
| |
| So set LOOKUP_COPY_PARM to let reference_binding know that |
| it's being called in that context. */ |
| |
| int |
| conv_flags (int i, int nargs, tree fn, tree arg, int flags) |
| { |
| int lflags = flags; |
| tree t; |
| if (i == 0 && nargs == 1 && DECL_CONSTRUCTOR_P (fn) |
| && (t = FUNCTION_FIRST_USER_PARMTYPE (fn)) |
| && (same_type_ignoring_top_level_qualifiers_p |
| (non_reference (TREE_VALUE (t)), DECL_CONTEXT (fn)))) |
| { |
| if (!(flags & LOOKUP_ONLYCONVERTING)) |
| lflags |= LOOKUP_COPY_PARM; |
| if ((flags & LOOKUP_LIST_INIT_CTOR) |
| && BRACE_ENCLOSED_INITIALIZER_P (arg)) |
| lflags |= LOOKUP_NO_CONVERSION; |
| } |
| else |
| lflags |= LOOKUP_ONLYCONVERTING; |
| |
| return lflags; |
| } |
| |
| /* Create an overload candidate for the function or method FN called |
| with the argument list FIRST_ARG/ARGS and add it to CANDIDATES. |
| FLAGS is passed on to implicit_conversion. |
| |
| This does not change ARGS. |
| |
| CTYPE, if non-NULL, is the type we want to pretend this function |
| comes from for purposes of overload resolution. */ |
| |
| static struct z_candidate * |
| add_function_candidate (struct z_candidate **candidates, |
| tree fn, tree ctype, tree first_arg, |
| const vec<tree, va_gc> *args, tree access_path, |
| tree conversion_path, int flags, |
| conversion **convs, |
| tsubst_flags_t complain) |
| { |
| tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn)); |
| int i, len; |
| tree parmnode; |
| tree orig_first_arg = first_arg; |
| int skip; |
| int viable = 1; |
| struct rejection_reason *reason = NULL; |
| |
| /* At this point we should not see any functions which haven't been |
| explicitly declared, except for friend functions which will have |
| been found using argument dependent lookup. */ |
| gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn)); |
| |
| /* The `this', `in_chrg' and VTT arguments to constructors are not |
| considered in overload resolution. */ |
| if (DECL_CONSTRUCTOR_P (fn)) |
| { |
| if (ctor_omit_inherited_parms (fn)) |
| /* Bring back parameters omitted from an inherited ctor. */ |
| parmlist = FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn)); |
| else |
| parmlist = skip_artificial_parms_for (fn, parmlist); |
| skip = num_artificial_parms_for (fn); |
| if (skip > 0 && first_arg != NULL_TREE) |
| { |
| --skip; |
| first_arg = NULL_TREE; |
| } |
| } |
| else |
| skip = 0; |
| |
| len = vec_safe_length (args) - skip + (first_arg != NULL_TREE ? 1 : 0); |
| if (!convs) |
| convs = alloc_conversions (len); |
| |
| /* 13.3.2 - Viable functions [over.match.viable] |
| First, to be a viable function, a candidate function shall have enough |
| parameters to agree in number with the arguments in the list. |
| |
| We need to check this first; otherwise, checking the ICSes might cause |
| us to produce an ill-formed template instantiation. */ |
| |
| parmnode = parmlist; |
| for (i = 0; i < len; ++i) |
| { |
| if (parmnode == NULL_TREE || parmnode == void_list_node) |
| break; |
| parmnode = TREE_CHAIN (parmnode); |
| } |
| |
| if ((i < len && parmnode) |
| || !sufficient_parms_p (parmnode)) |
| { |
| int remaining = remaining_arguments (parmnode); |
| viable = 0; |
| reason = arity_rejection (first_arg, i + remaining, len); |
| } |
| |
| /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first |
| parameter of type "reference to cv C" (including such a constructor |
| instantiated from a template) is excluded from the set of candidate |
| functions when used to construct an object of type D with an argument list |
| containing a single argument if C is reference-related to D. */ |
| if (viable && len == 1 && parmlist && DECL_CONSTRUCTOR_P (fn) |
| && flag_new_inheriting_ctors |
| && DECL_INHERITED_CTOR (fn)) |
| { |
| tree ptype = non_reference (TREE_VALUE (parmlist)); |
| tree dtype = DECL_CONTEXT (fn); |
| tree btype = DECL_INHERITED_CTOR_BASE (fn); |
| if (reference_related_p (ptype, dtype) |
| && reference_related_p (btype, ptype)) |
| { |
| viable = false; |
| reason = inherited_ctor_rejection (); |
| } |
| } |
| |
| /* Second, for a function to be viable, its constraints must be |
| satisfied. */ |
| if (flag_concepts && viable && !constraints_satisfied_p (fn)) |
| { |
| reason = constraint_failure (); |
| viable = false; |
| } |
| |
| /* When looking for a function from a subobject from an implicit |
| copy/move constructor/operator=, don't consider anything that takes (a |
| reference to) an unrelated type. See c++/44909 and core 1092. */ |
| if (viable && parmlist && (flags & LOOKUP_DEFAULTED)) |
| { |
| if (DECL_CONSTRUCTOR_P (fn)) |
| i = 1; |
| else if (DECL_ASSIGNMENT_OPERATOR_P (fn) |
| && DECL_OVERLOADED_OPERATOR_IS (fn, NOP_EXPR)) |
| i = 2; |
| else |
| i = 0; |
| if (i && len == i) |
| { |
| parmnode = chain_index (i-1, parmlist); |
| if (!reference_related_p (non_reference (TREE_VALUE (parmnode)), |
| ctype)) |
| viable = 0; |
| } |
| |
| /* This only applies at the top level. */ |
| flags &= ~LOOKUP_DEFAULTED; |
| } |
| |
| if (! viable) |
| goto out; |
| |
| /* Third, for F to be a viable function, there shall exist for each |
| argument an implicit conversion sequence that converts that argument |
| to the corresponding parameter of F. */ |
| |
| parmnode = parmlist; |
| |
| for (i = 0; i < len; ++i) |
| { |
| tree argtype, to_type; |
| tree arg; |
| conversion *t; |
| int is_this; |
| |
| if (parmnode == void_list_node) |
| break; |
| |
| if (convs[i]) |
| { |
| /* Already set during deduction. */ |
| parmnode = TREE_CHAIN (parmnode); |
| continue; |
| } |
| |
| if (i == 0 && first_arg != NULL_TREE) |
| arg = first_arg; |
| else |
| arg = CONST_CAST_TREE ( |
| (*args)[i + skip - (first_arg != NULL_TREE ? 1 : 0)]); |
| argtype = lvalue_type (arg); |
| |
| is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn) |
| && ! DECL_CONSTRUCTOR_P (fn)); |
| |
| if (parmnode) |
| { |
| tree parmtype = TREE_VALUE (parmnode); |
| |
| parmnode = TREE_CHAIN (parmnode); |
| |
| /* The type of the implicit object parameter ('this') for |
| overload resolution is not always the same as for the |
| function itself; conversion functions are considered to |
| be members of the class being converted, and functions |
| introduced by a using-declaration are considered to be |
| members of the class that uses them. |
| |
| Since build_over_call ignores the ICS for the `this' |
| parameter, we can just change the parm type. */ |
| if (ctype && is_this) |
| { |
| parmtype = cp_build_qualified_type |
| (ctype, cp_type_quals (TREE_TYPE (parmtype))); |
| if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn))) |
| { |
| /* If the function has a ref-qualifier, the implicit |
| object parameter has reference type. */ |
| bool rv = FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn)); |
| parmtype = cp_build_reference_type (parmtype, rv); |
| /* The special handling of 'this' conversions in compare_ics |
| does not apply if there is a ref-qualifier. */ |
| is_this = false; |
| } |
| else |
| { |
| parmtype = build_pointer_type (parmtype); |
| /* We don't use build_this here because we don't want to |
| capture the object argument until we've chosen a |
| non-static member function. */ |
| arg = build_address (arg); |
| argtype = lvalue_type (arg); |
| } |
| } |
| |
| int lflags = conv_flags (i, len-skip, fn, arg, flags); |
| |
| t = implicit_conversion (parmtype, argtype, arg, |
| /*c_cast_p=*/false, lflags, complain); |
| to_type = parmtype; |
| } |
| else |
| { |
| t = build_identity_conv (argtype, arg); |
| t->ellipsis_p = true; |
| to_type = argtype; |
| } |
| |
| if (t && is_this) |
| t->this_p = true; |
| |
| convs[i] = t; |
| if (! t) |
| { |
| viable = 0; |
| reason = arg_conversion_rejection (first_arg, i, argtype, to_type, |
| EXPR_LOCATION (arg)); |
| break; |
| } |
| |
| if (t->bad_p) |
| { |
| viable = -1; |
| reason = bad_arg_conversion_rejection (first_arg, i, arg, to_type, |
| EXPR_LOCATION (arg)); |
| |
| } |
| } |
| |
| out: |
| return add_candidate (candidates, fn, orig_first_arg, args, len, convs, |
| access_path, conversion_path, viable, reason, flags); |
| } |
| |
| /* Create an overload candidate for the conversion function FN which will |
| be invoked for expression OBJ, producing a pointer-to-function which |
| will in turn be called with the argument list FIRST_ARG/ARGLIST, |
| and add it to CANDIDATES. This does not change ARGLIST. FLAGS is |
| passed on to implicit_conversion. |
| |
| Actually, we don't really care about FN; we care about the type it |
| converts to. There may be multiple conversion functions that will |
| convert to that type, and we rely on build_user_type_conversion_1 to |
| choose the best one; so when we create our candidate, we record the type |
| instead of the function. */ |
| |
| static struct z_candidate * |
| add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj, |
| const vec<tree, va_gc> *arglist, |
| tree access_path, tree conversion_path, |
| tsubst_flags_t complain) |
| { |
| tree totype = TREE_TYPE (TREE_TYPE (fn)); |
| int i, len, viable, flags; |
| tree parmlist, parmnode; |
| conversion **convs; |
| struct rejection_reason *reason; |
| |
| for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; ) |
| parmlist = TREE_TYPE (parmlist); |
| parmlist = TYPE_ARG_TYPES (parmlist); |
| |
| len = vec_safe_length (arglist) + 1; |
| convs = alloc_conversions (len); |
| parmnode = parmlist; |
| viable = 1; |
| flags = LOOKUP_IMPLICIT; |
| reason = NULL; |
| |
| /* Don't bother looking up the same type twice. */ |
| if (*candidates && (*candidates)->fn == totype) |
| return NULL; |
| |
| for (i = 0; i < len; ++i) |
| { |
| tree arg, argtype, convert_type = NULL_TREE; |
| conversion *t; |
| |
| if (i == 0) |
| arg = obj; |
| else |
| arg = (*arglist)[i - 1]; |
| argtype = lvalue_type (arg); |
| |
| if (i == 0) |
| { |
| t = build_identity_conv (argtype, NULL_TREE); |
| t = build_conv (ck_user, totype, t); |
| /* Leave the 'cand' field null; we'll figure out the conversion in |
| convert_like_real if this candidate is chosen. */ |
| convert_type = totype; |
| } |
| else if (parmnode == void_list_node) |
| break; |
| else if (parmnode) |
| { |
| t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, |
| /*c_cast_p=*/false, flags, complain); |
| convert_type = TREE_VALUE (parmnode); |
| } |
| else |
| { |
| t = build_identity_conv (argtype, arg); |
| t->ellipsis_p = true; |
| convert_type = argtype; |
| } |
| |
| convs[i] = t; |
| if (! t) |
| break; |
| |
| if (t->bad_p) |
| { |
| viable = -1; |
| reason = bad_arg_conversion_rejection (NULL_TREE, i, arg, convert_type, |
| EXPR_LOCATION (arg)); |
| } |
| |
| if (i == 0) |
| continue; |
| |
| if (parmnode) |
| parmnode = TREE_CHAIN (parmnode); |
| } |
| |
| if (i < len |
| || ! sufficient_parms_p (parmnode)) |
| { |
| int remaining = remaining_arguments (parmnode); |
| viable = 0; |
| reason = arity_rejection (NULL_TREE, i + remaining, len); |
| } |
| |
| return add_candidate (candidates, totype, obj, arglist, len, convs, |
| access_path, conversion_path, viable, reason, flags); |
| } |
| |
| static void |
| build_builtin_candidate (struct z_candidate **candidates, tree fnname, |
| tree type1, tree type2, const vec<tree,va_gc> &args, |
| tree *argtypes, int flags, tsubst_flags_t complain) |
| { |
| conversion *t; |
| conversion **convs; |
| size_t num_convs; |
| int viable = 1; |
| tree types[2]; |
| struct rejection_reason *reason = NULL; |
| |
| types[0] = type1; |
| types[1] = type2; |
| |
| num_convs = args.length (); |
| convs = alloc_conversions (num_convs); |
| |
| /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit |
| conversion ops are allowed. We handle that here by just checking for |
| boolean_type_node because other operators don't ask for it. COND_EXPR |
| also does contextual conversion to bool for the first operand, but we |
| handle that in build_conditional_expr, and type1 here is operand 2. */ |
| if (type1 != boolean_type_node) |
| flags |= LOOKUP_ONLYCONVERTING; |
| |
| for (unsigned i = 0; i < 2 && i < num_convs; ++i) |
| { |
| t = implicit_conversion (types[i], argtypes[i], args[i], |
| /*c_cast_p=*/false, flags, complain); |
| if (! t) |
| { |
| viable = 0; |
| /* We need something for printing the candidate. */ |
| t = build_identity_conv (types[i], NULL_TREE); |
| reason = arg_conversion_rejection (NULL_TREE, i, argtypes[i], |
| types[i], EXPR_LOCATION (args[i])); |
| } |
| else if (t->bad_p) |
| { |
| viable = 0; |
| reason = bad_arg_conversion_rejection (NULL_TREE, i, args[i], |
| types[i], |
| EXPR_LOCATION (args[i])); |
| } |
| convs[i] = t; |
| } |
| |
| /* For COND_EXPR we rearranged the arguments; undo that now. */ |
| if (num_convs == 3) |
| { |
| convs[2] = convs[1]; |
| convs[1] = convs[0]; |
| t = implicit_conversion (boolean_type_node, argtypes[2], args[2], |
| /*c_cast_p=*/false, flags, |
| complain); |
| if (t) |
| convs[0] = t; |
| else |
| { |
| viable = 0; |
| reason = arg_conversion_rejection (NULL_TREE, 0, argtypes[2], |
| boolean_type_node, |
| EXPR_LOCATION (args[2])); |
| } |
| } |
| |
| add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL, |
| num_convs, convs, |
| /*access_path=*/NULL_TREE, |
| /*conversion_path=*/NULL_TREE, |
| viable, reason, flags); |
| } |
| |
| static bool |
| is_complete (tree t) |
| { |
| return COMPLETE_TYPE_P (complete_type (t)); |
| } |
| |
| /* Returns nonzero if TYPE is a promoted arithmetic type. */ |
| |
| static bool |
| promoted_arithmetic_type_p (tree type) |
| { |
| /* [over.built] |
| |
| In this section, the term promoted integral type is used to refer |
| to those integral types which are preserved by integral promotion |
| (including e.g. int and long but excluding e.g. char). |
| Similarly, the term promoted arithmetic type refers to promoted |
| integral types plus floating types. */ |
| return ((CP_INTEGRAL_TYPE_P (type) |
| && same_type_p (type_promotes_to (type), type)) |
| || TREE_CODE (type) == REAL_TYPE); |
| } |
| |
| /* Create any builtin operator overload candidates for the operator in |
| question given the converted operand types TYPE1 and TYPE2. The other |
| args are passed through from add_builtin_candidates to |
| build_builtin_candidate. |
| |
| TYPE1 and TYPE2 may not be permissible, and we must filter them. |
| If CODE is requires candidates operands of the same type of the kind |
| of which TYPE1 and TYPE2 are, we add both candidates |
| CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */ |
| |
| static void |
| add_builtin_candidate (struct z_candidate **candidates, enum tree_code code, |
| enum tree_code code2, tree fnname, tree type1, |
| tree type2, vec<tree,va_gc> &args, tree *argtypes, |
| int flags, tsubst_flags_t complain) |
| { |
| switch (code) |
| { |
| case POSTINCREMENT_EXPR: |
| case POSTDECREMENT_EXPR: |
| args[1] = integer_zero_node; |
| type2 = integer_type_node; |
| break; |
| default: |
| break; |
| } |
| |
| switch (code) |
| { |
| |
| /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type, |
| and VQ is either volatile or empty, there exist candidate operator |
| functions of the form |
| VQ T& operator++(VQ T&); |
| T operator++(VQ T&, int); |
| 5 For every pair T, VQ), where T is an enumeration type or an arithmetic |
| type other than bool, and VQ is either volatile or empty, there exist |
| candidate operator functions of the form |
| VQ T& operator--(VQ T&); |
| T operator--(VQ T&, int); |
| 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified |
| complete object type, and VQ is either volatile or empty, there exist |
| candidate operator functions of the form |
| T*VQ& operator++(T*VQ&); |
| T*VQ& operator--(T*VQ&); |
| T* operator++(T*VQ&, int); |
| T* operator--(T*VQ&, int); */ |
| |
| case POSTDECREMENT_EXPR: |
| case PREDECREMENT_EXPR: |
| if (TREE_CODE (type1) == BOOLEAN_TYPE) |
| return; |
| /* FALLTHRU */ |
| case POSTINCREMENT_EXPR: |
| case PREINCREMENT_EXPR: |
| if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1)) |
| { |
| type1 = build_reference_type (type1); |
| break; |
| } |
| return; |
| |
| /* 7 For every cv-qualified or cv-unqualified object type T, there |
| exist candidate operator functions of the form |
| |
| T& operator*(T*); |
| |
| 8 For every function type T, there exist candidate operator functions of |
| the form |
| T& operator*(T*); */ |
| |
| case INDIRECT_REF: |
| if (TYPE_PTR_P (type1) |
| && (TYPE_PTROB_P (type1) |
| || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)) |
| break; |
| return; |
| |
| /* 9 For every type T, there exist candidate operator functions of the form |
| T* operator+(T*); |
| |
| 10For every promoted arithmetic type T, there exist candidate operator |
| functions of the form |
| T operator+(T); |
| T operator-(T); */ |
| |
| case UNARY_PLUS_EXPR: /* unary + */ |
| if (TYPE_PTR_P (type1)) |
| break; |
| /* FALLTHRU */ |
| case NEGATE_EXPR: |
| if (ARITHMETIC_TYPE_P (type1)) |
| break; |
| return; |
| |
| /* 11For every promoted integral type T, there exist candidate operator |
| functions of the form |
| T operator~(T); */ |
| |
| case BIT_NOT_EXPR: |
| if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1)) |
| break; |
| return; |
| |
| /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1 |
| is the same type as C2 or is a derived class of C2, T is a complete |
| object type or a function type, and CV1 and CV2 are cv-qualifier-seqs, |
| there exist candidate operator functions of the form |
| CV12 T& operator->*(CV1 C1*, CV2 T C2::*); |
| where CV12 is the union of CV1 and CV2. */ |
| |
| case MEMBER_REF: |
| if (TYPE_PTR_P (type1) && TYPE_PTRMEM_P (type2)) |
| { |
| tree c1 = TREE_TYPE (type1); |
| tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2); |
| |
| if (CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1) |
| && (TYPE_PTRMEMFUNC_P (type2) |
| || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2)))) |
| break; |
| } |
| return; |
| |
| /* 13For every pair of promoted arithmetic types L and R, there exist can- |
| didate operator functions of the form |
| LR operator*(L, R); |
| LR operator/(L, R); |
| LR operator+(L, R); |
| LR operator-(L, R); |
| bool operator<(L, R); |
| bool operator>(L, R); |
| bool operator<=(L, R); |
| bool operator>=(L, R); |
| bool operator==(L, R); |
| bool operator!=(L, R); |
| where LR is the result of the usual arithmetic conversions between |
| types L and R. |
| |
| For every integral type T there exists a candidate operator function of |
| the form |
| |
| std::strong_ordering operator<=>(T, T); |
| |
| For every pair of floating-point types L and R, there exists a candidate |
| operator function of the form |
| |
| std::partial_ordering operator<=>(L, R); |
| |
| 14For every pair of types T and I, where T is a cv-qualified or cv- |
| unqualified complete object type and I is a promoted integral type, |
| there exist candidate operator functions of the form |
| T* operator+(T*, I); |
| T& operator[](T*, I); |
| T* operator-(T*, I); |
| T* operator+(I, T*); |
| T& operator[](I, T*); |
| |
| 15For every T, where T is a pointer to complete object type, there exist |
| candidate operator functions of the form112) |
| ptrdiff_t operator-(T, T); |
| |
| 16For every pointer or enumeration type T, there exist candidate operator |
| functions of the form |
| bool operator<(T, T); |
| bool operator>(T, T); |
| bool operator<=(T, T); |
| bool operator>=(T, T); |
| bool operator==(T, T); |
| bool operator!=(T, T); |
| R operator<=>(T, T); |
| |
| where R is the result type specified in [expr.spaceship]. |
| |
| 17For every pointer to member type T, there exist candidate operator |
| functions of the form |
| bool operator==(T, T); |
| bool operator!=(T, T); |
| std::strong_equality operator<=>(T, T); */ |
| |
| case MINUS_EXPR: |
| if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2)) |
| break; |
| if (TYPE_PTROB_P (type1) |
| && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2)) |
| { |
| type2 = ptrdiff_type_node; |
| break; |
| } |
| /* FALLTHRU */ |
| case MULT_EXPR: |
| case TRUNC_DIV_EXPR: |
| if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) |
| break; |
| return; |
| |
| /* This isn't exactly what's specified above for operator<=>, but it's |
| close enough. In particular, we don't care about the return type |
| specified above; it doesn't participate in overload resolution and it |
| doesn't affect the semantics of the built-in operator. */ |
| case SPACESHIP_EXPR: |
| case EQ_EXPR: |
| case NE_EXPR: |
| if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2)) |
| || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2))) |
| break; |
| if (TYPE_PTRMEM_P (type1) && null_ptr_cst_p (args[1])) |
| { |
| type2 = type1; |
| break; |
| } |
| if (TYPE_PTRMEM_P (type2) && null_ptr_cst_p (args[0])) |
| { |
| type1 = type2; |
| break; |
| } |
| /* Fall through. */ |
| case LT_EXPR: |
| case GT_EXPR: |
| case LE_EXPR: |
| case GE_EXPR: |
| case MAX_EXPR: |
| case MIN_EXPR: |
| if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) |
| break; |
| if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2)) |
| break; |
| if (TREE_CODE (type1) == ENUMERAL_TYPE |
| && TREE_CODE (type2) == ENUMERAL_TYPE) |
| break; |
| if (TYPE_PTR_P (type1) |
| && null_ptr_cst_p (args[1])) |
| { |
| type2 = type1; |
| break; |
| } |
| if (null_ptr_cst_p (args[0]) |
| && TYPE_PTR_P (type2)) |
| { |
| type1 = type2; |
| break; |
| } |
| return; |
| |
| case PLUS_EXPR: |
| if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) |
| break; |
| /* FALLTHRU */ |
| case ARRAY_REF: |
| if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2)) |
| { |
| type1 = ptrdiff_type_node; |
| break; |
| } |
| if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2)) |
| { |
| type2 = ptrdiff_type_node; |
| break; |
| } |
| return; |
| |
| /* 18For every pair of promoted integral types L and R, there exist candi- |
| date operator functions of the form |
| LR operator%(L, R); |
| LR operator&(L, R); |
| LR operator^(L, R); |
| LR operator|(L, R); |
| L operator<<(L, R); |
| L operator>>(L, R); |
| where LR is the result of the usual arithmetic conversions between |
| types L and R. */ |
| |
| case TRUNC_MOD_EXPR: |
| case BIT_AND_EXPR: |
| case BIT_IOR_EXPR: |
| case BIT_XOR_EXPR: |
| case LSHIFT_EXPR: |
| case RSHIFT_EXPR: |
| if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2)) |
| break; |
| return; |
| |
| /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration |
| type, VQ is either volatile or empty, and R is a promoted arithmetic |
| type, there exist candidate operator functions of the form |
| VQ L& operator=(VQ L&, R); |
| VQ L& operator*=(VQ L&, R); |
| VQ L& operator/=(VQ L&, R); |
| VQ L& operator+=(VQ L&, R); |
| VQ L& operator-=(VQ L&, R); |
| |
| 20For every pair T, VQ), where T is any type and VQ is either volatile |
| or empty, there exist candidate operator functions of the form |
| T*VQ& operator=(T*VQ&, T*); |
| |
| 21For every pair T, VQ), where T is a pointer to member type and VQ is |
| either volatile or empty, there exist candidate operator functions of |
| the form |
| VQ T& operator=(VQ T&, T); |
| |
| 22For every triple T, VQ, I), where T is a cv-qualified or cv- |
| unqualified complete object type, VQ is either volatile or empty, and |
| I is a promoted integral type, there exist candidate operator func- |
| tions of the form |
| T*VQ& operator+=(T*VQ&, I); |
| T*VQ& operator-=(T*VQ&, I); |
| |
| 23For every triple L, VQ, R), where L is an integral or enumeration |
| type, VQ is either volatile or empty, and R is a promoted integral |
| type, there exist candidate operator functions of the form |
| |
| VQ L& operator%=(VQ L&, R); |
| VQ L& operator<<=(VQ L&, R); |
| VQ L& operator>>=(VQ L&, R); |
| VQ L& operator&=(VQ L&, R); |
| VQ L& operator^=(VQ L&, R); |
| VQ L& operator|=(VQ L&, R); */ |
| |
| case MODIFY_EXPR: |
| switch (code2) |
| { |
| case PLUS_EXPR: |
| case MINUS_EXPR: |
| if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2)) |
| { |
| type2 = ptrdiff_type_node; |
| break; |
| } |
| /* FALLTHRU */ |
| case MULT_EXPR: |
| case TRUNC_DIV_EXPR: |
| if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) |
| break; |
| return; |
| |
| case TRUNC_MOD_EXPR: |
| case BIT_AND_EXPR: |
| case BIT_IOR_EXPR: |
| case BIT_XOR_EXPR: |
| case LSHIFT_EXPR: |
| case RSHIFT_EXPR: |
| if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2)) |
| break; |
| return; |
| |
| case NOP_EXPR: |
| if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2)) |
| break; |
| if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2)) |
| || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2)) |
| || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2)) |
| || ((TYPE_PTRMEMFUNC_P (type1) |
| || TYPE_PTR_P (type1)) |
| && null_ptr_cst_p (args[1]))) |
| { |
| type2 = type1; |
| break; |
| } |
| return; |
| |
| default: |
| gcc_unreachable (); |
| } |
| type1 = build_reference_type (type1); |
| break; |
| |
| case COND_EXPR: |
| /* [over.built] |
| |
| For every pair of promoted arithmetic types L and R, there |
| exist candidate operator functions of the form |
| |
| LR operator?(bool, L, R); |
| |
| where LR is the result of the usual arithmetic conversions |
| between types L and R. |
| |
| For every type T, where T is a pointer or pointer-to-member |
| type, there exist candidate operator functions of the form T |
| operator?(bool, T, T); */ |
| |
| if (promoted_arithmetic_type_p (type1) |
| && promoted_arithmetic_type_p (type2)) |
| /* That's OK. */ |
| break; |
| |
| /* Otherwise, the types should be pointers. */ |
| if (!TYPE_PTR_OR_PTRMEM_P (type1) || !TYPE_PTR_OR_PTRMEM_P (type2)) |
| return; |
| |
| /* We don't check that the two types are the same; the logic |
| below will actually create two candidates; one in which both |
| parameter types are TYPE1, and one in which both parameter |
| types are TYPE2. */ |
| break; |
| |
| case REALPART_EXPR: |
| case IMAGPART_EXPR: |
| if (ARITHMETIC_TYPE_P (type1)) |
| break; |
| return; |
| |
| default: |
| gcc_unreachable (); |
| } |
| |
| /* Make sure we don't create builtin candidates with dependent types. */ |
| bool u1 = uses_template_parms (type1); |
| bool u2 = type2 ? uses_template_parms (type2) : false; |
| if (u1 || u2) |
| { |
| /* Try to recover if one of the types is non-dependent. But if |
| there's only one type, there's nothing we can do. */ |
| if (!type2) |
| return; |
| /* And we lose if both are dependent. */ |
| if (u1 && u2) |
| return; |
| /* Or if they have different forms. */ |
| if (TREE_CODE (type1) != TREE_CODE (type2)) |
| return; |
| |
| if (u1 && !u2) |
| type1 = type2; |
| else if (u2 && !u1) |
| type2 = type1; |
| } |
| |
| /* If we're dealing with two pointer types or two enumeral types, |
| we need candidates for both of them. */ |
| if (type2 && !same_type_p (type1, type2) |
| && TREE_CODE (type1) == TREE_CODE (type2) |
| && (TYPE_REF_P (type1) |
| || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2)) |
| || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2)) |
| || TYPE_PTRMEMFUNC_P (type1) |
| || MAYBE_CLASS_TYPE_P (type1) |
| || TREE_CODE (type1) == ENUMERAL_TYPE)) |
| { |
| if (TYPE_PTR_OR_PTRMEM_P (type1)) |
| { |
| tree cptype = composite_pointer_type (input_location, |
| type1, type2, |
| error_mark_node, |
| error_mark_node, |
| CPO_CONVERSION, |
| tf_none); |
| if (cptype != error_mark_node) |
| { |
| build_builtin_candidate |
| (candidates, fnname, cptype, cptype, args, argtypes, |
| flags, complain); |
| return; |
| } |
| } |
| |
| build_builtin_candidate |
| (candidates, fnname, type1, type1, args, argtypes, flags, complain); |
| build_builtin_candidate |
| (candidates, fnname, type2, type2, args, argtypes, flags, complain); |
| return; |
| } |
| |
| build_builtin_candidate |
| (candidates, fnname, type1, type2, args, argtypes, flags, complain); |
| } |
| |
| tree |
| type_decays_to (tree type) |
| { |
| if (TREE_CODE (type) == ARRAY_TYPE) |
| return build_pointer_type (TREE_TYPE (type)); |
| if (TREE_CODE (type) == FUNCTION_TYPE) |
| return build_pointer_type (type); |
| return type; |
| } |
| |
| /* There are three conditions of builtin candidates: |
| |
| 1) bool-taking candidates. These are the same regardless of the input. |
| 2) pointer-pair taking candidates. These are generated for each type |
| one of the input types converts to. |
| 3) arithmetic candidates. According to the standard, we should generate |
| all of these, but I'm trying not to... |
| |
| Here we generate a superset of the possible candidates for this particular |
| case. That is a subset of the full set the standard defines, plus some |
| other cases which the standard disallows. add_builtin_candidate will |
| filter out the invalid set. */ |
| |
| static void |
| add_builtin_candidates (struct z_candidate **candidates, enum tree_code code, |
| enum tree_code code2, tree fnname, |
| vec<tree, va_gc> *argv, |
| int flags, tsubst_flags_t complain) |
| { |
| int ref1; |
| int enum_p = 0; |
| tree type, argtypes[3], t; |
| /* TYPES[i] is the set of possible builtin-operator parameter types |
| we will consider for the Ith argument. */ |
| vec<tree, va_gc> *types[2]; |
| unsigned ix; |
| vec<tree, va_gc> &args = *argv; |
| unsigned len = args.length (); |
| |
| for (unsigned i = 0; i < len; ++i) |
| { |
| if (args[i]) |
| argtypes[i] = unlowered_expr_type (args[i]); |
| else |
| argtypes[i] = NULL_TREE; |
| } |
| |
| switch (code) |
| { |
| /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type, |
| and VQ is either volatile or empty, there exist candidate operator |
| functions of the form |
| VQ T& operator++(VQ T&); */ |
| |
| case POSTINCREMENT_EXPR: |
| case PREINCREMENT_EXPR: |
| case POSTDECREMENT_EXPR: |
| case PREDECREMENT_EXPR: |
| case MODIFY_EXPR: |
| ref1 = 1; |
| break; |
| |
| /* 24There also exist candidate operator functions of the form |
| bool operator!(bool); |
| bool operator&&(bool, bool); |
| bool operator||(bool, bool); */ |
| |
| case TRUTH_NOT_EXPR: |
| build_builtin_candidate |
| (candidates, fnname, boolean_type_node, |
| NULL_TREE, args, argtypes, flags, complain); |
| return; |
| |
| case TRUTH_ORIF_EXPR: |
| case TRUTH_ANDIF_EXPR: |
| build_builtin_candidate |
| (candidates, fnname, boolean_type_node, |
| boolean_type_node, args, argtypes, flags, complain); |
| return; |
| |
| case ADDR_EXPR: |
| case COMPOUND_EXPR: |
| case COMPONENT_REF: |
| case CO_AWAIT_EXPR: |
| return; |
| |
| case COND_EXPR: |
| case EQ_EXPR: |
| case NE_EXPR: |
| case LT_EXPR: |
| case LE_EXPR: |
| case GT_EXPR: |
| case GE_EXPR: |
| case SPACESHIP_EXPR: |
| enum_p = 1; |
| /* Fall through. */ |
| |
| default: |
| ref1 = 0; |
| } |
| |
| types[0] = make_tree_vector (); |
| types[1] = make_tree_vector (); |
| |
| if (len == 3) |
| len = 2; |
| for (unsigned i = 0; i < len; ++i) |
| { |
| if (MAYBE_CLASS_TYPE_P (argtypes[i])) |
| { |
| tree convs; |
| |
| if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR) |
| return; |
| |
| convs = lookup_conversions (argtypes[i]); |
| |
| if (code == COND_EXPR) |
| { |
| if (lvalue_p (args[i])) |
| vec_safe_push (types[i], build_reference_type (argtypes[i])); |
| |
| vec_safe_push (types[i], TYPE_MAIN_VARIANT (argtypes[i])); |
| } |
| |
| else if (! convs) |
| return; |
| |
| for (; convs; convs = TREE_CHAIN (convs)) |
| { |
| type = TREE_TYPE (convs); |
| |
| if (i == 0 && ref1 |
| && (!TYPE_REF_P (type) |
| || CP_TYPE_CONST_P (TREE_TYPE (type)))) |
| continue; |
| |
| if (code == COND_EXPR && TYPE_REF_P (type)) |
| vec_safe_push (types[i], type); |
| |
| type = non_reference (type); |
| if (i != 0 || ! ref1) |
| { |
| type = cv_unqualified (type_decays_to (type)); |
| if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE) |
| vec_safe_push (types[i], type); |
| if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type)) |
| type = type_promotes_to (type); |
| } |
| |
| if (! vec_member (type, types[i])) |
| vec_safe_push (types[i], type); |
| } |
| } |
| else |
| { |
| if (code == COND_EXPR && lvalue_p (args[i])) |
| vec_safe_push (types[i], build_reference_type (argtypes[i])); |
| type = non_reference (argtypes[i]); |
| if (i != 0 || ! ref1) |
| { |
| type = cv_unqualified (type_decays_to (type)); |
| if (enum_p && UNSCOPED_ENUM_P (type)) |
| vec_safe_push (types[i], type); |
| if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type)) |
| type = type_promotes_to (type); |
| } |
| vec_safe_push (types[i], type); |
| } |
| } |
| |
| /* Run through the possible parameter types of both arguments, |
| creating candidates with those parameter types. */ |
| FOR_EACH_VEC_ELT_REVERSE (*(types[0]), ix, t) |
| { |
| unsigned jx; |
| tree u; |
| |
| if (!types[1]->is_empty ()) |
| FOR_EACH_VEC_ELT_REVERSE (*(types[1]), jx, u) |
| add_builtin_candidate |
| (candidates, code, code2, fnname, t, |
| u, args, argtypes, flags, complain); |
| else |
| add_builtin_candidate |
| (candidates, code, code2, fnname, t, |
| NULL_TREE, args, argtypes, flags, complain); |
| } |
| |
| release_tree_vector (types[0]); |
| release_tree_vector (types[1]); |
| } |
| |
| |
| /* If TMPL can be successfully instantiated as indicated by |
| EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES. |
| |
| TMPL is the template. EXPLICIT_TARGS are any explicit template |
| arguments. ARGLIST is the arguments provided at the call-site. |
| This does not change ARGLIST. The RETURN_TYPE is the desired type |
| for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are |
| as for add_function_candidate. If an OBJ is supplied, FLAGS and |
| CTYPE are ignored, and OBJ is as for add_conv_candidate. */ |
| |
| static struct z_candidate* |
| add_template_candidate_real (struct z_candidate **candidates, tree tmpl, |
| tree ctype, tree explicit_targs, tree first_arg, |
| const vec<tree, va_gc> *arglist, tree return_type, |
| tree access_path, tree conversion_path, |
| int flags, tree obj, unification_kind_t strict, |
| tsubst_flags_t complain) |
| { |
| int ntparms = DECL_NTPARMS (tmpl); |
| tree targs = make_tree_vec (ntparms); |
| unsigned int len = vec_safe_length (arglist); |
| unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len; |
| unsigned int skip_without_in_chrg = 0; |
| tree first_arg_without_in_chrg = first_arg; |
| tree *args_without_in_chrg; |
| unsigned int nargs_without_in_chrg; |
| unsigned int ia, ix; |
| tree arg; |
| struct z_candidate *cand; |
| tree fn; |
| struct rejection_reason *reason = NULL; |
| int errs; |
| conversion **convs = NULL; |
| |
| /* We don't do deduction on the in-charge parameter, the VTT |
| parameter or 'this'. */ |
| if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl)) |
| { |
| if (first_arg_without_in_chrg != NULL_TREE) |
| first_arg_without_in_chrg = NULL_TREE; |
| else if (return_type && strict == DEDUCE_CALL) |
| /* We're deducing for a call to the result of a template conversion |
| function, so the args don't contain 'this'; leave them alone. */; |
| else |
| ++skip_without_in_chrg; |
| } |
| |
| if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl) |
| || DECL_BASE_CONSTRUCTOR_P (tmpl)) |
| && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl))) |
| { |
| if (first_arg_without_in_chrg != NULL_TREE) |
| first_arg_without_in_chrg = NULL_TREE; |
| else |
| ++skip_without_in_chrg; |
| } |
| |
| if (len < skip_without_in_chrg) |
| return NULL; |
| |
| if (DECL_CONSTRUCTOR_P (tmpl) && nargs == 2 |
| && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg), |
| TREE_TYPE ((*arglist)[0]))) |
| { |
| /* 12.8/6 says, "A declaration of a constructor for a class X is |
| ill-formed if its first parameter is of type (optionally cv-qualified) |
| X and either there are no other parameters or else all other |
| parameters have default arguments. A member function template is never |
| instantiated to produce such a constructor signature." |
| |
| So if we're trying to copy an object of the containing class, don't |
| consider a template constructor that has a first parameter type that |
| is just a template parameter, as we would deduce a signature that we |
| would then reject in the code below. */ |
| if (tree firstparm = FUNCTION_FIRST_USER_PARMTYPE (tmpl)) |
| { |
| firstparm = TREE_VALUE (firstparm); |
| if (PACK_EXPANSION_P (firstparm)) |
| firstparm = PACK_EXPANSION_PATTERN (firstparm); |
| if (TREE_CODE (firstparm) == TEMPLATE_TYPE_PARM) |
| { |
| gcc_assert (!explicit_targs); |
| reason = invalid_copy_with_fn_template_rejection (); |
| goto fail; |
| } |
| } |
| } |
| |
| nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0) |
| + (len - skip_without_in_chrg)); |
| args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg); |
| ia = 0; |
| if (first_arg_without_in_chrg != NULL_TREE) |
| { |
| args_without_in_chrg[ia] = first_arg_without_in_chrg; |
| ++ia; |
| } |
| for (ix = skip_without_in_chrg; |
| vec_safe_iterate (arglist, ix, &arg); |
| ++ix) |
| { |
| args_without_in_chrg[ia] = arg; |
| ++ia; |
| } |
| gcc_assert (ia == nargs_without_in_chrg); |
| |
| errs = errorcount+sorrycount; |
| if (!obj) |
| convs = alloc_conversions (nargs); |
| fn = fn_type_unification (tmpl, explicit_targs, targs, |
| args_without_in_chrg, |
| nargs_without_in_chrg, |
| return_type, strict, flags, convs, |
| false, complain & tf_decltype); |
| |
| if (fn == error_mark_node) |
| { |
| /* Don't repeat unification later if it already resulted in errors. */ |
| if (errorcount+sorrycount == errs) |
| reason = template_unification_rejection (tmpl, explicit_targs, |
| targs, args_without_in_chrg, |
| nargs_without_in_chrg, |
| return_type, strict, flags); |
| else |
| reason = template_unification_error_rejection (); |
| goto fail; |
| } |
| |
| /* Now the explicit specifier might have been deduced; check if this |
| declaration is explicit. If it is and we're ignoring non-converting |
| constructors, don't add this function to the set of candidates. */ |
| if ((flags & LOOKUP_ONLYCONVERTING) && DECL_NONCONVERTING_P (fn)) |
| return NULL; |
| |
| if (DECL_CONSTRUCTOR_P (fn) && nargs == 2) |
| { |
| tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn); |
| if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)), |
| ctype)) |
| { |
| /* We're trying to produce a constructor with a prohibited signature, |
| as discussed above; handle here any cases we didn't catch then, |
| such as X(X<T>). */ |
| reason = invalid_copy_with_fn_template_rejection (); |
| goto fail; |
| } |
| } |
| |
| if (obj != NULL_TREE) |
| /* Aha, this is a conversion function. */ |
| cand = add_conv_candidate (candidates, fn, obj, arglist, |
| access_path, conversion_path, complain); |
| else |
| cand = add_function_candidate (candidates, fn, ctype, |
| first_arg, arglist, access_path, |
| conversion_path, flags, convs, complain); |
| if (DECL_TI_TEMPLATE (fn) != tmpl) |
| /* This situation can occur if a member template of a template |
| class is specialized. Then, instantiate_template might return |
| an instantiation of the specialization, in which case the |
| DECL_TI_TEMPLATE field will point at the original |
| specialization. For example: |
| |
| template <class T> struct S { template <class U> void f(U); |
| template <> void f(int) {}; }; |
| S<double> sd; |
| sd.f(3); |
| |
| Here, TMPL will be template <class U> S<double>::f(U). |
| And, instantiate template will give us the specialization |
| template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field |
| for this will point at template <class T> template <> S<T>::f(int), |
| so that we can find the definition. For the purposes of |
| overload resolution, however, we want the original TMPL. */ |
| cand->template_decl = build_template_info (tmpl, targs); |
| else |
| cand->template_decl = DECL_TEMPLATE_INFO (fn); |
| cand->explicit_targs = explicit_targs; |
| |
| return cand; |
| fail: |
| return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL, |
| access_path, conversion_path, 0, reason, flags); |
| } |
| |
| |
| static struct z_candidate * |
| add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype, |
| tree explicit_targs, tree first_arg, |
| const vec<tree, va_gc> *arglist, tree return_type, |
| tree access_path, tree conversion_path, int flags, |
| unification_kind_t strict, tsubst_flags_t complain) |
| { |
| return |
| add_template_candidate_real (candidates, tmpl, ctype, |
| explicit_targs, first_arg, arglist, |
| return_type, access_path, conversion_path, |
| flags, NULL_TREE, strict, complain); |
| } |
| |
| /* Create an overload candidate for the conversion function template TMPL, |
| returning RETURN_TYPE, which will be invoked for expression OBJ to produce a |
| pointer-to-function which will in turn be called with the argument list |
| ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is |
| passed on to implicit_conversion. */ |
| |
| static struct z_candidate * |
| add_template_conv_candidate (struct z_candidate **candidates, tree tmpl, |
| tree obj, |
| const vec<tree, va_gc> *arglist, |
| tree return_type, tree access_path, |
| tree conversion_path, tsubst_flags_t complain) |
| { |
| /* Making this work broke PR 71117 and 85118, so until the committee resolves |
| core issue 2189, let's disable this candidate if there are any call |
| operators. */ |
| if (*candidates) |
| return NULL; |
| |
| return |
| add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE, |
| NULL_TREE, arglist, return_type, access_path, |
| conversion_path, 0, obj, DEDUCE_CALL, |
| complain); |
| } |
| |
| /* The CANDS are the set of candidates that were considered for |
| overload resolution. Return the set of viable candidates, or CANDS |
| if none are viable. If any of the candidates were viable, set |
| *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be |
| considered viable only if it is strictly viable. */ |
| |
| static struct z_candidate* |
| splice_viable (struct z_candidate *cands, |
| bool strict_p, |
| bool *any_viable_p) |
| { |
| struct z_candidate *viable; |
| struct z_candidate **last_viable; |
| struct z_candidate **cand; |
| bool found_strictly_viable = false; |
| |
| /* Be strict inside templates, since build_over_call won't actually |
| do the conversions to get pedwarns. */ |
| if (processing_template_decl) |
| strict_p = true; |
| |
| viable = NULL; |
| last_viable = &viable; |
| *any_viable_p = false; |
| |
| cand = &cands; |
| while (*cand) |
| { |
| struct z_candidate *c = *cand; |
| if (!strict_p |
| && (c->viable == 1 || TREE_CODE (c->fn) == TEMPLATE_DECL)) |
| { |
| /* Be strict in the presence of a viable candidate. Also if |
| there are template candidates, so that we get deduction errors |
| for them instead of silently preferring a bad conversion. */ |
| strict_p = true; |
| if (viable && !found_strictly_viable) |
| { |
| /* Put any spliced near matches back onto the main list so |
| that we see them if there is no strict match. */ |
| *any_viable_p = false; |
| *last_viable = cands; |
| cands = viable; |
| viable = NULL; |
| last_viable = &viable; |
| } |
| } |
| |
| if (strict_p ? c->viable == 1 : c->viable) |
| { |
| *last_viable = c; |
| *cand = c->next; |
| c->next = NULL; |
| last_viable = &c->next; |
| *any_viable_p = true; |
| if (c->viable == 1) |
| found_strictly_viable = true; |
| } |
| else |
| cand = &c->next; |
| } |
| |
| return viable ? viable : cands; |
| } |
| |
| static bool |
| any_strictly_viable (struct z_candidate *cands) |
| { |
| for (; cands; cands = cands->next) |
| if (cands->viable == 1) |
| return true; |
| return false; |
| } |
| |
| /* OBJ is being used in an expression like "OBJ.f (...)". In other |
| words, it is about to become the "this" pointer for a member |
| function call. Take the address of the object. */ |
| |
| static tree |
| build_this (tree obj) |
| { |
| /* In a template, we are only concerned about the type of the |
| expression, so we can take a shortcut. */ |
| if (processing_template_decl) |
| return build_address (obj); |
| |
| return cp_build_addr_expr (obj, tf_warning_or_error); |
| } |
| |
| /* Returns true iff functions are equivalent. Equivalent functions are |
| not '==' only if one is a function-local extern function or if |
| both are extern "C". */ |
| |
| static inline int |
| equal_functions (tree fn1, tree fn2) |
| { |
| if (TREE_CODE (fn1) != TREE_CODE (fn2)) |
| return 0; |
| if (TREE_CODE (fn1) == TEMPLATE_DECL) |
| return fn1 == fn2; |
| if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2) |
| || DECL_EXTERN_C_FUNCTION_P (fn1)) |
| return decls_match (fn1, fn2); |
| return fn1 == fn2; |
| } |
| |
| /* Print information about a candidate FN being rejected due to INFO. */ |
| |
| static void |
| print_conversion_rejection (location_t loc, struct conversion_info *info, |
| tree fn) |
| { |
| tree from = info->from; |
| if (!TYPE_P (from)) |
| from = lvalue_type (from); |
| if (info->n_arg == -1) |
| { |
| /* Conversion of implicit `this' argument failed. */ |
| if (!TYPE_P (info->from)) |
| /* A bad conversion for 'this' must be discarding cv-quals. */ |
| inform (loc, " passing %qT as %<this%> " |
| "argument discards qualifiers", |
| from); |
| else |
| inform (loc, " no known conversion for implicit " |
| "%<this%> parameter from %qH to %qI", |
| from, info->to_type); |
| } |
| else if (!TYPE_P (info->from)) |
| { |
| if (info->n_arg >= 0) |
| inform (loc, " conversion of argument %d would be ill-formed:", |
| info->n_arg + 1); |
| perform_implicit_conversion (info->to_type, info->from, |
| tf_warning_or_error); |
| } |
| else if (info->n_arg == -2) |
| /* Conversion of conversion function return value failed. */ |
| inform (loc, " no known conversion from %qH to %qI", |
| from, info->to_type); |
| else |
| { |
| if (TREE_CODE (fn) == FUNCTION_DECL) |
| loc = get_fndecl_argument_location (fn, info->n_arg); |
| inform (loc, " no known conversion for argument %d from %qH to %qI", |
| info->n_arg + 1, from, info->to_type); |
| } |
| } |
| |
| /* Print information about a candidate with WANT parameters and we found |
| HAVE. */ |
| |
| static void |
| print_arity_information (location_t loc, unsigned int have, unsigned int want) |
| { |
| inform_n (loc, want, |
| " candidate expects %d argument, %d provided", |
| " candidate expects %d arguments, %d provided", |
| want, have); |
| } |
| |
| /* Print information about one overload candidate CANDIDATE. MSGSTR |
| is the text to print before the candidate itself. |
| |
| NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected |
| to have been run through gettext by the caller. This wart makes |
| life simpler in print_z_candidates and for the translators. */ |
| |
| static void |
| print_z_candidate (location_t loc, const char *msgstr, |
| struct z_candidate *candidate) |
| { |
| const char *msg = (msgstr == NULL |
| ? "" |
| : ACONCAT ((_(msgstr), " ", NULL))); |
| tree fn = candidate->fn; |
| if (flag_new_inheriting_ctors) |
| fn = strip_inheriting_ctors (fn); |
| location_t cloc = location_of (fn); |
| |
| if (identifier_p (fn)) |
| { |
| cloc = loc; |
| if (candidate->num_convs == 3) |
| inform (cloc, "%s%<%D(%T, %T, %T)%> (built-in)", msg, fn, |
| candidate->convs[0]->type, |
| candidate->convs[1]->type, |
| candidate->convs[2]->type); |
| else if (candidate->num_convs == 2) |
| inform (cloc, "%s%<%D(%T, %T)%> (built-in)", msg, fn, |
| candidate->convs[0]->type, |
| candidate->convs[1]->type); |
| else |
| inform (cloc, "%s%<%D(%T)%> (built-in)", msg, fn, |
| candidate->convs[0]->type); |
| } |
| else if (TYPE_P (fn)) |
| inform (cloc, "%s%qT (conversion)", msg, fn); |
| else if (candidate->viable == -1) |
| inform (cloc, "%s%#qD (near match)", msg, fn); |
| else if (DECL_DELETED_FN (fn)) |
| inform (cloc, "%s%#qD (deleted)", msg, fn); |
| else if (candidate->reversed ()) |
| inform (cloc, "%s%#qD (reversed)", msg, fn); |
| else if (candidate->rewritten ()) |
| inform (cloc, "%s%#qD (rewritten)", msg, fn); |
| else |
| inform (cloc, "%s%#qD", msg, fn); |
| if (fn != candidate->fn) |
| { |
| cloc = location_of (candidate->fn); |
| inform (cloc, " inherited here"); |
| } |
| /* Give the user some information about why this candidate failed. */ |
| if (candidate->reason != NULL) |
| { |
| struct rejection_reason *r = candidate->reason; |
| |
| switch (r->code) |
| { |
| case rr_arity: |
| print_arity_information (cloc, r->u.arity.actual, |
| r->u.arity.expected); |
| break; |
| case rr_arg_conversion: |
| print_conversion_rejection (cloc, &r->u.conversion, fn); |
| break; |
| case rr_bad_arg_conversion: |
| print_conversion_rejection (cloc, &r->u.bad_conversion, fn); |
| break; |
| case rr_explicit_conversion: |
| inform (cloc, " return type %qT of explicit conversion function " |
| "cannot be converted to %qT with a qualification " |
| "conversion", r->u.conversion.from, |
| r->u.conversion.to_type); |
| break; |
| case rr_template_conversion: |
| inform (cloc, " conversion from return type %qT of template " |
| "conversion function specialization to %qT is not an " |
| "exact match", r->u.conversion.from, |
| r->u.conversion.to_type); |
| break; |
| case rr_template_unification: |
| /* We use template_unification_error_rejection if unification caused |
| actual non-SFINAE errors, in which case we don't need to repeat |
| them here. */ |
| if (r->u.template_unification.tmpl == NULL_TREE) |
| { |
| inform (cloc, " substitution of deduced template arguments " |
| "resulted in errors seen above"); |
| break; |
| } |
| /* Re-run template unification with diagnostics. */ |
| inform (cloc, " template argument deduction/substitution failed:"); |
| fn_type_unification (r->u.template_unification.tmpl, |
| r->u.template_unification.explicit_targs, |
| (make_tree_vec |
| (r->u.template_unification.num_targs)), |
| r->u.template_unification.args, |
| r->u.template_unification.nargs, |
| r->u.template_unification.return_type, |
| r->u.template_unification.strict, |
| r->u.template_unification.flags, |
| NULL, true, false); |
| break; |
| case rr_invalid_copy: |
| inform (cloc, |
| " a constructor taking a single argument of its own " |
| "class type is invalid"); |
| break; |
| case rr_constraint_failure: |
| diagnose_constraints (cloc, fn, NULL_TREE); |
| break; |
| case rr_inherited_ctor: |
| inform (cloc, " an inherited constructor is not a candidate for " |
| "initialization from an expression of the same or derived " |
| "type"); |
| break; |
| case rr_none: |
| default: |
| /* This candidate didn't have any issues or we failed to |
| handle a particular code. Either way... */ |
| gcc_unreachable (); |
| } |
| } |
| } |
| |
| static void |
| print_z_candidates (location_t loc, struct z_candidate *candidates) |
| { |
| struct z_candidate *cand1; |
| struct z_candidate **cand2; |
| |
| if (!candidates) |
| return; |
| |
| /* Remove non-viable deleted candidates. */ |
| cand1 = candidates; |
| for (cand2 = &cand1; *cand2; ) |
| { |
| if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL |
| && !(*cand2)->viable |
| && DECL_DELETED_FN ((*cand2)->fn)) |
| *cand2 = (*cand2)->next; |
| else |
| cand2 = &(*cand2)->next; |
| } |
| /* ...if there are any non-deleted ones. */ |
| if (cand1) |
| candidates = cand1; |
| |
| /* There may be duplicates in the set of candidates. We put off |
| checking this condition as long as possible, since we have no way |
| to eliminate duplicates from a set of functions in less than n^2 |
| time. Now we are about to emit an error message, so it is more |
| permissible to go slowly. */ |
| for (cand1 = candidates; cand1; cand1 = cand1->next) |
| { |
| tree fn = cand1->fn; |
| /* Skip builtin candidates and conversion functions. */ |
| if (!DECL_P (fn)) |
| continue; |
| cand2 = &cand1->next; |
| while (*cand2) |
| { |
| if (DECL_P ((*cand2)->fn) |
| && equal_functions (fn, (*cand2)->fn)) |
| *cand2 = (*cand2)->next; |
| else |
| cand2 = &(*cand2)->next; |
| } |
| } |
| |
| for (; candidates; candidates = candidates->next) |
| print_z_candidate (loc, N_("candidate:"), candidates); |
| } |
| |
| /* USER_SEQ is a user-defined conversion sequence, beginning with a |
| USER_CONV. STD_SEQ is the standard conversion sequence applied to |
| the result of the conversion function to convert it to the final |
| desired type. Merge the two sequences into a single sequence, |
| and return the merged sequence. */ |
| |
| static conversion * |
| merge_conversion_sequences (conversion *user_seq, conversion *std_seq) |
| { |
| conversion **t; |
| bool bad = user_seq->bad_p; |
| |
| gcc_assert (user_seq->kind == ck_user); |
| |
| /* Find the end of the second conversion sequence. */ |
| for (t = &std_seq; (*t)->kind != ck_identity; t = &((*t)->u.next)) |
| { |
| /* The entire sequence is a user-conversion sequence. */ |
| (*t)->user_conv_p = true; |
| if (bad) |
| (*t)->bad_p = true; |
| } |
| |
| if ((*t)->rvaluedness_matches_p) |
| /* We're binding a reference directly to the result of the conversion. |
| build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return |
| type, but we want it back. */ |
| user_seq->type = TREE_TYPE (TREE_TYPE (user_seq->cand->fn)); |
| |
| /* Replace the identity conversion with the user conversion |
| sequence. */ |
| *t = user_seq; |
| |
| return std_seq; |
| } |
| |
| /* Handle overload resolution for initializing an object of class type from |
| an initializer list. First we look for a suitable constructor that |
| takes a std::initializer_list; if we don't find one, we then look for a |
| non-list constructor. |
| |
| Parameters are as for add_candidates, except that the arguments are in |
| the form of a CONSTRUCTOR (the initializer list) rather than a vector, and |
| the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */ |
| |
| static void |
| add_list_candidates (tree fns, tree first_arg, |
| const vec<tree, va_gc> *args, tree totype, |
| tree explicit_targs, bool template_only, |
| tree conversion_path, tree access_path, |
| int flags, |
| struct z_candidate **candidates, |
| tsubst_flags_t complain) |
| { |
| gcc_assert (*candidates == NULL); |
| |
| /* We're looking for a ctor for list-initialization. */ |
| flags |= LOOKUP_LIST_INIT_CTOR; |
| /* And we don't allow narrowing conversions. We also use this flag to |
| avoid the copy constructor call for copy-list-initialization. */ |
| flags |= LOOKUP_NO_NARROWING; |
| |
| unsigned nart = num_artificial_parms_for (OVL_FIRST (fns)) - 1; |
| tree init_list = (*args)[nart]; |
| |
| /* Always use the default constructor if the list is empty (DR 990). */ |
| if (CONSTRUCTOR_NELTS (init_list) == 0 |
| && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype)) |
| ; |
| /* If the class has a list ctor, try passing the list as a single |
| argument first, but only consider list ctors. */ |
| else if (TYPE_HAS_LIST_CTOR (totype)) |
| { |
| flags |= LOOKUP_LIST_ONLY; |
| add_candidates (fns, first_arg, args, NULL_TREE, |
| explicit_targs, template_only, conversion_path, |
| access_path, flags, candidates, complain); |
| if (any_strictly_viable (*candidates)) |
| return; |
| } |
| |
| /* Expand the CONSTRUCTOR into a new argument vec. */ |
| vec<tree, va_gc> *new_args; |
| vec_alloc (new_args, nart + CONSTRUCTOR_NELTS (init_list)); |
| for (unsigned i = 0; i < nart; ++i) |
| new_args->quick_push ((*args)[i]); |
| for (unsigned i = 0; i < CONSTRUCTOR_NELTS (init_list); ++i) |
| new_args->quick_push (CONSTRUCTOR_ELT (init_list, i)->value); |
| |
| /* We aren't looking for list-ctors anymore. */ |
| flags &= ~LOOKUP_LIST_ONLY; |
| /* We allow more user-defined conversions within an init-list. */ |
| flags &= ~LOOKUP_NO_CONVERSION; |
| |
| add_candidates (fns, first_arg, new_args, NULL_TREE, |
| explicit_targs, template_only, conversion_path, |
| access_path, flags, candidates, complain); |
| } |
| |
| /* Returns the best overload candidate to perform the requested |
| conversion. This function is used for three the overloading situations |
| described in [over.match.copy], [over.match.conv], and [over.match.ref]. |
| If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as |
| per [dcl.init.ref], so we ignore temporary bindings. */ |
| |
| static struct z_candidate * |
| build_user_type_conversion_1 (tree totype, tree expr, int flags, |
| tsubst_flags_t complain) |
| { |
| struct z_candidate *candidates, *cand; |
| tree fromtype; |
| tree ctors = NULL_TREE; |
| tree conv_fns = NULL_TREE; |
| conversion *conv = NULL; |
| tree first_arg = NULL_TREE; |
| vec<tree, va_gc> *args = NULL; |
| bool any_viable_p; |
| int convflags; |
| |
| if (!expr) |
| return NULL; |
| |
| fromtype = TREE_TYPE (expr); |
| |
| /* We represent conversion within a hierarchy using RVALUE_CONV and |
| BASE_CONV, as specified by [over.best.ics]; these become plain |
| constructor calls, as specified in [dcl.init]. */ |
| gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype) |
| || !DERIVED_FROM_P (totype, fromtype)); |
| |
| if (CLASS_TYPE_P (totype)) |
| /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid |
| creating a garbage BASELINK; constructors can't be inherited. */ |
| ctors = get_class_binding (totype, complete_ctor_identifier); |
| |
| if (MAYBE_CLASS_TYPE_P (fromtype)) |
| { |
| tree to_nonref = non_reference (totype); |
| if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) || |
| (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype) |
| && DERIVED_FROM_P (to_nonref, fromtype))) |
| { |
| /* [class.conv.fct] A conversion function is never used to |
| convert a (possibly cv-qualified) object to the (possibly |
| cv-qualified) same object type (or a reference to it), to a |
| (possibly cv-qualified) base class of that type (or a |
| reference to it)... */ |
| } |
| else |
| conv_fns = lookup_conversions (fromtype); |
| } |
| |
| candidates = 0; |
| flags |= LOOKUP_NO_CONVERSION; |
| if (BRACE_ENCLOSED_INITIALIZER_P (expr)) |
| flags |= LOOKUP_NO_NARROWING; |
| |
| /* It's OK to bind a temporary for converting constructor arguments, but |
| not in converting the return value of a conversion operator. */ |
| convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION |
| | (flags & LOOKUP_NO_NARROWING)); |
| flags &= ~LOOKUP_NO_TEMP_BIND; |
| |
| if (ctors) |
| { |
| int ctorflags = flags; |
| |
| first_arg = build_dummy_object (totype); |
| |
| /* We should never try to call the abstract or base constructor |
| from here. */ |
| gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors)) |
| && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors))); |
| |
| args = make_tree_vector_single (expr); |
| if (BRACE_ENCLOSED_INITIALIZER_P (expr)) |
| { |
| /* List-initialization. */ |
| add_list_candidates (ctors, first_arg, args, totype, NULL_TREE, |
| false, TYPE_BINFO (totype), TYPE_BINFO (totype), |
| ctorflags, &candidates, complain); |
| } |
| else |
| { |
| add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false, |
| TYPE_BINFO (totype), TYPE_BINFO (totype), |
| ctorflags, &candidates, complain); |
| } |
| |
| for (cand = candidates; cand; cand = cand->next) |
| { |
| cand->second_conv = build_identity_conv (totype, NULL_TREE); |
| |
| /* If totype isn't a reference, and LOOKUP_ONLYCONVERTING is |
| set, then this is copy-initialization. In that case, "The |
| result of the call is then used to direct-initialize the |
| object that is the destination of the copy-initialization." |
| [dcl.init] |
| |
| We represent this in the conversion sequence with an |
| rvalue conversion, which means a constructor call. */ |
| if (!TYPE_REF_P (totype) |
| && cxx_dialect < cxx17 |
| && (flags & LOOKUP_ONLYCONVERTING) |
| && !(convflags & LOOKUP_NO_TEMP_BIND)) |
| cand->second_conv |
| = build_conv (ck_rvalue, totype, cand->second_conv); |
| } |
| } |
| |
| if (conv_fns) |
| { |
| if (BRACE_ENCLOSED_INITIALIZER_P (expr)) |
| first_arg = CONSTRUCTOR_ELT (expr, 0)->value; |
| else |
| first_arg = expr; |
| } |
| |
| for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns)) |
| { |
| tree conversion_path = TREE_PURPOSE (conv_fns); |
| struct z_candidate *old_candidates; |
| |
| /* If we are called to convert to a reference type, we are trying to |
| find a direct binding, so don't even consider temporaries. If |
| we don't find a direct binding, the caller will try again to |
| look for a temporary binding. */ |
| if (TYPE_REF_P (totype)) |
| convflags |= LOOKUP_NO_TEMP_BIND; |
| |
| old_candidates = candidates; |
| add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype, |
| NULL_TREE, false, |
| conversion_path, TYPE_BINFO (fromtype), |
| flags, &candidates, complain); |
| |
| for (cand = candidates; cand != old_candidates; cand = cand->next) |
| { |
| if (cand->viable == 0) |
| /* Already rejected, don't change to -1. */ |
| continue; |
| |
| tree rettype = TREE_TYPE (TREE_TYPE (cand->fn)); |
| conversion *ics |
| = implicit_conversion (totype, |
| rettype, |
| 0, |
| /*c_cast_p=*/false, convflags, |
| complain); |
| |
| /* If LOOKUP_NO_TEMP_BIND isn't set, then this is |
| copy-initialization. In that case, "The result of the |
| call is then used to direct-initialize the object that is |
| the destination of the copy-initialization." [dcl.init] |
| |
| We represent this in the conversion sequence with an |
| rvalue conversion, which means a constructor call. But |
| don't add a second rvalue conversion if there's already |
| one there. Which there really shouldn't be, but it's |
| harmless since we'd add it here anyway. */ |
| if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue |
| && !(convflags & LOOKUP_NO_TEMP_BIND)) |
| ics = build_conv (ck_rvalue, totype, ics); |
| |
| cand->second_conv = ics; |
| |
| if (!ics) |
| { |
| cand->viable = 0; |
| cand->reason = arg_conversion_rejection (NULL_TREE, -2, |
| rettype, totype, |
| EXPR_LOCATION (expr)); |
| } |
| else if (TYPE_REF_P (totype) && !ics->rvaluedness_matches_p |
| /* Limit this to non-templates for now (PR90546). */ |
| && !cand->template_decl |
| && TREE_CODE (TREE_TYPE (totype)) != FUNCTION_TYPE) |
| { |
| /* If we are called to convert to a reference type, we are trying |
| to find a direct binding per [over.match.ref], so rvaluedness |
| must match for non-functions. */ |
| cand->viable = 0; |
| } |
| else if (DECL_NONCONVERTING_P (cand->fn) |
| && ics->rank > cr_exact) |
| { |
| /* 13.3.1.5: For direct-initialization, those explicit |
| conversion functions that are not hidden within S and |
| yield type T or a type that can be converted to type T |
| with a qualification conversion (4.4) are also candidate |
| functions. */ |
| /* 13.3.1.6 doesn't have a parallel restriction, but it should; |
| I've raised this issue with the committee. --jason 9/2011 */ |
| cand->viable = -1; |
| cand->reason = explicit_conversion_rejection (rettype, totype); |
| } |
| else if (cand->viable == 1 && ics->bad_p) |
| { |
| cand->viable = -1; |
| cand->reason |
| = bad_arg_conversion_rejection (NULL_TREE, -2, |
| rettype, totype, |
| EXPR_LOCATION (expr)); |
| } |
| else if (primary_template_specialization_p (cand->fn) |
| && ics->rank > cr_exact) |
| { |
| /* 13.3.3.1.2: If the user-defined conversion is specified by |
| a specialization of a conversion function template, the |
| second standard conversion sequence shall have exact match |
| rank. */ |
| cand->viable = -1; |
| cand->reason = template_conversion_rejection (rettype, totype); |
| } |
| } |
| } |
| |
| candidates = splice_viable (candidates, false, &any_viable_p); |
| if (!any_viable_p) |
| { |
| if (args) |
| release_tree_vector (args); |
| return NULL; |
| } |
| |
| cand = tourney (candidates, complain); |
| if (cand == NULL) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| error_at (cp_expr_loc_or_input_loc (expr), |
| "conversion from %qH to %qI is ambiguous", |
| fromtype, totype); |
| print_z_candidates (location_of (expr), candidates); |
| } |
| |
| cand = candidates; /* any one will do */ |
| cand->second_conv = build_ambiguous_conv (totype, expr); |
| cand->second_conv->user_conv_p = true; |
| if (!any_strictly_viable (candidates)) |
| cand->second_conv->bad_p = true; |
| if (flags & LOOKUP_ONLYCONVERTING) |
| cand->second_conv->need_temporary_p = true; |
| /* If there are viable candidates, don't set ICS_BAD_FLAG; an |
| ambiguous conversion is no worse than another user-defined |
| conversion. */ |
| |
| return cand; |
| } |
| |
| tree convtype; |
| if (!DECL_CONSTRUCTOR_P (cand->fn)) |
| convtype = non_reference (TREE_TYPE (TREE_TYPE (cand->fn))); |
| else if (cand->second_conv->kind == ck_rvalue) |
| /* DR 5: [in the first step of copy-initialization]...if the function |
| is a constructor, the call initializes a temporary of the |
| cv-unqualified version of the destination type. */ |
| convtype = cv_unqualified (totype); |
| else |
| convtype = totype; |
| /* Build the user conversion sequence. */ |
| conv = build_conv |
| (ck_user, |
| convtype, |
| build_identity_conv (TREE_TYPE (expr), expr)); |
| conv->cand = cand; |
| if (cand->viable == -1) |
| conv->bad_p = true; |
| |
| /* We're performing the maybe-rvalue overload resolution and |
| a conversion function is in play. Reject converting the return |
| value of the conversion function to a base class. */ |
| if ((flags & LOOKUP_PREFER_RVALUE) && !DECL_CONSTRUCTOR_P (cand->fn)) |
| for (conversion *t = cand->second_conv; t; t = next_conversion (t)) |
| if (t->kind == ck_base) |
| return NULL; |
| |
| /* Remember that this was a list-initialization. */ |
| if (flags & LOOKUP_NO_NARROWING) |
| conv->check_narrowing = true; |
| |
| /* Combine it with the second conversion sequence. */ |
| cand->second_conv = merge_conversion_sequences (conv, |
| cand->second_conv); |
| |
| return cand; |
| } |
| |
| /* Wrapper for above. */ |
| |
| tree |
| build_user_type_conversion (tree totype, tree expr, int flags, |
| tsubst_flags_t complain) |
| { |
| struct z_candidate *cand; |
| tree ret; |
| |
| bool subtime = timevar_cond_start (TV_OVERLOAD); |
| cand = build_user_type_conversion_1 (totype, expr, flags, complain); |
| |
| if (cand) |
| { |
| if (cand->second_conv->kind == ck_ambig) |
| ret = error_mark_node; |
| else |
| { |
| expr = convert_like (cand->second_conv, expr, complain); |
| ret = convert_from_reference (expr); |
| } |
| } |
| else |
| ret = NULL_TREE; |
| |
| timevar_cond_stop (TV_OVERLOAD, subtime); |
| return ret; |
| } |
| |
| /* Worker for build_converted_constant_expr. */ |
| |
| static tree |
| build_converted_constant_expr_internal (tree type, tree expr, |
| int flags, tsubst_flags_t complain) |
| { |
| conversion *conv; |
| void *p; |
| tree t; |
| location_t loc = cp_expr_loc_or_input_loc (expr); |
| |
| if (error_operand_p (expr)) |
| return error_mark_node; |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| conv = implicit_conversion (type, TREE_TYPE (expr), expr, |
| /*c_cast_p=*/false, flags, complain); |
| |
| /* A converted constant expression of type T is an expression, implicitly |
| converted to type T, where the converted expression is a constant |
| expression and the implicit conversion sequence contains only |
| |
| * user-defined conversions, |
| * lvalue-to-rvalue conversions (7.1), |
| * array-to-pointer conversions (7.2), |
| * function-to-pointer conversions (7.3), |
| * qualification conversions (7.5), |
| * integral promotions (7.6), |
| * integral conversions (7.8) other than narrowing conversions (11.6.4), |
| * null pointer conversions (7.11) from std::nullptr_t, |
| * null member pointer conversions (7.12) from std::nullptr_t, and |
| * function pointer conversions (7.13), |
| |
| and where the reference binding (if any) binds directly. */ |
| |
| for (conversion *c = conv; |
| conv && c->kind != ck_identity; |
| c = next_conversion (c)) |
| { |
| switch (c->kind) |
| { |
| /* A conversion function is OK. If it isn't constexpr, we'll |
| complain later that the argument isn't constant. */ |
| case ck_user: |
| /* The lvalue-to-rvalue conversion is OK. */ |
| case ck_rvalue: |
| /* Array-to-pointer and function-to-pointer. */ |
| case ck_lvalue: |
| /* Function pointer conversions. */ |
| case ck_fnptr: |
| /* Qualification conversions. */ |
| case ck_qual: |
| break; |
| |
| case ck_ref_bind: |
| if (c->need_temporary_p) |
| { |
| if (complain & tf_error) |
| error_at (loc, "initializing %qH with %qI in converted " |
| "constant expression does not bind directly", |
| type, next_conversion (c)->type); |
| conv = NULL; |
| } |
| break; |
| |
| case ck_base: |
| case ck_pmem: |
| case ck_ptr: |
| case ck_std: |
| t = next_conversion (c)->type; |
| if (INTEGRAL_OR_ENUMERATION_TYPE_P (t) |
| && INTEGRAL_OR_ENUMERATION_TYPE_P (type)) |
| /* Integral promotion or conversion. */ |
| break; |
| if (NULLPTR_TYPE_P (t)) |
| /* Conversion from nullptr to pointer or pointer-to-member. */ |
| break; |
| |
| if (complain & tf_error) |
| error_at (loc, "conversion from %qH to %qI in a " |
| "converted constant expression", t, type); |
| /* fall through. */ |
| |
| default: |
| conv = NULL; |
| break; |
| } |
| } |
| |
| /* Avoid confusing convert_nontype_argument by introducing |
| a redundant conversion to the same reference type. */ |
| if (conv && conv->kind == ck_ref_bind |
| && REFERENCE_REF_P (expr)) |
| { |
| tree ref = TREE_OPERAND (expr, 0); |
| if (same_type_p (type, TREE_TYPE (ref))) |
| return ref; |
| } |
| |
| if (conv) |
| { |
| /* Don't copy a class in a template. */ |
| if (CLASS_TYPE_P (type) && conv->kind == ck_rvalue |
| && processing_template_decl) |
| conv = next_conversion (conv); |
| |
| /* Issuing conversion warnings for value-dependent expressions is |
| likely too noisy. */ |
| warning_sentinel w (warn_conversion); |
| conv->check_narrowing = true; |
| conv->check_narrowing_const_only = true; |
| expr = convert_like (conv, expr, complain); |
| } |
| else |
| { |
| if (complain & tf_error) |
| error_at (loc, "could not convert %qE from %qH to %qI", expr, |
| TREE_TYPE (expr), type); |
| expr = error_mark_node; |
| } |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return expr; |
| } |
| |
| /* Subroutine of convert_nontype_argument. |
| |
| EXPR is an expression used in a context that requires a converted |
| constant-expression, such as a template non-type parameter. Do any |
| necessary conversions (that are permitted for converted |
| constant-expressions) to convert it to the desired type. |
| |
| This function doesn't consider explicit conversion functions. If |
| you mean to use "a contextually converted constant expression of type |
| bool", use build_converted_constant_bool_expr. |
| |
| If conversion is successful, returns the converted expression; |
| otherwise, returns error_mark_node. */ |
| |
| tree |
| build_converted_constant_expr (tree type, tree expr, tsubst_flags_t complain) |
| { |
| return build_converted_constant_expr_internal (type, expr, LOOKUP_IMPLICIT, |
| complain); |
| } |
| |
| /* Used to create "a contextually converted constant expression of type |
| bool". This differs from build_converted_constant_expr in that it |
| also considers explicit conversion functions. */ |
| |
| tree |
| build_converted_constant_bool_expr (tree expr, tsubst_flags_t complain) |
| { |
| return build_converted_constant_expr_internal (boolean_type_node, expr, |
| LOOKUP_NORMAL, complain); |
| } |
| |
| /* Do any initial processing on the arguments to a function call. */ |
| |
| vec<tree, va_gc> * |
| resolve_args (vec<tree, va_gc> *args, tsubst_flags_t complain) |
| { |
| unsigned int ix; |
| tree arg; |
| |
| FOR_EACH_VEC_SAFE_ELT (args, ix, arg) |
| { |
| if (error_operand_p (arg)) |
| return NULL; |
| else if (VOID_TYPE_P (TREE_TYPE (arg))) |
| { |
| if (complain & tf_error) |
| error_at (cp_expr_loc_or_input_loc (arg), |
| "invalid use of void expression"); |
| return NULL; |
| } |
| else if (invalid_nonstatic_memfn_p (EXPR_LOCATION (arg), arg, complain)) |
| return NULL; |
| } |
| return args; |
| } |
| |
| /* Perform overload resolution on FN, which is called with the ARGS. |
| |
| Return the candidate function selected by overload resolution, or |
| NULL if the event that overload resolution failed. In the case |
| that overload resolution fails, *CANDIDATES will be the set of |
| candidates considered, and ANY_VIABLE_P will be set to true or |
| false to indicate whether or not any of the candidates were |
| viable. |
| |
| The ARGS should already have gone through RESOLVE_ARGS before this |
| function is called. */ |
| |
| static struct z_candidate * |
| perform_overload_resolution (tree fn, |
| const vec<tree, va_gc> *args, |
| struct z_candidate **candidates, |
| bool *any_viable_p, tsubst_flags_t complain) |
| { |
| struct z_candidate *cand; |
| tree explicit_targs; |
| int template_only; |
| |
| bool subtime = timevar_cond_start (TV_OVERLOAD); |
| |
| explicit_targs = NULL_TREE; |
| template_only = 0; |
| |
| *candidates = NULL; |
| *any_viable_p = true; |
| |
| /* Check FN. */ |
| gcc_assert (OVL_P (fn) || TREE_CODE (fn) == TEMPLATE_ID_EXPR); |
| |
| if (TREE_CODE (fn) == TEMPLATE_ID_EXPR) |
| { |
| explicit_targs = TREE_OPERAND (fn, 1); |
| fn = TREE_OPERAND (fn, 0); |
| template_only = 1; |
| } |
| |
| /* Add the various candidate functions. */ |
| add_candidates (fn, NULL_TREE, args, NULL_TREE, |
| explicit_targs, template_only, |
| /*conversion_path=*/NULL_TREE, |
| /*access_path=*/NULL_TREE, |
| LOOKUP_NORMAL, |
| candidates, complain); |
| |
| *candidates = splice_viable (*candidates, false, any_viable_p); |
| if (*any_viable_p) |
| cand = tourney (*candidates, complain); |
| else |
| cand = NULL; |
| |
| timevar_cond_stop (TV_OVERLOAD, subtime); |
| return cand; |
| } |
| |
| /* Print an error message about being unable to build a call to FN with |
| ARGS. ANY_VIABLE_P indicates whether any candidate functions could |
| be located; CANDIDATES is a possibly empty list of such |
| functions. */ |
| |
| static void |
| print_error_for_call_failure (tree fn, vec<tree, va_gc> *args, |
| struct z_candidate *candidates) |
| { |
| tree targs = NULL_TREE; |
| if (TREE_CODE (fn) == TEMPLATE_ID_EXPR) |
| { |
| targs = TREE_OPERAND (fn, 1); |
| fn = TREE_OPERAND (fn, 0); |
| } |
| tree name = OVL_NAME (fn); |
| location_t loc = location_of (name); |
| if (targs) |
| name = lookup_template_function (name, targs); |
| |
| auto_diagnostic_group d; |
| if (!any_strictly_viable (candidates)) |
| error_at (loc, "no matching function for call to %<%D(%A)%>", |
| name, build_tree_list_vec (args)); |
| else |
| error_at (loc, "call of overloaded %<%D(%A)%> is ambiguous", |
| name, build_tree_list_vec (args)); |
| if (candidates) |
| print_z_candidates (loc, candidates); |
| } |
| |
| /* Return an expression for a call to FN (a namespace-scope function, |
| or a static member function) with the ARGS. This may change |
| ARGS. */ |
| |
| tree |
| build_new_function_call (tree fn, vec<tree, va_gc> **args, |
| tsubst_flags_t complain) |
| { |
| struct z_candidate *candidates, *cand; |
| bool any_viable_p; |
| void *p; |
| tree result; |
| |
| if (args != NULL && *args != NULL) |
| { |
| *args = resolve_args (*args, complain); |
| if (*args == NULL) |
| return error_mark_node; |
| } |
| |
| if (flag_tm) |
| tm_malloc_replacement (fn); |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p, |
| complain); |
| |
| if (!cand) |
| { |
| if (complain & tf_error) |
| { |
| // If there is a single (non-viable) function candidate, |
| // let the error be diagnosed by cp_build_function_call_vec. |
| if (!any_viable_p && candidates && ! candidates->next |
| && (TREE_CODE (candidates->fn) == FUNCTION_DECL)) |
| return cp_build_function_call_vec (candidates->fn, args, complain); |
| |
| // Otherwise, emit notes for non-viable candidates. |
| print_error_for_call_failure (fn, *args, candidates); |
| } |
| result = error_mark_node; |
| } |
| else |
| { |
| int flags = LOOKUP_NORMAL; |
| /* If fn is template_id_expr, the call has explicit template arguments |
| (e.g. func<int>(5)), communicate this info to build_over_call |
| through flags so that later we can use it to decide whether to warn |
| about peculiar null pointer conversion. */ |
| if (TREE_CODE (fn) == TEMPLATE_ID_EXPR) |
| flags |= LOOKUP_EXPLICIT_TMPL_ARGS; |
| |
| result = build_over_call (cand, flags, complain); |
| } |
| |
| if (flag_coroutines |
| && result |
| && TREE_CODE (result) == CALL_EXPR |
| && DECL_BUILT_IN_CLASS (TREE_OPERAND (CALL_EXPR_FN (result), 0)) |
| == BUILT_IN_NORMAL) |
| result = coro_validate_builtin_call (result); |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return result; |
| } |
| |
| /* Build a call to a global operator new. FNNAME is the name of the |
| operator (either "operator new" or "operator new[]") and ARGS are |
| the arguments provided. This may change ARGS. *SIZE points to the |
| total number of bytes required by the allocation, and is updated if |
| that is changed here. *COOKIE_SIZE is non-NULL if a cookie should |
| be used. If this function determines that no cookie should be |
| used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK |
| is not NULL_TREE, it is evaluated before calculating the final |
| array size, and if it fails, the array size is replaced with |
| (size_t)-1 (usually triggering a std::bad_alloc exception). If FN |
| is non-NULL, it will be set, upon return, to the allocation |
| function called. */ |
| |
| tree |
| build_operator_new_call (tree fnname, vec<tree, va_gc> **args, |
| tree *size, tree *cookie_size, |
| tree align_arg, tree size_check, |
| tree *fn, tsubst_flags_t complain) |
| { |
| tree original_size = *size; |
| tree fns; |
| struct z_candidate *candidates; |
| struct z_candidate *cand = NULL; |
| bool any_viable_p; |
| |
| if (fn) |
| *fn = NULL_TREE; |
| /* Set to (size_t)-1 if the size check fails. */ |
| if (size_check != NULL_TREE) |
| { |
| tree errval = TYPE_MAX_VALUE (sizetype); |
| if (cxx_dialect >= cxx11 && flag_exceptions) |
| errval = throw_bad_array_new_length (); |
| *size = fold_build3 (COND_EXPR, sizetype, size_check, |
| original_size, errval); |
| } |
| vec_safe_insert (*args, 0, *size); |
| *args = resolve_args (*args, complain); |
| if (*args == NULL) |
| return error_mark_node; |
| |
| /* Based on: |
| |
| [expr.new] |
| |
| If this lookup fails to find the name, or if the allocated type |
| is not a class type, the allocation function's name is looked |
| up in the global scope. |
| |
| we disregard block-scope declarations of "operator new". */ |
| fns = lookup_name_real (fnname, 0, 1, /*block_p=*/false, 0, 0); |
| |
| if (align_arg) |
| { |
| vec<tree, va_gc>* align_args |
| = vec_copy_and_insert (*args, align_arg, 1); |
| cand = perform_overload_resolution (fns, align_args, &candidates, |
| &any_viable_p, tf_none); |
| if (cand) |
| *args = align_args; |
| /* If no aligned allocation function matches, try again without the |
| alignment. */ |
| } |
| |
| /* Figure out what function is being called. */ |
| if (!cand) |
| cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p, |
| complain); |
| |
| /* If no suitable function could be found, issue an error message |
| and give up. */ |
| if (!cand) |
| { |
| if (complain & tf_error) |
| print_error_for_call_failure (fns, *args, candidates); |
| return error_mark_node; |
| } |
| |
| /* If a cookie is required, add some extra space. Whether |
| or not a cookie is required cannot be determined until |
| after we know which function was called. */ |
| if (*cookie_size) |
| { |
| bool use_cookie = true; |
| tree arg_types; |
| |
| arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn)); |
| /* Skip the size_t parameter. */ |
| arg_types = TREE_CHAIN (arg_types); |
| /* Check the remaining parameters (if any). */ |
| if (arg_types |
| && TREE_CHAIN (arg_types) == void_list_node |
| && same_type_p (TREE_VALUE (arg_types), |
| ptr_type_node)) |
| use_cookie = false; |
| /* If we need a cookie, adjust the number of bytes allocated. */ |
| if (use_cookie) |
| { |
| /* Update the total size. */ |
| *size = size_binop (PLUS_EXPR, original_size, *cookie_size); |
| if (size_check) |
| { |
| /* Set to (size_t)-1 if the size check fails. */ |
| gcc_assert (size_check != NULL_TREE); |
| *size = fold_build3 (COND_EXPR, sizetype, size_check, |
| *size, TYPE_MAX_VALUE (sizetype)); |
| } |
| /* Update the argument list to reflect the adjusted size. */ |
| (**args)[0] = *size; |
| } |
| else |
| *cookie_size = NULL_TREE; |
| } |
| |
| /* Tell our caller which function we decided to call. */ |
| if (fn) |
| *fn = cand->fn; |
| |
| /* Build the CALL_EXPR. */ |
| return build_over_call (cand, LOOKUP_NORMAL, complain); |
| } |
| |
| /* Build a new call to operator(). This may change ARGS. */ |
| |
| static tree |
| build_op_call_1 (tree obj, vec<tree, va_gc> **args, tsubst_flags_t complain) |
| { |
| struct z_candidate *candidates = 0, *cand; |
| tree fns, convs, first_mem_arg = NULL_TREE; |
| bool any_viable_p; |
| tree result = NULL_TREE; |
| void *p; |
| |
| obj = mark_lvalue_use (obj); |
| |
| if (error_operand_p (obj)) |
| return error_mark_node; |
| |
| tree type = TREE_TYPE (obj); |
| |
| obj = prep_operand (obj); |
| |
| if (TYPE_PTRMEMFUNC_P (type)) |
| { |
| if (complain & tf_error) |
| /* It's no good looking for an overloaded operator() on a |
| pointer-to-member-function. */ |
| error ("pointer-to-member function %qE cannot be called without " |
| "an object; consider using %<.*%> or %<->*%>", obj); |
| return error_mark_node; |
| } |
| |
| if (TYPE_BINFO (type)) |
| { |
| fns = lookup_fnfields (TYPE_BINFO (type), call_op_identifier, 1); |
| if (fns == error_mark_node) |
| return error_mark_node; |
| } |
| else |
| fns = NULL_TREE; |
| |
| if (args != NULL && *args != NULL) |
| { |
| *args = resolve_args (*args, complain); |
| if (*args == NULL) |
| return error_mark_node; |
| } |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| if (fns) |
| { |
| first_mem_arg = obj; |
| |
| add_candidates (BASELINK_FUNCTIONS (fns), |
| first_mem_arg, *args, NULL_TREE, |
| NULL_TREE, false, |
| BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns), |
| LOOKUP_NORMAL, &candidates, complain); |
| } |
| |
| convs = lookup_conversions (type); |
| |
| for (; convs; convs = TREE_CHAIN (convs)) |
| { |
| tree totype = TREE_TYPE (convs); |
| |
| if (TYPE_PTRFN_P (totype) |
| || TYPE_REFFN_P (totype) |
| || (TYPE_REF_P (totype) |
| && TYPE_PTRFN_P (TREE_TYPE (totype)))) |
| for (ovl_iterator iter (TREE_VALUE (convs)); iter; ++iter) |
| { |
| tree fn = *iter; |
| |
| if (DECL_NONCONVERTING_P (fn)) |
| continue; |
| |
| if (TREE_CODE (fn) == TEMPLATE_DECL) |
| add_template_conv_candidate |
| (&candidates, fn, obj, *args, totype, |
| /*access_path=*/NULL_TREE, |
| /*conversion_path=*/NULL_TREE, complain); |
| else |
| add_conv_candidate (&candidates, fn, obj, |
| *args, /*conversion_path=*/NULL_TREE, |
| /*access_path=*/NULL_TREE, complain); |
| } |
| } |
| |
| /* Be strict here because if we choose a bad conversion candidate, the |
| errors we get won't mention the call context. */ |
| candidates = splice_viable (candidates, true, &any_viable_p); |
| if (!any_viable_p) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), |
| build_tree_list_vec (*args)); |
| print_z_candidates (location_of (TREE_TYPE (obj)), candidates); |
| } |
| result = error_mark_node; |
| } |
| else |
| { |
| cand = tourney (candidates, complain); |
| if (cand == 0) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| error ("call of %<(%T) (%A)%> is ambiguous", |
| TREE_TYPE (obj), build_tree_list_vec (*args)); |
| print_z_candidates (location_of (TREE_TYPE (obj)), candidates); |
| } |
| result = error_mark_node; |
| } |
| else if (TREE_CODE (cand->fn) == FUNCTION_DECL |
| && DECL_OVERLOADED_OPERATOR_P (cand->fn) |
| && DECL_OVERLOADED_OPERATOR_IS (cand->fn, CALL_EXPR)) |
| result = build_over_call (cand, LOOKUP_NORMAL, complain); |
| else |
| { |
| if (TREE_CODE (cand->fn) == FUNCTION_DECL) |
| obj = convert_like_with_context (cand->convs[0], obj, cand->fn, |
| -1, complain); |
| else |
| { |
| gcc_checking_assert (TYPE_P (cand->fn)); |
| obj = convert_like (cand->convs[0], obj, complain); |
| } |
| obj = convert_from_reference (obj); |
| result = cp_build_function_call_vec (obj, args, complain); |
| } |
| } |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return result; |
| } |
| |
| /* Wrapper for above. */ |
| |
| tree |
| build_op_call (tree obj, vec<tree, va_gc> **args, tsubst_flags_t complain) |
| { |
| tree ret; |
| bool subtime = timevar_cond_start (TV_OVERLOAD); |
| ret = build_op_call_1 (obj, args, complain); |
| timevar_cond_stop (TV_OVERLOAD, subtime); |
| return ret; |
| } |
| |
| /* Called by op_error to prepare format strings suitable for the error |
| function. It concatenates a prefix (controlled by MATCH), ERRMSG, |
| and a suffix (controlled by NTYPES). */ |
| |
| static const char * |
| op_error_string (const char *errmsg, int ntypes, bool match) |
| { |
| const char *msg; |
| |
| const char *msgp = concat (match ? G_("ambiguous overload for ") |
| : G_("no match for "), errmsg, NULL); |
| |
| if (ntypes == 3) |
| msg = concat (msgp, G_(" (operand types are %qT, %qT, and %qT)"), NULL); |
| else if (ntypes == 2) |
| msg = concat (msgp, G_(" (operand types are %qT and %qT)"), NULL); |
| else |
| msg = concat (msgp, G_(" (operand type is %qT)"), NULL); |
| |
| return msg; |
| } |
| |
| static void |
| op_error (const op_location_t &loc, |
| enum tree_code code, enum tree_code code2, |
| tree arg1, tree arg2, tree arg3, bool match) |
| { |
| bool assop = code == MODIFY_EXPR; |
| const char *opname = OVL_OP_INFO (assop, assop ? code2 : code)->name; |
| |
| switch (code) |
| { |
| case COND_EXPR: |
| if (flag_diagnostics_show_caret) |
| error_at (loc, op_error_string (G_("ternary %<operator?:%>"), |
| 3, match), |
| TREE_TYPE (arg1), TREE_TYPE (arg2), TREE_TYPE (arg3)); |
| else |
| error_at (loc, op_error_string (G_("ternary %<operator?:%> " |
| "in %<%E ? %E : %E%>"), 3, match), |
| arg1, arg2, arg3, |
| TREE_TYPE (arg1), TREE_TYPE (arg2), TREE_TYPE (arg3)); |
| break; |
| |
| case POSTINCREMENT_EXPR: |
| case POSTDECREMENT_EXPR: |
| if (flag_diagnostics_show_caret) |
| error_at (loc, op_error_string (G_("%<operator%s%>"), 1, match), |
| opname, TREE_TYPE (arg1)); |
| else |
| error_at (loc, op_error_string (G_("%<operator%s%> in %<%E%s%>"), |
| 1, match), |
| opname, arg1, opname, TREE_TYPE (arg1)); |
| break; |
| |
| case ARRAY_REF: |
| if (flag_diagnostics_show_caret) |
| error_at (loc, op_error_string (G_("%<operator[]%>"), 2, match), |
| TREE_TYPE (arg1), TREE_TYPE (arg2)); |
| else |
| error_at (loc, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"), |
| 2, match), |
| arg1, arg2, TREE_TYPE (arg1), TREE_TYPE (arg2)); |
| break; |
| |
| case REALPART_EXPR: |
| case IMAGPART_EXPR: |
| if (flag_diagnostics_show_caret) |
| error_at (loc, op_error_string (G_("%qs"), 1, match), |
| opname, TREE_TYPE (arg1)); |
| else |
| error_at (loc, op_error_string (G_("%qs in %<%s %E%>"), 1, match), |
| opname, opname, arg1, TREE_TYPE (arg1)); |
| break; |
| |
| case CO_AWAIT_EXPR: |
| if (flag_diagnostics_show_caret) |
| error_at (loc, op_error_string (G_("%<operator %s%>"), 1, match), |
| opname, TREE_TYPE (arg1)); |
| else |
| error_at (loc, op_error_string (G_("%<operator %s%> in %<%s%E%>"), |
| 1, match), |
| opname, opname, arg1, TREE_TYPE (arg1)); |
| break; |
| |
| default: |
| if (arg2) |
| if (flag_diagnostics_show_caret) |
| { |
| binary_op_rich_location richloc (loc, arg1, arg2, true); |
| error_at (&richloc, |
| op_error_string (G_("%<operator%s%>"), 2, match), |
| opname, TREE_TYPE (arg1), TREE_TYPE (arg2)); |
| } |
| else |
| error_at (loc, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"), |
| 2, match), |
| opname, arg1, opname, arg2, |
| TREE_TYPE (arg1), TREE_TYPE (arg2)); |
| else |
| if (flag_diagnostics_show_caret) |
| error_at (loc, op_error_string (G_("%<operator%s%>"), 1, match), |
| opname, TREE_TYPE (arg1)); |
| else |
| error_at (loc, op_error_string (G_("%<operator%s%> in %<%s%E%>"), |
| 1, match), |
| opname, opname, arg1, TREE_TYPE (arg1)); |
| break; |
| } |
| } |
| |
| /* Return the implicit conversion sequence that could be used to |
| convert E1 to E2 in [expr.cond]. */ |
| |
| static conversion * |
| conditional_conversion (tree e1, tree e2, tsubst_flags_t complain) |
| { |
| tree t1 = non_reference (TREE_TYPE (e1)); |
| tree t2 = non_reference (TREE_TYPE (e2)); |
| conversion *conv; |
| bool good_base; |
| |
| /* [expr.cond] |
| |
| If E2 is an lvalue: E1 can be converted to match E2 if E1 can be |
| implicitly converted (clause _conv_) to the type "lvalue reference to |
| T2", subject to the constraint that in the conversion the |
| reference must bind directly (_dcl.init.ref_) to an lvalue. |
| |
| If E2 is an xvalue: E1 can be converted to match E2 if E1 can be |
| implicitly converted to the type "rvalue reference to T2", subject to |
| the constraint that the reference must bind directly. */ |
| if (glvalue_p (e2)) |
| { |
| tree rtype = cp_build_reference_type (t2, !lvalue_p (e2)); |
| conv = implicit_conversion (rtype, |
| t1, |
| e1, |
| /*c_cast_p=*/false, |
| LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND |
| |LOOKUP_ONLYCONVERTING, |
| complain); |
| if (conv && !conv->bad_p) |
| return conv; |
| } |
| |
| /* If E2 is a prvalue or if neither of the conversions above can be done |
| and at least one of the operands has (possibly cv-qualified) class |
| type: */ |
| if (!CLASS_TYPE_P (t1) && !CLASS_TYPE_P (t2)) |
| return NULL; |
| |
| /* [expr.cond] |
| |
| If E1 and E2 have class type, and the underlying class types are |
| the same or one is a base class of the other: E1 can be converted |
| to match E2 if the class of T2 is the same type as, or a base |
| class of, the class of T1, and the cv-qualification of T2 is the |
| same cv-qualification as, or a greater cv-qualification than, the |
| cv-qualification of T1. If the conversion is applied, E1 is |
| changed to an rvalue of type T2 that still refers to the original |
| source class object (or the appropriate subobject thereof). */ |
| if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2) |
| && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2))) |
| { |
| if (good_base && at_least_as_qualified_p (t2, t1)) |
| { |
| conv = build_identity_conv (t1, e1); |
| if (!same_type_p (TYPE_MAIN_VARIANT (t1), |
| TYPE_MAIN_VARIANT (t2))) |
| conv = build_conv (ck_base, t2, conv); |
| else |
| conv = build_conv (ck_rvalue, t2, conv); |
| return conv; |
| } |
| else |
| return NULL; |
| } |
| else |
| /* [expr.cond] |
| |
| Otherwise: E1 can be converted to match E2 if E1 can be implicitly |
| converted to the type that expression E2 would have if E2 were |
| converted to an rvalue (or the type it has, if E2 is an rvalue). */ |
| return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false, |
| LOOKUP_IMPLICIT, complain); |
| } |
| |
| /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three |
| arguments to the conditional expression. */ |
| |
| static tree |
| build_conditional_expr_1 (const op_location_t &loc, |
| tree arg1, tree arg2, tree arg3, |
| tsubst_flags_t complain) |
| { |
| tree arg2_type; |
| tree arg3_type; |
| tree result = NULL_TREE; |
| tree result_type = NULL_TREE; |
| bool is_glvalue = true; |
| struct z_candidate *candidates = 0; |
| struct z_candidate *cand; |
| void *p; |
| tree orig_arg2, orig_arg3; |
| |
| /* As a G++ extension, the second argument to the conditional can be |
| omitted. (So that `a ? : c' is roughly equivalent to `a ? a : |
| c'.) If the second operand is omitted, make sure it is |
| calculated only once. */ |
| if (!arg2) |
| { |
| if (complain & tf_error) |
| pedwarn (loc, OPT_Wpedantic, |
| "ISO C++ forbids omitting the middle term of " |
| "a %<?:%> expression"); |
| |
| if ((complain & tf_warning) && !truth_value_p (TREE_CODE (arg1))) |
| warn_for_omitted_condop (loc, arg1); |
| |
| /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */ |
| if (glvalue_p (arg1)) |
| { |
| arg1 = cp_stabilize_reference (arg1); |
| arg2 = arg1 = prevent_lifetime_extension (arg1); |
| } |
| else |
| arg2 = arg1 = cp_save_expr (arg1); |
| } |
| |
| /* If something has already gone wrong, just pass that fact up the |
| tree. */ |
| if (error_operand_p (arg1) |
| || error_operand_p (arg2) |
| || error_operand_p (arg3)) |
| return error_mark_node; |
| |
| orig_arg2 = arg2; |
| orig_arg3 = arg3; |
| |
| if (gnu_vector_type_p (TREE_TYPE (arg1)) |
| && VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1))) |
| { |
| tree arg1_type = TREE_TYPE (arg1); |
| |
| /* If arg1 is another cond_expr choosing between -1 and 0, |
| then we can use its comparison. It may help to avoid |
| additional comparison, produce more accurate diagnostics |
| and enables folding. */ |
| if (TREE_CODE (arg1) == VEC_COND_EXPR |
| && integer_minus_onep (TREE_OPERAND (arg1, 1)) |
| && integer_zerop (TREE_OPERAND (arg1, 2))) |
| arg1 = TREE_OPERAND (arg1, 0); |
| |
| arg1 = force_rvalue (arg1, complain); |
| arg2 = force_rvalue (arg2, complain); |
| arg3 = force_rvalue (arg3, complain); |
| |
| /* force_rvalue can return error_mark on valid arguments. */ |
| if (error_operand_p (arg1) |
| || error_operand_p (arg2) |
| || error_operand_p (arg3)) |
| return error_mark_node; |
| |
| arg2_type = TREE_TYPE (arg2); |
| arg3_type = TREE_TYPE (arg3); |
| |
| if (!VECTOR_TYPE_P (arg2_type) |
| && !VECTOR_TYPE_P (arg3_type)) |
| { |
| /* Rely on the error messages of the scalar version. */ |
| tree scal = build_conditional_expr_1 (loc, integer_one_node, |
| orig_arg2, orig_arg3, complain); |
| if (scal == error_mark_node) |
| return error_mark_node; |
| tree stype = TREE_TYPE (scal); |
| tree ctype = TREE_TYPE (arg1_type); |
| if (TYPE_SIZE (stype) != TYPE_SIZE (ctype) |
| || (!INTEGRAL_TYPE_P (stype) && !SCALAR_FLOAT_TYPE_P (stype))) |
| { |
| if (complain & tf_error) |
| error_at (loc, "inferred scalar type %qT is not an integer or " |
| "floating-point type of the same size as %qT", stype, |
| COMPARISON_CLASS_P (arg1) |
| ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1, 0))) |
| : ctype); |
| return error_mark_node; |
| } |
| |
| tree vtype = build_opaque_vector_type (stype, |
| TYPE_VECTOR_SUBPARTS (arg1_type)); |
| /* We could pass complain & tf_warning to unsafe_conversion_p, |
| but the warnings (like Wsign-conversion) have already been |
| given by the scalar build_conditional_expr_1. We still check |
| unsafe_conversion_p to forbid truncating long long -> float. */ |
| if (unsafe_conversion_p (stype, arg2, NULL_TREE, false)) |
| { |
| if (complain & tf_error) |
| error_at (loc, "conversion of scalar %qH to vector %qI " |
| "involves truncation", arg2_type, vtype); |
| return error_mark_node; |
| } |
| if (unsafe_conversion_p (stype, arg3, NULL_TREE, false)) |
| { |
| if (complain & tf_error) |
| error_at (loc, "conversion of scalar %qH to vector %qI " |
| "involves truncation", arg3_type, vtype); |
| return error_mark_node; |
| } |
| |
| arg2 = cp_convert (stype, arg2, complain); |
| arg2 = save_expr (arg2); |
| arg2 = build_vector_from_val (vtype, arg2); |
| arg2_type = vtype; |
| arg3 = cp_convert (stype, arg3, complain); |
| arg3 = save_expr (arg3); |
| arg3 = build_vector_from_val (vtype, arg3); |
| arg3_type = vtype; |
| } |
| |
| if ((gnu_vector_type_p (arg2_type) && !VECTOR_TYPE_P (arg3_type)) |
| || (gnu_vector_type_p (arg3_type) && !VECTOR_TYPE_P (arg2_type))) |
| { |
| enum stv_conv convert_flag = |
| scalar_to_vector (loc, VEC_COND_EXPR, arg2, arg3, |
| complain & tf_error); |
| |
| switch (convert_flag) |
| { |
| case stv_error: |
| return error_mark_node; |
| case stv_firstarg: |
| { |
| arg2 = save_expr (arg2); |
| arg2 = convert (TREE_TYPE (arg3_type), arg2); |
| arg2 = build_vector_from_val (arg3_type, arg2); |
| arg2_type = TREE_TYPE (arg2); |
| break; |
| } |
| case stv_secondarg: |
| { |
| arg3 = save_expr (arg3); |
| arg3 = convert (TREE_TYPE (arg2_type), arg3); |
| arg3 = build_vector_from_val (arg2_type, arg3); |
| arg3_type = TREE_TYPE (arg3); |
| break; |
| } |
| default: |
| break; |
| } |
| } |
| |
| if (!gnu_vector_type_p (arg2_type) |
| || !gnu_vector_type_p (arg3_type) |
| || !same_type_p (arg2_type, arg3_type) |
| || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type), |
| TYPE_VECTOR_SUBPARTS (arg2_type)) |
| || TYPE_SIZE (arg1_type) != TYPE_SIZE (arg2_type)) |
| { |
| if (complain & tf_error) |
| error_at (loc, |
| "incompatible vector types in conditional expression: " |
| "%qT, %qT and %qT", TREE_TYPE (arg1), |
| TREE_TYPE (orig_arg2), TREE_TYPE (orig_arg3)); |
| return error_mark_node; |
| } |
| |
| if (!COMPARISON_CLASS_P (arg1)) |
| { |
| tree cmp_type = truth_type_for (arg1_type); |
| arg1 = build2 (NE_EXPR, cmp_type, arg1, build_zero_cst (arg1_type)); |
| } |
| return build3_loc (loc, VEC_COND_EXPR, arg2_type, arg1, arg2, arg3); |
| } |
| |
| /* [expr.cond] |
| |
| The first expression is implicitly converted to bool (clause |
| _conv_). */ |
| arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain, |
| LOOKUP_NORMAL); |
| if (error_operand_p (arg1)) |
| return error_mark_node; |
| |
| /* [expr.cond] |
| |
| If either the second or the third operand has type (possibly |
| cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_), |
| array-to-pointer (_conv.array_), and function-to-pointer |
| (_conv.func_) standard conversions are performed on the second |
| and third operands. */ |
| arg2_type = unlowered_expr_type (arg2); |
| arg3_type = unlowered_expr_type (arg3); |
| if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type)) |
| { |
| /* 'void' won't help in resolving an overloaded expression on the |
| other side, so require it to resolve by itself. */ |
| if (arg2_type == unknown_type_node) |
| { |
| arg2 = resolve_nondeduced_context_or_error (arg2, complain); |
| arg2_type = TREE_TYPE (arg2); |
| } |
| if (arg3_type == unknown_type_node) |
| { |
| arg3 = resolve_nondeduced_context_or_error (arg3, complain); |
| arg3_type = TREE_TYPE (arg3); |
| } |
| |
| /* [expr.cond] |
| |
| One of the following shall hold: |
| |
| --The second or the third operand (but not both) is a |
| throw-expression (_except.throw_); the result is of the type |
| and value category of the other. |
| |
| --Both the second and the third operands have type void; the |
| result is of type void and is a prvalue. */ |
| if (TREE_CODE (arg2) == THROW_EXPR |
| && TREE_CODE (arg3) != THROW_EXPR) |
| { |
| result_type = arg3_type; |
| is_glvalue = glvalue_p (arg3); |
| } |
| else if (TREE_CODE (arg2) != THROW_EXPR |
| && TREE_CODE (arg3) == THROW_EXPR) |
| { |
| result_type = arg2_type; |
| is_glvalue = glvalue_p (arg2); |
| } |
| else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type)) |
| { |
| result_type = void_type_node; |
| is_glvalue = false; |
| } |
| else |
| { |
| if (complain & tf_error) |
| { |
| if (VOID_TYPE_P (arg2_type)) |
| error_at (cp_expr_loc_or_loc (arg3, loc), |
| "second operand to the conditional operator " |
| "is of type %<void%>, but the third operand is " |
| "neither a throw-expression nor of type %<void%>"); |
| else |
| error_at (cp_expr_loc_or_loc (arg2, loc), |
| "third operand to the conditional operator " |
| "is of type %<void%>, but the second operand is " |
| "neither a throw-expression nor of type %<void%>"); |
| } |
| return error_mark_node; |
| } |
| |
| goto valid_operands; |
| } |
| /* [expr.cond] |
| |
| Otherwise, if the second and third operand have different types, |
| and either has (possibly cv-qualified) class type, or if both are |
| glvalues of the same value category and the same type except for |
| cv-qualification, an attempt is made to convert each of those operands |
| to the type of the other. */ |
| else if (!same_type_p (arg2_type, arg3_type) |
| && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type) |
| || (same_type_ignoring_top_level_qualifiers_p (arg2_type, |
| arg3_type) |
| && glvalue_p (arg2) && glvalue_p (arg3) |
| && lvalue_p (arg2) == lvalue_p (arg3)))) |
| { |
| conversion *conv2; |
| conversion *conv3; |
| bool converted = false; |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| conv2 = conditional_conversion (arg2, arg3, complain); |
| conv3 = conditional_conversion (arg3, arg2, complain); |
| |
| /* [expr.cond] |
| |
| If both can be converted, or one can be converted but the |
| conversion is ambiguous, the program is ill-formed. If |
| neither can be converted, the operands are left unchanged and |
| further checking is performed as described below. If exactly |
| one conversion is possible, that conversion is applied to the |
| chosen operand and the converted operand is used in place of |
| the original operand for the remainder of this section. */ |
| if ((conv2 && !conv2->bad_p |
| && conv3 && !conv3->bad_p) |
| || (conv2 && conv2->kind == ck_ambig) |
| || (conv3 && conv3->kind == ck_ambig)) |
| { |
| if (complain & tf_error) |
| { |
| error_at (loc, "operands to %<?:%> have different types " |
| "%qT and %qT", |
| arg2_type, arg3_type); |
| if (conv2 && !conv2->bad_p && conv3 && !conv3->bad_p) |
| inform (loc, " and each type can be converted to the other"); |
| else if (conv2 && conv2->kind == ck_ambig) |
| convert_like (conv2, arg2, complain); |
| else |
| convert_like (conv3, arg3, complain); |
| } |
| result = error_mark_node; |
| } |
| else if (conv2 && !conv2->bad_p) |
| { |
| arg2 = convert_like (conv2, arg2, complain); |
| arg2 = convert_from_reference (arg2); |
| arg2_type = TREE_TYPE (arg2); |
| /* Even if CONV2 is a valid conversion, the result of the |
| conversion may be invalid. For example, if ARG3 has type |
| "volatile X", and X does not have a copy constructor |
| accepting a "volatile X&", then even if ARG2 can be |
| converted to X, the conversion will fail. */ |
| if (error_operand_p (arg2)) |
| result = error_mark_node; |
| converted = true; |
| } |
| else if (conv3 && !conv3->bad_p) |
| { |
| arg3 = convert_like (conv3, arg3, complain); |
| arg3 = convert_from_reference (arg3); |
| arg3_type = TREE_TYPE (arg3); |
| if (error_operand_p (arg3)) |
| result = error_mark_node; |
| converted = true; |
| } |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| if (result) |
| return result; |
| |
| /* If, after the conversion, both operands have class type, |
| treat the cv-qualification of both operands as if it were the |
| union of the cv-qualification of the operands. |
| |
| The standard is not clear about what to do in this |
| circumstance. For example, if the first operand has type |
| "const X" and the second operand has a user-defined |
| conversion to "volatile X", what is the type of the second |
| operand after this step? Making it be "const X" (matching |
| the first operand) seems wrong, as that discards the |
| qualification without actually performing a copy. Leaving it |
| as "volatile X" seems wrong as that will result in the |
| conditional expression failing altogether, even though, |
| according to this step, the one operand could be converted to |
| the type of the other. */ |
| if (converted |
| && CLASS_TYPE_P (arg2_type) |
| && cp_type_quals (arg2_type) != cp_type_quals (arg3_type)) |
| arg2_type = arg3_type = |
| cp_build_qualified_type (arg2_type, |
| cp_type_quals (arg2_type) |
| | cp_type_quals (arg3_type)); |
| } |
| |
| /* [expr.cond] |
| |
| If the second and third operands are glvalues of the same value |
| category and have the same type, the result is of that type and |
| value category. */ |
| if (((lvalue_p (arg2) && lvalue_p (arg3)) |
| || (xvalue_p (arg2) && xvalue_p (arg3))) |
| && same_type_p (arg2_type, arg3_type)) |
| { |
| result_type = arg2_type; |
| goto valid_operands; |
| } |
| |
| /* [expr.cond] |
| |
| Otherwise, the result is an rvalue. If the second and third |
| operand do not have the same type, and either has (possibly |
| cv-qualified) class type, overload resolution is used to |
| determine the conversions (if any) to be applied to the operands |
| (_over.match.oper_, _over.built_). */ |
| is_glvalue = false; |
| if (!same_type_p (arg2_type, arg3_type) |
| && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type))) |
| { |
| releasing_vec args; |
| conversion *conv; |
| bool any_viable_p; |
| |
| /* Rearrange the arguments so that add_builtin_candidate only has |
| to know about two args. In build_builtin_candidate, the |
| arguments are unscrambled. */ |
| args->quick_push (arg2); |
| args->quick_push (arg3); |
| args->quick_push (arg1); |
| add_builtin_candidates (&candidates, |
| COND_EXPR, |
| NOP_EXPR, |
| ovl_op_identifier (false, COND_EXPR), |
| args, |
| LOOKUP_NORMAL, complain); |
| |
| /* [expr.cond] |
| |
| If the overload resolution fails, the program is |
| ill-formed. */ |
| candidates = splice_viable (candidates, false, &any_viable_p); |
| if (!any_viable_p) |
| { |
| if (complain & tf_error) |
| error_at (loc, "operands to %<?:%> have different types %qT and %qT", |
| arg2_type, arg3_type); |
| return error_mark_node; |
| } |
| cand = tourney (candidates, complain); |
| if (!cand) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| op_error (loc, COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE); |
| print_z_candidates (loc, candidates); |
| } |
| return error_mark_node; |
| } |
| |
| /* [expr.cond] |
| |
| Otherwise, the conversions thus determined are applied, and |
| the converted operands are used in place of the original |
| operands for the remainder of this section. */ |
| conv = cand->convs[0]; |
| arg1 = convert_like (conv, arg1, complain); |
| conv = cand->convs[1]; |
| arg2 = convert_like (conv, arg2, complain); |
| arg2_type = TREE_TYPE (arg2); |
| conv = cand->convs[2]; |
| arg3 = convert_like (conv, arg3, complain); |
| arg3_type = TREE_TYPE (arg3); |
| } |
| |
| /* [expr.cond] |
| |
| Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_), |
| and function-to-pointer (_conv.func_) standard conversions are |
| performed on the second and third operands. |
| |
| We need to force the lvalue-to-rvalue conversion here for class types, |
| so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues |
| that isn't wrapped with a TARGET_EXPR plays havoc with exception |
| regions. */ |
| |
| arg2 = force_rvalue (arg2, complain); |
| if (!CLASS_TYPE_P (arg2_type)) |
| arg2_type = TREE_TYPE (arg2); |
| |
| arg3 = force_rvalue (arg3, complain); |
| if (!CLASS_TYPE_P (arg3_type)) |
| arg3_type = TREE_TYPE (arg3); |
| |
| if (arg2 == error_mark_node || arg3 == error_mark_node) |
| return error_mark_node; |
| |
| /* [expr.cond] |
| |
| After those conversions, one of the following shall hold: |
| |
| --The second and third operands have the same type; the result is of |
| that type. */ |
| if (same_type_p (arg2_type, arg3_type)) |
| result_type = arg2_type; |
| /* [expr.cond] |
| |
| --The second and third operands have arithmetic or enumeration |
| type; the usual arithmetic conversions are performed to bring |
| them to a common type, and the result is of that type. */ |
| else if ((ARITHMETIC_TYPE_P (arg2_type) |
| || UNSCOPED_ENUM_P (arg2_type)) |
| && (ARITHMETIC_TYPE_P (arg3_type) |
| || UNSCOPED_ENUM_P (arg3_type))) |
| { |
| /* In this case, there is always a common type. */ |
| result_type = type_after_usual_arithmetic_conversions (arg2_type, |
| arg3_type); |
| if (complain & tf_warning) |
| do_warn_double_promotion (result_type, arg2_type, arg3_type, |
| "implicit conversion from %qH to %qI to " |
| "match other result of conditional", |
| loc); |
| |
| if (TREE_CODE (arg2_type) == ENUMERAL_TYPE |
| && TREE_CODE (arg3_type) == ENUMERAL_TYPE) |
| { |
| tree stripped_orig_arg2 = tree_strip_any_location_wrapper (orig_arg2); |
| tree stripped_orig_arg3 = tree_strip_any_location_wrapper (orig_arg3); |
| if (TREE_CODE (stripped_orig_arg2) == CONST_DECL |
| && TREE_CODE (stripped_orig_arg3) == CONST_DECL |
| && (DECL_CONTEXT (stripped_orig_arg2) |
| == DECL_CONTEXT (stripped_orig_arg3))) |
| /* Two enumerators from the same enumeration can have different |
| types when the enumeration is still being defined. */; |
| else if (complain & tf_warning) |
| warning_at (loc, OPT_Wenum_compare, "enumerated mismatch " |
| "in conditional expression: %qT vs %qT", |
| arg2_type, arg3_type); |
| } |
| else if (extra_warnings |
| && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE |
| && !same_type_p (arg3_type, type_promotes_to (arg2_type))) |
| || (TREE_CODE (arg3_type) == ENUMERAL_TYPE |
| && !same_type_p (arg2_type, |
| type_promotes_to (arg3_type))))) |
| { |
| if (complain & tf_warning) |
| warning_at (loc, OPT_Wextra, "enumerated and non-enumerated " |
| "type in conditional expression"); |
| } |
| |
| arg2 = perform_implicit_conversion (result_type, arg2, complain); |
| arg3 = perform_implicit_conversion (result_type, arg3, complain); |
| } |
| /* [expr.cond] |
| |
| --The second and third operands have pointer type, or one has |
| pointer type and the other is a null pointer constant; pointer |
| conversions (_conv.ptr_) and qualification conversions |
| (_conv.qual_) are performed to bring them to their composite |
| pointer type (_expr.rel_). The result is of the composite |
| pointer type. |
| |
| --The second and third operands have pointer to member type, or |
| one has pointer to member type and the other is a null pointer |
| constant; pointer to member conversions (_conv.mem_) and |
| qualification conversions (_conv.qual_) are performed to bring |
| them to a common type, whose cv-qualification shall match the |
| cv-qualification of either the second or the third operand. |
| The result is of the common type. */ |
| else if ((null_ptr_cst_p (arg2) |
| && TYPE_PTR_OR_PTRMEM_P (arg3_type)) |
| || (null_ptr_cst_p (arg3) |
| && TYPE_PTR_OR_PTRMEM_P (arg2_type)) |
| || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type)) |
| || (TYPE_PTRDATAMEM_P (arg2_type) && TYPE_PTRDATAMEM_P (arg3_type)) |
| || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type))) |
| { |
| result_type = composite_pointer_type (loc, |
| arg2_type, arg3_type, arg2, |
| arg3, CPO_CONDITIONAL_EXPR, |
| complain); |
| if (result_type == error_mark_node) |
| return error_mark_node; |
| arg2 = perform_implicit_conversion (result_type, arg2, complain); |
| arg3 = perform_implicit_conversion (result_type, arg3, complain); |
| } |
| |
| if (!result_type) |
| { |
| if (complain & tf_error) |
| error_at (loc, "operands to %<?:%> have different types %qT and %qT", |
| arg2_type, arg3_type); |
| return error_mark_node; |
| } |
| |
| if (arg2 == error_mark_node || arg3 == error_mark_node) |
| return error_mark_node; |
| |
| valid_operands: |
| if (processing_template_decl && is_glvalue) |
| { |
| /* Let lvalue_kind know this was a glvalue. */ |
| tree arg = (result_type == arg2_type ? arg2 : arg3); |
| result_type = cp_build_reference_type (result_type, xvalue_p (arg)); |
| } |
| |
| result = build3_loc (loc, COND_EXPR, result_type, arg1, arg2, arg3); |
| |
| /* If the ARG2 and ARG3 are the same and don't have side-effects, |
| warn here, because the COND_EXPR will be turned into ARG2. */ |
| if (warn_duplicated_branches |
| && (complain & tf_warning) |
| && (arg2 == arg3 || operand_equal_p (arg2, arg3, 0))) |
| warning_at (EXPR_LOCATION (result), OPT_Wduplicated_branches, |
| "this condition has identical branches"); |
| |
| /* We can't use result_type below, as fold might have returned a |
| throw_expr. */ |
| |
| if (!is_glvalue) |
| { |
| /* Expand both sides into the same slot, hopefully the target of |
| the ?: expression. We used to check for TARGET_EXPRs here, |
| but now we sometimes wrap them in NOP_EXPRs so the test would |
| fail. */ |
| if (CLASS_TYPE_P (TREE_TYPE (result))) |
| result = get_target_expr_sfinae (result, complain); |
| /* If this expression is an rvalue, but might be mistaken for an |
| lvalue, we must add a NON_LVALUE_EXPR. */ |
| result = rvalue (result); |
| } |
| else |
| result = force_paren_expr (result); |
| |
| return result; |
| } |
| |
| /* Wrapper for above. */ |
| |
| tree |
| build_conditional_expr (const op_location_t &loc, |
| tree arg1, tree arg2, tree arg3, |
| tsubst_flags_t complain) |
| { |
| tree ret; |
| bool subtime = timevar_cond_start (TV_OVERLOAD); |
| ret = build_conditional_expr_1 (loc, arg1, arg2, arg3, complain); |
| timevar_cond_stop (TV_OVERLOAD, subtime); |
| return ret; |
| } |
| |
| /* OPERAND is an operand to an expression. Perform necessary steps |
| required before using it. If OPERAND is NULL_TREE, NULL_TREE is |
| returned. */ |
| |
| static tree |
| prep_operand (tree operand) |
| { |
| if (operand) |
| { |
| if (CLASS_TYPE_P (TREE_TYPE (operand)) |
| && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand))) |
| /* Make sure the template type is instantiated now. */ |
| instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand))); |
| } |
| |
| return operand; |
| } |
| |
| /* Add each of the viable functions in FNS (a FUNCTION_DECL or |
| OVERLOAD) to the CANDIDATES, returning an updated list of |
| CANDIDATES. The ARGS are the arguments provided to the call; |
| if FIRST_ARG is non-null it is the implicit object argument, |
| otherwise the first element of ARGS is used if needed. The |
| EXPLICIT_TARGS are explicit template arguments provided. |
| TEMPLATE_ONLY is true if only template functions should be |
| considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for |
| add_function_candidate. */ |
| |
| static void |
| add_candidates (tree fns, tree first_arg, const vec<tree, va_gc> *args, |
| tree return_type, |
| tree explicit_targs, bool template_only, |
| tree conversion_path, tree access_path, |
| int flags, |
| struct z_candidate **candidates, |
| tsubst_flags_t complain) |
| { |
| tree ctype; |
| const vec<tree, va_gc> *non_static_args; |
| bool check_list_ctor = false; |
| bool check_converting = false; |
| unification_kind_t strict; |
| |
| if (!fns) |
| return; |
| |
| /* Precalculate special handling of constructors and conversion ops. */ |
| tree fn = OVL_FIRST (fns); |
| if (DECL_CONV_FN_P (fn)) |
| { |
| check_list_ctor = false; |
| check_converting = (flags & LOOKUP_ONLYCONVERTING) != 0; |
| if (flags & LOOKUP_NO_CONVERSION) |
| /* We're doing return_type(x). */ |
| strict = DEDUCE_CONV; |
| else |
| /* We're doing x.operator return_type(). */ |
| strict = DEDUCE_EXACT; |
| /* [over.match.funcs] For conversion functions, the function |
| is considered to be a member of the class of the implicit |
| object argument for the purpose of defining the type of |
| the implicit object parameter. */ |
| ctype = TYPE_MAIN_VARIANT (TREE_TYPE (first_arg)); |
| } |
| else |
| { |
| if (DECL_CONSTRUCTOR_P (fn)) |
| { |
| check_list_ctor = (flags & LOOKUP_LIST_ONLY) != 0; |
| /* For list-initialization we consider explicit constructors |
| and complain if one is chosen. */ |
| check_converting |
| = ((flags & (LOOKUP_ONLYCONVERTING|LOOKUP_LIST_INIT_CTOR)) |
| == LOOKUP_ONLYCONVERTING); |
| } |
| strict = DEDUCE_CALL; |
| ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE; |
| } |
| |
| if (first_arg) |
| non_static_args = args; |
| else |
| /* Delay creating the implicit this parameter until it is needed. */ |
| non_static_args = NULL; |
| |
| for (lkp_iterator iter (fns); iter; ++iter) |
| { |
| fn = *iter; |
| |
| if (check_converting && DECL_NONCONVERTING_P (fn)) |
| continue; |
| if (check_list_ctor && !is_list_ctor (fn)) |
| continue; |
| |
| tree fn_first_arg = NULL_TREE; |
| const vec<tree, va_gc> *fn_args = args; |
| |
| if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)) |
| { |
| /* Figure out where the object arg comes from. If this |
| function is a non-static member and we didn't get an |
| implicit object argument, move it out of args. */ |
| if (first_arg == NULL_TREE) |
| { |
| unsigned int ix; |
| tree arg; |
| vec<tree, va_gc> *tempvec; |
| vec_alloc (tempvec, args->length () - 1); |
| for (ix = 1; args->iterate (ix, &arg); ++ix) |
| tempvec->quick_push (arg); |
| non_static_args = tempvec; |
| first_arg = (*args)[0]; |
| } |
| |
| fn_first_arg = first_arg; |
| fn_args = non_static_args; |
| } |
| |
| /* Don't bother reversing an operator with two identical parameters. */ |
| else if (vec_safe_length (args) == 2 && (flags & LOOKUP_REVERSED)) |
| { |
| tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn)); |
| if (same_type_p (TREE_VALUE (parmlist), |
| TREE_VALUE (TREE_CHAIN (parmlist)))) |
| continue; |
| } |
| |
| if (TREE_CODE (fn) == TEMPLATE_DECL) |
| add_template_candidate (candidates, |
| fn, |
| ctype, |
| explicit_targs, |
| fn_first_arg, |
| fn_args, |
| return_type, |
| access_path, |
| conversion_path, |
| flags, |
| strict, |
| complain); |
| else if (!template_only) |
| add_function_candidate (candidates, |
| fn, |
| ctype, |
| fn_first_arg, |
| fn_args, |
| access_path, |
| conversion_path, |
| flags, |
| NULL, |
| complain); |
| } |
| } |
| |
| /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first, |
| -1 if the RHS is evaluated first, or 0 if the order is unspecified. */ |
| |
| static int |
| op_is_ordered (tree_code code) |
| { |
| switch (code) |
| { |
| // 5. b @= a |
| case MODIFY_EXPR: |
| return (flag_strong_eval_order > 1 ? -1 : 0); |
| |
| // 6. a[b] |
| case ARRAY_REF: |
| return (flag_strong_eval_order > 1 ? 1 : 0); |
| |
| // 1. a.b |
| // Not overloadable (yet). |
| // 2. a->b |
| // Only one argument. |
| // 3. a->*b |
| case MEMBER_REF: |
| // 7. a << b |
| case LSHIFT_EXPR: |
| // 8. a >> b |
| case RSHIFT_EXPR: |
| // a && b |
| // Predates P0145R3. |
| case TRUTH_ANDIF_EXPR: |
| // a || b |
| // Predates P0145R3. |
| case TRUTH_ORIF_EXPR: |
| // a , b |
| // Predates P0145R3. |
| case COMPOUND_EXPR: |
| return (flag_strong_eval_order ? 1 : 0); |
| |
| default: |
| return 0; |
| } |
| } |
| |
| /* Subroutine of build_new_op_1: Add to CANDIDATES all candidates for the |
| operator indicated by CODE/CODE2. This function calls itself recursively to |
| handle C++20 rewritten comparison operator candidates. */ |
| |
| static tree |
| add_operator_candidates (z_candidate **candidates, |
| tree_code code, tree_code code2, |
| vec<tree, va_gc> *arglist, |
| int flags, tsubst_flags_t complain) |
| { |
| z_candidate *start_candidates = *candidates; |
| bool ismodop = code2 != ERROR_MARK; |
| tree fnname = ovl_op_identifier (ismodop, ismodop ? code2 : code); |
| |
| /* LOOKUP_REWRITTEN is set when we're looking for the == or <=> operator to |
| rewrite from, and also when we're looking for the e.g. < operator to use |
| on the result of <=>. In the latter case, we don't want the flag set in |
| the candidate, we just want to suppress looking for rewrites. */ |
| bool rewritten = (flags & LOOKUP_REWRITTEN); |
| if (rewritten && code != EQ_EXPR && code != SPACESHIP_EXPR) |
| flags &= ~LOOKUP_REWRITTEN; |
| |
| bool memonly = false; |
| switch (code) |
| { |
| /* =, ->, [], () must be non-static member functions. */ |
| case MODIFY_EXPR: |
| if (code2 != NOP_EXPR) |
| break; |
| /* FALLTHRU */ |
| case COMPONENT_REF: |
| case ARRAY_REF: |
| memonly = true; |
| break; |
| |
| default: |
| break; |
| } |
| |
| /* Add namespace-scope operators to the list of functions to |
| consider. */ |
| if (!memonly) |
| { |
| tree fns = lookup_name_real (fnname, 0, 1, /*block_p=*/true, 0, 0); |
| fns = lookup_arg_dependent (fnname, fns, arglist); |
| add_candidates (fns, NULL_TREE, arglist, NULL_TREE, |
| NULL_TREE, false, NULL_TREE, NULL_TREE, |
| flags, candidates, complain); |
| } |
| |
| /* Add class-member operators to the candidate set. */ |
| tree arg1_type = TREE_TYPE ((*arglist)[0]); |
| unsigned nargs = arglist->length () > 1 ? 2 : 1; |
| tree arg2_type = nargs > 1 ? TREE_TYPE ((*arglist)[1]) : NULL_TREE; |
| if (CLASS_TYPE_P (arg1_type)) |
| { |
| tree fns = lookup_fnfields (arg1_type, fnname, 1); |
| if (fns == error_mark_node) |
| return error_mark_node; |
| if (fns) |
| add_candidates (BASELINK_FUNCTIONS (fns), |
| NULL_TREE, arglist, NULL_TREE, |
| NULL_TREE, false, |
| BASELINK_BINFO (fns), |
| BASELINK_ACCESS_BINFO (fns), |
| flags, candidates, complain); |
| } |
| /* Per [over.match.oper]3.2, if no operand has a class type, then |
| only non-member functions that have type T1 or reference to |
| cv-qualified-opt T1 for the first argument, if the first argument |
| has an enumeration type, or T2 or reference to cv-qualified-opt |
| T2 for the second argument, if the second argument has an |
| enumeration type. Filter out those that don't match. */ |
| else if (! arg2_type || ! CLASS_TYPE_P (arg2_type)) |
| { |
| struct z_candidate **candp, **next; |
| |
| for (candp = candidates; *candp != start_candidates; candp = next) |
| { |
| unsigned i; |
| z_candidate *cand = *candp; |
| next = &cand->next; |
| |
| tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (cand->fn)); |
| |
| for (i = 0; i < nargs; ++i) |
| { |
| tree parmtype = TREE_VALUE (parmlist); |
| tree argtype = unlowered_expr_type ((*arglist)[i]); |
| |
| if (TYPE_REF_P (parmtype)) |
| parmtype = TREE_TYPE (parmtype); |
| if (TREE_CODE (argtype) == ENUMERAL_TYPE |
| && (same_type_ignoring_top_level_qualifiers_p |
| (argtype, parmtype))) |
| break; |
| |
| parmlist = TREE_CHAIN (parmlist); |
| } |
| |
| /* No argument has an appropriate type, so remove this |
| candidate function from the list. */ |
| if (i == nargs) |
| { |
| *candp = cand->next; |
| next = candp; |
| } |
| } |
| } |
| |
| if (!rewritten) |
| { |
| /* The standard says to rewrite built-in candidates, too, |
| but there's no point. */ |
| add_builtin_candidates (candidates, code, code2, fnname, arglist, |
| flags, complain); |
| |
| /* Maybe add C++20 rewritten comparison candidates. */ |
| tree_code rewrite_code = ERROR_MARK; |
| if (cxx_dialect >= cxx2a |
| && nargs == 2 |
| && (OVERLOAD_TYPE_P (arg1_type) || OVERLOAD_TYPE_P (arg2_type))) |
| switch (code) |
| { |
| case LT_EXPR: |
| case LE_EXPR: |
| case GT_EXPR: |
| case GE_EXPR: |
| case SPACESHIP_EXPR: |
| rewrite_code = SPACESHIP_EXPR; |
| break; |
| |
| case NE_EXPR: |
| case EQ_EXPR: |
| rewrite_code = EQ_EXPR; |
| break; |
| |
| default:; |
| } |
| |
| if (rewrite_code) |
| { |
| flags |= LOOKUP_REWRITTEN; |
| if (rewrite_code != code) |
| /* Add rewritten candidates in same order. */ |
| add_operator_candidates (candidates, rewrite_code, ERROR_MARK, |
| arglist, flags, complain); |
| |
| z_candidate *save_cand = *candidates; |
| |
| /* Add rewritten candidates in reverse order. */ |
| flags |= LOOKUP_REVERSED; |
| vec<tree,va_gc> *revlist = make_tree_vector (); |
| revlist->quick_push ((*arglist)[1]); |
| revlist->quick_push ((*arglist)[0]); |
| add_operator_candidates (candidates, rewrite_code, ERROR_MARK, |
| revlist, flags, complain); |
| |
| /* Release the vec if we didn't add a candidate that uses it. */ |
| for (z_candidate *c = *candidates; c != save_cand; c = c->next) |
| if (c->args == revlist) |
| { |
| revlist = NULL; |
| break; |
| } |
| release_tree_vector (revlist); |
| } |
| } |
| |
| return NULL_TREE; |
| } |
| |
| static tree |
| build_new_op_1 (const op_location_t &loc, enum tree_code code, int flags, |
| tree arg1, tree arg2, tree arg3, tree *overload, |
| tsubst_flags_t complain) |
| { |
| struct z_candidate *candidates = 0, *cand; |
| vec<tree, va_gc> *arglist; |
| tree result = NULL_TREE; |
| bool result_valid_p = false; |
| enum tree_code code2 = ERROR_MARK; |
| enum tree_code code_orig_arg1 = ERROR_MARK; |
| enum tree_code code_orig_arg2 = ERROR_MARK; |
| conversion *conv; |
| void *p; |
| bool strict_p; |
| bool any_viable_p; |
| |
| if (error_operand_p (arg1) |
| || error_operand_p (arg2) |
| || error_operand_p (arg3)) |
| return error_mark_node; |
| |
| bool ismodop = code == MODIFY_EXPR; |
| if (ismodop) |
| { |
| code2 = TREE_CODE (arg3); |
| arg3 = NULL_TREE; |
| } |
| |
| tree arg1_type = unlowered_expr_type (arg1); |
| tree arg2_type = arg2 ? unlowered_expr_type (arg2) : NULL_TREE; |
| |
| arg1 = prep_operand (arg1); |
| |
| switch (code) |
| { |
| case NEW_EXPR: |
| case VEC_NEW_EXPR: |
| case VEC_DELETE_EXPR: |
| case DELETE_EXPR: |
| /* Use build_op_new_call and build_op_delete_call instead. */ |
| gcc_unreachable (); |
| |
| case CALL_EXPR: |
| /* Use build_op_call instead. */ |
| gcc_unreachable (); |
| |
| case TRUTH_ORIF_EXPR: |
| case TRUTH_ANDIF_EXPR: |
| case TRUTH_AND_EXPR: |
| case TRUTH_OR_EXPR: |
| /* These are saved for the sake of warn_logical_operator. */ |
| code_orig_arg1 = TREE_CODE (arg1); |
| code_orig_arg2 = TREE_CODE (arg2); |
| break; |
| case GT_EXPR: |
| case LT_EXPR: |
| case GE_EXPR: |
| case LE_EXPR: |
| case EQ_EXPR: |
| case NE_EXPR: |
| /* These are saved for the sake of maybe_warn_bool_compare. */ |
| code_orig_arg1 = TREE_CODE (arg1_type); |
| code_orig_arg2 = TREE_CODE (arg2_type); |
| break; |
| |
| default: |
| break; |
| } |
| |
| arg2 = prep_operand (arg2); |
| arg3 = prep_operand (arg3); |
| |
| if (code == COND_EXPR) |
| /* Use build_conditional_expr instead. */ |
| gcc_unreachable (); |
| else if (! OVERLOAD_TYPE_P (arg1_type) |
| && (! arg2 || ! OVERLOAD_TYPE_P (arg2_type))) |
| goto builtin; |
| |
| if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR) |
| { |
| arg2 = integer_zero_node; |
| arg2_type = integer_type_node; |
| } |
| |
| vec_alloc (arglist, 3); |
| arglist->quick_push (arg1); |
| if (arg2 != NULL_TREE) |
| arglist->quick_push (arg2); |
| if (arg3 != NULL_TREE) |
| arglist->quick_push (arg3); |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| result = add_operator_candidates (&candidates, code, code2, arglist, |
| flags, complain); |
| if (result == error_mark_node) |
| goto user_defined_result_ready; |
| |
| switch (code) |
| { |
| case COMPOUND_EXPR: |
| case ADDR_EXPR: |
| /* For these, the built-in candidates set is empty |
| [over.match.oper]/3. We don't want non-strict matches |
| because exact matches are always possible with built-in |
| operators. The built-in candidate set for COMPONENT_REF |
| would be empty too, but since there are no such built-in |
| operators, we accept non-strict matches for them. */ |
| strict_p = true; |
| break; |
| |
| default: |
| strict_p = false; |
| break; |
| } |
| |
| candidates = splice_viable (candidates, strict_p, &any_viable_p); |
| if (!any_viable_p) |
| { |
| switch (code) |
| { |
| case POSTINCREMENT_EXPR: |
| case POSTDECREMENT_EXPR: |
| /* Don't try anything fancy if we're not allowed to produce |
| errors. */ |
| if (!(complain & tf_error)) |
| return error_mark_node; |
| |
| /* Look for an `operator++ (int)'. Pre-1985 C++ didn't |
| distinguish between prefix and postfix ++ and |
| operator++() was used for both, so we allow this with |
| -fpermissive. */ |
| else |
| { |
| tree fnname = ovl_op_identifier (ismodop, ismodop ? code2 : code); |
| const char *msg = (flag_permissive) |
| ? G_("no %<%D(int)%> declared for postfix %qs," |
| " trying prefix operator instead") |
| : G_("no %<%D(int)%> declared for postfix %qs"); |
| permerror (loc, msg, fnname, OVL_OP_INFO (false, code)->name); |
| } |
| |
| if (!flag_permissive) |
| return error_mark_node; |
| |
| if (code == POSTINCREMENT_EXPR) |
| code = PREINCREMENT_EXPR; |
| else |
| code = PREDECREMENT_EXPR; |
| result = build_new_op_1 (loc, code, flags, arg1, NULL_TREE, |
| NULL_TREE, overload, complain); |
| break; |
| |
| /* The caller will deal with these. */ |
| case ADDR_EXPR: |
| case COMPOUND_EXPR: |
| case COMPONENT_REF: |
| case CO_AWAIT_EXPR: |
| result = NULL_TREE; |
| result_valid_p = true; |
| break; |
| |
| default: |
| if (complain & tf_error) |
| { |
| /* If one of the arguments of the operator represents |
| an invalid use of member function pointer, try to report |
| a meaningful error ... */ |
| if (invalid_nonstatic_memfn_p (loc, arg1, tf_error) |
| || invalid_nonstatic_memfn_p (loc, arg2, tf_error) |
| || invalid_nonstatic_memfn_p (loc, arg3, tf_error)) |
| /* We displayed the error message. */; |
| else |
| { |
| /* ... Otherwise, report the more generic |
| "no matching operator found" error */ |
| auto_diagnostic_group d; |
| op_error (loc, code, code2, arg1, arg2, arg3, FALSE); |
| print_z_candidates (loc, candidates); |
| } |
| } |
| result = error_mark_node; |
| break; |
| } |
| } |
| else |
| { |
| cand = tourney (candidates, complain); |
| if (cand == 0) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| op_error (loc, code, code2, arg1, arg2, arg3, TRUE); |
| print_z_candidates (loc, candidates); |
| } |
| result = error_mark_node; |
| } |
| else if (TREE_CODE (cand->fn) == FUNCTION_DECL) |
| { |
| if (overload) |
| *overload = cand->fn; |
| |
| if (resolve_args (arglist, complain) == NULL) |
| result = error_mark_node; |
| else |
| { |
| tsubst_flags_t ocomplain = complain; |
| if (cand->rewritten ()) |
| /* We'll wrap this call in another one. */ |
| ocomplain &= ~tf_decltype; |
| if (cand->reversed ()) |
| { |
| /* We swapped these in add_candidate, swap them back now. */ |
| std::swap (cand->convs[0], cand->convs[1]); |
| if (cand->fn == current_function_decl) |
| warning_at (loc, 0, "in C++20 this comparison calls the " |
| "current function recursively with reversed " |
| "arguments"); |
| } |
| result = build_over_call (cand, LOOKUP_NORMAL, ocomplain); |
| } |
| |
| if (trivial_fn_p (cand->fn) || DECL_IMMEDIATE_FUNCTION_P (cand->fn)) |
| /* There won't be a CALL_EXPR. */; |
| else if (result && result != error_mark_node) |
| { |
| tree call = extract_call_expr (result); |
| CALL_EXPR_OPERATOR_SYNTAX (call) = true; |
| |
| if (processing_template_decl && DECL_HIDDEN_FRIEND_P (cand->fn)) |
| /* This prevents build_new_function_call from discarding this |
| function during instantiation of the enclosing template. */ |
| KOENIG_LOOKUP_P (call) = 1; |
| |
| /* Specify evaluation order as per P0145R2. */ |
| CALL_EXPR_ORDERED_ARGS (call) = false; |
| switch (op_is_ordered (code)) |
| { |
| case -1: |
| CALL_EXPR_REVERSE_ARGS (call) = true; |
| break; |
| |
| case 1: |
| CALL_EXPR_ORDERED_ARGS (call) = true; |
| break; |
| |
| default: |
| break; |
| } |
| } |
| |
| /* If this was a C++20 rewritten comparison, adjust the result. */ |
| if (cand->rewritten ()) |
| { |
| /* FIXME build_min_non_dep_op_overload can't handle rewrites. */ |
| if (overload) |
| *overload = NULL_TREE; |
| switch (code) |
| { |
| case EQ_EXPR: |
| gcc_checking_assert (cand->reversed ()); |
| gcc_fallthrough (); |
| case NE_EXPR: |
| /* If a rewritten operator== candidate is selected by |
| overload resolution for an operator @, its return type |
| shall be cv bool.... */ |
| if (TREE_CODE (TREE_TYPE (result)) != BOOLEAN_TYPE) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| error_at (loc, "return type of %qD is not %qs", |
| cand->fn, "bool"); |
| inform (loc, "used as rewritten candidate for " |
| "comparison of %qT and %qT", |
| arg1_type, arg2_type); |
| } |
| result = error_mark_node; |
| } |
| else if (code == NE_EXPR) |
| /* !(y == x) or !(x == y) */ |
| result = build1_loc (loc, TRUTH_NOT_EXPR, |
| boolean_type_node, result); |
| break; |
| |
| /* If a rewritten operator<=> candidate is selected by |
| overload resolution for an operator @, x @ y is |
| interpreted as 0 @ (y <=> x) if the selected candidate is |
| a synthesized candidate with reversed order of parameters, |
| or (x <=> y) @ 0 otherwise, using the selected rewritten |
| operator<=> candidate. */ |
| case SPACESHIP_EXPR: |
| if (!cand->reversed ()) |
| /* We're in the build_new_op call below for an outer |
| reversed call; we don't need to do anything more. */ |
| break; |
| gcc_fallthrough (); |
| case LT_EXPR: |
| case LE_EXPR: |
| case GT_EXPR: |
| case GE_EXPR: |
| { |
| tree lhs = result; |
| tree rhs = integer_zero_node; |
| if (cand->reversed ()) |
| std::swap (lhs, rhs); |
| warning_sentinel ws (warn_zero_as_null_pointer_constant); |
| result = build_new_op (loc, code, |
| LOOKUP_NORMAL|LOOKUP_REWRITTEN, |
| lhs, rhs, NULL_TREE, |
| NULL, complain); |
| } |
| break; |
| |
| default: |
| gcc_unreachable (); |
| } |
| } |
| } |
| else |
| { |
| /* Give any warnings we noticed during overload resolution. */ |
| if (cand->warnings && (complain & tf_warning)) |
| { |
| struct candidate_warning *w; |
| for (w = cand->warnings; w; w = w->next) |
| joust (cand, w->loser, 1, complain); |
| } |
| |
| /* Check for comparison of different enum types. */ |
| switch (code) |
| { |
| case GT_EXPR: |
| case LT_EXPR: |
| case GE_EXPR: |
| case LE_EXPR: |
| case EQ_EXPR: |
| case NE_EXPR: |
| if (TREE_CODE (arg1_type) == ENUMERAL_TYPE |
| && TREE_CODE (arg2_type) == ENUMERAL_TYPE |
| && (TYPE_MAIN_VARIANT (arg1_type) |
| != TYPE_MAIN_VARIANT (arg2_type)) |
| && (complain & tf_warning)) |
| warning_at (loc, OPT_Wenum_compare, |
| "comparison between %q#T and %q#T", |
| arg1_type, arg2_type); |
| break; |
| default: |
| break; |
| } |
| |
| /* "If a built-in candidate is selected by overload resolution, the |
| operands of class type are converted to the types of the |
| corresponding parameters of the selected operation function, |
| except that the second standard conversion sequence of a |
| user-defined conversion sequence (12.3.3.1.2) is not applied." */ |
| conv = cand->convs[0]; |
| if (conv->user_conv_p) |
| { |
| conv = strip_standard_conversion (conv); |
| arg1 = convert_like (conv, arg1, complain); |
| } |
| |
| if (arg2) |
| { |
| conv = cand->convs[1]; |
| if (conv->user_conv_p) |
| { |
| conv = strip_standard_conversion (conv); |
| arg2 = convert_like (conv, arg2, complain); |
| } |
| } |
| |
| if (arg3) |
| { |
| conv = cand->convs[2]; |
| if (conv->user_conv_p) |
| { |
| conv = strip_standard_conversion (conv); |
| arg3 = convert_like (conv, arg3, complain); |
| } |
| } |
| } |
| } |
| |
| user_defined_result_ready: |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| if (result || result_valid_p) |
| return result; |
| |
| builtin: |
| switch (code) |
| { |
| case MODIFY_EXPR: |
| return cp_build_modify_expr (loc, arg1, code2, arg2, complain); |
| |
| case INDIRECT_REF: |
| return cp_build_indirect_ref (loc, arg1, RO_UNARY_STAR, complain); |
| |
| case TRUTH_ANDIF_EXPR: |
| case TRUTH_ORIF_EXPR: |
| case TRUTH_AND_EXPR: |
| case TRUTH_OR_EXPR: |
| if (complain & tf_warning) |
| warn_logical_operator (loc, code, boolean_type_node, |
| code_orig_arg1, arg1, |
| code_orig_arg2, arg2); |
| /* Fall through. */ |
| case GT_EXPR: |
| case LT_EXPR: |
| case GE_EXPR: |
| case LE_EXPR: |
| case EQ_EXPR: |
| case NE_EXPR: |
| if ((complain & tf_warning) |
| && ((code_orig_arg1 == BOOLEAN_TYPE) |
| ^ (code_orig_arg2 == BOOLEAN_TYPE))) |
| maybe_warn_bool_compare (loc, code, arg1, arg2); |
| if (complain & tf_warning && warn_tautological_compare) |
| warn_tautological_cmp (loc, code, arg1, arg2); |
| /* Fall through. */ |
| case SPACESHIP_EXPR: |
| case PLUS_EXPR: |
| case MINUS_EXPR: |
| case MULT_EXPR: |
| case TRUNC_DIV_EXPR: |
| case MAX_EXPR: |
| case MIN_EXPR: |
| case LSHIFT_EXPR: |
| case RSHIFT_EXPR: |
| case TRUNC_MOD_EXPR: |
| case BIT_AND_EXPR: |
| case BIT_IOR_EXPR: |
| case BIT_XOR_EXPR: |
| return cp_build_binary_op (loc, code, arg1, arg2, complain); |
| |
| case UNARY_PLUS_EXPR: |
| case NEGATE_EXPR: |
| case BIT_NOT_EXPR: |
| case TRUTH_NOT_EXPR: |
| case PREINCREMENT_EXPR: |
| case POSTINCREMENT_EXPR: |
| case PREDECREMENT_EXPR: |
| case POSTDECREMENT_EXPR: |
| case REALPART_EXPR: |
| case IMAGPART_EXPR: |
| case ABS_EXPR: |
| case CO_AWAIT_EXPR: |
| return cp_build_unary_op (code, arg1, false, complain); |
| |
| case ARRAY_REF: |
| return cp_build_array_ref (input_location, arg1, arg2, complain); |
| |
| case MEMBER_REF: |
| return build_m_component_ref (cp_build_indirect_ref (loc, arg1, |
| RO_ARROW_STAR, |
| complain), |
| arg2, complain); |
| |
| /* The caller will deal with these. */ |
| case ADDR_EXPR: |
| case COMPONENT_REF: |
| case COMPOUND_EXPR: |
| return NULL_TREE; |
| |
| default: |
| gcc_unreachable (); |
| } |
| return NULL_TREE; |
| } |
| |
| /* Wrapper for above. */ |
| |
| tree |
| build_new_op (const op_location_t &loc, enum tree_code code, int flags, |
| tree arg1, tree arg2, tree arg3, |
| tree *overload, tsubst_flags_t complain) |
| { |
| tree ret; |
| bool subtime = timevar_cond_start (TV_OVERLOAD); |
| ret = build_new_op_1 (loc, code, flags, arg1, arg2, arg3, |
| overload, complain); |
| timevar_cond_stop (TV_OVERLOAD, subtime); |
| return ret; |
| } |
| |
| /* CALL was returned by some call-building function; extract the actual |
| CALL_EXPR from any bits that have been tacked on, e.g. by |
| convert_from_reference. */ |
| |
| tree |
| extract_call_expr (tree call) |
| { |
| while (TREE_CODE (call) == COMPOUND_EXPR) |
| call = TREE_OPERAND (call, 1); |
| if (REFERENCE_REF_P (call)) |
| call = TREE_OPERAND (call, 0); |
| if (TREE_CODE (call) == TARGET_EXPR) |
| call = TARGET_EXPR_INITIAL (call); |
| if (cxx_dialect >= cxx2a) |
| switch (TREE_CODE (call)) |
| { |
| /* C++20 rewritten comparison operators. */ |
| case TRUTH_NOT_EXPR: |
| call = TREE_OPERAND (call, 0); |
| break; |
| case LT_EXPR: |
| case LE_EXPR: |
| case GT_EXPR: |
| case GE_EXPR: |
| case SPACESHIP_EXPR: |
| { |
| tree op0 = TREE_OPERAND (call, 0); |
| if (integer_zerop (op0)) |
| call = TREE_OPERAND (call, 1); |
| else |
| call = op0; |
| } |
| break; |
| default:; |
| } |
| |
| gcc_assert (TREE_CODE (call) == CALL_EXPR |
| || TREE_CODE (call) == AGGR_INIT_EXPR |
| || call == error_mark_node); |
| return call; |
| } |
| |
| /* Returns true if FN has two parameters, of which the second has type |
| size_t. */ |
| |
| static bool |
| second_parm_is_size_t (tree fn) |
| { |
| tree t = FUNCTION_ARG_CHAIN (fn); |
| if (!t || !same_type_p (TREE_VALUE (t), size_type_node)) |
| return false; |
| t = TREE_CHAIN (t); |
| if (t == void_list_node) |
| return true; |
| return false; |
| } |
| |
| /* True if T, an allocation function, has std::align_val_t as its second |
| argument. */ |
| |
| bool |
| aligned_allocation_fn_p (tree t) |
| { |
| if (!aligned_new_threshold) |
| return false; |
| |
| tree a = FUNCTION_ARG_CHAIN (t); |
| return (a && same_type_p (TREE_VALUE (a), align_type_node)); |
| } |
| |
| /* True if T is std::destroying_delete_t. */ |
| |
| static bool |
| std_destroying_delete_t_p (tree t) |
| { |
| return (TYPE_CONTEXT (t) == std_node |
| && id_equal (TYPE_IDENTIFIER (t), "destroying_delete_t")); |
| } |
| |
| /* A deallocation function with at least two parameters whose second parameter |
| type is of type std::destroying_delete_t is a destroying operator delete. A |
| destroying operator delete shall be a class member function named operator |
| delete. [ Note: Array deletion cannot use a destroying operator |
| delete. --end note ] */ |
| |
| tree |
| destroying_delete_p (tree t) |
| { |
| tree a = TYPE_ARG_TYPES (TREE_TYPE (t)); |
| if (!a || !TREE_CHAIN (a)) |
| return NULL_TREE; |
| tree type = TREE_VALUE (TREE_CHAIN (a)); |
| return std_destroying_delete_t_p (type) ? type : NULL_TREE; |
| } |
| |
| struct dealloc_info |
| { |
| bool sized; |
| bool aligned; |
| tree destroying; |
| }; |
| |
| /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation |
| function (3.7.4.2 [basic.stc.dynamic.deallocation]). If so, and DI is |
| non-null, also set *DI. */ |
| |
| static bool |
| usual_deallocation_fn_p (tree t, dealloc_info *di) |
| { |
| if (di) *di = dealloc_info(); |
| |
| /* A template instance is never a usual deallocation function, |
| regardless of its signature. */ |
| if (TREE_CODE (t) == TEMPLATE_DECL |
| || primary_template_specialization_p (t)) |
| return false; |
| |
| /* A usual deallocation function is a deallocation function whose parameters |
| after the first are |
| - optionally, a parameter of type std::destroying_delete_t, then |
| - optionally, a parameter of type std::size_t, then |
| - optionally, a parameter of type std::align_val_t. */ |
| bool global = DECL_NAMESPACE_SCOPE_P (t); |
| tree chain = FUNCTION_ARG_CHAIN (t); |
| if (chain && destroying_delete_p (t)) |
| { |
| if (di) di->destroying = TREE_VALUE (chain); |
| chain = TREE_CHAIN (chain); |
| } |
| if (chain |
| && (!global || flag_sized_deallocation) |
| && same_type_p (TREE_VALUE (chain), size_type_node)) |
| { |
| if (di) di->sized = true; |
| chain = TREE_CHAIN (chain); |
| } |
| if (chain && aligned_new_threshold |
| && same_type_p (TREE_VALUE (chain), align_type_node)) |
| { |
| if (di) di->aligned = true; |
| chain = TREE_CHAIN (chain); |
| } |
| return (chain == void_list_node); |
| } |
| |
| /* Just return whether FN is a usual deallocation function. */ |
| |
| bool |
| usual_deallocation_fn_p (tree fn) |
| { |
| return usual_deallocation_fn_p (fn, NULL); |
| } |
| |
| /* Build a call to operator delete. This has to be handled very specially, |
| because the restrictions on what signatures match are different from all |
| other call instances. For a normal delete, only a delete taking (void *) |
| or (void *, size_t) is accepted. For a placement delete, only an exact |
| match with the placement new is accepted. |
| |
| CODE is either DELETE_EXPR or VEC_DELETE_EXPR. |
| ADDR is the pointer to be deleted. |
| SIZE is the size of the memory block to be deleted. |
| GLOBAL_P is true if the delete-expression should not consider |
| class-specific delete operators. |
| PLACEMENT is the corresponding placement new call, or NULL_TREE. |
| |
| If this call to "operator delete" is being generated as part to |
| deallocate memory allocated via a new-expression (as per [expr.new] |
| which requires that if the initialization throws an exception then |
| we call a deallocation function), then ALLOC_FN is the allocation |
| function. */ |
| |
| tree |
| build_op_delete_call (enum tree_code code, tree addr, tree size, |
| bool global_p, tree placement, |
| tree alloc_fn, tsubst_flags_t complain) |
| { |
| tree fn = NULL_TREE; |
| tree fns, fnname, type, t; |
| dealloc_info di_fn = { }; |
| |
| if (addr == error_mark_node) |
| return error_mark_node; |
| |
| type = strip_array_types (TREE_TYPE (TREE_TYPE (addr))); |
| |
| fnname = ovl_op_identifier (false, code); |
| |
| if (CLASS_TYPE_P (type) |
| && COMPLETE_TYPE_P (complete_type (type)) |
| && !global_p) |
| /* In [class.free] |
| |
| If the result of the lookup is ambiguous or inaccessible, or if |
| the lookup selects a placement deallocation function, the |
| program is ill-formed. |
| |
| Therefore, we ask lookup_fnfields to complain about ambiguity. */ |
| { |
| fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1); |
| if (fns == error_mark_node) |
| return error_mark_node; |
| } |
| else |
| fns = NULL_TREE; |
| |
| if (fns == NULL_TREE) |
| fns = lookup_name_nonclass (fnname); |
| |
| /* Strip const and volatile from addr. */ |
| tree oaddr = addr; |
| addr = cp_convert (ptr_type_node, addr, complain); |
| |
| if (placement) |
| { |
| /* "A declaration of a placement deallocation function matches the |
| declaration of a placement allocation function if it has the same |
| number of parameters and, after parameter transformations (8.3.5), |
| all parameter types except the first are identical." |
| |
| So we build up the function type we want and ask instantiate_type |
| to get it for us. */ |
| t = FUNCTION_ARG_CHAIN (alloc_fn); |
| t = tree_cons (NULL_TREE, ptr_type_node, t); |
| t = build_function_type (void_type_node, t); |
| |
| fn = instantiate_type (t, fns, tf_none); |
| if (fn == error_mark_node) |
| return NULL_TREE; |
| |
| fn = MAYBE_BASELINK_FUNCTIONS (fn); |
| |
| /* "If the lookup finds the two-parameter form of a usual deallocation |
| function (3.7.4.2) and that function, considered as a placement |
| deallocation function, would have been selected as a match for the |
| allocation function, the program is ill-formed." */ |
| if (second_parm_is_size_t (fn)) |
| { |
| const char *const msg1 |
| = G_("exception cleanup for this placement new selects " |
| "non-placement %<operator delete%>"); |
| const char *const msg2 |
| = G_("%qD is a usual (non-placement) deallocation " |
| "function in C++14 (or with %<-fsized-deallocation%>)"); |
| |
| /* But if the class has an operator delete (void *), then that is |
| the usual deallocation function, so we shouldn't complain |
| about using the operator delete (void *, size_t). */ |
| if (DECL_CLASS_SCOPE_P (fn)) |
| for (lkp_iterator iter (MAYBE_BASELINK_FUNCTIONS (fns)); |
| iter; ++iter) |
| { |
| tree elt = *iter; |
| if (usual_deallocation_fn_p (elt) |
| && FUNCTION_ARG_CHAIN (elt) == void_list_node) |
| goto ok; |
| } |
| /* Before C++14 a two-parameter global deallocation function is |
| always a placement deallocation function, but warn if |
| -Wc++14-compat. */ |
| else if (!flag_sized_deallocation) |
| { |
| if (complain & tf_warning) |
| { |
| auto_diagnostic_group d; |
| if (warning (OPT_Wc__14_compat, msg1)) |
| inform (DECL_SOURCE_LOCATION (fn), msg2, fn); |
| } |
| goto ok; |
| } |
| |
| if (complain & tf_warning_or_error) |
| { |
| auto_diagnostic_group d; |
| if (permerror (input_location, msg1)) |
| { |
| /* Only mention C++14 for namespace-scope delete. */ |
| if (DECL_NAMESPACE_SCOPE_P (fn)) |
| inform (DECL_SOURCE_LOCATION (fn), msg2, fn); |
| else |
| inform (DECL_SOURCE_LOCATION (fn), |
| "%qD is a usual (non-placement) deallocation " |
| "function", fn); |
| } |
| } |
| else |
| return error_mark_node; |
| ok:; |
| } |
| } |
| else |
| /* "Any non-placement deallocation function matches a non-placement |
| allocation function. If the lookup finds a single matching |
| deallocation function, that function will be called; otherwise, no |
| deallocation function will be called." */ |
| for (lkp_iterator iter (MAYBE_BASELINK_FUNCTIONS (fns)); iter; ++iter) |
| { |
| tree elt = *iter; |
| dealloc_info di_elt; |
| if (usual_deallocation_fn_p (elt, &di_elt)) |
| { |
| if (!fn) |
| { |
| fn = elt; |
| di_fn = di_elt; |
| continue; |
| } |
| |
| /* -- If any of the deallocation functions is a destroying |
| operator delete, all deallocation functions that are not |
| destroying operator deletes are eliminated from further |
| consideration. */ |
| if (di_elt.destroying != di_fn.destroying) |
| { |
| if (di_elt.destroying) |
| { |
| fn = elt; |
| di_fn = di_elt; |
| } |
| continue; |
| } |
| |
| /* -- If the type has new-extended alignment, a function with a |
| parameter of type std::align_val_t is preferred; otherwise a |
| function without such a parameter is preferred. If exactly one |
| preferred function is found, that function is selected and the |
| selection process terminates. If more than one preferred |
| function is found, all non-preferred functions are eliminated |
| from further consideration. */ |
| if (aligned_new_threshold) |
| { |
| bool want_align = type_has_new_extended_alignment (type); |
| if (di_elt.aligned != di_fn.aligned) |
| { |
| if (want_align == di_elt.aligned) |
| { |
| fn = elt; |
| di_fn = di_elt; |
| } |
| continue; |
| } |
| } |
| |
| /* -- If the deallocation functions have class scope, the one |
| without a parameter of type std::size_t is selected. */ |
| bool want_size; |
| if (DECL_CLASS_SCOPE_P (fn)) |
| want_size = false; |
| |
| /* -- If the type is complete and if, for the second alternative |
| (delete array) only, the operand is a pointer to a class type |
| with a non-trivial destructor or a (possibly multi-dimensional) |
| array thereof, the function with a parameter of type std::size_t |
| is selected. |
| |
| -- Otherwise, it is unspecified whether a deallocation function |
| with a parameter of type std::size_t is selected. */ |
| else |
| { |
| want_size = COMPLETE_TYPE_P (type); |
| if (code == VEC_DELETE_EXPR |
| && !TYPE_VEC_NEW_USES_COOKIE (type)) |
| /* We need a cookie to determine the array size. */ |
| want_size = false; |
| } |
| gcc_assert (di_fn.sized != di_elt.sized); |
| if (want_size == di_elt.sized) |
| { |
| fn = elt; |
| di_fn = di_elt; |
| } |
| } |
| } |
| |
| /* If we have a matching function, call it. */ |
| if (fn) |
| { |
| gcc_assert (TREE_CODE (fn) == FUNCTION_DECL); |
| |
| /* If the FN is a member function, make sure that it is |
| accessible. */ |
| if (BASELINK_P (fns)) |
| perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn, |
| complain); |
| |
| /* Core issue 901: It's ok to new a type with deleted delete. */ |
| if (DECL_DELETED_FN (fn) && alloc_fn) |
| return NULL_TREE; |
| |
| if (placement) |
| { |
| /* The placement args might not be suitable for overload |
| resolution at this point, so build the call directly. */ |
| int nargs = call_expr_nargs (placement); |
| tree *argarray = XALLOCAVEC (tree, nargs); |
| int i; |
| argarray[0] = addr; |
| for (i = 1; i < nargs; i++) |
| argarray[i] = CALL_EXPR_ARG (placement, i); |
| if (!mark_used (fn, complain) && !(complain & tf_error)) |
| return error_mark_node; |
| return build_cxx_call (fn, nargs, argarray, complain); |
| } |
| else |
| { |
| tree destroying = di_fn.destroying; |
| if (destroying) |
| { |
| /* Strip const and volatile from addr but retain the type of the |
| object. */ |
| tree rtype = TREE_TYPE (TREE_TYPE (oaddr)); |
| rtype = cv_unqualified (rtype); |
| rtype = TYPE_POINTER_TO (rtype); |
| addr = cp_convert (rtype, oaddr, complain); |
| destroying = build_functional_cast (input_location, |
| destroying, NULL_TREE, |
| complain); |
| } |
| |
| tree ret; |
| releasing_vec args; |
| args->quick_push (addr); |
| if (destroying) |
| args->quick_push (destroying); |
| if (di_fn.sized) |
| args->quick_push (size); |
| if (di_fn.aligned) |
| { |
| tree al = build_int_cst (align_type_node, TYPE_ALIGN_UNIT (type)); |
| args->quick_push (al); |
| } |
| ret = cp_build_function_call_vec (fn, &args, complain); |
| return ret; |
| } |
| } |
| |
| /* [expr.new] |
| |
| If no unambiguous matching deallocation function can be found, |
| propagating the exception does not cause the object's memory to |
| be freed. */ |
| if (alloc_fn) |
| { |
| if ((complain & tf_warning) |
| && !placement) |
| warning (0, "no corresponding deallocation function for %qD", |
| alloc_fn); |
| return NULL_TREE; |
| } |
| |
| if (complain & tf_error) |
| error ("no suitable %<operator %s%> for %qT", |
| OVL_OP_INFO (false, code)->name, type); |
| return error_mark_node; |
| } |
| |
| /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL |
| in the diagnostics. |
| |
| If ISSUE_ERROR is true, then issue an error about the |
| access, followed by a note showing the declaration. |
| Otherwise, just show the note. */ |
| |
| void |
| complain_about_access (tree decl, tree diag_decl, bool issue_error) |
| { |
| if (TREE_PRIVATE (decl)) |
| { |
| if (issue_error) |
| error ("%q#D is private within this context", diag_decl); |
| inform (DECL_SOURCE_LOCATION (diag_decl), |
| "declared private here"); |
| } |
| else if (TREE_PROTECTED (decl)) |
| { |
| if (issue_error) |
| error ("%q#D is protected within this context", diag_decl); |
| inform (DECL_SOURCE_LOCATION (diag_decl), |
| "declared protected here"); |
| } |
| else |
| { |
| if (issue_error) |
| error ("%q#D is inaccessible within this context", diag_decl); |
| inform (DECL_SOURCE_LOCATION (diag_decl), "declared here"); |
| } |
| } |
| |
| /* If the current scope isn't allowed to access DECL along |
| BASETYPE_PATH, give an error. The most derived class in |
| BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is |
| the declaration to use in the error diagnostic. */ |
| |
| bool |
| enforce_access (tree basetype_path, tree decl, tree diag_decl, |
| tsubst_flags_t complain, access_failure_info *afi) |
| { |
| gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO); |
| |
| if (flag_new_inheriting_ctors |
| && DECL_INHERITED_CTOR (decl)) |
| { |
| /* 7.3.3/18: The additional constructors are accessible if they would be |
| accessible when used to construct an object of the corresponding base |
| class. */ |
| decl = strip_inheriting_ctors (decl); |
| basetype_path = lookup_base (basetype_path, DECL_CONTEXT (decl), |
| ba_any, NULL, complain); |
| } |
| |
| if (!accessible_p (basetype_path, decl, true)) |
| { |
| if (flag_new_inheriting_ctors) |
| diag_decl = strip_inheriting_ctors (diag_decl); |
| if (complain & tf_error) |
| complain_about_access (decl, diag_decl, true); |
| if (afi) |
| afi->record_access_failure (basetype_path, decl, diag_decl); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a |
| bitwise or of LOOKUP_* values. If any errors are warnings are |
| generated, set *DIAGNOSTIC_FN to "error" or "warning", |
| respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN |
| to NULL. */ |
| |
| static tree |
| build_temp (tree expr, tree type, int flags, |
| diagnostic_t *diagnostic_kind, tsubst_flags_t complain) |
| { |
| int savew, savee; |
| |
| *diagnostic_kind = DK_UNSPECIFIED; |
| |
| /* If the source is a packed field, calling the copy constructor will require |
| binding the field to the reference parameter to the copy constructor, and |
| we'll end up with an infinite loop. If we can use a bitwise copy, then |
| do that now. */ |
| if ((lvalue_kind (expr) & clk_packed) |
| && CLASS_TYPE_P (TREE_TYPE (expr)) |
| && !type_has_nontrivial_copy_init (TREE_TYPE (expr))) |
| return get_target_expr_sfinae (expr, complain); |
| |
| /* In decltype, we might have decided not to wrap this call in a TARGET_EXPR. |
| But it turns out to be a subexpression, so perform temporary |
| materialization now. */ |
| if (TREE_CODE (expr) == CALL_EXPR |
| && CLASS_TYPE_P (type) |
| && same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr))) |
| expr = build_cplus_new (type, expr, complain); |
| |
| savew = warningcount + werrorcount, savee = errorcount; |
| releasing_vec args (make_tree_vector_single (expr)); |
| expr = build_special_member_call (NULL_TREE, complete_ctor_identifier, |
| &args, type, flags, complain); |
| if (warningcount + werrorcount > savew) |
| *diagnostic_kind = DK_WARNING; |
| else if (errorcount > savee) |
| *diagnostic_kind = DK_ERROR; |
| return expr; |
| } |
| |
| /* Get any location for EXPR, falling back to input_location. |
| |
| If the result is in a system header and is the virtual location for |
| a token coming from the expansion of a macro, unwind it to the |
| location of the expansion point of the macro (e.g. to avoid the |
| diagnostic being suppressed for expansions of NULL where "NULL" is |
| in a system header). */ |
| |
| static location_t |
| get_location_for_expr_unwinding_for_system_header (tree expr) |
| { |
| location_t loc = EXPR_LOC_OR_LOC (expr, input_location); |
| loc = expansion_point_location_if_in_system_header (loc); |
| return loc; |
| } |
| |
| /* Perform warnings about peculiar, but valid, conversions from/to NULL. |
| Also handle a subset of zero as null warnings. |
| EXPR is implicitly converted to type TOTYPE. |
| FN and ARGNUM are used for diagnostics. */ |
| |
| static void |
| conversion_null_warnings (tree totype, tree expr, tree fn, int argnum) |
| { |
| /* Issue warnings about peculiar, but valid, uses of NULL. */ |
| if (TREE_CODE (totype) != BOOLEAN_TYPE |
| && ARITHMETIC_TYPE_P (totype) |
| && null_node_p (expr)) |
| { |
| location_t loc = get_location_for_expr_unwinding_for_system_header (expr); |
| if (fn) |
| { |
| auto_diagnostic_group d; |
| if (warning_at (loc, OPT_Wconversion_null, |
| "passing NULL to non-pointer argument %P of %qD", |
| argnum, fn)) |
| inform (get_fndecl_argument_location (fn, argnum), |
| " declared here"); |
| } |
| else |
| warning_at (loc, OPT_Wconversion_null, |
| "converting to non-pointer type %qT from NULL", totype); |
| } |
| |
| /* Issue warnings if "false" is converted to a NULL pointer */ |
| else if (TREE_CODE (TREE_TYPE (expr)) == BOOLEAN_TYPE |
| && TYPE_PTR_P (totype)) |
| { |
| location_t loc = get_location_for_expr_unwinding_for_system_header (expr); |
| if (fn) |
| { |
| auto_diagnostic_group d; |
| if (warning_at (loc, OPT_Wconversion_null, |
| "converting %<false%> to pointer type for argument " |
| "%P of %qD", argnum, fn)) |
| inform (get_fndecl_argument_location (fn, argnum), |
| " declared here"); |
| } |
| else |
| warning_at (loc, OPT_Wconversion_null, |
| "converting %<false%> to pointer type %qT", totype); |
| } |
| /* Handle zero as null pointer warnings for cases other |
| than EQ_EXPR and NE_EXPR */ |
| else if ((TYPE_PTR_OR_PTRMEM_P (totype) || NULLPTR_TYPE_P (totype)) |
| && null_ptr_cst_p (expr)) |
| { |
| location_t loc = get_location_for_expr_unwinding_for_system_header (expr); |
| maybe_warn_zero_as_null_pointer_constant (expr, loc); |
| } |
| } |
| |
| /* We gave a diagnostic during a conversion. If this was in the second |
| standard conversion sequence of a user-defined conversion sequence, say |
| which user-defined conversion. */ |
| |
| static void |
| maybe_print_user_conv_context (conversion *convs) |
| { |
| if (convs->user_conv_p) |
| for (conversion *t = convs; t; t = next_conversion (t)) |
| if (t->kind == ck_user) |
| { |
| print_z_candidate (0, N_(" after user-defined conversion:"), |
| t->cand); |
| break; |
| } |
| } |
| |
| /* Locate the parameter with the given index within FNDECL. |
| ARGNUM is zero based, -1 indicates the `this' argument of a method. |
| Return the location of the FNDECL itself if there are problems. */ |
| |
| location_t |
| get_fndecl_argument_location (tree fndecl, int argnum) |
| { |
| /* The locations of implicitly-declared functions are likely to be |
| more meaningful than those of their parameters. */ |
| if (DECL_ARTIFICIAL (fndecl)) |
| return DECL_SOURCE_LOCATION (fndecl); |
| |
| int i; |
| tree param; |
| |
| /* Locate param by index within DECL_ARGUMENTS (fndecl). */ |
| for (i = 0, param = FUNCTION_FIRST_USER_PARM (fndecl); |
| i < argnum && param; |
| i++, param = TREE_CHAIN (param)) |
| ; |
| |
| /* If something went wrong (e.g. if we have a builtin and thus no arguments), |
| return the location of FNDECL. */ |
| if (param == NULL) |
| return DECL_SOURCE_LOCATION (fndecl); |
| |
| return DECL_SOURCE_LOCATION (param); |
| } |
| |
| /* If FNDECL is non-NULL, issue a note highlighting ARGNUM |
| within its declaration (or the fndecl itself if something went |
| wrong). */ |
| |
| void |
| maybe_inform_about_fndecl_for_bogus_argument_init (tree fn, int argnum) |
| { |
| if (fn) |
| inform (get_fndecl_argument_location (fn, argnum), |
| " initializing argument %P of %qD", argnum, fn); |
| } |
| |
| /* Maybe warn about C++20 Conversions to arrays of unknown bound. C is |
| the conversion, EXPR is the expression we're converting. */ |
| |
| static void |
| maybe_warn_array_conv (location_t loc, conversion *c, tree expr) |
| { |
| if (cxx_dialect >= cxx2a) |
| return; |
| |
| tree type = TREE_TYPE (expr); |
| type = strip_pointer_operator (type); |
| |
| if (TREE_CODE (type) != ARRAY_TYPE |
| || TYPE_DOMAIN (type) == NULL_TREE) |
| return; |
| |
| if (conv_binds_to_array_of_unknown_bound (c)) |
| pedwarn (loc, OPT_Wpedantic, "conversions to arrays of unknown bound " |
| "are only available with %<-std=c++2a%> or %<-std=gnu++2a%>"); |
| } |
| |
| /* Return true if converting FROM to TO is unsafe in a template. */ |
| |
| static bool |
| conv_unsafe_in_template_p (tree to, tree from) |
| { |
| /* Converting classes involves TARGET_EXPR. */ |
| if (CLASS_TYPE_P (to) || CLASS_TYPE_P (from)) |
| return true; |
| |
| /* Converting real to integer produces FIX_TRUNC_EXPR which tsubst |
| doesn't handle. */ |
| if (SCALAR_FLOAT_TYPE_P (from) && INTEGRAL_OR_ENUMERATION_TYPE_P (to)) |
| return true; |
| |
| /* Converting integer to real isn't a trivial conversion, either. */ |
| if (INTEGRAL_OR_ENUMERATION_TYPE_P (from) && SCALAR_FLOAT_TYPE_P (to)) |
| return true; |
| |
| return false; |
| } |
| |
| /* Wrapper for convert_like_real_1 that handles creating IMPLICIT_CONV_EXPR. */ |
| |
| static tree |
| convert_like_real (conversion *convs, tree expr, tree fn, int argnum, |
| bool issue_conversion_warnings, |
| bool c_cast_p, tsubst_flags_t complain) |
| { |
| /* Creating &TARGET_EXPR<> in a template breaks when substituting, |
| and creating a CALL_EXPR in a template breaks in finish_call_expr |
| so use an IMPLICIT_CONV_EXPR for this conversion. We would have |
| created such codes e.g. when calling a user-defined conversion |
| function. */ |
| tree conv_expr = NULL_TREE; |
| if (processing_template_decl |
| && convs->kind != ck_identity |
| && conv_unsafe_in_template_p (convs->type, TREE_TYPE (expr))) |
| { |
| conv_expr = build1 (IMPLICIT_CONV_EXPR, convs->type, expr); |
| if (convs->kind != ck_ref_bind) |
| conv_expr = convert_from_reference (conv_expr); |
| if (!convs->bad_p) |
| return conv_expr; |
| /* Do the normal processing to give the bad_p errors. But we still |
| need to return the IMPLICIT_CONV_EXPR, unless we're returning |
| error_mark_node. */ |
| } |
| expr = convert_like_real_1 (convs, expr, fn, argnum, |
| issue_conversion_warnings, c_cast_p, complain); |
| if (expr == error_mark_node) |
| return error_mark_node; |
| return conv_expr ? conv_expr : expr; |
| } |
| |
| /* Perform the conversions in CONVS on the expression EXPR. FN and |
| ARGNUM are used for diagnostics. ARGNUM is zero based, -1 |
| indicates the `this' argument of a method. INNER is nonzero when |
| being called to continue a conversion chain. It is negative when a |
| reference binding will be applied, positive otherwise. If |
| ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious |
| conversions will be emitted if appropriate. If C_CAST_P is true, |
| this conversion is coming from a C-style cast; in that case, |
| conversions to inaccessible bases are permitted. */ |
| |
| static tree |
| convert_like_real_1 (conversion *convs, tree expr, tree fn, int argnum, |
| bool issue_conversion_warnings, |
| bool c_cast_p, tsubst_flags_t complain) |
| { |
| tree totype = convs->type; |
| diagnostic_t diag_kind; |
| int flags; |
| location_t loc = cp_expr_loc_or_input_loc (expr); |
| |
| if (convs->bad_p && !(complain & tf_error)) |
| return error_mark_node; |
| |
| if (convs->bad_p |
| && convs->kind != ck_user |
| && convs->kind != ck_list |
| && convs->kind != ck_ambig |
| && (convs->kind != ck_ref_bind |
| || (convs->user_conv_p && next_conversion (convs)->bad_p)) |
| && (convs->kind != ck_rvalue |
| || SCALAR_TYPE_P (totype)) |
| && convs->kind != ck_base) |
| { |
| bool complained = false; |
| conversion *t = convs; |
| |
| /* Give a helpful error if this is bad because of excess braces. */ |
| if (BRACE_ENCLOSED_INITIALIZER_P (expr) |
| && SCALAR_TYPE_P (totype) |
| && CONSTRUCTOR_NELTS (expr) > 0 |
| && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value)) |
| { |
| complained = permerror (loc, "too many braces around initializer " |
| "for %qT", totype); |
| while (BRACE_ENCLOSED_INITIALIZER_P (expr) |
| && CONSTRUCTOR_NELTS (expr) == 1) |
| expr = CONSTRUCTOR_ELT (expr, 0)->value; |
| } |
| |
| /* Give a helpful error if this is bad because a conversion to bool |
| from std::nullptr_t requires direct-initialization. */ |
| if (NULLPTR_TYPE_P (TREE_TYPE (expr)) |
| && TREE_CODE (totype) == BOOLEAN_TYPE) |
| complained = permerror (loc, "converting to %qH from %qI requires " |
| "direct-initialization", |
| totype, TREE_TYPE (expr)); |
| |
| for (; t ; t = next_conversion (t)) |
| { |
| if (t->kind == ck_user && t->cand->reason) |
| { |
| auto_diagnostic_group d; |
| complained = permerror (loc, "invalid user-defined conversion " |
| "from %qH to %qI", TREE_TYPE (expr), |
| totype); |
| if (complained) |
| print_z_candidate (loc, N_("candidate is:"), t->cand); |
| expr = convert_like_real (t, expr, fn, argnum, |
| /*issue_conversion_warnings=*/false, |
| /*c_cast_p=*/false, |
| complain); |
| if (convs->kind == ck_ref_bind) |
| expr = convert_to_reference (totype, expr, CONV_IMPLICIT, |
| LOOKUP_NORMAL, NULL_TREE, |
| complain); |
| else |
| expr = cp_convert (totype, expr, complain); |
| if (complained) |
| maybe_inform_about_fndecl_for_bogus_argument_init (fn, argnum); |
| return expr; |
| } |
| else if (t->kind == ck_user || !t->bad_p) |
| { |
| expr = convert_like_real (t, expr, fn, argnum, |
| /*issue_conversion_warnings=*/false, |
| /*c_cast_p=*/false, |
| complain); |
| break; |
| } |
| else if (t->kind == ck_ambig) |
| return convert_like_real (t, expr, fn, argnum, |
| /*issue_conversion_warnings=*/false, |
| /*c_cast_p=*/false, |
| complain); |
| else if (t->kind == ck_identity) |
| break; |
| } |
| if (!complained) |
| { |
| range_label_for_type_mismatch label (TREE_TYPE (expr), totype); |
| gcc_rich_location richloc (loc, &label); |
| complained = permerror (&richloc, |
| "invalid conversion from %qH to %qI", |
| TREE_TYPE (expr), totype); |
| } |
| if (complained) |
| maybe_inform_about_fndecl_for_bogus_argument_init (fn, argnum); |
| |
| return cp_convert (totype, expr, complain); |
| } |
| |
| if (issue_conversion_warnings && (complain & tf_warning)) |
| conversion_null_warnings (totype, expr, fn, argnum); |
| |
| switch (convs->kind) |
| { |
| case ck_user: |
| { |
| struct z_candidate *cand = convs->cand; |
| |
| if (cand == NULL) |
| /* We chose the surrogate function from add_conv_candidate, now we |
| actually need to build the conversion. */ |
| cand = build_user_type_conversion_1 (totype, expr, |
| LOOKUP_NO_CONVERSION, complain); |
| |
| tree convfn = cand->fn; |
| |
| /* When converting from an init list we consider explicit |
| constructors, but actually trying to call one is an error. */ |
| if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn) |
| && BRACE_ENCLOSED_INITIALIZER_P (expr) |
| /* Unless this is for direct-list-initialization. */ |
| && (!CONSTRUCTOR_IS_DIRECT_INIT (expr) || convs->need_temporary_p) |
| /* And in C++98 a default constructor can't be explicit. */ |
| && cxx_dialect >= cxx11) |
| { |
| if (!(complain & tf_error)) |
| return error_mark_node; |
| location_t loc = location_of (expr); |
| if (CONSTRUCTOR_NELTS (expr) == 0 |
| && FUNCTION_FIRST_USER_PARMTYPE (convfn) != void_list_node) |
| { |
| auto_diagnostic_group d; |
| if (pedwarn (loc, 0, "converting to %qT from initializer list " |
| "would use explicit constructor %qD", |
| totype, convfn)) |
| inform (loc, "in C++11 and above a default constructor " |
| "can be explicit"); |
| } |
| else |
| error ("converting to %qT from initializer list would use " |
| "explicit constructor %qD", totype, convfn); |
| } |
| |
| /* If we're initializing from {}, it's value-initialization. */ |
| if (BRACE_ENCLOSED_INITIALIZER_P (expr) |
| && CONSTRUCTOR_NELTS (expr) == 0 |
| && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype) |
| && !processing_template_decl) |
| { |
| bool direct = CONSTRUCTOR_IS_DIRECT_INIT (expr); |
| if (abstract_virtuals_error_sfinae (NULL_TREE, totype, complain)) |
| return error_mark_node; |
| expr = build_value_init (totype, complain); |
| expr = get_target_expr_sfinae (expr, complain); |
| if (expr != error_mark_node) |
| { |
| TARGET_EXPR_LIST_INIT_P (expr) = true; |
| TARGET_EXPR_DIRECT_INIT_P (expr) = direct; |
| } |
| return expr; |
| } |
| |
| /* We don't know here whether EXPR is being used as an lvalue or |
| rvalue, but we know it's read. */ |
| mark_exp_read (expr); |
| |
| /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow |
| any more UDCs. */ |
| expr = build_over_call (cand, LOOKUP_NORMAL|LOOKUP_NO_CONVERSION, |
| complain); |
| |
| /* If this is a constructor or a function returning an aggr type, |
| we need to build up a TARGET_EXPR. */ |
| if (DECL_CONSTRUCTOR_P (convfn)) |
| { |
| expr = build_cplus_new (totype, expr, complain); |
| |
| /* Remember that this was list-initialization. */ |
| if (convs->check_narrowing && expr != error_mark_node) |
| TARGET_EXPR_LIST_INIT_P (expr) = true; |
| } |
| |
| return expr; |
| } |
| case ck_identity: |
| if (BRACE_ENCLOSED_INITIALIZER_P (expr)) |
| { |
| int nelts = CONSTRUCTOR_NELTS (expr); |
| if (nelts == 0) |
| expr = build_value_init (totype, complain); |
| else if (nelts == 1) |
| expr = CONSTRUCTOR_ELT (expr, 0)->value; |
| else |
| gcc_unreachable (); |
| } |
| expr = mark_use (expr, /*rvalue_p=*/!convs->rvaluedness_matches_p, |
| /*read_p=*/true, UNKNOWN_LOCATION, |
| /*reject_builtin=*/true); |
| |
| if (type_unknown_p (expr)) |
| expr = instantiate_type (totype, expr, complain); |
| if (expr == null_node |
| && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype)) |
| /* If __null has been converted to an integer type, we do not want to |
| continue to warn about uses of EXPR as an integer, rather than as a |
| pointer. */ |
| expr = build_int_cst (totype, 0); |
| return expr; |
| case ck_ambig: |
| /* We leave bad_p off ck_ambig because overload resolution considers |
| it valid, it just fails when we try to perform it. So we need to |
| check complain here, too. */ |
| if (complain & tf_error) |
| { |
| /* Call build_user_type_conversion again for the error. */ |
| int flags = (convs->need_temporary_p |
| ? LOOKUP_IMPLICIT : LOOKUP_NORMAL); |
| build_user_type_conversion (totype, convs->u.expr, flags, complain); |
| gcc_assert (seen_error ()); |
| maybe_inform_about_fndecl_for_bogus_argument_init (fn, argnum); |
| } |
| return error_mark_node; |
| |
| case ck_list: |
| { |
| /* Conversion to std::initializer_list<T>. */ |
| tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0); |
| unsigned len = CONSTRUCTOR_NELTS (expr); |
| tree array; |
| |
| if (len) |
| { |
| tree val; unsigned ix; |
| |
| tree new_ctor = build_constructor (init_list_type_node, NULL); |
| |
| /* Convert all the elements. */ |
| FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val) |
| { |
| tree sub = convert_like_real (convs->u.list[ix], val, fn, |
| argnum, false, false, complain); |
| if (sub == error_mark_node) |
| return sub; |
| if (!BRACE_ENCLOSED_INITIALIZER_P (val) |
| && !check_narrowing (TREE_TYPE (sub), val, complain)) |
| return error_mark_node; |
| CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), |
| NULL_TREE, sub); |
| if (!TREE_CONSTANT (sub)) |
| TREE_CONSTANT (new_ctor) = false; |
| } |
| /* Build up the array. */ |
| elttype = cp_build_qualified_type |
| (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST); |
| array = build_array_of_n_type (elttype, len); |
| array = finish_compound_literal (array, new_ctor, complain); |
| /* Take the address explicitly rather than via decay_conversion |
| to avoid the error about taking the address of a temporary. */ |
| array = cp_build_addr_expr (array, complain); |
| } |
| else |
| array = nullptr_node; |
| |
| array = cp_convert (build_pointer_type (elttype), array, complain); |
| if (array == error_mark_node) |
| return error_mark_node; |
| |
| /* Build up the initializer_list object. Note: fail gracefully |
| if the object cannot be completed because, for example, no |
| definition is provided (c++/80956). */ |
| totype = complete_type_or_maybe_complain (totype, NULL_TREE, complain); |
| if (!totype) |
| return error_mark_node; |
| tree field = next_initializable_field (TYPE_FIELDS (totype)); |
| vec<constructor_elt, va_gc> *vec = NULL; |
| CONSTRUCTOR_APPEND_ELT (vec, field, array); |
| field = next_initializable_field (DECL_CHAIN (field)); |
| CONSTRUCTOR_APPEND_ELT (vec, field, size_int (len)); |
| tree new_ctor = build_constructor (totype, vec); |
| return get_target_expr_sfinae (new_ctor, complain); |
| } |
| |
| case ck_aggr: |
| if (TREE_CODE (totype) == COMPLEX_TYPE) |
| { |
| tree real = CONSTRUCTOR_ELT (expr, 0)->value; |
| tree imag = CONSTRUCTOR_ELT (expr, 1)->value; |
| real = perform_implicit_conversion (TREE_TYPE (totype), |
| real, complain); |
| imag = perform_implicit_conversion (TREE_TYPE (totype), |
| imag, complain); |
| expr = build2 (COMPLEX_EXPR, totype, real, imag); |
| return expr; |
| } |
| expr = reshape_init (totype, expr, complain); |
| expr = get_target_expr_sfinae (digest_init (totype, expr, complain), |
| complain); |
| if (expr != error_mark_node) |
| TARGET_EXPR_LIST_INIT_P (expr) = true; |
| return expr; |
| |
| default: |
| break; |
| }; |
| |
| expr = convert_like_real (next_conversion (convs), expr, fn, argnum, |
| convs->kind == ck_ref_bind |
| ? issue_conversion_warnings : false, |
| c_cast_p, complain & ~tf_no_cleanup); |
| if (expr == error_mark_node) |
| return error_mark_node; |
| |
| switch (convs->kind) |
| { |
| case ck_rvalue: |
| expr = decay_conversion (expr, complain); |
| if (expr == error_mark_node) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| maybe_print_user_conv_context (convs); |
| maybe_inform_about_fndecl_for_bogus_argument_init (fn, argnum); |
| } |
| return error_mark_node; |
| } |
| |
| if (! MAYBE_CLASS_TYPE_P (totype)) |
| return expr; |
| |
| /* Don't introduce copies when passing arguments along to the inherited |
| constructor. */ |
| if (current_function_decl |
| && flag_new_inheriting_ctors |
| && DECL_INHERITED_CTOR (current_function_decl)) |
| return expr; |
| |
| if (TREE_CODE (expr) == TARGET_EXPR |
| && TARGET_EXPR_LIST_INIT_P (expr)) |
| /* Copy-list-initialization doesn't actually involve a copy. */ |
| return expr; |
| |
| /* Fall through. */ |
| case ck_base: |
| if (convs->kind == ck_base && !convs->need_temporary_p) |
| { |
| /* We are going to bind a reference directly to a base-class |
| subobject of EXPR. */ |
| /* Build an expression for `*((base*) &expr)'. */ |
| expr = convert_to_base (expr, totype, |
| !c_cast_p, /*nonnull=*/true, complain); |
| return expr; |
| } |
| |
| /* Copy-initialization where the cv-unqualified version of the source |
| type is the same class as, or a derived class of, the class of the |
| destination [is treated as direct-initialization]. [dcl.init] */ |
| flags = LOOKUP_NORMAL; |
| /* This conversion is being done in the context of a user-defined |
| conversion (i.e. the second step of copy-initialization), so |
| don't allow any more. */ |
| if (convs->user_conv_p) |
| flags |= LOOKUP_NO_CONVERSION; |
| /* We might be performing a conversion of the argument |
| to the user-defined conversion, i.e., not a conversion of the |
| result of the user-defined conversion. In which case we skip |
| explicit constructors. */ |
| if (convs->copy_init_p) |
| flags |= LOOKUP_ONLYCONVERTING; |
| if (convs->rvaluedness_matches_p) |
| /* standard_conversion got LOOKUP_PREFER_RVALUE. */ |
| flags |= LOOKUP_PREFER_RVALUE; |
| expr = build_temp (expr, totype, flags, &diag_kind, complain); |
| if (diag_kind && complain) |
| { |
| auto_diagnostic_group d; |
| maybe_print_user_conv_context (convs); |
| maybe_inform_about_fndecl_for_bogus_argument_init (fn, argnum); |
| } |
| |
| return build_cplus_new (totype, expr, complain); |
| |
| case ck_ref_bind: |
| { |
| tree ref_type = totype; |
| |
| /* direct_reference_binding might have inserted a ck_qual under |
| this ck_ref_bind for the benefit of conversion sequence ranking. |
| Ignore the conversion; we'll create our own below. */ |
| if (next_conversion (convs)->kind == ck_qual |
| && !convs->need_temporary_p) |
| { |
| gcc_assert (same_type_p (TREE_TYPE (expr), |
| next_conversion (convs)->type)); |
| /* Strip the cast created by the ck_qual; cp_build_addr_expr |
| below expects an lvalue. */ |
| STRIP_NOPS (expr); |
| } |
| |
| if (convs->bad_p && !next_conversion (convs)->bad_p) |
| { |
| tree extype = TREE_TYPE (expr); |
| auto_diagnostic_group d; |
| if (TYPE_REF_IS_RVALUE (ref_type) |
| && lvalue_p (expr)) |
| error_at (loc, "cannot bind rvalue reference of type %qH to " |
| "lvalue of type %qI", totype, extype); |
| else if (!TYPE_REF_IS_RVALUE (ref_type) && !lvalue_p (expr) |
| && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))) |
| error_at (loc, "cannot bind non-const lvalue reference of " |
| "type %qH to an rvalue of type %qI", totype, extype); |
| else if (!reference_compatible_p (TREE_TYPE (totype), extype)) |
| { |
| /* If we're converting from T[] to T[N], don't talk |
| about discarding qualifiers. (Converting from T[N] to |
| T[] is allowed by P0388R4.) */ |
| if (TREE_CODE (extype) == ARRAY_TYPE |
| && TYPE_DOMAIN (extype) == NULL_TREE |
| && TREE_CODE (TREE_TYPE (totype)) == ARRAY_TYPE |
| && TYPE_DOMAIN (TREE_TYPE (totype)) != NULL_TREE) |
| error_at (loc, "cannot bind reference of type %qH to %qI " |
| "due to different array bounds", totype, extype); |
| else |
| error_at (loc, "binding reference of type %qH to %qI " |
| "discards qualifiers", totype, extype); |
| } |
| else |
| gcc_unreachable (); |
| maybe_print_user_conv_context (convs); |
| maybe_inform_about_fndecl_for_bogus_argument_init (fn, argnum); |
| |
| return error_mark_node; |
| } |
| else if (complain & tf_warning) |
| maybe_warn_array_conv (loc, convs, expr); |
| |
| /* If necessary, create a temporary. |
| |
| VA_ARG_EXPR and CONSTRUCTOR expressions are special cases |
| that need temporaries, even when their types are reference |
| compatible with the type of reference being bound, so the |
| upcoming call to cp_build_addr_expr doesn't fail. */ |
| if (convs->need_temporary_p |
| || TREE_CODE (expr) == CONSTRUCTOR |
| || TREE_CODE (expr) == VA_ARG_EXPR) |
| { |
| /* Otherwise, a temporary of type "cv1 T1" is created and |
| initialized from the initializer expression using the rules |
| for a non-reference copy-initialization (8.5). */ |
| |
| tree type = TREE_TYPE (ref_type); |
| cp_lvalue_kind lvalue = lvalue_kind (expr); |
| |
| gcc_assert (similar_type_p (type, next_conversion (convs)->type)); |
| if (!CP_TYPE_CONST_NON_VOLATILE_P (type) |
| && !TYPE_REF_IS_RVALUE (ref_type)) |
| { |
| /* If the reference is volatile or non-const, we |
| cannot create a temporary. */ |
| if (complain & tf_error) |
| { |
| if (lvalue & clk_bitfield) |
| error_at (loc, "cannot bind bit-field %qE to %qT", |
| expr, ref_type); |
| else if (lvalue & clk_packed) |
| error_at (loc, "cannot bind packed field %qE to %qT", |
| expr, ref_type); |
| else |
| error_at (loc, "cannot bind rvalue %qE to %qT", |
| expr, ref_type); |
| } |
| return error_mark_node; |
| } |
| /* If the source is a packed field, and we must use a copy |
| constructor, then building the target expr will require |
| binding the field to the reference parameter to the |
| copy constructor, and we'll end up with an infinite |
| loop. If we can use a bitwise copy, then we'll be |
| OK. */ |
| if ((lvalue & clk_packed) |
| && CLASS_TYPE_P (type) |
| && type_has_nontrivial_copy_init (type)) |
| { |
| error_at (loc, "cannot bind packed field %qE to %qT", |
| expr, ref_type); |
| return error_mark_node; |
| } |
| if (lvalue & clk_bitfield) |
| { |
| expr = convert_bitfield_to_declared_type (expr); |
| expr = fold_convert (type, expr); |
| } |
| |
| /* Creating &TARGET_EXPR<> in a template would break when |
| tsubsting the expression, so use an IMPLICIT_CONV_EXPR |
| instead. This can happen even when there's no class |
| involved, e.g., when converting an integer to a reference |
| type. */ |
| if (processing_template_decl) |
| return build1 (IMPLICIT_CONV_EXPR, totype, expr); |
| expr = build_target_expr_with_type (expr, type, complain); |
| } |
| |
| /* Take the address of the thing to which we will bind the |
| reference. */ |
| expr = cp_build_addr_expr (expr, complain); |
| if (expr == error_mark_node) |
| return error_mark_node; |
| |
| /* Convert it to a pointer to the type referred to by the |
| reference. This will adjust the pointer if a derived to |
| base conversion is being performed. */ |
| expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)), |
| expr, complain); |
| /* Convert the pointer to the desired reference type. */ |
| return build_nop (ref_type, expr); |
| } |
| |
| case ck_lvalue: |
| return decay_conversion (expr, complain); |
| |
| case ck_fnptr: |
| /* ??? Should the address of a transaction-safe pointer point to the TM |
| clone, and this conversion look up the primary function? */ |
| return build_nop (totype, expr); |
| |
| case ck_qual: |
| /* Warn about deprecated conversion if appropriate. */ |
| if (complain & tf_warning) |
| { |
| string_conv_p (totype, expr, 1); |
| maybe_warn_array_conv (loc, convs, expr); |
| } |
| break; |
| |
| case ck_ptr: |
| if (convs->base_p) |
| expr = convert_to_base (expr, totype, !c_cast_p, |
| /*nonnull=*/false, complain); |
| return build_nop (totype, expr); |
| |
| case ck_pmem: |
| return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false, |
| c_cast_p, complain); |
| |
| default: |
| break; |
| } |
| |
| if (convs->check_narrowing |
| && !check_narrowing (totype, expr, complain, |
| convs->check_narrowing_const_only)) |
| return error_mark_node; |
| |
| warning_sentinel w (warn_zero_as_null_pointer_constant); |
| if (issue_conversion_warnings) |
| expr = cp_convert_and_check (totype, expr, complain); |
| else |
| expr = cp_convert (totype, expr, complain); |
| |
| return expr; |
| } |
| |
| /* ARG is being passed to a varargs function. Perform any conversions |
| required. Return the converted value. */ |
| |
| tree |
| convert_arg_to_ellipsis (tree arg, tsubst_flags_t complain) |
| { |
| tree arg_type = TREE_TYPE (arg); |
| location_t loc = cp_expr_loc_or_input_loc (arg); |
| |
| /* [expr.call] |
| |
| If the argument has integral or enumeration type that is subject |
| to the integral promotions (_conv.prom_), or a floating-point |
| type that is subject to the floating-point promotion |
| (_conv.fpprom_), the value of the argument is converted to the |
| promoted type before the call. */ |
| if (TREE_CODE (arg_type) == REAL_TYPE |
| && (TYPE_PRECISION (arg_type) |
| < TYPE_PRECISION (double_type_node)) |
| && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type))) |
| { |
| if ((complain & tf_warning) |
| && warn_double_promotion && !c_inhibit_evaluation_warnings) |
| warning_at (loc, OPT_Wdouble_promotion, |
| "implicit conversion from %qH to %qI when passing " |
| "argument to function", |
| arg_type, double_type_node); |
| arg = mark_rvalue_use (arg); |
| arg = convert_to_real_nofold (double_type_node, arg); |
| } |
| else if (NULLPTR_TYPE_P (arg_type)) |
| { |
| arg = mark_rvalue_use (arg); |
| if (TREE_SIDE_EFFECTS (arg)) |
| { |
| warning_sentinel w(warn_unused_result); |
| arg = cp_build_compound_expr (arg, null_pointer_node, complain); |
| } |
| else |
| arg = null_pointer_node; |
| } |
| else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type)) |
| { |
| if (SCOPED_ENUM_P (arg_type)) |
| { |
| tree prom = cp_convert (ENUM_UNDERLYING_TYPE (arg_type), arg, |
| complain); |
| prom = cp_perform_integral_promotions (prom, complain); |
| if (abi_version_crosses (6) |
| && TYPE_MODE (TREE_TYPE (prom)) != TYPE_MODE (arg_type) |
| && (complain & tf_warning)) |
| warning_at (loc, OPT_Wabi, "scoped enum %qT passed through %<...%>" |
| " as %qT before %<-fabi-version=6%>, %qT after", |
| arg_type, |
| TREE_TYPE (prom), ENUM_UNDERLYING_TYPE (arg_type)); |
| if (!abi_version_at_least (6)) |
| arg = prom; |
| } |
| else |
| arg = cp_perform_integral_promotions (arg, complain); |
| } |
| else |
| /* [expr.call] |
| |
| The lvalue-to-rvalue, array-to-pointer, and function-to-pointer |
| standard conversions are performed. */ |
| arg = decay_conversion (arg, complain); |
| |
| arg = require_complete_type_sfinae (arg, complain); |
| arg_type = TREE_TYPE (arg); |
| |
| if (arg != error_mark_node |
| /* In a template (or ill-formed code), we can have an incomplete type |
| even after require_complete_type_sfinae, in which case we don't know |
| whether it has trivial copy or not. */ |
| && COMPLETE_TYPE_P (arg_type) |
| && !cp_unevaluated_operand) |
| { |
| /* [expr.call] 5.2.2/7: |
| Passing a potentially-evaluated argument of class type (Clause 9) |
| with a non-trivial copy constructor or a non-trivial destructor |
| with no corresponding parameter is conditionally-supported, with |
| implementation-defined semantics. |
| |
| We support it as pass-by-invisible-reference, just like a normal |
| value parameter. |
| |
| If the call appears in the context of a sizeof expression, |
| it is not potentially-evaluated. */ |
| if (type_has_nontrivial_copy_init (arg_type) |
| || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)) |
| { |
| arg = force_rvalue (arg, complain); |
| if (complain & tf_warning) |
| warning (OPT_Wconditionally_supported, |
| "passing objects of non-trivially-copyable " |
| "type %q#T through %<...%> is conditionally supported", |
| arg_type); |
| return build1 (ADDR_EXPR, build_reference_type (arg_type), arg); |
| } |
| /* Build up a real lvalue-to-rvalue conversion in case the |
| copy constructor is trivial but not callable. */ |
| else if (CLASS_TYPE_P (arg_type)) |
| force_rvalue (arg, complain); |
| |
| } |
| |
| return arg; |
| } |
| |
| /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */ |
| |
| tree |
| build_x_va_arg (location_t loc, tree expr, tree type) |
| { |
| if (processing_template_decl) |
| { |
| tree r = build_min (VA_ARG_EXPR, type, expr); |
| SET_EXPR_LOCATION (r, loc); |
| return r; |
| } |
| |
| type = complete_type_or_else (type, NULL_TREE); |
| |
| if (expr == error_mark_node || !type) |
| return error_mark_node; |
| |
| expr = mark_lvalue_use (expr); |
| |
| if (TYPE_REF_P (type)) |
| { |
| error ("cannot receive reference type %qT through %<...%>", type); |
| return error_mark_node; |
| } |
| |
| if (type_has_nontrivial_copy_init (type) |
| || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)) |
| { |
| /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat |
| it as pass by invisible reference. */ |
| warning_at (loc, OPT_Wconditionally_supported, |
| "receiving objects of non-trivially-copyable type %q#T " |
| "through %<...%> is conditionally-supported", type); |
| |
| tree ref = cp_build_reference_type (type, false); |
| expr = build_va_arg (loc, expr, ref); |
| return convert_from_reference (expr); |
| } |
| |
| tree ret = build_va_arg (loc, expr, type); |
| if (CLASS_TYPE_P (type)) |
| /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to |
| know how to handle it. */ |
| ret = get_target_expr (ret); |
| return ret; |
| } |
| |
| /* TYPE has been given to va_arg. Apply the default conversions which |
| would have happened when passed via ellipsis. Return the promoted |
| type, or the passed type if there is no change. */ |
| |
| tree |
| cxx_type_promotes_to (tree type) |
| { |
| tree promote; |
| |
| /* Perform the array-to-pointer and function-to-pointer |
| conversions. */ |
| type = type_decays_to (type); |
| |
| promote = type_promotes_to (type); |
| if (same_type_p (type, promote)) |
| promote = type; |
| |
| return promote; |
| } |
| |
| /* ARG is a default argument expression being passed to a parameter of |
| the indicated TYPE, which is a parameter to FN. PARMNUM is the |
| zero-based argument number. Do any required conversions. Return |
| the converted value. */ |
| |
| static GTY(()) vec<tree, va_gc> *default_arg_context; |
| void |
| push_defarg_context (tree fn) |
| { vec_safe_push (default_arg_context, fn); } |
| |
| void |
| pop_defarg_context (void) |
| { default_arg_context->pop (); } |
| |
| tree |
| convert_default_arg (tree type, tree arg, tree fn, int parmnum, |
| tsubst_flags_t complain) |
| { |
| int i; |
| tree t; |
| |
| /* See through clones. */ |
| fn = DECL_ORIGIN (fn); |
| /* And inheriting ctors. */ |
| if (flag_new_inheriting_ctors) |
| fn = strip_inheriting_ctors (fn); |
| |
| /* Detect recursion. */ |
| FOR_EACH_VEC_SAFE_ELT (default_arg_context, i, t) |
| if (t == fn) |
| { |
| if (complain & tf_error) |
| error ("recursive evaluation of default argument for %q#D", fn); |
| return error_mark_node; |
| } |
| |
| /* If the ARG is an unparsed default argument expression, the |
| conversion cannot be performed. */ |
| if (TREE_CODE (arg) == DEFERRED_PARSE) |
| { |
| if (complain & tf_error) |
| error ("call to %qD uses the default argument for parameter %P, which " |
| "is not yet defined", fn, parmnum); |
| return error_mark_node; |
| } |
| |
| push_defarg_context (fn); |
| |
| if (fn && DECL_TEMPLATE_INFO (fn)) |
| arg = tsubst_default_argument (fn, parmnum, type, arg, complain); |
| |
| /* Due to: |
| |
| [dcl.fct.default] |
| |
| The names in the expression are bound, and the semantic |
| constraints are checked, at the point where the default |
| expressions appears. |
| |
| we must not perform access checks here. */ |
| push_deferring_access_checks (dk_no_check); |
| /* We must make a copy of ARG, in case subsequent processing |
| alters any part of it. */ |
| arg = break_out_target_exprs (arg, /*clear location*/true); |
| |
| arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT, |
| ICR_DEFAULT_ARGUMENT, fn, parmnum, |
| complain); |
| arg = convert_for_arg_passing (type, arg, complain); |
| pop_deferring_access_checks(); |
| |
| pop_defarg_context (); |
| |
| return arg; |
| } |
| |
| /* Returns the type which will really be used for passing an argument of |
| type TYPE. */ |
| |
| tree |
| type_passed_as (tree type) |
| { |
| /* Pass classes with copy ctors by invisible reference. */ |
| if (TREE_ADDRESSABLE (type)) |
| type = build_reference_type (type); |
| else if (targetm.calls.promote_prototypes (NULL_TREE) |
| && INTEGRAL_TYPE_P (type) |
| && COMPLETE_TYPE_P (type) |
| && tree_int_cst_lt (TYPE_SIZE (type), TYPE_SIZE (integer_type_node))) |
| type = integer_type_node; |
| |
| return type; |
| } |
| |
| /* Actually perform the appropriate conversion. */ |
| |
| tree |
| convert_for_arg_passing (tree type, tree val, tsubst_flags_t complain) |
| { |
| tree bitfield_type; |
| |
| /* If VAL is a bitfield, then -- since it has already been converted |
| to TYPE -- it cannot have a precision greater than TYPE. |
| |
| If it has a smaller precision, we must widen it here. For |
| example, passing "int f:3;" to a function expecting an "int" will |
| not result in any conversion before this point. |
| |
| If the precision is the same we must not risk widening. For |
| example, the COMPONENT_REF for a 32-bit "long long" bitfield will |
| often have type "int", even though the C++ type for the field is |
| "long long". If the value is being passed to a function |
| expecting an "int", then no conversions will be required. But, |
| if we call convert_bitfield_to_declared_type, the bitfield will |
| be converted to "long long". */ |
| bitfield_type = is_bitfield_expr_with_lowered_type (val); |
| if (bitfield_type |
| && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)) |
| val = convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type), val); |
| |
| if (val == error_mark_node) |
| ; |
| /* Pass classes with copy ctors by invisible reference. */ |
| else if (TREE_ADDRESSABLE (type)) |
| val = build1 (ADDR_EXPR, build_reference_type (type), val); |
| else if (targetm.calls.promote_prototypes (NULL_TREE) |
| && INTEGRAL_TYPE_P (type) |
| && COMPLETE_TYPE_P (type) |
| && tree_int_cst_lt (TYPE_SIZE (type), TYPE_SIZE (integer_type_node))) |
| val = cp_perform_integral_promotions (val, complain); |
| if (complain & tf_warning) |
| { |
| if (warn_suggest_attribute_format) |
| { |
| tree rhstype = TREE_TYPE (val); |
| const enum tree_code coder = TREE_CODE (rhstype); |
| const enum tree_code codel = TREE_CODE (type); |
| if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE) |
| && coder == codel |
| && check_missing_format_attribute (type, rhstype)) |
| warning (OPT_Wsuggest_attribute_format, |
| "argument of function call might be a candidate " |
| "for a format attribute"); |
| } |
| maybe_warn_parm_abi (type, cp_expr_loc_or_input_loc (val)); |
| } |
| |
| if (complain & tf_warning) |
| warn_for_address_or_pointer_of_packed_member (type, val); |
| |
| return val; |
| } |
| |
| /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for |
| which just decay_conversion or no conversions at all should be done. |
| This is true for some builtins which don't act like normal functions. |
| Return 2 if no conversions at all should be done, 1 if just |
| decay_conversion. Return 3 for special treatment of the 3rd argument |
| for __builtin_*_overflow_p. */ |
| |
| int |
| magic_varargs_p (tree fn) |
| { |
| if (DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL) |
| switch (DECL_FUNCTION_CODE (fn)) |
| { |
| case BUILT_IN_CLASSIFY_TYPE: |
| case BUILT_IN_CONSTANT_P: |
| case BUILT_IN_NEXT_ARG: |
| case BUILT_IN_VA_START: |
| return 1; |
| |
| case BUILT_IN_ADD_OVERFLOW_P: |
| case BUILT_IN_SUB_OVERFLOW_P: |
| case BUILT_IN_MUL_OVERFLOW_P: |
| return 3; |
| |
| default:; |
| return lookup_attribute ("type generic", |
| TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0; |
| } |
| |
| return 0; |
| } |
| |
| /* Returns the decl of the dispatcher function if FN is a function version. */ |
| |
| tree |
| get_function_version_dispatcher (tree fn) |
| { |
| tree dispatcher_decl = NULL; |
| |
| gcc_assert (TREE_CODE (fn) == FUNCTION_DECL |
| && DECL_FUNCTION_VERSIONED (fn)); |
| |
| gcc_assert (targetm.get_function_versions_dispatcher); |
| dispatcher_decl = targetm.get_function_versions_dispatcher (fn); |
| |
| if (dispatcher_decl == NULL) |
| { |
| error_at (input_location, "use of multiversioned function " |
| "without a default"); |
| return NULL; |
| } |
| |
| retrofit_lang_decl (dispatcher_decl); |
| gcc_assert (dispatcher_decl != NULL); |
| return dispatcher_decl; |
| } |
| |
| /* fn is a function version dispatcher that is marked used. Mark all the |
| semantically identical function versions it will dispatch as used. */ |
| |
| void |
| mark_versions_used (tree fn) |
| { |
| struct cgraph_node *node; |
| struct cgraph_function_version_info *node_v; |
| struct cgraph_function_version_info *it_v; |
| |
| gcc_assert (TREE_CODE (fn) == FUNCTION_DECL); |
| |
| node = cgraph_node::get (fn); |
| if (node == NULL) |
| return; |
| |
| gcc_assert (node->dispatcher_function); |
| |
| node_v = node->function_version (); |
| if (node_v == NULL) |
| return; |
| |
| /* All semantically identical versions are chained. Traverse and mark each |
| one of them as used. */ |
| it_v = node_v->next; |
| while (it_v != NULL) |
| { |
| mark_used (it_v->this_node->decl); |
| it_v = it_v->next; |
| } |
| } |
| |
| /* Build a call to "the copy constructor" for the type of A, even if it |
| wouldn't be selected by normal overload resolution. Used for |
| diagnostics. */ |
| |
| static tree |
| call_copy_ctor (tree a, tsubst_flags_t complain) |
| { |
| tree ctype = TYPE_MAIN_VARIANT (TREE_TYPE (a)); |
| tree binfo = TYPE_BINFO (ctype); |
| tree copy = get_copy_ctor (ctype, complain); |
| copy = build_baselink (binfo, binfo, copy, NULL_TREE); |
| tree ob = build_dummy_object (ctype); |
| releasing_vec args (make_tree_vector_single (a)); |
| tree r = build_new_method_call (ob, copy, &args, NULL_TREE, |
| LOOKUP_NORMAL, NULL, complain); |
| return r; |
| } |
| |
| /* Return true iff T refers to a base or potentially-overlapping field, which |
| cannot be used for return by invisible reference. We avoid doing C++17 |
| mandatory copy elision when this is true. |
| |
| This returns true even if the type of T has no tail padding that other data |
| could be allocated into, because that depends on the particular ABI. |
| unsafe_copy_elision_p, below, does consider whether there is padding. */ |
| |
| bool |
| unsafe_return_slot_p (tree t) |
| { |
| STRIP_NOPS (t); |
| if (TREE_CODE (t) == ADDR_EXPR) |
| t = TREE_OPERAND (t, 0); |
| if (TREE_CODE (t) == COMPONENT_REF) |
| t = TREE_OPERAND (t, 1); |
| if (TREE_CODE (t) != FIELD_DECL) |
| return false; |
| if (!CLASS_TYPE_P (TREE_TYPE (t))) |
| /* The middle-end will do the right thing for scalar types. */ |
| return false; |
| return (DECL_FIELD_IS_BASE (t) |
| || lookup_attribute ("no_unique_address", DECL_ATTRIBUTES (t))); |
| } |
| |
| /* We can't elide a copy from a function returning by value to a |
| potentially-overlapping subobject, as the callee might clobber tail padding. |
| Return true iff this could be that case. */ |
| |
| static bool |
| unsafe_copy_elision_p (tree target, tree exp) |
| { |
| /* Copy elision only happens with a TARGET_EXPR. */ |
| if (TREE_CODE (exp) != TARGET_EXPR) |
| return false; |
| tree type = TYPE_MAIN_VARIANT (TREE_TYPE (exp)); |
| /* It's safe to elide the copy for a class with no tail padding. */ |
| if (!is_empty_class (type) |
| && tree_int_cst_equal (TYPE_SIZE (type), CLASSTYPE_SIZE (type))) |
| return false; |
| /* It's safe to elide the copy if we aren't initializing a base object. */ |
| if (!unsafe_return_slot_p (target)) |
| return false; |
| tree init = TARGET_EXPR_INITIAL (exp); |
| /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */ |
| while (TREE_CODE (init) == COMPOUND_EXPR) |
| init = TREE_OPERAND (init, 1); |
| if (TREE_CODE (init) == COND_EXPR) |
| { |
| /* We'll end up copying from each of the arms of the COND_EXPR directly |
| into the target, so look at them. */ |
| if (tree op = TREE_OPERAND (init, 1)) |
| if (unsafe_copy_elision_p (target, op)) |
| return true; |
| return unsafe_copy_elision_p (target, TREE_OPERAND (init, 2)); |
| } |
| return (TREE_CODE (init) == AGGR_INIT_EXPR |
| && !AGGR_INIT_VIA_CTOR_P (init)); |
| } |
| |
| /* True iff C is a conversion that binds a reference to a prvalue. */ |
| |
| static bool |
| conv_binds_ref_to_prvalue (conversion *c) |
| { |
| if (c->kind != ck_ref_bind) |
| return false; |
| if (c->need_temporary_p) |
| return true; |
| |
| c = next_conversion (c); |
| |
| if (c->kind == ck_rvalue) |
| return true; |
| if (c->kind == ck_user && !TYPE_REF_P (c->type)) |
| return true; |
| if (c->kind == ck_identity && c->u.expr |
| && TREE_CODE (c->u.expr) == TARGET_EXPR) |
| return true; |
| |
| return false; |
| } |
| |
| /* Call the trivial destructor for INSTANCE, which can be either an lvalue of |
| class type or a pointer to class type. */ |
| |
| tree |
| build_trivial_dtor_call (tree instance) |
| { |
| gcc_assert (!is_dummy_object (instance)); |
| |
| if (!flag_lifetime_dse) |
| { |
| no_clobber: |
| return fold_convert (void_type_node, instance); |
| } |
| |
| if (INDIRECT_TYPE_P (TREE_TYPE (instance))) |
| { |
| if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance)))) |
| goto no_clobber; |
| instance = cp_build_fold_indirect_ref (instance); |
| } |
| |
| /* A trivial destructor should still clobber the object. */ |
| tree clobber = build_clobber (TREE_TYPE (instance)); |
| return build2 (MODIFY_EXPR, void_type_node, |
| instance, clobber); |
| } |
| |
| /* Subroutine of the various build_*_call functions. Overload resolution |
| has chosen a winning candidate CAND; build up a CALL_EXPR accordingly. |
| ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a |
| bitmask of various LOOKUP_* flags which apply to the call itself. */ |
| |
| static tree |
| build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain) |
| { |
| tree fn = cand->fn; |
| const vec<tree, va_gc> *args = cand->args; |
| tree first_arg = cand->first_arg; |
| conversion **convs = cand->convs; |
| conversion *conv; |
| tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn)); |
| int parmlen; |
| tree val; |
| int i = 0; |
| int j = 0; |
| unsigned int arg_index = 0; |
| int is_method = 0; |
| int nargs; |
| tree *argarray; |
| bool already_used = false; |
| |
| /* In a template, there is no need to perform all of the work that |
| is normally done. We are only interested in the type of the call |
| expression, i.e., the return type of the function. Any semantic |
| errors will be deferred until the template is instantiated. */ |
| if (processing_template_decl) |
| { |
| tree expr, addr; |
| tree return_type; |
| const tree *argarray; |
| unsigned int nargs; |
| |
| if (undeduced_auto_decl (fn)) |
| mark_used (fn, complain); |
| else |
| /* Otherwise set TREE_USED for the benefit of -Wunused-function. |
| See PR80598. */ |
| TREE_USED (fn) = 1; |
| |
| return_type = TREE_TYPE (TREE_TYPE (fn)); |
| nargs = vec_safe_length (args); |
| if (first_arg == NULL_TREE) |
| argarray = args->address (); |
| else |
| { |
| tree *alcarray; |
| unsigned int ix; |
| tree arg; |
| |
| ++nargs; |
| alcarray = XALLOCAVEC (tree, nargs); |
| alcarray[0] = build_this (first_arg); |
| FOR_EACH_VEC_SAFE_ELT (args, ix, arg) |
| alcarray[ix + 1] = arg; |
| argarray = alcarray; |
| } |
| |
| addr = build_addr_func (fn, complain); |
| if (addr == error_mark_node) |
| return error_mark_node; |
| expr = build_call_array_loc (input_location, return_type, |
| addr, nargs, argarray); |
| if (TREE_THIS_VOLATILE (fn) && cfun) |
| current_function_returns_abnormally = 1; |
| if (TREE_CODE (fn) == FUNCTION_DECL |
| && DECL_IMMEDIATE_FUNCTION_P (fn) |
| && cp_unevaluated_operand == 0 |
| && (current_function_decl == NULL_TREE |
| || !DECL_IMMEDIATE_FUNCTION_P (current_function_decl)) |
| && (current_binding_level->kind != sk_function_parms |
| || !current_binding_level->immediate_fn_ctx_p)) |
| { |
| tree obj_arg = NULL_TREE, exprimm = expr; |
| if (DECL_CONSTRUCTOR_P (fn)) |
| obj_arg = first_arg; |
| if (obj_arg |
| && is_dummy_object (obj_arg) |
| && !type_dependent_expression_p (obj_arg)) |
| { |
| exprimm = build_cplus_new (DECL_CONTEXT (fn), expr, complain); |
| obj_arg = NULL_TREE; |
| } |
| /* Look through *(const T *)&obj. */ |
| else if (obj_arg && TREE_CODE (obj_arg) == INDIRECT_REF) |
| { |
| tree addr = TREE_OPERAND (obj_arg, 0); |
| STRIP_NOPS (addr); |
| if (TREE_CODE (addr) == ADDR_EXPR) |
| { |
| tree typeo = TREE_TYPE (obj_arg); |
| tree typei = TREE_TYPE (TREE_OPERAND (addr, 0)); |
| if (same_type_ignoring_top_level_qualifiers_p (typeo, typei)) |
| obj_arg = TREE_OPERAND (addr, 0); |
| } |
| } |
| fold_non_dependent_expr (exprimm, complain, |
| /*manifestly_const_eval=*/true, |
| obj_arg); |
| } |
| return convert_from_reference (expr); |
| } |
| |
| /* Give any warnings we noticed during overload resolution. */ |
| if (cand->warnings && (complain & tf_warning)) |
| { |
| struct candidate_warning *w; |
| for (w = cand->warnings; w; w = w->next) |
| joust (cand, w->loser, 1, complain); |
| } |
| |
| /* Core issue 2327: P0135 doesn't say how to handle the case where the |
| argument to the copy constructor ends up being a prvalue after |
| conversion. Let's do the normal processing, but pretend we aren't |
| actually using the copy constructor. */ |
| bool force_elide = false; |
| if (cxx_dialect >= cxx17 |
| && cand->num_convs == 1 |
| && DECL_COMPLETE_CONSTRUCTOR_P (fn) |
| && (DECL_COPY_CONSTRUCTOR_P (fn) |
| || DECL_MOVE_CONSTRUCTOR_P (fn)) |
| && !unsafe_return_slot_p (first_arg) |
| && conv_binds_ref_to_prvalue (convs[0])) |
| { |
| force_elide = true; |
| goto not_really_used; |
| } |
| |
| /* OK, we're actually calling this inherited constructor; set its deletedness |
| appropriately. We can get away with doing this here because calling is |
| the only way to refer to a constructor. */ |
| if (DECL_INHERITED_CTOR (fn)) |
| deduce_inheriting_ctor (fn); |
| |
| /* Make =delete work with SFINAE. */ |
| if (DECL_DELETED_FN (fn)) |
| { |
| if (complain & tf_error) |
| mark_used (fn); |
| return error_mark_node; |
| } |
| |
| if (DECL_FUNCTION_MEMBER_P (fn)) |
| { |
| tree access_fn; |
| /* If FN is a template function, two cases must be considered. |
| For example: |
| |
| struct A { |
| protected: |
| template <class T> void f(); |
| }; |
| template <class T> struct B { |
| protected: |
| void g(); |
| }; |
| struct C : A, B<int> { |
| using A::f; // #1 |
| using B<int>::g; // #2 |
| }; |
| |
| In case #1 where `A::f' is a member template, DECL_ACCESS is |
| recorded in the primary template but not in its specialization. |
| We check access of FN using its primary template. |
| |
| In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply |
| because it is a member of class template B, DECL_ACCESS is |
| recorded in the specialization `B<int>::g'. We cannot use its |
| primary template because `B<T>::g' and `B<int>::g' may have |
| different access. */ |
| if (DECL_TEMPLATE_INFO (fn) |
| && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn))) |
| access_fn = DECL_TI_TEMPLATE (fn); |
| else |
| access_fn = fn; |
| if (!perform_or_defer_access_check (cand->access_path, access_fn, |
| fn, complain)) |
| return error_mark_node; |
| } |
| |
| /* If we're checking for implicit delete, don't bother with argument |
| conversions. */ |
| if (flags & LOOKUP_SPECULATIVE) |
| { |
| if (cand->viable == 1) |
| return fn; |
| else if (!(complain & tf_error)) |
| /* Reject bad conversions now. */ |
| return error_mark_node; |
| /* else continue to get conversion error. */ |
| } |
| |
| not_really_used: |
| |
| /* N3276 magic doesn't apply to nested calls. */ |
| tsubst_flags_t decltype_flag = (complain & tf_decltype); |
| complain &= ~tf_decltype; |
| /* No-Cleanup doesn't apply to nested calls either. */ |
| tsubst_flags_t no_cleanup_complain = complain; |
| complain &= ~tf_no_cleanup; |
| |
| /* Find maximum size of vector to hold converted arguments. */ |
| parmlen = list_length (parm); |
| nargs = vec_safe_length (args) + (first_arg != NULL_TREE ? 1 : 0); |
| if (parmlen > nargs) |
| nargs = parmlen; |
| argarray = XALLOCAVEC (tree, nargs); |
| |
| /* The implicit parameters to a constructor are not considered by overload |
| resolution, and must be of the proper type. */ |
| if (DECL_CONSTRUCTOR_P (fn)) |
| { |
| tree object_arg; |
| if (first_arg != NULL_TREE) |
| { |
| object_arg = first_arg; |
| first_arg = NULL_TREE; |
| } |
| else |
| { |
| object_arg = (*args)[arg_index]; |
| ++arg_index; |
| } |
| argarray[j++] = build_this (object_arg); |
| parm = TREE_CHAIN (parm); |
| /* We should never try to call the abstract constructor. */ |
| gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn)); |
| |
| if (DECL_HAS_VTT_PARM_P (fn)) |
| { |
| argarray[j++] = (*args)[arg_index]; |
| ++arg_index; |
| parm = TREE_CHAIN (parm); |
| } |
| |
| if (flags & LOOKUP_PREFER_RVALUE) |
| { |
| /* The implicit move specified in 15.8.3/3 fails "...if the type of |
| the first parameter of the selected constructor is not an rvalue |
| reference to the object's type (possibly cv-qualified)...." */ |
| gcc_assert (!(complain & tf_error)); |
| tree ptype = convs[0]->type; |
| if (!TYPE_REF_P (ptype) |
| || !TYPE_REF_IS_RVALUE (ptype) |
| || CONVERSION_RANK (convs[0]) > cr_exact) |
| return error_mark_node; |
| } |
| } |
| /* Bypass access control for 'this' parameter. */ |
| else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE) |
| { |
| tree parmtype = TREE_VALUE (parm); |
| tree arg = build_this (first_arg != NULL_TREE |
| ? first_arg |
| : (*args)[arg_index]); |
| tree argtype = TREE_TYPE (arg); |
| tree converted_arg; |
| tree base_binfo; |
| |
| if (arg == error_mark_node) |
| return error_mark_node; |
| |
| if (convs[i]->bad_p) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| if (permerror (input_location, "passing %qT as %<this%> " |
| "argument discards qualifiers", |
| TREE_TYPE (argtype))) |
| inform (DECL_SOURCE_LOCATION (fn), " in call to %qD", fn); |
| } |
| else |
| return error_mark_node; |
| } |
| |
| /* See if the function member or the whole class type is declared |
| final and the call can be devirtualized. */ |
| if (DECL_FINAL_P (fn) |
| || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn)))) |
| flags |= LOOKUP_NONVIRTUAL; |
| |
| /* [class.mfct.nonstatic]: If a nonstatic member function of a class |
| X is called for an object that is not of type X, or of a type |
| derived from X, the behavior is undefined. |
| |
| So we can assume that anything passed as 'this' is non-null, and |
| optimize accordingly. */ |
| gcc_assert (TYPE_PTR_P (parmtype)); |
| /* Convert to the base in which the function was declared. */ |
| gcc_assert (cand->conversion_path != NULL_TREE); |
| /* Check that the base class is accessible. */ |
| if (!accessible_base_p (TREE_TYPE (argtype), |
| BINFO_TYPE (cand->conversion_path), true)) |
| { |
| if (complain & tf_error) |
| error ("%qT is not an accessible base of %qT", |
| BINFO_TYPE (cand->conversion_path), |
| TREE_TYPE (argtype)); |
| else |
| return error_mark_node; |
| } |
| /* If fn was found by a using declaration, the conversion path |
| will be to the derived class, not the base declaring fn. We |
| must convert from derived to base. */ |
| base_binfo = lookup_base (cand->conversion_path, |
| TREE_TYPE (parmtype), ba_unique, |
| NULL, complain); |
| |
| /* If we know the dynamic type of the object, look up the final overrider |
| in the BINFO. */ |
| if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0 |
| && resolves_to_fixed_type_p (arg)) |
| { |
| tree ov = lookup_vfn_in_binfo (DECL_VINDEX (fn), base_binfo); |
| |
| /* And unwind base_binfo to match. If we don't find the type we're |
| looking for in BINFO_INHERITANCE_CHAIN, we're looking at diamond |
| inheritance; for now do a normal virtual call in that case. */ |
| tree octx = DECL_CONTEXT (ov); |
| tree obinfo = base_binfo; |
| while (obinfo && !SAME_BINFO_TYPE_P (BINFO_TYPE (obinfo), octx)) |
| obinfo = BINFO_INHERITANCE_CHAIN (obinfo); |
| if (obinfo) |
| { |
| fn = ov; |
| base_binfo = obinfo; |
| flags |= LOOKUP_NONVIRTUAL; |
| } |
| } |
| |
| converted_arg = build_base_path (PLUS_EXPR, arg, |
| base_binfo, 1, complain); |
| |
| argarray[j++] = converted_arg; |
| parm = TREE_CHAIN (parm); |
| if (first_arg != NULL_TREE) |
| first_arg = NULL_TREE; |
| else |
| ++arg_index; |
| ++i; |
| is_method = 1; |
| } |
| |
| gcc_assert (first_arg == NULL_TREE); |
| for (; arg_index < vec_safe_length (args) && parm; |
| parm = TREE_CHAIN (parm), ++arg_index, ++i) |
| { |
| tree type = TREE_VALUE (parm); |
| tree arg = (*args)[arg_index]; |
| bool conversion_warning = true; |
| |
| conv = convs[i]; |
| |
| /* If the argument is NULL and used to (implicitly) instantiate a |
| template function (and bind one of the template arguments to |
| the type of 'long int'), we don't want to warn about passing NULL |
| to non-pointer argument. |
| For example, if we have this template function: |
| |
| template<typename T> void func(T x) {} |
| |
| we want to warn (when -Wconversion is enabled) in this case: |
| |
| void foo() { |
| func<int>(NULL); |
| } |
| |
| but not in this case: |
| |
| void foo() { |
| func(NULL); |
| } |
| */ |
| if (null_node_p (arg) |
| && DECL_TEMPLATE_INFO (fn) |
| && cand->template_decl |
| && !(flags & LOOKUP_EXPLICIT_TMPL_ARGS)) |
| conversion_warning = false; |
| |
| /* Set user_conv_p on the argument conversions, so rvalue/base handling |
| knows not to allow any more UDCs. This needs to happen after we |
| process cand->warnings. */ |
| if (flags & LOOKUP_NO_CONVERSION) |
| conv->user_conv_p = true; |
| |
| tsubst_flags_t arg_complain = complain; |
| if (!conversion_warning) |
| arg_complain &= ~tf_warning; |
| |
| val = convert_like_with_context (conv, arg, fn, i - is_method, |
| arg_complain); |
| val = convert_for_arg_passing (type, val, arg_complain); |
| |
| if (val == error_mark_node) |
| return error_mark_node; |
| else |
| argarray[j++] = val; |
| } |
| |
| /* Default arguments */ |
| for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++) |
| { |
| if (TREE_VALUE (parm) == error_mark_node) |
| return error_mark_node; |
| val = convert_default_arg (TREE_VALUE (parm), |
| TREE_PURPOSE (parm), |
| fn, i - is_method, |
| complain); |
| if (val == error_mark_node) |
| return error_mark_node; |
| argarray[j++] = val; |
| } |
| |
| /* Ellipsis */ |
| int magic = magic_varargs_p (fn); |
| for (; arg_index < vec_safe_length (args); ++arg_index) |
| { |
| tree a = (*args)[arg_index]; |
| if ((magic == 3 && arg_index == 2) || magic == 2) |
| { |
| /* Do no conversions for certain magic varargs. */ |
| a = mark_type_use (a); |
| if (TREE_CODE (a) == FUNCTION_DECL && reject_gcc_builtin (a)) |
| return error_mark_node; |
| } |
| else if (magic != 0) |
| /* For other magic varargs only do decay_conversion. */ |
| a = decay_conversion (a, complain); |
| else if (DECL_CONSTRUCTOR_P (fn) |
| && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn), |
| TREE_TYPE (a))) |
| { |
| /* Avoid infinite recursion trying to call A(...). */ |
| if (complain & tf_error) |
| /* Try to call the actual copy constructor for a good error. */ |
| call_copy_ctor (a, complain); |
| return error_mark_node; |
| } |
| else |
| a = convert_arg_to_ellipsis (a, complain); |
| if (a == error_mark_node) |
| return error_mark_node; |
| argarray[j++] = a; |
| } |
| |
| gcc_assert (j <= nargs); |
| nargs = j; |
| |
| /* Avoid to do argument-transformation, if warnings for format, and for |
| nonnull are disabled. Just in case that at least one of them is active |
| the check_function_arguments function might warn about something. */ |
| |
| bool warned_p = false; |
| if (warn_nonnull |
| || warn_format |
| || warn_suggest_attribute_format |
| || warn_restrict) |
| { |
| tree *fargs = (!nargs ? argarray |
| : (tree *) alloca (nargs * sizeof (tree))); |
| for (j = 0; j < nargs; j++) |
| { |
| /* For -Wformat undo the implicit passing by hidden reference |
| done by convert_arg_to_ellipsis. */ |
| if (TREE_CODE (argarray[j]) == ADDR_EXPR |
| && TYPE_REF_P (TREE_TYPE (argarray[j]))) |
| fargs[j] = TREE_OPERAND (argarray[j], 0); |
| else |
| fargs[j] = argarray[j]; |
| } |
| |
| warned_p = check_function_arguments (input_location, fn, TREE_TYPE (fn), |
| nargs, fargs, NULL); |
| } |
| |
| if (DECL_INHERITED_CTOR (fn)) |
| { |
| /* Check for passing ellipsis arguments to an inherited constructor. We |
| could handle this by open-coding the inherited constructor rather than |
| defining it, but let's not bother now. */ |
| if (!cp_unevaluated_operand |
| && cand->num_convs |
| && cand->convs[cand->num_convs-1]->ellipsis_p) |
| { |
| if (complain & tf_error) |
| { |
| sorry ("passing arguments to ellipsis of inherited constructor " |
| "%qD", cand->fn); |
| inform (DECL_SOURCE_LOCATION (cand->fn), "declared here"); |
| } |
| return error_mark_node; |
| } |
| |
| /* A base constructor inheriting from a virtual base doesn't get the |
| inherited arguments, just this and __vtt. */ |
| if (ctor_omit_inherited_parms (fn)) |
| nargs = 2; |
| } |
| |
| /* Avoid actually calling copy constructors and copy assignment operators, |
| if possible. */ |
| |
| if (! flag_elide_constructors && !force_elide) |
| /* Do things the hard way. */; |
| else if (cand->num_convs == 1 |
| && (DECL_COPY_CONSTRUCTOR_P (fn) |
| || DECL_MOVE_CONSTRUCTOR_P (fn)) |
| /* It's unsafe to elide the constructor when handling |
| a noexcept-expression, it may evaluate to the wrong |
| value (c++/53025). */ |
| && (force_elide || cp_noexcept_operand == 0)) |
| { |
| tree targ; |
| tree arg = argarray[num_artificial_parms_for (fn)]; |
| tree fa = argarray[0]; |
| bool trivial = trivial_fn_p (fn); |
| |
| /* Pull out the real argument, disregarding const-correctness. */ |
| targ = arg; |
| /* Strip the reference binding for the constructor parameter. */ |
| if (CONVERT_EXPR_P (targ) |
| && TYPE_REF_P (TREE_TYPE (targ))) |
| targ = TREE_OPERAND (targ, 0); |
| /* But don't strip any other reference bindings; binding a temporary to a |
| reference prevents copy elision. */ |
| while ((CONVERT_EXPR_P (targ) |
| && !TYPE_REF_P (TREE_TYPE (targ))) |
| || TREE_CODE (targ) == NON_LVALUE_EXPR) |
| targ = TREE_OPERAND (targ, 0); |
| if (TREE_CODE (targ) == ADDR_EXPR) |
| { |
| targ = TREE_OPERAND (targ, 0); |
| if (!same_type_ignoring_top_level_qualifiers_p |
| (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ))) |
| targ = NULL_TREE; |
| } |
| else |
| targ = NULL_TREE; |
| |
| if (targ) |
| arg = targ; |
| else |
| arg = cp_build_fold_indirect_ref (arg); |
| |
| /* In C++17 we shouldn't be copying a TARGET_EXPR except into a |
| potentially-overlapping subobject. */ |
| if (CHECKING_P && cxx_dialect >= cxx17) |
| gcc_assert (TREE_CODE (arg) != TARGET_EXPR |
| || force_elide |
| /* It's from binding the ref parm to a packed field. */ |
| || convs[0]->need_temporary_p |
| || seen_error () |
| /* See unsafe_copy_elision_p. */ |
| || unsafe_return_slot_p (fa)); |
| |
| bool unsafe = unsafe_copy_elision_p (fa, arg); |
| bool eliding_temp = (TREE_CODE (arg) == TARGET_EXPR && !unsafe); |
| |
| /* [class.copy]: the copy constructor is implicitly defined even if the |
| implementation elided its use. But don't warn about deprecation when |
| eliding a temporary, as then no copy is actually performed. */ |
| warning_sentinel s (warn_deprecated_copy, eliding_temp); |
| if (force_elide) |
| /* The language says this isn't called. */; |
| else if (!trivial) |
| { |
| if (!mark_used (fn, complain) && !(complain & tf_error)) |
| return error_mark_node; |
| already_used = true; |
| } |
| else |
| cp_warn_deprecated_use (fn, complain); |
| |
| /* If we're creating a temp and we already have one, don't create a |
| new one. If we're not creating a temp but we get one, use |
| INIT_EXPR to collapse the temp into our target. Otherwise, if the |
| ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a |
| temp or an INIT_EXPR otherwise. */ |
| if (is_dummy_object (fa)) |
| { |
| if (TREE_CODE (arg) == TARGET_EXPR) |
| return arg; |
| else if (trivial) |
| return force_target_expr (DECL_CONTEXT (fn), arg, complain); |
| } |
| else if ((trivial || TREE_CODE (arg) == TARGET_EXPR) |
| && !unsafe) |
| { |
| tree to = cp_stabilize_reference (cp_build_fold_indirect_ref (fa)); |
| |
| val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg); |
| return val; |
| } |
| } |
| else if (DECL_ASSIGNMENT_OPERATOR_P (fn) |
| && DECL_OVERLOADED_OPERATOR_IS (fn, NOP_EXPR) |
| && trivial_fn_p (fn)) |
| { |
| /* Don't use cp_build_fold_indirect_ref, op= returns an lvalue even if |
| the object argument isn't one. */ |
| tree to = cp_build_indirect_ref (input_location, argarray[0], |
| RO_ARROW, complain); |
| to = cp_stabilize_reference (to); |
| tree type = TREE_TYPE (to); |
| tree as_base = CLASSTYPE_AS_BASE (type); |
| tree arg = argarray[1]; |
| location_t loc = cp_expr_loc_or_input_loc (arg); |
| |
| if (is_really_empty_class (type, /*ignore_vptr*/true)) |
| { |
| /* Avoid copying empty classes. */ |
| val = build2 (COMPOUND_EXPR, type, arg, to); |
| TREE_NO_WARNING (val) = 1; |
| } |
| else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base))) |
| { |
| if (is_std_init_list (type) |
| && conv_binds_ref_to_prvalue (convs[1])) |
| warning_at (loc, OPT_Winit_list_lifetime, |
| "assignment from temporary %<initializer_list%> does " |
| "not extend the lifetime of the underlying array"); |
| arg = cp_build_fold_indirect_ref (arg); |
| val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg); |
| } |
| else |
| { |
| /* We must only copy the non-tail padding parts. */ |
| tree arg0, arg2, t; |
| tree array_type, alias_set; |
| |
| arg2 = TYPE_SIZE_UNIT (as_base); |
| arg0 = cp_build_addr_expr (to, complain); |
| |
| array_type = build_array_type (unsigned_char_type_node, |
| build_index_type |
| (size_binop (MINUS_EXPR, |
| arg2, size_int (1)))); |
| alias_set = build_int_cst (build_pointer_type (type), 0); |
| t = build2 (MODIFY_EXPR, void_type_node, |
| build2 (MEM_REF, array_type, arg0, alias_set), |
| build2 (MEM_REF, array_type, arg, alias_set)); |
| val = build2 (COMPOUND_EXPR, TREE_TYPE (to), t, to); |
| TREE_NO_WARNING (val) = 1; |
| } |
| |
| cp_warn_deprecated_use (fn, complain); |
| |
| return val; |
| } |
| else if (trivial_fn_p (fn)) |
| { |
| if (DECL_DESTRUCTOR_P (fn)) |
| return build_trivial_dtor_call (argarray[0]); |
| else if (default_ctor_p (fn)) |
| { |
| if (is_dummy_object (argarray[0])) |
| return force_target_expr (DECL_CONTEXT (fn), void_node, |
| no_cleanup_complain); |
| else |
| return cp_build_fold_indirect_ref (argarray[0]); |
| } |
| } |
| |
| gcc_assert (!force_elide); |
| |
| if (!already_used |
| && !mark_used (fn, complain)) |
| return error_mark_node; |
| |
| /* Warn if the built-in writes to an object of a non-trivial type. */ |
| if (warn_class_memaccess |
| && vec_safe_length (args) >= 2 |
| && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL) |
| maybe_warn_class_memaccess (input_location, fn, args); |
| |
| if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0) |
| { |
| tree t; |
| tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])), |
| DECL_CONTEXT (fn), |
| ba_any, NULL, complain); |
| gcc_assert (binfo && binfo != error_mark_node); |
| |
| argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1, |
| complain); |
| if (TREE_SIDE_EFFECTS (argarray[0])) |
| argarray[0] = save_expr (argarray[0]); |
| t = build_pointer_type (TREE_TYPE (fn)); |
| fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn)); |
| TREE_TYPE (fn) = t; |
| } |
| else |
| { |
| /* If FN is marked deprecated, then we've already issued a deprecated-use |
| warning from mark_used above, so avoid redundantly issuing another one |
| from build_addr_func. */ |
| warning_sentinel w (warn_deprecated_decl); |
| |
| fn = build_addr_func (fn, complain); |
| if (fn == error_mark_node) |
| return error_mark_node; |
| } |
| |
| tree call = build_cxx_call (fn, nargs, argarray, complain|decltype_flag); |
| if (call == error_mark_node) |
| return call; |
| if (cand->flags & LOOKUP_LIST_INIT_CTOR) |
| { |
| tree c = extract_call_expr (call); |
| /* build_new_op_1 will clear this when appropriate. */ |
| CALL_EXPR_ORDERED_ARGS (c) = true; |
| } |
| if (warned_p) |
| { |
| tree c = extract_call_expr (call); |
| if (TREE_CODE (c) == CALL_EXPR) |
| TREE_NO_WARNING (c) = 1; |
| } |
| if (TREE_CODE (fn) == ADDR_EXPR) |
| { |
| tree fndecl = STRIP_TEMPLATE (TREE_OPERAND (fn, 0)); |
| if (TREE_CODE (fndecl) == FUNCTION_DECL |
| && DECL_IMMEDIATE_FUNCTION_P (fndecl) |
| && cp_unevaluated_operand == 0 |
| && (current_function_decl == NULL_TREE |
| || !DECL_IMMEDIATE_FUNCTION_P (current_function_decl)) |
| && (current_binding_level->kind != sk_function_parms |
| || !current_binding_level->immediate_fn_ctx_p)) |
| { |
| tree obj_arg = NULL_TREE; |
| /* Undo convert_from_reference called by build_cxx_call. */ |
| if (REFERENCE_REF_P (call)) |
| call = TREE_OPERAND (call, 0); |
| if (DECL_CONSTRUCTOR_P (fndecl)) |
| obj_arg = cand->first_arg ? cand->first_arg : (*args)[0]; |
| if (obj_arg && is_dummy_object (obj_arg)) |
| { |
| call = build_cplus_new (DECL_CONTEXT (fndecl), call, complain); |
| obj_arg = NULL_TREE; |
| } |
| /* Look through *(const T *)&obj. */ |
| else if (obj_arg && TREE_CODE (obj_arg) == INDIRECT_REF) |
| { |
| tree addr = TREE_OPERAND (obj_arg, 0); |
| STRIP_NOPS (addr); |
| if (TREE_CODE (addr) == ADDR_EXPR) |
| { |
| tree typeo = TREE_TYPE (obj_arg); |
| tree typei = TREE_TYPE (TREE_OPERAND (addr, 0)); |
| if (same_type_ignoring_top_level_qualifiers_p (typeo, typei)) |
| obj_arg = TREE_OPERAND (addr, 0); |
| } |
| } |
| call = cxx_constant_value (call, obj_arg); |
| if (obj_arg && !error_operand_p (call)) |
| call = build2 (INIT_EXPR, void_type_node, obj_arg, call); |
| call = convert_from_reference (call); |
| } |
| } |
| return call; |
| } |
| |
| namespace |
| { |
| |
| /* Return the DECL of the first non-static subobject of class TYPE |
| that satisfies the predicate PRED or null if none can be found. */ |
| |
| template <class Predicate> |
| tree |
| first_non_static_field (tree type, Predicate pred) |
| { |
| if (!type || !CLASS_TYPE_P (type)) |
| return NULL_TREE; |
| |
| for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field)) |
| { |
| if (TREE_CODE (field) != FIELD_DECL) |
| continue; |
| if (TREE_STATIC (field)) |
| continue; |
| if (pred (field)) |
| return field; |
| } |
| |
| int i = 0; |
| |
| for (tree base_binfo, binfo = TYPE_BINFO (type); |
| BINFO_BASE_ITERATE (binfo, i, base_binfo); i++) |
| { |
| tree base = TREE_TYPE (base_binfo); |
| if (pred (base)) |
| return base; |
| if (tree field = first_non_static_field (base, pred)) |
| return field; |
| } |
| |
| return NULL_TREE; |
| } |
| |
| struct NonPublicField |
| { |
| bool operator() (const_tree t) |
| { |
| return DECL_P (t) && (TREE_PRIVATE (t) || TREE_PROTECTED (t)); |
| } |
| }; |
| |
| /* Return the DECL of the first non-public subobject of class TYPE |
| or null if none can be found. */ |
| |
| static inline tree |
| first_non_public_field (tree type) |
| { |
| return first_non_static_field (type, NonPublicField ()); |
| } |
| |
| struct NonTrivialField |
| { |
| bool operator() (const_tree t) |
| { |
| return !trivial_type_p (DECL_P (t) ? TREE_TYPE (t) : t); |
| } |
| }; |
| |
| /* Return the DECL of the first non-trivial subobject of class TYPE |
| or null if none can be found. */ |
| |
| static inline tree |
| first_non_trivial_field (tree type) |
| { |
| return first_non_static_field (type, NonTrivialField ()); |
| } |
| |
| } /* unnamed namespace */ |
| |
| /* Return true if all copy and move assignment operator overloads for |
| class TYPE are trivial and at least one of them is not deleted and, |
| when ACCESS is set, accessible. Return false otherwise. Set |
| HASASSIGN to true when the TYPE has a (not necessarily trivial) |
| copy or move assignment. */ |
| |
| static bool |
| has_trivial_copy_assign_p (tree type, bool access, bool *hasassign) |
| { |
| tree fns = get_class_binding (type, assign_op_identifier); |
| bool all_trivial = true; |
| |
| /* Iterate over overloads of the assignment operator, checking |
| accessible copy assignments for triviality. */ |
| |
| for (ovl_iterator oi (fns); oi; ++oi) |
| { |
| tree f = *oi; |
| |
| /* Skip operators that aren't copy assignments. */ |
| if (!copy_fn_p (f)) |
| continue; |
| |
| bool accessible = (!access || !(TREE_PRIVATE (f) || TREE_PROTECTED (f)) |
| || accessible_p (TYPE_BINFO (type), f, true)); |
| |
| /* Skip template assignment operators and deleted functions. */ |
| if (TREE_CODE (f) != FUNCTION_DECL || DECL_DELETED_FN (f)) |
| continue; |
| |
| if (accessible) |
| *hasassign = true; |
| |
| if (!accessible || !trivial_fn_p (f)) |
| all_trivial = false; |
| |
| /* Break early when both properties have been determined. */ |
| if (*hasassign && !all_trivial) |
| break; |
| } |
| |
| /* Return true if they're all trivial and one of the expressions |
| TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */ |
| tree ref = cp_build_reference_type (type, false); |
| return (all_trivial |
| && (is_trivially_xible (MODIFY_EXPR, type, type) |
| || is_trivially_xible (MODIFY_EXPR, type, ref))); |
| } |
| |
| /* Return true if all copy and move ctor overloads for class TYPE are |
| trivial and at least one of them is not deleted and, when ACCESS is |
| set, accessible. Return false otherwise. Set each element of HASCTOR[] |
| to true when the TYPE has a (not necessarily trivial) default and copy |
| (or move) ctor, respectively. */ |
| |
| static bool |
| has_trivial_copy_p (tree type, bool access, bool hasctor[2]) |
| { |
| tree fns = get_class_binding (type, complete_ctor_identifier); |
| bool all_trivial = true; |
| |
| for (ovl_iterator oi (fns); oi; ++oi) |
| { |
| tree f = *oi; |
| |
| /* Skip template constructors. */ |
| if (TREE_CODE (f) != FUNCTION_DECL) |
| continue; |
| |
| bool cpy_or_move_ctor_p = copy_fn_p (f); |
| |
| /* Skip ctors other than default, copy, and move. */ |
| if (!cpy_or_move_ctor_p && !default_ctor_p (f)) |
| continue; |
| |
| if (DECL_DELETED_FN (f)) |
| continue; |
| |
| bool accessible = (!access || !(TREE_PRIVATE (f) || TREE_PROTECTED (f)) |
| || accessible_p (TYPE_BINFO (type), f, true)); |
| |
| if (accessible) |
| hasctor[cpy_or_move_ctor_p] = true; |
| |
| if (cpy_or_move_ctor_p && (!accessible || !trivial_fn_p (f))) |
| all_trivial = false; |
| |
| /* Break early when both properties have been determined. */ |
| if (hasctor[0] && hasctor[1] && !all_trivial) |
| break; |
| } |
| |
| return all_trivial; |
| } |
| |
| /* Issue a warning on a call to the built-in function FNDECL if it is |
| a raw memory write whose destination is not an object of (something |
| like) trivial or standard layout type with a non-deleted assignment |
| and copy ctor. Detects const correctness violations, corrupting |
| references, virtual table pointers, and bypassing non-trivial |
| assignments. */ |
| |
| static void |
| maybe_warn_class_memaccess (location_t loc, tree fndecl, |
| const vec<tree, va_gc> *args) |
| { |
| /* Except for bcopy where it's second, the destination pointer is |
| the first argument for all functions handled here. Compute |
| the index of the destination and source arguments. */ |
| unsigned dstidx = DECL_FUNCTION_CODE (fndecl) == BUILT_IN_BCOPY; |
| unsigned srcidx = !dstidx; |
| |
| tree dest = (*args)[dstidx]; |
| if (!TREE_TYPE (dest) |
| || (TREE_CODE (TREE_TYPE (dest)) != ARRAY_TYPE |
| && !INDIRECT_TYPE_P (TREE_TYPE (dest)))) |
| return; |
| |
| tree srctype = NULL_TREE; |
| |
| /* Determine the type of the pointed-to object and whether it's |
| a complete class type. */ |
| tree desttype = TREE_TYPE (TREE_TYPE (dest)); |
| |
| if (!desttype || !COMPLETE_TYPE_P (desttype) || !CLASS_TYPE_P (desttype)) |
| return; |
| |
| /* Check to see if the raw memory call is made by a non-static member |
| function with THIS as the destination argument for the destination |
| type. If so, and if the class has no non-trivial bases or members, |
| be more permissive. */ |
| if (current_function_decl |
| && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl) |
| && is_this_parameter (tree_strip_nop_conversions (dest))) |
| { |
| tree ctx = DECL_CONTEXT (current_function_decl); |
| bool special = same_type_ignoring_top_level_qualifiers_p (ctx, desttype); |
| tree binfo = TYPE_BINFO (ctx); |
| |
| if (special |
| && !BINFO_VTABLE (binfo) |
| && !first_non_trivial_field (desttype)) |
| return; |
| } |
| |
| /* True if the class is trivial. */ |
| bool trivial = trivial_type_p (desttype); |
| |
| /* Set to true if DESTYPE has an accessible copy assignment. */ |
| bool hasassign = false; |
| /* True if all of the class' overloaded copy assignment operators |
| are all trivial (and not deleted) and at least one of them is |
| accessible. */ |
| bool trivassign = has_trivial_copy_assign_p (desttype, true, &hasassign); |
| |
| /* Set to true if DESTTYPE has an accessible default and copy ctor, |
| respectively. */ |
| bool hasctors[2] = { false, false }; |
| |
| /* True if all of the class' overloaded copy constructors are all |
| trivial (and not deleted) and at least one of them is accessible. */ |
| bool trivcopy = has_trivial_copy_p (desttype, true, hasctors); |
| |
| /* Set FLD to the first private/protected member of the class. */ |
| tree fld = trivial ? first_non_public_field (desttype) : NULL_TREE; |
| |
| /* The warning format string. */ |
| const char *warnfmt = NULL; |
| /* A suggested alternative to offer instead of the raw memory call. |
| Empty string when none can be come up with. */ |
| const char *suggest = ""; |
| bool warned = false; |
| |
| switch (DECL_FUNCTION_CODE (fndecl)) |
| { |
| case BUILT_IN_MEMSET: |
| if (!integer_zerop (maybe_constant_value ((*args)[1]))) |
| { |
| /* Diagnose setting non-copy-assignable or non-trivial types, |
| or types with a private member, to (potentially) non-zero |
| bytes. Since the value of the bytes being written is unknown, |
| suggest using assignment instead (if one exists). Also warn |
| for writes into objects for which zero-initialization doesn't |
| mean all bits clear (pointer-to-member data, where null is all |
| bits set). Since the value being written is (most likely) |
| non-zero, simply suggest assignment (but not copy assignment). */ |
| suggest = "; use assignment instead"; |
| if (!trivassign) |
| warnfmt = G_("%qD writing to an object of type %#qT with " |
| "no trivial copy-assignment"); |
| else if (!trivial) |
| warnfmt = G_("%qD writing to an object of non-trivial type %#qT%s"); |
| else if (fld) |
| { |
| const char *access = TREE_PRIVATE (fld) ? "private" : "protected"; |
| warned = warning_at (loc, OPT_Wclass_memaccess, |
| "%qD writing to an object of type %#qT with " |
| "%qs member %qD", |
| fndecl, desttype, access, fld); |
| } |
| else if (!zero_init_p (desttype)) |
| warnfmt = G_("%qD writing to an object of type %#qT containing " |
| "a pointer to data member%s"); |
| |
| break; |
| } |
| /* Fall through. */ |
| |
| case BUILT_IN_BZERO: |
| /* Similarly to the above, diagnose clearing non-trivial or non- |
| standard layout objects, or objects of types with no assignmenmt. |
| Since the value being written is known to be zero, suggest either |
| copy assignment, copy ctor, or default ctor as an alternative, |
| depending on what's available. */ |
| |
| if (hasassign && hasctors[0]) |
| suggest = G_("; use assignment or value-initialization instead"); |
| else if (hasassign) |
| suggest = G_("; use assignment instead"); |
| else if (hasctors[0]) |
| suggest = G_("; use value-initialization instead"); |
| |
| if (!trivassign) |
| warnfmt = G_("%qD clearing an object of type %#qT with " |
| "no trivial copy-assignment%s"); |
| else if (!trivial) |
| warnfmt = G_("%qD clearing an object of non-trivial type %#qT%s"); |
| else if (!zero_init_p (desttype)) |
| warnfmt = G_("%qD clearing an object of type %#qT containing " |
| "a pointer-to-member%s"); |
| break; |
| |
| case BUILT_IN_BCOPY: |
| case BUILT_IN_MEMCPY: |
| case BUILT_IN_MEMMOVE: |
| case BUILT_IN_MEMPCPY: |
| /* Determine the type of the source object. */ |
| srctype = TREE_TYPE ((*args)[srcidx]); |
| if (!srctype || !INDIRECT_TYPE_P (srctype)) |
| srctype = void_type_node; |
| else |
| srctype = TREE_TYPE (srctype); |
| |
| /* Since it's impossible to determine wheter the byte copy is |
| being used in place of assignment to an existing object or |
| as a substitute for initialization, assume it's the former. |
| Determine the best alternative to use instead depending on |
| what's not deleted. */ |
| if (hasassign && hasctors[1]) |
| suggest = G_("; use copy-assignment or copy-initialization instead"); |
| else if (hasassign) |
| suggest = G_("; use copy-assignment instead"); |
| else if (hasctors[1]) |
| suggest = G_("; use copy-initialization instead"); |
| |
| if (!trivassign) |
| warnfmt = G_("%qD writing to an object of type %#qT with no trivial " |
| "copy-assignment%s"); |
| else if (!trivially_copyable_p (desttype)) |
| warnfmt = G_("%qD writing to an object of non-trivially copyable " |
| "type %#qT%s"); |
| else if (!trivcopy) |
| warnfmt = G_("%qD writing to an object with a deleted copy constructor"); |
| |
| else if (!trivial |
| && !VOID_TYPE_P (srctype) |
| && !char_type_p (TYPE_MAIN_VARIANT (srctype)) |
| && !same_type_ignoring_top_level_qualifiers_p (desttype, |
| srctype)) |
| { |
| /* Warn when copying into a non-trivial object from an object |
| of a different type other than void or char. */ |
| warned = warning_at (loc, OPT_Wclass_memaccess, |
| "%qD copying an object of non-trivial type " |
| "%#qT from an array of %#qT", |
| fndecl, desttype, srctype); |
| } |
| else if (fld |
| && !VOID_TYPE_P (srctype) |
| && !char_type_p (TYPE_MAIN_VARIANT (srctype)) |
| && !same_type_ignoring_top_level_qualifiers_p (desttype, |
| srctype)) |
| { |
| const char *access = TREE_PRIVATE (fld) ? "private" : "protected"; |
| warned = warning_at (loc, OPT_Wclass_memaccess, |
| "%qD copying an object of type %#qT with " |
| "%qs member %qD from an array of %#qT; use " |
| "assignment or copy-initialization instead", |
| fndecl, desttype, access, fld, srctype); |
| } |
| else if (!trivial && vec_safe_length (args) > 2) |
| { |
| tree sz = maybe_constant_value ((*args)[2]); |
| if (!tree_fits_uhwi_p (sz)) |
| break; |
| |
| /* Finally, warn on partial copies. */ |
| unsigned HOST_WIDE_INT typesize |
| = tree_to_uhwi (TYPE_SIZE_UNIT (desttype)); |
| if (unsigned HOST_WIDE_INT partial = tree_to_uhwi (sz) % typesize) |
| warned = warning_at (loc, OPT_Wclass_memaccess, |
| (typesize - partial > 1 |
| ? G_("%qD writing to an object of " |
| "a non-trivial type %#qT leaves %wu " |
| "bytes unchanged") |
| : G_("%qD writing to an object of " |
| "a non-trivial type %#qT leaves %wu " |
| "byte unchanged")), |
| fndecl, desttype, typesize - partial); |
| } |
| break; |
| |
| case BUILT_IN_REALLOC: |
| |
| if (!trivially_copyable_p (desttype)) |
| warnfmt = G_("%qD moving an object of non-trivially copyable type " |
| "%#qT; use %<new%> and %<delete%> instead"); |
| else if (!trivcopy) |
| warnfmt = G_("%qD moving an object of type %#qT with deleted copy " |
| "constructor; use %<new%> and %<delete%> instead"); |
| else if (!get_dtor (desttype, tf_none)) |
| warnfmt = G_("%qD moving an object of type %#qT with deleted " |
| "destructor"); |
| else if (!trivial) |
| { |
| tree sz = maybe_constant_value ((*args)[1]); |
| if (TREE_CODE (sz) == INTEGER_CST |
| && tree_int_cst_lt (sz, TYPE_SIZE_UNIT (desttype))) |
| /* Finally, warn on reallocation into insufficient space. */ |
| warned = warning_at (loc, OPT_Wclass_memaccess, |
| "%qD moving an object of non-trivial type " |
| "%#qT and size %E into a region of size %E", |
| fndecl, desttype, TYPE_SIZE_UNIT (desttype), |
| sz); |
| } |
| break; |
| |
| default: |
| return; |
| } |
| |
| if (warnfmt) |
| { |
| if (suggest) |
| warned = warning_at (loc, OPT_Wclass_memaccess, |
| warnfmt, fndecl, desttype, suggest); |
| else |
| warned = warning_at (loc, OPT_Wclass_memaccess, |
| warnfmt, fndecl, desttype); |
| } |
| |
| if (warned) |
| inform (location_of (desttype), "%#qT declared here", desttype); |
| } |
| |
| /* Build and return a call to FN, using NARGS arguments in ARGARRAY. |
| If FN is the result of resolving an overloaded target built-in, |
| ORIG_FNDECL is the original function decl, otherwise it is null. |
| This function performs no overload resolution, conversion, or other |
| high-level operations. */ |
| |
| tree |
| build_cxx_call (tree fn, int nargs, tree *argarray, |
| tsubst_flags_t complain, tree orig_fndecl) |
| { |
| tree fndecl; |
| |
| /* Remember roughly where this call is. */ |
| location_t loc = cp_expr_loc_or_input_loc (fn); |
| fn = build_call_a (fn, nargs, argarray); |
| SET_EXPR_LOCATION (fn, loc); |
| |
| fndecl = get_callee_fndecl (fn); |
| if (!orig_fndecl) |
| orig_fndecl = fndecl; |
| |
| /* Check that arguments to builtin functions match the expectations. */ |
| if (fndecl |
| && !processing_template_decl |
| && fndecl_built_in_p (fndecl)) |
| { |
| int i; |
| |
| /* We need to take care that values to BUILT_IN_NORMAL |
| are reduced. */ |
| for (i = 0; i < nargs; i++) |
| argarray[i] = maybe_constant_value (argarray[i]); |
| |
| if (!check_builtin_function_arguments (EXPR_LOCATION (fn), vNULL, fndecl, |
| orig_fndecl, nargs, argarray)) |
| return error_mark_node; |
| } |
| |
| if (VOID_TYPE_P (TREE_TYPE (fn))) |
| return fn; |
| |
| /* 5.2.2/11: If a function call is a prvalue of object type: if the |
| function call is either the operand of a decltype-specifier or the |
| right operand of a comma operator that is the operand of a |
| decltype-specifier, a temporary object is not introduced for the |
| prvalue. The type of the prvalue may be incomplete. */ |
| if (!(complain & tf_decltype)) |
| { |
| fn = require_complete_type_sfinae (fn, complain); |
| if (fn == error_mark_node) |
| return error_mark_node; |
| |
| if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn))) |
| { |
| fn = build_cplus_new (TREE_TYPE (fn), fn, complain); |
| maybe_warn_parm_abi (TREE_TYPE (fn), loc); |
| } |
| } |
| return convert_from_reference (fn); |
| } |
| |
| /* Returns the value to use for the in-charge parameter when making a |
| call to a function with the indicated NAME. |
| |
| FIXME:Can't we find a neater way to do this mapping? */ |
| |
| tree |
| in_charge_arg_for_name (tree name) |
| { |
| if (IDENTIFIER_CTOR_P (name)) |
| { |
| if (name == complete_ctor_identifier) |
| return integer_one_node; |
| gcc_checking_assert (name == base_ctor_identifier); |
| } |
| else |
| { |
| if (name == complete_dtor_identifier) |
| return integer_two_node; |
| else if (name == deleting_dtor_identifier) |
| return integer_three_node; |
| gcc_checking_assert (name == base_dtor_identifier); |
| } |
| |
| return integer_zero_node; |
| } |
| |
| /* We've built up a constructor call RET. Complain if it delegates to the |
| constructor we're currently compiling. */ |
| |
| static void |
| check_self_delegation (tree ret) |
| { |
| if (TREE_CODE (ret) == TARGET_EXPR) |
| ret = TARGET_EXPR_INITIAL (ret); |
| tree fn = cp_get_callee_fndecl_nofold (ret); |
| if (fn && DECL_ABSTRACT_ORIGIN (fn) == current_function_decl) |
| error ("constructor delegates to itself"); |
| } |
| |
| /* Build a call to a constructor, destructor, or an assignment |
| operator for INSTANCE, an expression with class type. NAME |
| indicates the special member function to call; *ARGS are the |
| arguments. ARGS may be NULL. This may change ARGS. BINFO |
| indicates the base of INSTANCE that is to be passed as the `this' |
| parameter to the member function called. |
| |
| FLAGS are the LOOKUP_* flags to use when processing the call. |
| |
| If NAME indicates a complete object constructor, INSTANCE may be |
| NULL_TREE. In this case, the caller will call build_cplus_new to |
| store the newly constructed object into a VAR_DECL. */ |
| |
| tree |
| build_special_member_call (tree instance, tree name, vec<tree, va_gc> **args, |
| tree binfo, int flags, tsubst_flags_t complain) |
| { |
| tree fns; |
| /* The type of the subobject to be constructed or destroyed. */ |
| tree class_type; |
| vec<tree, va_gc> *allocated = NULL; |
| tree ret; |
| |
| gcc_assert (IDENTIFIER_CDTOR_P (name) || name == assign_op_identifier); |
| |
| if (error_operand_p (instance)) |
| return error_mark_node; |
| |
| if (IDENTIFIER_DTOR_P (name)) |
| { |
| gcc_assert (args == NULL || vec_safe_is_empty (*args)); |
| if (!type_build_dtor_call (TREE_TYPE (instance))) |
| /* Shortcut to avoid lazy destructor declaration. */ |
| return build_trivial_dtor_call (instance); |
| } |
| |
| if (TYPE_P (binfo)) |
| { |
| /* Resolve the name. */ |
| if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain)) |
| return error_mark_node; |
| |
| binfo = TYPE_BINFO (binfo); |
| } |
| |
| gcc_assert (binfo != NULL_TREE); |
| |
| class_type = BINFO_TYPE (binfo); |
| |
| /* Handle the special case where INSTANCE is NULL_TREE. */ |
| if (name == complete_ctor_identifier && !instance) |
| instance = build_dummy_object (class_type); |
| else |
| { |
| /* Convert to the base class, if necessary. */ |
| if (!same_type_ignoring_top_level_qualifiers_p |
| (TREE_TYPE (instance), BINFO_TYPE (binfo))) |
| { |
| if (IDENTIFIER_CDTOR_P (name)) |
| /* For constructors and destructors, either the base is |
| non-virtual, or it is virtual but we are doing the |
| conversion from a constructor or destructor for the |
| complete object. In either case, we can convert |
| statically. */ |
| instance = convert_to_base_statically (instance, binfo); |
| else |
| { |
| /* However, for assignment operators, we must convert |
| dynamically if the base is virtual. */ |
| gcc_checking_assert (name == assign_op_identifier); |
| instance = build_base_path (PLUS_EXPR, instance, |
| binfo, /*nonnull=*/1, complain); |
| } |
| } |
| } |
| |
| gcc_assert (instance != NULL_TREE); |
| |
| /* In C++17, "If the initializer expression is a prvalue and the |
| cv-unqualified version of the source type is the same class as the class |
| of the destination, the initializer expression is used to initialize the |
| destination object." Handle that here to avoid doing overload |
| resolution. */ |
| if (cxx_dialect >= cxx17 |
| && args && vec_safe_length (*args) == 1 |
| && !unsafe_return_slot_p (instance)) |
| { |
| tree arg = (**args)[0]; |
| |
| if (BRACE_ENCLOSED_INITIALIZER_P (arg) |
| && !TYPE_HAS_LIST_CTOR (class_type) |
| && CONSTRUCTOR_NELTS (arg) == 1) |
| arg = CONSTRUCTOR_ELT (arg, 0)->value; |
| |
| if ((TREE_CODE (arg) == TARGET_EXPR |
| || TREE_CODE (arg) == CONSTRUCTOR) |
| && (same_type_ignoring_top_level_qualifiers_p |
| (class_type, TREE_TYPE (arg)))) |
| { |
| if (is_dummy_object (instance)) |
| return arg; |
| else if (TREE_CODE (arg) == TARGET_EXPR) |
| TARGET_EXPR_DIRECT_INIT_P (arg) = true; |
| |
| if ((complain & tf_error) |
| && (flags & LOOKUP_DELEGATING_CONS)) |
| check_self_delegation (arg); |
| /* Avoid change of behavior on Wunused-var-2.C. */ |
| instance = mark_lvalue_use (instance); |
| return build2 (INIT_EXPR, class_type, instance, arg); |
| } |
| } |
| |
| fns = lookup_fnfields (binfo, name, 1); |
| |
| /* When making a call to a constructor or destructor for a subobject |
| that uses virtual base classes, pass down a pointer to a VTT for |
| the subobject. */ |
| if ((name == base_ctor_identifier |
| || name == base_dtor_identifier) |
| && CLASSTYPE_VBASECLASSES (class_type)) |
| { |
| tree vtt; |
| tree sub_vtt; |
| |
| /* If the current function is a complete object constructor |
| or destructor, then we fetch the VTT directly. |
| Otherwise, we look it up using the VTT we were given. */ |
| vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type)); |
| vtt = decay_conversion (vtt, complain); |
| if (vtt == error_mark_node) |
| return error_mark_node; |
| vtt = build_if_in_charge (vtt, current_vtt_parm); |
| if (BINFO_SUBVTT_INDEX (binfo)) |
| sub_vtt = fold_build_pointer_plus (vtt, BINFO_SUBVTT_INDEX (binfo)); |
| else |
| sub_vtt = vtt; |
| |
| if (args == NULL) |
| { |
| allocated = make_tree_vector (); |
| args = &allocated; |
| } |
| |
| vec_safe_insert (*args, 0, sub_vtt); |
| } |
| |
| ret = build_new_method_call (instance, fns, args, |
| TYPE_BINFO (BINFO_TYPE (binfo)), |
| flags, /*fn=*/NULL, |
| complain); |
| |
| if (allocated != NULL) |
| release_tree_vector (allocated); |
| |
| if ((complain & tf_error) |
| && (flags & LOOKUP_DELEGATING_CONS) |
| && name == complete_ctor_identifier) |
| check_self_delegation (ret); |
| |
| return ret; |
| } |
| |
| /* Return the NAME, as a C string. The NAME indicates a function that |
| is a member of TYPE. *FREE_P is set to true if the caller must |
| free the memory returned. |
| |
| Rather than go through all of this, we should simply set the names |
| of constructors and destructors appropriately, and dispense with |
| ctor_identifier, dtor_identifier, etc. */ |
| |
| static char * |
| name_as_c_string (tree name, tree type, bool *free_p) |
| { |
| const char *pretty_name; |
| |
| /* Assume that we will not allocate memory. */ |
| *free_p = false; |
| /* Constructors and destructors are special. */ |
| if (IDENTIFIER_CDTOR_P (name)) |
| { |
| pretty_name |
| = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))); |
| /* For a destructor, add the '~'. */ |
| if (IDENTIFIER_DTOR_P (name)) |
| { |
| pretty_name = concat ("~", pretty_name, NULL); |
| /* Remember that we need to free the memory allocated. */ |
| *free_p = true; |
| } |
| } |
| else if (IDENTIFIER_CONV_OP_P (name)) |
| { |
| pretty_name = concat ("operator ", |
| type_as_string_translate (TREE_TYPE (name), |
| TFF_PLAIN_IDENTIFIER), |
| NULL); |
| /* Remember that we need to free the memory allocated. */ |
| *free_p = true; |
| } |
| else |
| pretty_name = identifier_to_locale (IDENTIFIER_POINTER (name)); |
| |
| return CONST_CAST (char *, pretty_name); |
| } |
| |
| /* If CANDIDATES contains exactly one candidate, return it, otherwise |
| return NULL. */ |
| |
| static z_candidate * |
| single_z_candidate (z_candidate *candidates) |
| { |
| if (candidates == NULL) |
| return NULL; |
| |
| if (candidates->next) |
| return NULL; |
| |
| return candidates; |
| } |
| |
| /* If CANDIDATE is invalid due to a bad argument type, return the |
| pertinent conversion_info. |
| |
| Otherwise, return NULL. */ |
| |
| static const conversion_info * |
| maybe_get_bad_conversion_for_unmatched_call (const z_candidate *candidate) |
| { |
| /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */ |
| rejection_reason *r = candidate->reason; |
| |
| if (r == NULL) |
| return NULL; |
| |
| switch (r->code) |
| { |
| default: |
| return NULL; |
| |
| case rr_arg_conversion: |
| return &r->u.conversion; |
| |
| case rr_bad_arg_conversion: |
| return &r->u.bad_conversion; |
| } |
| } |
| |
| /* Issue an error and note complaining about a bad argument type at a |
| callsite with a single candidate FNDECL. |
| |
| ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which |
| case input_location is used). |
| FROM_TYPE is the type of the actual argument; TO_TYPE is the type of |
| the formal parameter. */ |
| |
| void |
| complain_about_bad_argument (location_t arg_loc, |
| tree from_type, tree to_type, |
| tree fndecl, int parmnum) |
| { |
| auto_diagnostic_group d; |
| range_label_for_type_mismatch rhs_label (from_type, to_type); |
| range_label *label = &rhs_label; |
| if (arg_loc == UNKNOWN_LOCATION) |
| { |
| arg_loc = input_location; |
| label = NULL; |
| } |
| gcc_rich_location richloc (arg_loc, label); |
| error_at (&richloc, |
| "cannot convert %qH to %qI", |
| from_type, to_type); |
| maybe_inform_about_fndecl_for_bogus_argument_init (fndecl, |
| parmnum); |
| } |
| |
| /* Subroutine of build_new_method_call_1, for where there are no viable |
| candidates for the call. */ |
| |
| static void |
| complain_about_no_candidates_for_method_call (tree instance, |
| z_candidate *candidates, |
| tree explicit_targs, |
| tree basetype, |
| tree optype, tree name, |
| bool skip_first_for_error, |
| vec<tree, va_gc> *user_args) |
| { |
| auto_diagnostic_group d; |
| if (!COMPLETE_OR_OPEN_TYPE_P (basetype)) |
| cxx_incomplete_type_error (instance, basetype); |
| else if (optype) |
| error ("no matching function for call to %<%T::operator %T(%A)%#V%>", |
| basetype, optype, build_tree_list_vec (user_args), |
| TREE_TYPE (instance)); |
| else |
| { |
| /* Special-case for when there's a single candidate that's failing |
| due to a bad argument type. */ |
| if (z_candidate *candidate = single_z_candidate (candidates)) |
| if (const conversion_info *conv |
| = maybe_get_bad_conversion_for_unmatched_call (candidate)) |
| { |
| tree from_type = conv->from; |
| if (!TYPE_P (conv->from)) |
| from_type = lvalue_type (conv->from); |
| complain_about_bad_argument (conv->loc, |
| from_type, conv->to_type, |
| candidate->fn, conv->n_arg); |
| return; |
| } |
| |
| tree arglist = build_tree_list_vec (user_args); |
| tree errname = name; |
| bool twiddle = false; |
| if (IDENTIFIER_CDTOR_P (errname)) |
| { |
| twiddle = IDENTIFIER_DTOR_P (errname); |
| errname = constructor_name (basetype); |
| } |
| if (explicit_targs) |
| errname = lookup_template_function (errname, explicit_targs); |
| if (skip_first_for_error) |
| arglist = TREE_CHAIN (arglist); |
| error ("no matching function for call to %<%T::%s%E(%A)%#V%>", |
| basetype, &"~"[!twiddle], errname, arglist, |
| TREE_TYPE (instance)); |
| } |
| print_z_candidates (location_of (name), candidates); |
| } |
| |
| /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will |
| be set, upon return, to the function called. ARGS may be NULL. |
| This may change ARGS. */ |
| |
| static tree |
| build_new_method_call_1 (tree instance, tree fns, vec<tree, va_gc> **args, |
| tree conversion_path, int flags, |
| tree *fn_p, tsubst_flags_t complain) |
| { |
| struct z_candidate *candidates = 0, *cand; |
| tree explicit_targs = NULL_TREE; |
| tree basetype = NULL_TREE; |
| tree access_binfo; |
| tree optype; |
| tree first_mem_arg = NULL_TREE; |
| tree name; |
| bool skip_first_for_error; |
| vec<tree, va_gc> *user_args; |
| tree call; |
| tree fn; |
| int template_only = 0; |
| bool any_viable_p; |
| tree orig_instance; |
| tree orig_fns; |
| vec<tree, va_gc> *orig_args = NULL; |
| void *p; |
| |
| gcc_assert (instance != NULL_TREE); |
| |
| /* We don't know what function we're going to call, yet. */ |
| if (fn_p) |
| *fn_p = NULL_TREE; |
| |
| if (error_operand_p (instance) |
| || !fns || error_operand_p (fns)) |
| return error_mark_node; |
| |
| if (!BASELINK_P (fns)) |
| { |
| if (complain & tf_error) |
| error ("call to non-function %qD", fns); |
| return error_mark_node; |
| } |
| |
| orig_instance = instance; |
| orig_fns = fns; |
| |
| /* Dismantle the baselink to collect all the information we need. */ |
| if (!conversion_path) |
| conversion_path = BASELINK_BINFO (fns); |
| access_binfo = BASELINK_ACCESS_BINFO (fns); |
| optype = BASELINK_OPTYPE (fns); |
| fns = BASELINK_FUNCTIONS (fns); |
| if (TREE_CODE (fns) == TEMPLATE_ID_EXPR) |
| { |
| explicit_targs = TREE_OPERAND (fns, 1); |
| fns = TREE_OPERAND (fns, 0); |
| template_only = 1; |
| } |
| gcc_assert (OVL_P (fns)); |
| fn = OVL_FIRST (fns); |
| name = DECL_NAME (fn); |
| |
| basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance)); |
| gcc_assert (CLASS_TYPE_P (basetype)); |
| |
| user_args = args == NULL ? NULL : *args; |
| /* Under DR 147 A::A() is an invalid constructor call, |
| not a functional cast. */ |
| if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn)) |
| { |
| if (! (complain & tf_error)) |
| return error_mark_node; |
| |
| basetype = DECL_CONTEXT (fn); |
| name = constructor_name (basetype); |
| auto_diagnostic_group d; |
| if (permerror (input_location, |
| "cannot call constructor %<%T::%D%> directly", |
| basetype, name)) |
| inform (input_location, "for a function-style cast, remove the " |
| "redundant %<::%D%>", name); |
| call = build_functional_cast (input_location, basetype, |
| build_tree_list_vec (user_args), |
| complain); |
| return call; |
| } |
| |
| if (processing_template_decl) |
| { |
| orig_args = args == NULL ? NULL : make_tree_vector_copy (*args); |
| instance = build_non_dependent_expr (instance); |
| if (args != NULL) |
| make_args_non_dependent (*args); |
| } |
| |
| /* Process the argument list. */ |
| if (args != NULL && *args != NULL) |
| { |
| *args = resolve_args (*args, complain); |
| if (*args == NULL) |
| return error_mark_node; |
| user_args = *args; |
| } |
| |
| /* Consider the object argument to be used even if we end up selecting a |
| static member function. */ |
| instance = mark_type_use (instance); |
| |
| /* Figure out whether to skip the first argument for the error |
| message we will display to users if an error occurs. We don't |
| want to display any compiler-generated arguments. The "this" |
| pointer hasn't been added yet. However, we must remove the VTT |
| pointer if this is a call to a base-class constructor or |
| destructor. */ |
| skip_first_for_error = false; |
| if (IDENTIFIER_CDTOR_P (name)) |
| { |
| /* Callers should explicitly indicate whether they want to ctor |
| the complete object or just the part without virtual bases. */ |
| gcc_assert (name != ctor_identifier); |
| |
| /* Remove the VTT pointer, if present. */ |
| if ((name == base_ctor_identifier || name == base_dtor_identifier) |
| && CLASSTYPE_VBASECLASSES (basetype)) |
| skip_first_for_error = true; |
| |
| /* It's OK to call destructors and constructors on cv-qualified |
| objects. Therefore, convert the INSTANCE to the unqualified |
| type, if necessary. */ |
| if (!same_type_p (basetype, TREE_TYPE (instance))) |
| { |
| instance = build_this (instance); |
| instance = build_nop (build_pointer_type (basetype), instance); |
| instance = build_fold_indirect_ref (instance); |
| } |
| } |
| else |
| gcc_assert (!DECL_DESTRUCTOR_P (fn) && !DECL_CONSTRUCTOR_P (fn)); |
| |
| /* For the overload resolution we need to find the actual `this` |
| that would be captured if the call turns out to be to a |
| non-static member function. Do not actually capture it at this |
| point. */ |
| if (DECL_CONSTRUCTOR_P (fn)) |
| /* Constructors don't use the enclosing 'this'. */ |
| first_mem_arg = instance; |
| else |
| first_mem_arg = maybe_resolve_dummy (instance, false); |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| /* The number of arguments artificial parms in ARGS; we subtract one because |
| there's no 'this' in ARGS. */ |
| unsigned skip = num_artificial_parms_for (fn) - 1; |
| |
| /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form |
| initializer, not T({ }). */ |
| if (DECL_CONSTRUCTOR_P (fn) |
| && vec_safe_length (user_args) > skip |
| && DIRECT_LIST_INIT_P ((*user_args)[skip])) |
| { |
| tree init_list = (*user_args)[skip]; |
| tree init = NULL_TREE; |
| |
| gcc_assert (user_args->length () == skip + 1 |
| && !(flags & LOOKUP_ONLYCONVERTING)); |
| |
| /* If the initializer list has no elements and T is a class type with |
| a default constructor, the object is value-initialized. Handle |
| this here so we don't need to handle it wherever we use |
| build_special_member_call. */ |
| if (CONSTRUCTOR_NELTS (init_list) == 0 |
| && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype) |
| /* For a user-provided default constructor, use the normal |
| mechanisms so that protected access works. */ |
| && type_has_non_user_provided_default_constructor (basetype) |
| && !processing_template_decl) |
| init = build_value_init (basetype, complain); |
| |
| /* If BASETYPE is an aggregate, we need to do aggregate |
| initialization. */ |
| else if (CP_AGGREGATE_TYPE_P (basetype)) |
| { |
| init = reshape_init (basetype, init_list, complain); |
| init = digest_init (basetype, init, complain); |
| } |
| |
| if (init) |
| { |
| if (is_dummy_object (instance)) |
| return get_target_expr_sfinae (init, complain); |
| init = build2 (INIT_EXPR, TREE_TYPE (instance), instance, init); |
| TREE_SIDE_EFFECTS (init) = true; |
| return init; |
| } |
| |
| /* Otherwise go ahead with overload resolution. */ |
| add_list_candidates (fns, first_mem_arg, user_args, |
| basetype, explicit_targs, template_only, |
| conversion_path, access_binfo, flags, |
| &candidates, complain); |
| } |
| else |
| add_candidates (fns, first_mem_arg, user_args, optype, |
| explicit_targs, template_only, conversion_path, |
| access_binfo, flags, &candidates, complain); |
| |
| any_viable_p = false; |
| candidates = splice_viable (candidates, false, &any_viable_p); |
| |
| if (!any_viable_p) |
| { |
| /* [dcl.init], 17.6.2.2: |
| |
| Otherwise, if no constructor is viable, the destination type is |
| a (possibly cv-qualified) aggregate class A, and the initializer |
| is a parenthesized expression-list, the object is initialized as |
| follows... |
| |
| We achieve this by building up a CONSTRUCTOR, as for list-init, |
| and setting CONSTRUCTOR_IS_PAREN_INIT to distinguish between |
| the two. */ |
| if (DECL_CONSTRUCTOR_P (fn) |
| && !(flags & LOOKUP_ONLYCONVERTING) |
| && cxx_dialect >= cxx2a |
| && CP_AGGREGATE_TYPE_P (basetype) |
| && !vec_safe_is_empty (user_args)) |
| { |
| /* Create a CONSTRUCTOR from ARGS, e.g. {1, 2} from <1, 2>. */ |
| tree list = build_tree_list_vec (user_args); |
| tree ctor = build_constructor_from_list (init_list_type_node, list); |
| CONSTRUCTOR_IS_DIRECT_INIT (ctor) = true; |
| CONSTRUCTOR_IS_PAREN_INIT (ctor) = true; |
| if (is_dummy_object (instance)) |
| return ctor; |
| else |
| { |
| ctor = digest_init (basetype, ctor, complain); |
| if (ctor == error_mark_node) |
| return error_mark_node; |
| ctor = build2 (INIT_EXPR, TREE_TYPE (instance), instance, ctor); |
| TREE_SIDE_EFFECTS (ctor) = true; |
| return ctor; |
| } |
| } |
| if (complain & tf_error) |
| complain_about_no_candidates_for_method_call (instance, candidates, |
| explicit_targs, basetype, |
| optype, name, |
| skip_first_for_error, |
| user_args); |
| call = error_mark_node; |
| } |
| else |
| { |
| cand = tourney (candidates, complain); |
| if (cand == 0) |
| { |
| char *pretty_name; |
| bool free_p; |
| tree arglist; |
| |
| if (complain & tf_error) |
| { |
| pretty_name = name_as_c_string (name, basetype, &free_p); |
| arglist = build_tree_list_vec (user_args); |
| if (skip_first_for_error) |
| arglist = TREE_CHAIN (arglist); |
| auto_diagnostic_group d; |
| if (!any_strictly_viable (candidates)) |
| error ("no matching function for call to %<%s(%A)%>", |
| pretty_name, arglist); |
| else |
| error ("call of overloaded %<%s(%A)%> is ambiguous", |
| pretty_name, arglist); |
| print_z_candidates (location_of (name), candidates); |
| if (free_p) |
| free (pretty_name); |
| } |
| call = error_mark_node; |
| } |
| else |
| { |
| fn = cand->fn; |
| call = NULL_TREE; |
| |
| if (!(flags & LOOKUP_NONVIRTUAL) |
| && DECL_PURE_VIRTUAL_P (fn) |
| && instance == current_class_ref |
| && (complain & tf_warning)) |
| { |
| /* This is not an error, it is runtime undefined |
| behavior. */ |
| if (!current_function_decl) |
| warning (0, "pure virtual %q#D called from " |
| "non-static data member initializer", fn); |
| else if (DECL_CONSTRUCTOR_P (current_function_decl) |
| || DECL_DESTRUCTOR_P (current_function_decl)) |
| warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) |
| ? G_("pure virtual %q#D called from constructor") |
| : G_("pure virtual %q#D called from destructor")), |
| fn); |
| } |
| |
| if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE |
| && !DECL_CONSTRUCTOR_P (fn) |
| && is_dummy_object (instance)) |
| { |
| instance = maybe_resolve_dummy (instance, true); |
| if (instance == error_mark_node) |
| call = error_mark_node; |
| else if (!is_dummy_object (instance)) |
| { |
| /* We captured 'this' in the current lambda now that |
| we know we really need it. */ |
| cand->first_arg = instance; |
| } |
| else if (any_dependent_bases_p ()) |
| /* We can't tell until instantiation time whether we can use |
| *this as the implicit object argument. */; |
| else |
| { |
| if (complain & tf_error) |
| error ("cannot call member function %qD without object", |
| fn); |
| call = error_mark_node; |
| } |
| } |
| |
| if (call != error_mark_node) |
| { |
| if (explicit_targs) |
| flags |= LOOKUP_EXPLICIT_TMPL_ARGS; |
| /* Now we know what function is being called. */ |
| if (fn_p) |
| *fn_p = fn; |
| /* Build the actual CALL_EXPR. */ |
| call = build_over_call (cand, flags, complain); |
| /* In an expression of the form `a->f()' where `f' turns |
| out to be a static member function, `a' is |
| none-the-less evaluated. */ |
| if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE |
| && !is_dummy_object (instance) |
| && TREE_SIDE_EFFECTS (instance)) |
| { |
| /* But avoid the implicit lvalue-rvalue conversion when 'a' |
| is volatile. */ |
| tree a = instance; |
| if (TREE_THIS_VOLATILE (a)) |
| a = build_this (a); |
| if (TREE_SIDE_EFFECTS (a)) |
| call = build2 (COMPOUND_EXPR, TREE_TYPE (call), a, call); |
| } |
| else if (call != error_mark_node |
| && DECL_DESTRUCTOR_P (cand->fn) |
| && !VOID_TYPE_P (TREE_TYPE (call))) |
| /* An explicit call of the form "x->~X()" has type |
| "void". However, on platforms where destructors |
| return "this" (i.e., those where |
| targetm.cxx.cdtor_returns_this is true), such calls |
| will appear to have a return value of pointer type |
| to the low-level call machinery. We do not want to |
| change the low-level machinery, since we want to be |
| able to optimize "delete f()" on such platforms as |
| "operator delete(~X(f()))" (rather than generating |
| "t = f(), ~X(t), operator delete (t)"). */ |
| call = build_nop (void_type_node, call); |
| } |
| } |
| } |
| |
| if (processing_template_decl && call != error_mark_node) |
| { |
| bool cast_to_void = false; |
| |
| if (TREE_CODE (call) == COMPOUND_EXPR) |
| call = TREE_OPERAND (call, 1); |
| else if (TREE_CODE (call) == NOP_EXPR) |
| { |
| cast_to_void = true; |
| call = TREE_OPERAND (call, 0); |
| } |
| if (INDIRECT_REF_P (call)) |
| call = TREE_OPERAND (call, 0); |
| call = (build_min_non_dep_call_vec |
| (call, |
| build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)), |
| orig_instance, orig_fns, NULL_TREE), |
| orig_args)); |
| SET_EXPR_LOCATION (call, input_location); |
| call = convert_from_reference (call); |
| if (cast_to_void) |
| call = build_nop (void_type_node, call); |
| } |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| if (orig_args != NULL) |
| release_tree_vector (orig_args); |
| |
| return call; |
| } |
| |
| /* Wrapper for above. */ |
| |
| tree |
| build_new_method_call (tree instance, tree fns, vec<tree, va_gc> **args, |
| tree conversion_path, int flags, |
| tree *fn_p, tsubst_flags_t complain) |
| { |
| tree ret; |
| bool subtime = timevar_cond_start (TV_OVERLOAD); |
| ret = build_new_method_call_1 (instance, fns, args, conversion_path, flags, |
| fn_p, complain); |
| timevar_cond_stop (TV_OVERLOAD, subtime); |
| return ret; |
| } |
| |
| /* Returns true iff standard conversion sequence ICS1 is a proper |
| subsequence of ICS2. */ |
| |
| static bool |
| is_subseq (conversion *ics1, conversion *ics2) |
| { |
| /* We can assume that a conversion of the same code |
| between the same types indicates a subsequence since we only get |
| here if the types we are converting from are the same. */ |
| |
| while (ics1->kind == ck_rvalue |
| || ics1->kind == ck_lvalue) |
| ics1 = next_conversion (ics1); |
| |
| while (1) |
| { |
| while (ics2->kind == ck_rvalue |
| || ics2->kind == ck_lvalue) |
| ics2 = next_conversion (ics2); |
| |
| if (ics2->kind == ck_user |
| || ics2->kind == ck_ambig |
| || ics2->kind == ck_aggr |
| || ics2->kind == ck_list |
| || ics2->kind == ck_identity) |
| /* At this point, ICS1 cannot be a proper subsequence of |
| ICS2. We can get a USER_CONV when we are comparing the |
| second standard conversion sequence of two user conversion |
| sequences. */ |
| return false; |
| |
| ics2 = next_conversion (ics2); |
| |
| while (ics2->kind == ck_rvalue |
| || ics2->kind == ck_lvalue) |
| ics2 = next_conversion (ics2); |
| |
| if (ics2->kind == ics1->kind |
| && same_type_p (ics2->type, ics1->type) |
| && (ics1->kind == ck_identity |
| || same_type_p (next_conversion (ics2)->type, |
| next_conversion (ics1)->type))) |
| return true; |
| } |
| } |
| |
| /* Returns nonzero iff DERIVED is derived from BASE. The inputs may |
| be any _TYPE nodes. */ |
| |
| bool |
| is_properly_derived_from (tree derived, tree base) |
| { |
| if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base)) |
| return false; |
| |
| /* We only allow proper derivation here. The DERIVED_FROM_P macro |
| considers every class derived from itself. */ |
| return (!same_type_ignoring_top_level_qualifiers_p (derived, base) |
| && DERIVED_FROM_P (base, derived)); |
| } |
| |
| /* We build the ICS for an implicit object parameter as a pointer |
| conversion sequence. However, such a sequence should be compared |
| as if it were a reference conversion sequence. If ICS is the |
| implicit conversion sequence for an implicit object parameter, |
| modify it accordingly. */ |
| |
| static void |
| maybe_handle_implicit_object (conversion **ics) |
| { |
| if ((*ics)->this_p) |
| { |
| /* [over.match.funcs] |
| |
| For non-static member functions, the type of the |
| implicit object parameter is "reference to cv X" |
| where X is the class of which the function is a |
| member and cv is the cv-qualification on the member |
| function declaration. */ |
| conversion *t = *ics; |
| tree reference_type; |
| |
| /* The `this' parameter is a pointer to a class type. Make the |
| implicit conversion talk about a reference to that same class |
| type. */ |
| reference_type = TREE_TYPE (t->type); |
| reference_type = build_reference_type (reference_type); |
| |
| if (t->kind == ck_qual) |
| t = next_conversion (t); |
| if (t->kind == ck_ptr) |
| t = next_conversion (t); |
| t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE); |
| t = direct_reference_binding (reference_type, t); |
| t->this_p = 1; |
| t->rvaluedness_matches_p = 0; |
| *ics = t; |
| } |
| } |
| |
| /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion, |
| and return the initial reference binding conversion. Otherwise, |
| leave *ICS unchanged and return NULL. */ |
| |
| static conversion * |
| maybe_handle_ref_bind (conversion **ics) |
| { |
| if ((*ics)->kind == ck_ref_bind) |
| { |
| conversion *old_ics = *ics; |
| *ics = next_conversion (old_ics); |
| (*ics)->user_conv_p = old_ics->user_conv_p; |
| return old_ics; |
| } |
| |
| return NULL; |
| } |
| |
| /* Get the expression at the beginning of the conversion chain C. */ |
| |
| static tree |
| conv_get_original_expr (conversion *c) |
| { |
| for (; c; c = next_conversion (c)) |
| if (c->kind == ck_identity || c->kind == ck_ambig || c->kind == ck_aggr) |
| return c->u.expr; |
| return NULL_TREE; |
| } |
| |
| /* Return a tree representing the number of elements initialized by the |
| list-initialization C. The caller must check that C converts to an |
| array type. */ |
| |
| static tree |
| nelts_initialized_by_list_init (conversion *c) |
| { |
| /* If the array we're converting to has a dimension, we'll use that. */ |
| if (TYPE_DOMAIN (c->type)) |
| return array_type_nelts_top (c->type); |
| else |
| { |
| /* Otherwise, we look at how many elements the constructor we're |
| initializing from has. */ |
| tree ctor = conv_get_original_expr (c); |
| return size_int (CONSTRUCTOR_NELTS (ctor)); |
| } |
| } |
| |
| /* True iff C is a conversion that binds a reference or a pointer to |
| an array of unknown bound. */ |
| |
| static inline bool |
| conv_binds_to_array_of_unknown_bound (conversion *c) |
| { |
| /* ck_ref_bind won't have the reference stripped. */ |
| tree type = non_reference (c->type); |
| /* ck_qual won't have the pointer stripped. */ |
| type = strip_pointer_operator (type); |
| return (TREE_CODE (type) == ARRAY_TYPE |
| && TYPE_DOMAIN (type) == NULL_TREE); |
| } |
| |
| /* Compare two implicit conversion sequences according to the rules set out in |
| [over.ics.rank]. Return values: |
| |
| 1: ics1 is better than ics2 |
| -1: ics2 is better than ics1 |
| 0: ics1 and ics2 are indistinguishable */ |
| |
| static int |
| compare_ics (conversion *ics1, conversion *ics2) |
| { |
| tree from_type1; |
| tree from_type2; |
| tree to_type1; |
| tree to_type2; |
| tree deref_from_type1 = NULL_TREE; |
| tree deref_from_type2 = NULL_TREE; |
| tree deref_to_type1 = NULL_TREE; |
| tree deref_to_type2 = NULL_TREE; |
| conversion_rank rank1, rank2; |
| |
| /* REF_BINDING is nonzero if the result of the conversion sequence |
| is a reference type. In that case REF_CONV is the reference |
| binding conversion. */ |
| conversion *ref_conv1; |
| conversion *ref_conv2; |
| |
| /* Compare badness before stripping the reference conversion. */ |
| if (ics1->bad_p > ics2->bad_p) |
| return -1; |
| else if (ics1->bad_p < ics2->bad_p) |
| return 1; |
| |
| /* Handle implicit object parameters. */ |
| maybe_handle_implicit_object (&ics1); |
| maybe_handle_implicit_object (&ics2); |
| |
| /* Handle reference parameters. */ |
| ref_conv1 = maybe_handle_ref_bind (&ics1); |
| ref_conv2 = maybe_handle_ref_bind (&ics2); |
| |
| /* List-initialization sequence L1 is a better conversion sequence than |
| list-initialization sequence L2 if L1 converts to |
| std::initializer_list<X> for some X and L2 does not. */ |
| if (ics1->kind == ck_list && ics2->kind != ck_list) |
| return 1; |
| if (ics2->kind == ck_list && ics1->kind != ck_list) |
| return -1; |
| |
| /* [over.ics.rank] |
| |
| When comparing the basic forms of implicit conversion sequences (as |
| defined in _over.best.ics_) |
| |
| --a standard conversion sequence (_over.ics.scs_) is a better |
| conversion sequence than a user-defined conversion sequence |
| or an ellipsis conversion sequence, and |
| |
| --a user-defined conversion sequence (_over.ics.user_) is a |
| better conversion sequence than an ellipsis conversion sequence |
| (_over.ics.ellipsis_). */ |
| /* Use BAD_CONVERSION_RANK because we already checked for a badness |
| mismatch. If both ICS are bad, we try to make a decision based on |
| what would have happened if they'd been good. This is not an |
| extension, we'll still give an error when we build up the call; this |
| just helps us give a more helpful error message. */ |
| rank1 = BAD_CONVERSION_RANK (ics1); |
| rank2 = BAD_CONVERSION_RANK (ics2); |
| |
| if (rank1 > rank2) |
| return -1; |
| else if (rank1 < rank2) |
| return 1; |
| |
| if (ics1->ellipsis_p) |
| /* Both conversions are ellipsis conversions. */ |
| return 0; |
| |
| /* User-defined conversion sequence U1 is a better conversion sequence |
| than another user-defined conversion sequence U2 if they contain the |
| same user-defined conversion operator or constructor and if the sec- |
| ond standard conversion sequence of U1 is better than the second |
| standard conversion sequence of U2. */ |
| |
| /* Handle list-conversion with the same code even though it isn't always |
| ranked as a user-defined conversion and it doesn't have a second |
| standard conversion sequence; it will still have the desired effect. |
| Specifically, we need to do the reference binding comparison at the |
| end of this function. */ |
| |
| if (ics1->user_conv_p || ics1->kind == ck_list |
| || ics1->kind == ck_aggr || ics2->kind == ck_aggr) |
| { |
| conversion *t1 = strip_standard_conversion (ics1); |
| conversion *t2 = strip_standard_conversion (ics2); |
| |
| if (!t1 || !t2 || t1->kind != t2->kind) |
| return 0; |
| else if (t1->kind == ck_user) |
| { |
| tree f1 = t1->cand ? t1->cand->fn : t1->type; |
| tree f2 = t2->cand ? t2->cand->fn : t2->type; |
| if (f1 != f2) |
| return 0; |
| } |
| /* List-initialization sequence L1 is a better conversion sequence than |
| list-initialization sequence L2 if |
| |
| -- L1 and L2 convert to arrays of the same element type, and either |
| the number of elements n1 initialized by L1 is less than the number |
| of elements n2 initialized by L2, or n1=n2 and L2 converts to an array |
| of unknown bound and L1 does not. (Added in CWG 1307 and extended by |
| P0388R4.) */ |
| else if (t1->kind == ck_aggr |
| && TREE_CODE (t1->type) == ARRAY_TYPE |
| && TREE_CODE (t2->type) == ARRAY_TYPE) |
| { |
| /* The type of the array elements must be the same. */ |
| if (!same_type_p (TREE_TYPE (t1->type), TREE_TYPE (t2->type))) |
| return 0; |
| |
| tree n1 = nelts_initialized_by_list_init (t1); |
| tree n2 = nelts_initialized_by_list_init (t2); |
| if (tree_int_cst_lt (n1, n2)) |
| return 1; |
| else if (tree_int_cst_lt (n2, n1)) |
| return -1; |
| /* The n1 == n2 case. */ |
| bool c1 = conv_binds_to_array_of_unknown_bound (t1); |
| bool c2 = conv_binds_to_array_of_unknown_bound (t2); |
| if (c1 && !c2) |
| return -1; |
| else if (!c1 && c2) |
| return 1; |
| else |
| return 0; |
| } |
| else |
| { |
| /* For ambiguous or aggregate conversions, use the target type as |
| a proxy for the conversion function. */ |
| if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type)) |
| return 0; |
| } |
| |
| /* We can just fall through here, after setting up |
| FROM_TYPE1 and FROM_TYPE2. */ |
| from_type1 = t1->type; |
| from_type2 = t2->type; |
| } |
| else |
| { |
| conversion *t1; |
| conversion *t2; |
| |
| /* We're dealing with two standard conversion sequences. |
| |
| [over.ics.rank] |
| |
| Standard conversion sequence S1 is a better conversion |
| sequence than standard conversion sequence S2 if |
| |
| --S1 is a proper subsequence of S2 (comparing the conversion |
| sequences in the canonical form defined by _over.ics.scs_, |
| excluding any Lvalue Transformation; the identity |
| conversion sequence is considered to be a subsequence of |
| any non-identity conversion sequence */ |
| |
| t1 = ics1; |
| while (t1->kind != ck_identity) |
| t1 = next_conversion (t1); |
| from_type1 = t1->type; |
| |
| t2 = ics2; |
| while (t2->kind != ck_identity) |
| t2 = next_conversion (t2); |
| from_type2 = t2->type; |
| } |
| |
| /* One sequence can only be a subsequence of the other if they start with |
| the same type. They can start with different types when comparing the |
| second standard conversion sequence in two user-defined conversion |
| sequences. */ |
| if (same_type_p (from_type1, from_type2)) |
| { |
| if (is_subseq (ics1, ics2)) |
| return 1; |
| if (is_subseq (ics2, ics1)) |
| return -1; |
| } |
| |
| /* [over.ics.rank] |
| |
| Or, if not that, |
| |
| --the rank of S1 is better than the rank of S2 (by the rules |
| defined below): |
| |
| Standard conversion sequences are ordered by their ranks: an Exact |
| Match is a better conversion than a Promotion, which is a better |
| conversion than a Conversion. |
| |
| Two conversion sequences with the same rank are indistinguishable |
| unless one of the following rules applies: |
| |
| --A conversion that does not a convert a pointer, pointer to member, |
| or std::nullptr_t to bool is better than one that does. |
| |
| The ICS_STD_RANK automatically handles the pointer-to-bool rule, |
| so that we do not have to check it explicitly. */ |
| if (ics1->rank < ics2->rank) |
| return 1; |
| else if (ics2->rank < ics1->rank) |
| return -1; |
| |
| to_type1 = ics1->type; |
| to_type2 = ics2->type; |
| |
| /* A conversion from scalar arithmetic type to complex is worse than a |
| conversion between scalar arithmetic types. */ |
| if (same_type_p (from_type1, from_type2) |
| && ARITHMETIC_TYPE_P (from_type1) |
| && ARITHMETIC_TYPE_P (to_type1) |
| && ARITHMETIC_TYPE_P (to_type2) |
| && ((TREE_CODE (to_type1) == COMPLEX_TYPE) |
| != (TREE_CODE (to_type2) == COMPLEX_TYPE))) |
| { |
| if (TREE_CODE (to_type1) == COMPLEX_TYPE) |
| return -1; |
| else |
| return 1; |
| } |
| |
| if (TYPE_PTR_P (from_type1) |
| && TYPE_PTR_P (from_type2) |
| && TYPE_PTR_P (to_type1) |
| && TYPE_PTR_P (to_type2)) |
| { |
| deref_from_type1 = TREE_TYPE (from_type1); |
| deref_from_type2 = TREE_TYPE (from_type2); |
| deref_to_type1 = TREE_TYPE (to_type1); |
| deref_to_type2 = TREE_TYPE (to_type2); |
| } |
| /* The rules for pointers to members A::* are just like the rules |
| for pointers A*, except opposite: if B is derived from A then |
| A::* converts to B::*, not vice versa. For that reason, we |
| switch the from_ and to_ variables here. */ |
| else if ((TYPE_PTRDATAMEM_P (from_type1) && TYPE_PTRDATAMEM_P (from_type2) |
| && TYPE_PTRDATAMEM_P (to_type1) && TYPE_PTRDATAMEM_P (to_type2)) |
| || (TYPE_PTRMEMFUNC_P (from_type1) |
| && TYPE_PTRMEMFUNC_P (from_type2) |
| && TYPE_PTRMEMFUNC_P (to_type1) |
| && TYPE_PTRMEMFUNC_P (to_type2))) |
| { |
| deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1); |
| deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2); |
| deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1); |
| deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2); |
| } |
| |
| if (deref_from_type1 != NULL_TREE |
| && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1)) |
| && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2))) |
| { |
| /* This was one of the pointer or pointer-like conversions. |
| |
| [over.ics.rank] |
| |
| --If class B is derived directly or indirectly from class A, |
| conversion of B* to A* is better than conversion of B* to |
| void*, and conversion of A* to void* is better than |
| conversion of B* to void*. */ |
| if (VOID_TYPE_P (deref_to_type1) |
| && VOID_TYPE_P (deref_to_type2)) |
| { |
| if (is_properly_derived_from (deref_from_type1, |
| deref_from_type2)) |
| return -1; |
| else if (is_properly_derived_from (deref_from_type2, |
| deref_from_type1)) |
| return 1; |
| } |
| else if (VOID_TYPE_P (deref_to_type1) |
| || VOID_TYPE_P (deref_to_type2)) |
| { |
| if (same_type_p (deref_from_type1, deref_from_type2)) |
| { |
| if (VOID_TYPE_P (deref_to_type2)) |
| { |
| if (is_properly_derived_from (deref_from_type1, |
| deref_to_type1)) |
| return 1; |
| } |
| /* We know that DEREF_TO_TYPE1 is `void' here. */ |
| else if (is_properly_derived_from (deref_from_type1, |
| deref_to_type2)) |
| return -1; |
| } |
| } |
| else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1)) |
| && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2))) |
| { |
| /* [over.ics.rank] |
| |
| --If class B is derived directly or indirectly from class A |
| and class C is derived directly or indirectly from B, |
| |
| --conversion of C* to B* is better than conversion of C* to |
| A*, |
| |
| --conversion of B* to A* is better than conversion of C* to |
| A* */ |
| if (same_type_p (deref_from_type1, deref_from_type2)) |
| { |
| if (is_properly_derived_from (deref_to_type1, |
| deref_to_type2)) |
| return 1; |
| else if (is_properly_derived_from (deref_to_type2, |
| deref_to_type1)) |
| return -1; |
| } |
| else if (same_type_p (deref_to_type1, deref_to_type2)) |
| { |
| if (is_properly_derived_from (deref_from_type2, |
| deref_from_type1)) |
| return 1; |
| else if (is_properly_derived_from (deref_from_type1, |
| deref_from_type2)) |
| return -1; |
| } |
| } |
| } |
| else if (CLASS_TYPE_P (non_reference (from_type1)) |
| && same_type_p (from_type1, from_type2)) |
| { |
| tree from = non_reference (from_type1); |
| |
| /* [over.ics.rank] |
| |
| --binding of an expression of type C to a reference of type |
| B& is better than binding an expression of type C to a |
| reference of type A& |
| |
| --conversion of C to B is better than conversion of C to A, */ |
| if (is_properly_derived_from (from, to_type1) |
| && is_properly_derived_from (from, to_type2)) |
| { |
| if (is_properly_derived_from (to_type1, to_type2)) |
| return 1; |
| else if (is_properly_derived_from (to_type2, to_type1)) |
| return -1; |
| } |
| } |
| else if (CLASS_TYPE_P (non_reference (to_type1)) |
| && same_type_p (to_type1, to_type2)) |
| { |
| tree to = non_reference (to_type1); |
| |
| /* [over.ics.rank] |
| |
| --binding of an expression of type B to a reference of type |
| A& is better than binding an expression of type C to a |
| reference of type A&, |
| |
| --conversion of B to A is better than conversion of C to A */ |
| if (is_properly_derived_from (from_type1, to) |
| && is_properly_derived_from (from_type2, to)) |
| { |
| if (is_properly_derived_from (from_type2, from_type1)) |
| return 1; |
| else if (is_properly_derived_from (from_type1, from_type2)) |
| return -1; |
| } |
| } |
| |
| /* [over.ics.rank] |
| |
| --S1 and S2 differ only in their qualification conversion and yield |
| similar types T1 and T2 (_conv.qual_), respectively, and the cv- |
| qualification signature of type T1 is a proper subset of the cv- |
| qualification signature of type T2 */ |
| if (ics1->kind == ck_qual |
| && ics2->kind == ck_qual |
| && same_type_p (from_type1, from_type2)) |
| { |
| int result = comp_cv_qual_signature (to_type1, to_type2); |
| if (result != 0) |
| return result; |
| } |
| |
| /* [over.ics.rank] |
| |
| --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers |
| to an implicit object parameter of a non-static member function |
| declared without a ref-qualifier, and either S1 binds an lvalue |
| reference to an lvalue and S2 binds an rvalue reference or S1 binds an |
| rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x |
| draft standard, 13.3.3.2) |
| |
| --S1 and S2 are reference bindings (_dcl.init.ref_), and the |
| types to which the references refer are the same type except for |
| top-level cv-qualifiers, and the type to which the reference |
| initialized by S2 refers is more cv-qualified than the type to |
| which the reference initialized by S1 refers. |
| |
| DR 1328 [over.match.best]: the context is an initialization by |
| conversion function for direct reference binding (13.3.1.6) of a |
| reference to function type, the return type of F1 is the same kind of |
| reference (i.e. lvalue or rvalue) as the reference being initialized, |
| and the return type of F2 is not. */ |
| |
| if (ref_conv1 && ref_conv2) |
| { |
| if (!ref_conv1->this_p && !ref_conv2->this_p |
| && (ref_conv1->rvaluedness_matches_p |
| != ref_conv2->rvaluedness_matches_p) |
| && (same_type_p (ref_conv1->type, ref_conv2->type) |
| || (TYPE_REF_IS_RVALUE (ref_conv1->type) |
| != TYPE_REF_IS_RVALUE (ref_conv2->type)))) |
| { |
| if (ref_conv1->bad_p |
| && !same_type_p (TREE_TYPE (ref_conv1->type), |
| TREE_TYPE (ref_conv2->type))) |
| /* Don't prefer a bad conversion that drops cv-quals to a bad |
| conversion with the wrong rvalueness. */ |
| return 0; |
| return (ref_conv1->rvaluedness_matches_p |
| - ref_conv2->rvaluedness_matches_p); |
| } |
| |
| if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2)) |
| { |
| /* Per P0388R4: |
| |
| void f (int(&)[]), // (1) |
| f (int(&)[1]), // (2) |
| f (int*); // (3) |
| |
| (2) is better than (1), but (3) should be equal to (1) and to |
| (2). For that reason we don't use ck_qual for (1) which would |
| give it the cr_exact rank while (3) remains ck_identity. |
| Therefore we compare (1) and (2) here. For (1) we'll have |
| |
| ck_ref_bind <- ck_identity |
| int[] & int[1] |
| |
| so to handle this we must look at ref_conv. */ |
| bool c1 = conv_binds_to_array_of_unknown_bound (ref_conv1); |
| bool c2 = conv_binds_to_array_of_unknown_bound (ref_conv2); |
| if (c1 && !c2) |
| return -1; |
| else if (!c1 && c2) |
| return 1; |
| |
| int q1 = cp_type_quals (TREE_TYPE (ref_conv1->type)); |
| int q2 = cp_type_quals (TREE_TYPE (ref_conv2->type)); |
| if (ref_conv1->bad_p) |
| { |
| /* Prefer the one that drops fewer cv-quals. */ |
| tree ftype = next_conversion (ref_conv1)->type; |
| int fquals = cp_type_quals (ftype); |
| q1 ^= fquals; |
| q2 ^= fquals; |
| } |
| return comp_cv_qualification (q2, q1); |
| } |
| } |
| |
| /* [over.ics.rank] |
| |
| Per CWG 1601: |
| -- A conversion that promotes an enumeration whose underlying type |
| is fixed to its underlying type is better than one that promotes to |
| the promoted underlying type, if the two are different. */ |
| if (ics1->rank == cr_promotion |
| && ics2->rank == cr_promotion |
| && UNSCOPED_ENUM_P (from_type1) |
| && ENUM_FIXED_UNDERLYING_TYPE_P (from_type1) |
| && same_type_p (from_type1, from_type2)) |
| { |
| tree utype = ENUM_UNDERLYING_TYPE (from_type1); |
| tree prom = type_promotes_to (from_type1); |
| if (!same_type_p (utype, prom)) |
| { |
| if (same_type_p (to_type1, utype) |
| && same_type_p (to_type2, prom)) |
| return 1; |
| else if (same_type_p (to_type2, utype) |
| && same_type_p (to_type1, prom)) |
| return -1; |
| } |
| } |
| |
| /* Neither conversion sequence is better than the other. */ |
| return 0; |
| } |
| |
| /* The source type for this standard conversion sequence. */ |
| |
| static tree |
| source_type (conversion *t) |
| { |
| return strip_standard_conversion (t)->type; |
| } |
| |
| /* Note a warning about preferring WINNER to LOSER. We do this by storing |
| a pointer to LOSER and re-running joust to produce the warning if WINNER |
| is actually used. */ |
| |
| static void |
| add_warning (struct z_candidate *winner, struct z_candidate *loser) |
| { |
| candidate_warning *cw = (candidate_warning *) |
| conversion_obstack_alloc (sizeof (candidate_warning)); |
| cw->loser = loser; |
| cw->next = winner->warnings; |
| winner->warnings = cw; |
| } |
| |
| /* CAND is a constructor candidate in joust in C++17 and up. If it copies a |
| prvalue returned from a conversion function, replace CAND with the candidate |
| for the conversion and return true. Otherwise, return false. */ |
| |
| static bool |
| joust_maybe_elide_copy (z_candidate *&cand) |
| { |
| tree fn = cand->fn; |
| if (!DECL_COPY_CONSTRUCTOR_P (fn) && !DECL_MOVE_CONSTRUCTOR_P (fn)) |
| return false; |
| conversion *conv = cand->convs[0]; |
| gcc_checking_assert (conv->kind == ck_ref_bind); |
| conv = next_conversion (conv); |
| if (conv->kind == ck_user && !TYPE_REF_P (conv->type)) |
| { |
| gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p |
| (conv->type, DECL_CONTEXT (fn))); |
| z_candidate *uc = conv->cand; |
| if (DECL_CONV_FN_P (uc->fn)) |
| { |
| cand = uc; |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /* True if the defining declarations of the two candidates have equivalent |
| parameters. */ |
| |
| bool |
| cand_parms_match (z_candidate *c1, z_candidate *c2) |
| { |
| tree fn1 = c1->fn; |
| tree fn2 = c2->fn; |
| if (fn1 == fn2) |
| return true; |
| if (identifier_p (fn1) || identifier_p (fn2)) |
| return false; |
| /* We don't look at c1->template_decl because that's only set for primary |
| templates, not e.g. non-template member functions of class templates. */ |
| tree t1 = most_general_template (fn1); |
| tree t2 = most_general_template (fn2); |
| if (t1 || t2) |
| { |
| if (!t1 || !t2) |
| return false; |
| if (t1 == t2) |
| return true; |
| fn1 = DECL_TEMPLATE_RESULT (t1); |
| fn2 = DECL_TEMPLATE_RESULT (t2); |
| } |
| return compparms (TYPE_ARG_TYPES (TREE_TYPE (fn1)), |
| TYPE_ARG_TYPES (TREE_TYPE (fn2))); |
| } |
| |
| /* Compare two candidates for overloading as described in |
| [over.match.best]. Return values: |
| |
| 1: cand1 is better than cand2 |
| -1: cand2 is better than cand1 |
| 0: cand1 and cand2 are indistinguishable */ |
| |
| static int |
| joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn, |
| tsubst_flags_t complain) |
| { |
| int winner = 0; |
| int off1 = 0, off2 = 0; |
| size_t i; |
| size_t len; |
| |
| /* Candidates that involve bad conversions are always worse than those |
| that don't. */ |
| if (cand1->viable > cand2->viable) |
| return 1; |
| if (cand1->viable < cand2->viable) |
| return -1; |
| |
| /* If we have two pseudo-candidates for conversions to the same type, |
| or two candidates for the same function, arbitrarily pick one. */ |
| if (cand1->fn == cand2->fn |
| && cand1->reversed () == cand2->reversed () |
| && (IS_TYPE_OR_DECL_P (cand1->fn))) |
| return 1; |
| |
| /* Prefer a non-deleted function over an implicitly deleted move |
| constructor or assignment operator. This differs slightly from the |
| wording for issue 1402 (which says the move op is ignored by overload |
| resolution), but this way produces better error messages. */ |
| if (TREE_CODE (cand1->fn) == FUNCTION_DECL |
| && TREE_CODE (cand2->fn) == FUNCTION_DECL |
| && DECL_DELETED_FN (cand1->fn) != DECL_DELETED_FN (cand2->fn)) |
| { |
| if (DECL_DELETED_FN (cand1->fn) && DECL_DEFAULTED_FN (cand1->fn) |
| && move_fn_p (cand1->fn)) |
| return -1; |
| if (DECL_DELETED_FN (cand2->fn) && DECL_DEFAULTED_FN (cand2->fn) |
| && move_fn_p (cand2->fn)) |
| return 1; |
| } |
| |
| /* a viable function F1 |
| is defined to be a better function than another viable function F2 if |
| for all arguments i, ICSi(F1) is not a worse conversion sequence than |
| ICSi(F2), and then */ |
| |
| /* for some argument j, ICSj(F1) is a better conversion sequence than |
| ICSj(F2) */ |
| |
| /* For comparing static and non-static member functions, we ignore |
| the implicit object parameter of the non-static function. The |
| standard says to pretend that the static function has an object |
| parm, but that won't work with operator overloading. */ |
| len = cand1->num_convs; |
| if (len != cand2->num_convs) |
| { |
| int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn); |
| int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn); |
| |
| if (DECL_CONSTRUCTOR_P (cand1->fn) |
| && is_list_ctor (cand1->fn) != is_list_ctor (cand2->fn)) |
| /* We're comparing a near-match list constructor and a near-match |
| non-list constructor. Just treat them as unordered. */ |
| return 0; |
| |
| gcc_assert (static_1 != static_2); |
| |
| if (static_1) |
| off2 = 1; |
| else |
| { |
| off1 = 1; |
| --len; |
| } |
| } |
| |
| /* Handle C++17 copy elision in [over.match.ctor] (direct-init) context. The |
| standard currently says that only constructors are candidates, but if one |
| copies a prvalue returned by a conversion function we want to treat the |
| conversion as the candidate instead. |
| |
| Clang does something similar, as discussed at |
| http://lists.isocpp.org/core/2017/10/3166.php |
| http://lists.isocpp.org/core/2019/03/5721.php */ |
| int elided_tiebreaker = 0; |
| if (len == 1 && cxx_dialect >= cxx17 |
| && DECL_P (cand1->fn) |
| && DECL_COMPLETE_CONSTRUCTOR_P (cand1->fn) |
| && !(cand1->flags & LOOKUP_ONLYCONVERTING)) |
| { |
| bool elided1 = joust_maybe_elide_copy (cand1); |
| bool elided2 = joust_maybe_elide_copy (cand2); |
| /* As a tiebreaker below we will prefer a constructor to a conversion |
| operator exposed this way. */ |
| elided_tiebreaker = elided2 - elided1; |
| } |
| |
| for (i = 0; i < len; ++i) |
| { |
| conversion *t1 = cand1->convs[i + off1]; |
| conversion *t2 = cand2->convs[i + off2]; |
| int comp = compare_ics (t1, t2); |
| |
| if (comp != 0) |
| { |
| if ((complain & tf_warning) |
| && warn_sign_promo |
| && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2) |
| == cr_std + cr_promotion) |
| && t1->kind == ck_std |
| && t2->kind == ck_std |
| && TREE_CODE (t1->type) == INTEGER_TYPE |
| && TREE_CODE (t2->type) == INTEGER_TYPE |
| && (TYPE_PRECISION (t1->type) |
| == TYPE_PRECISION (t2->type)) |
| && (TYPE_UNSIGNED (next_conversion (t1)->type) |
| || (TREE_CODE (next_conversion (t1)->type) |
| == ENUMERAL_TYPE))) |
| { |
| tree type = next_conversion (t1)->type; |
| tree type1, type2; |
| struct z_candidate *w, *l; |
| if (comp > 0) |
| type1 = t1->type, type2 = t2->type, |
| w = cand1, l = cand2; |
| else |
| type1 = t2->type, type2 = t1->type, |
| w = cand2, l = cand1; |
| |
| if (warn) |
| { |
| warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT", |
| type, type1, type2); |
| warning (OPT_Wsign_promo, " in call to %qD", w->fn); |
| } |
| else |
| add_warning (w, l); |
| } |
| |
| if (winner && comp != winner) |
| { |
| /* Ambiguity between normal and reversed comparison operators |
| with the same parameter types; prefer the normal one. */ |
| if ((cand1->reversed () != cand2->reversed ()) |
| && cand_parms_match (cand1, cand2)) |
| return cand1->reversed () ? -1 : 1; |
| |
| winner = 0; |
| goto tweak; |
| } |
| winner = comp; |
| } |
| } |
| |
| /* warn about confusing overload resolution for user-defined conversions, |
| either between a constructor and a conversion op, or between two |
| conversion ops. */ |
| if ((complain & tf_warning) |
| /* In C++17, the constructor might have been elided, which means that |
| an originally null ->second_conv could become non-null. */ |
| && winner && warn_conversion && cand1->second_conv && cand2->second_conv |
| && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn)) |
| && winner != compare_ics (cand1->second_conv, cand2->second_conv)) |
| { |
| struct z_candidate *w, *l; |
| bool give_warning = false; |
| |
| if (winner == 1) |
| w = cand1, l = cand2; |
| else |
| w = cand2, l = cand1; |
| |
| /* We don't want to complain about `X::operator T1 ()' |
| beating `X::operator T2 () const', when T2 is a no less |
| cv-qualified version of T1. */ |
| if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn) |
| && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn)) |
| { |
| tree t = TREE_TYPE (TREE_TYPE (l->fn)); |
| tree f = TREE_TYPE (TREE_TYPE (w->fn)); |
| |
| if (TREE_CODE (t) == TREE_CODE (f) && INDIRECT_TYPE_P (t)) |
| { |
| t = TREE_TYPE (t); |
| f = TREE_TYPE (f); |
| } |
| if (!comp_ptr_ttypes (t, f)) |
| give_warning = true; |
| } |
| else |
| give_warning = true; |
| |
| if (!give_warning) |
| /*NOP*/; |
| else if (warn) |
| { |
| tree source = source_type (w->convs[0]); |
| if (INDIRECT_TYPE_P (source)) |
| source = TREE_TYPE (source); |
| auto_diagnostic_group d; |
| if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn) |
| && warning (OPT_Wconversion, " for conversion from %qH to %qI", |
| source, w->second_conv->type)) |
| { |
| inform (input_location, " because conversion sequence " |
| "for the argument is better"); |
| } |
| } |
| else |
| add_warning (w, l); |
| } |
| |
| if (winner) |
| return winner; |
| |
| /* Put this tiebreaker first, so that we don't try to look at second_conv of |
| a constructor candidate that doesn't have one. */ |
| if (elided_tiebreaker) |
| return elided_tiebreaker; |
| |
| /* DR 495 moved this tiebreaker above the template ones. */ |
| /* or, if not that, |
| the context is an initialization by user-defined conversion (see |
| _dcl.init_ and _over.match.user_) and the standard conversion |
| sequence from the return type of F1 to the destination type (i.e., |
| the type of the entity being initialized) is a better conversion |
| sequence than the standard conversion sequence from the return type |
| of F2 to the destination type. */ |
| |
| if (cand1->second_conv) |
| { |
| winner = compare_ics (cand1->second_conv, cand2->second_conv); |
| if (winner) |
| return winner; |
| } |
| |
| /* or, if not that, |
| F1 is a non-template function and F2 is a template function |
| specialization. */ |
| |
| if (!cand1->template_decl && cand2->template_decl) |
| return 1; |
| else if (cand1->template_decl && !cand2->template_decl) |
| return -1; |
| |
| /* or, if not that, |
| F1 and F2 are template functions and the function template for F1 is |
| more specialized than the template for F2 according to the partial |
| ordering rules. */ |
| |
| if (cand1->template_decl && cand2->template_decl) |
| { |
| winner = more_specialized_fn |
| (TI_TEMPLATE (cand1->template_decl), |
| TI_TEMPLATE (cand2->template_decl), |
| /* [temp.func.order]: The presence of unused ellipsis and default |
| arguments has no effect on the partial ordering of function |
| templates. add_function_candidate() will not have |
| counted the "this" argument for constructors. */ |
| cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn)); |
| if (winner) |
| return winner; |
| } |
| |
| /* Concepts: F1 and F2 are non-template functions with the same |
| parameter-type-lists, and F1 is more constrained than F2 according to the |
| partial ordering of constraints described in 13.5.4. */ |
| |
| if (flag_concepts && DECL_P (cand1->fn) && DECL_P (cand2->fn) |
| && !cand1->template_decl && !cand2->template_decl |
| && cand_parms_match (cand1, cand2)) |
| { |
| winner = more_constrained (cand1->fn, cand2->fn); |
| if (winner) |
| return winner; |
| } |
| |
| /* F2 is a rewritten candidate (12.4.1.2) and F1 is not, or F1 and F2 are |
| rewritten candidates, and F2 is a synthesized candidate with reversed |
| order of parameters and F1 is not. */ |
| if (cand1->rewritten ()) |
| { |
| if (!cand2->rewritten ()) |
| return -1; |
| if (!cand1->reversed () && cand2->reversed ()) |
| return 1; |
| if (cand1->reversed () && !cand2->reversed ()) |
| return -1; |
| } |
| else if (cand2->rewritten ()) |
| return 1; |
| |
| /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */ |
| if (deduction_guide_p (cand1->fn)) |
| { |
| gcc_assert (deduction_guide_p (cand2->fn)); |
| /* We distinguish between candidates from an explicit deduction guide and |
| candidates built from a constructor based on DECL_ARTIFICIAL. */ |
| int art1 = DECL_ARTIFICIAL (cand1->fn); |
| int art2 = DECL_ARTIFICIAL (cand2->fn); |
| if (art1 != art2) |
| return art2 - art1; |
| |
| if (art1) |
| { |
| /* Prefer the special copy guide over a declared copy/move |
| constructor. */ |
| if (copy_guide_p (cand1->fn)) |
| return 1; |
| if (copy_guide_p (cand2->fn)) |
| return -1; |
| |
| /* Prefer a candidate generated from a non-template constructor. */ |
| int tg1 = template_guide_p (cand1->fn); |
| int tg2 = template_guide_p (cand2->fn); |
| if (tg1 != tg2) |
| return tg2 - tg1; |
| } |
| } |
| |
| /* F1 is a member of a class D, F2 is a member of a base class B of D, and |
| for all arguments the corresponding parameters of F1 and F2 have the same |
| type (CWG 2273/2277). */ |
| if (DECL_P (cand1->fn) && DECL_CLASS_SCOPE_P (cand1->fn) |
| && !DECL_CONV_FN_P (cand1->fn) |
| && DECL_P (cand2->fn) && DECL_CLASS_SCOPE_P (cand2->fn) |
| && !DECL_CONV_FN_P (cand2->fn)) |
| { |
| tree base1 = DECL_CONTEXT (strip_inheriting_ctors (cand1->fn)); |
| tree base2 = DECL_CONTEXT (strip_inheriting_ctors (cand2->fn)); |
| |
| bool used1 = false; |
| bool used2 = false; |
| if (base1 == base2) |
| /* No difference. */; |
| else if (DERIVED_FROM_P (base1, base2)) |
| used1 = true; |
| else if (DERIVED_FROM_P (base2, base1)) |
| used2 = true; |
| |
| if (int diff = used2 - used1) |
| { |
| for (i = 0; i < len; ++i) |
| { |
| conversion *t1 = cand1->convs[i + off1]; |
| conversion *t2 = cand2->convs[i + off2]; |
| if (!same_type_p (t1->type, t2->type)) |
| break; |
| } |
| if (i == len) |
| return diff; |
| } |
| } |
| |
| /* Check whether we can discard a builtin candidate, either because we |
| have two identical ones or matching builtin and non-builtin candidates. |
| |
| (Pedantically in the latter case the builtin which matched the user |
| function should not be added to the overload set, but we spot it here. |
| |
| [over.match.oper] |
| ... the builtin candidates include ... |
| - do not have the same parameter type list as any non-template |
| non-member candidate. */ |
| |
| if (identifier_p (cand1->fn) || identifier_p (cand2->fn)) |
| { |
| for (i = 0; i < len; ++i) |
| if (!same_type_p (cand1->convs[i]->type, |
| cand2->convs[i]->type)) |
| break; |
| if (i == cand1->num_convs) |
| { |
| if (cand1->fn == cand2->fn) |
| /* Two built-in candidates; arbitrarily pick one. */ |
| return 1; |
| else if (identifier_p (cand1->fn)) |
| /* cand1 is built-in; prefer cand2. */ |
| return -1; |
| else |
| /* cand2 is built-in; prefer cand1. */ |
| return 1; |
| } |
| } |
| |
| /* For candidates of a multi-versioned function, make the version with |
| the highest priority win. This version will be checked for dispatching |
| first. If this version can be inlined into the caller, the front-end |
| will simply make a direct call to this function. */ |
| |
| if (TREE_CODE (cand1->fn) == FUNCTION_DECL |
| && DECL_FUNCTION_VERSIONED (cand1->fn) |
| && TREE_CODE (cand2->fn) == FUNCTION_DECL |
| && DECL_FUNCTION_VERSIONED (cand2->fn)) |
| { |
| tree f1 = TREE_TYPE (cand1->fn); |
| tree f2 = TREE_TYPE (cand2->fn); |
| tree p1 = TYPE_ARG_TYPES (f1); |
| tree p2 = TYPE_ARG_TYPES (f2); |
| |
| /* Check if cand1->fn and cand2->fn are versions of the same function. It |
| is possible that cand1->fn and cand2->fn are function versions but of |
| different functions. Check types to see if they are versions of the same |
| function. */ |
| if (compparms (p1, p2) |
| && same_type_p (TREE_TYPE (f1), TREE_TYPE (f2))) |
| { |
| /* Always make the version with the higher priority, more |
| specialized, win. */ |
| gcc_assert (targetm.compare_version_priority); |
| if (targetm.compare_version_priority (cand1->fn, cand2->fn) >= 0) |
| return 1; |
| else |
| return -1; |
| } |
| } |
| |
| /* If the two function declarations represent the same function (this can |
| happen with declarations in multiple scopes and arg-dependent lookup), |
| arbitrarily choose one. But first make sure the default args we're |
| using match. */ |
| if (DECL_P (cand1->fn) && DECL_P (cand2->fn) |
| && equal_functions (cand1->fn, cand2->fn)) |
| { |
| tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn)); |
| tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn)); |
| |
| gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn)); |
| |
| for (i = 0; i < len; ++i) |
| { |
| /* Don't crash if the fn is variadic. */ |
| if (!parms1) |
| break; |
| parms1 = TREE_CHAIN (parms1); |
| parms2 = TREE_CHAIN (parms2); |
| } |
| |
| if (off1) |
| parms1 = TREE_CHAIN (parms1); |
| else if (off2) |
| parms2 = TREE_CHAIN (parms2); |
| |
| for (; parms1; ++i) |
| { |
| if (!cp_tree_equal (TREE_PURPOSE (parms1), |
| TREE_PURPOSE (parms2))) |
| { |
| if (warn) |
| { |
| if (complain & tf_error) |
| { |
| auto_diagnostic_group d; |
| if (permerror (input_location, |
| "default argument mismatch in " |
| "overload resolution")) |
| { |
| inform (DECL_SOURCE_LOCATION (cand1->fn), |
| " candidate 1: %q#F", cand1->fn); |
| inform (DECL_SOURCE_LOCATION (cand2->fn), |
| " candidate 2: %q#F", cand2->fn); |
| } |
| } |
| else |
| return 0; |
| } |
| else |
| add_warning (cand1, cand2); |
| break; |
| } |
| parms1 = TREE_CHAIN (parms1); |
| parms2 = TREE_CHAIN (parms2); |
| } |
| |
| return 1; |
| } |
| |
| tweak: |
| |
| /* Extension: If the worst conversion for one candidate is better than the |
| worst conversion for the other, take the first. */ |
| if (!pedantic && (complain & tf_warning_or_error)) |
| { |
| conversion_rank rank1 = cr_identity, rank2 = cr_identity; |
| struct z_candidate *w = 0, *l = 0; |
| |
| for (i = 0; i < len; ++i) |
| { |
| if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1) |
| rank1 = CONVERSION_RANK (cand1->convs[i+off1]); |
| if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2) |
| rank2 = CONVERSION_RANK (cand2->convs[i + off2]); |
| } |
| if (rank1 < rank2) |
| winner = 1, w = cand1, l = cand2; |
| if (rank1 > rank2) |
| winner = -1, w = cand2, l = cand1; |
| if (winner) |
| { |
| /* Don't choose a deleted function over ambiguity. */ |
| if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn)) |
| return 0; |
| if (warn) |
| { |
| auto_diagnostic_group d; |
| if (pedwarn (input_location, 0, |
| "ISO C++ says that these are ambiguous, even " |
| "though the worst conversion for the first is " |
| "better than the worst conversion for the second:")) |
| { |
| print_z_candidate (input_location, N_("candidate 1:"), w); |
| print_z_candidate (input_location, N_("candidate 2:"), l); |
| } |
| } |
| else |
| add_warning (w, l); |
| return winner; |
| } |
| } |
| |
| gcc_assert (!winner); |
| return 0; |
| } |
| |
| /* Given a list of candidates for overloading, find the best one, if any. |
| This algorithm has a worst case of O(2n) (winner is last), and a best |
| case of O(n/2) (totally ambiguous); much better than a sorting |
| algorithm. */ |
| |
| static struct z_candidate * |
| tourney (struct z_candidate *candidates, tsubst_flags_t complain) |
| { |
| struct z_candidate *champ = candidates, *challenger; |
| int fate; |
| int champ_compared_to_predecessor = 0; |
| |
| /* Walk through the list once, comparing each current champ to the next |
| candidate, knocking out a candidate or two with each comparison. */ |
| |
| for (challenger = champ->next; challenger; ) |
| { |
| fate = joust (champ, challenger, 0, complain); |
| if (fate == 1) |
| challenger = challenger->next; |
| else |
| { |
| if (fate == 0) |
| { |
| champ = challenger->next; |
| if (champ == 0) |
| return NULL; |
| champ_compared_to_predecessor = 0; |
| } |
| else |
| { |
| champ = challenger; |
| champ_compared_to_predecessor = 1; |
| } |
| |
| challenger = champ->next; |
| } |
| } |
| |
| /* Make sure the champ is better than all the candidates it hasn't yet |
| been compared to. */ |
| |
| for (challenger = candidates; |
| challenger != champ |
| && !(champ_compared_to_predecessor && challenger->next == champ); |
| challenger = challenger->next) |
| { |
| fate = joust (champ, challenger, 0, complain); |
| if (fate != 1) |
| return NULL; |
| } |
| |
| return champ; |
| } |
| |
| /* Returns nonzero if things of type FROM can be converted to TO. */ |
| |
| bool |
| can_convert (tree to, tree from, tsubst_flags_t complain) |
| { |
| tree arg = NULL_TREE; |
| /* implicit_conversion only considers user-defined conversions |
| if it has an expression for the call argument list. */ |
| if (CLASS_TYPE_P (from) || CLASS_TYPE_P (to)) |
| arg = build1 (CAST_EXPR, from, NULL_TREE); |
| return can_convert_arg (to, from, arg, LOOKUP_IMPLICIT, complain); |
| } |
| |
| /* Returns nonzero if things of type FROM can be converted to TO with a |
| standard conversion. */ |
| |
| bool |
| can_convert_standard (tree to, tree from, tsubst_flags_t complain) |
| { |
| return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT, complain); |
| } |
| |
| /* Returns nonzero if ARG (of type FROM) can be converted to TO. */ |
| |
| bool |
| can_convert_arg (tree to, tree from, tree arg, int flags, |
| tsubst_flags_t complain) |
| { |
| conversion *t; |
| void *p; |
| bool ok_p; |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| /* We want to discard any access checks done for this test, |
| as we might not be in the appropriate access context and |
| we'll do the check again when we actually perform the |
| conversion. */ |
| push_deferring_access_checks (dk_deferred); |
| |
| t = implicit_conversion (to, from, arg, /*c_cast_p=*/false, |
| flags, complain); |
| ok_p = (t && !t->bad_p); |
| |
| /* Discard the access checks now. */ |
| pop_deferring_access_checks (); |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return ok_p; |
| } |
| |
| /* Like can_convert_arg, but allows dubious conversions as well. */ |
| |
| bool |
| can_convert_arg_bad (tree to, tree from, tree arg, int flags, |
| tsubst_flags_t complain) |
| { |
| conversion *t; |
| void *p; |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| /* Try to perform the conversion. */ |
| t = implicit_conversion (to, from, arg, /*c_cast_p=*/false, |
| flags, complain); |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return t != NULL; |
| } |
| |
| /* Convert EXPR to TYPE. Return the converted expression. |
| |
| Note that we allow bad conversions here because by the time we get to |
| this point we are committed to doing the conversion. If we end up |
| doing a bad conversion, convert_like will complain. */ |
| |
| tree |
| perform_implicit_conversion_flags (tree type, tree expr, |
| tsubst_flags_t complain, int flags) |
| { |
| conversion *conv; |
| void *p; |
| location_t loc = cp_expr_loc_or_input_loc (expr); |
| |
| if (TYPE_REF_P (type)) |
| expr = mark_lvalue_use (expr); |
| else |
| expr = mark_rvalue_use (expr); |
| |
| if (error_operand_p (expr)) |
| return error_mark_node; |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| conv = implicit_conversion (type, TREE_TYPE (expr), expr, |
| /*c_cast_p=*/false, |
| flags, complain); |
| |
| if (!conv) |
| { |
| if (complain & tf_error) |
| { |
| /* If expr has unknown type, then it is an overloaded function. |
| Call instantiate_type to get good error messages. */ |
| if (TREE_TYPE (expr) == unknown_type_node) |
| instantiate_type (type, expr, complain); |
| else if (invalid_nonstatic_memfn_p (loc, expr, complain)) |
| /* We gave an error. */; |
| else |
| { |
| range_label_for_type_mismatch label (TREE_TYPE (expr), type); |
| gcc_rich_location rich_loc (loc, &label); |
| error_at (&rich_loc, "could not convert %qE from %qH to %qI", |
| expr, TREE_TYPE (expr), type); |
| } |
| } |
| expr = error_mark_node; |
| } |
| else if (processing_template_decl && conv->kind != ck_identity) |
| { |
| /* In a template, we are only concerned about determining the |
| type of non-dependent expressions, so we do not have to |
| perform the actual conversion. But for initializers, we |
| need to be able to perform it at instantiation |
| (or instantiate_non_dependent_expr) time. */ |
| expr = build1 (IMPLICIT_CONV_EXPR, type, expr); |
| if (!(flags & LOOKUP_ONLYCONVERTING)) |
| IMPLICIT_CONV_EXPR_DIRECT_INIT (expr) = true; |
| if (flags & LOOKUP_NO_NARROWING) |
| IMPLICIT_CONV_EXPR_BRACED_INIT (expr) = true; |
| } |
| else |
| expr = convert_like (conv, expr, complain); |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return expr; |
| } |
| |
| tree |
| perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain) |
| { |
| return perform_implicit_conversion_flags (type, expr, complain, |
| LOOKUP_IMPLICIT); |
| } |
| |
| /* Convert EXPR to TYPE (as a direct-initialization) if that is |
| permitted. If the conversion is valid, the converted expression is |
| returned. Otherwise, NULL_TREE is returned, except in the case |
| that TYPE is a class type; in that case, an error is issued. If |
| C_CAST_P is true, then this direct-initialization is taking |
| place as part of a static_cast being attempted as part of a C-style |
| cast. */ |
| |
| tree |
| perform_direct_initialization_if_possible (tree type, |
| tree expr, |
| bool c_cast_p, |
| tsubst_flags_t complain) |
| { |
| conversion *conv; |
| void *p; |
| |
| if (type == error_mark_node || error_operand_p (expr)) |
| return error_mark_node; |
| /* [dcl.init] |
| |
| If the destination type is a (possibly cv-qualified) class type: |
| |
| -- If the initialization is direct-initialization ..., |
| constructors are considered. |
| |
| -- If overload resolution is successful, the selected constructor |
| is called to initialize the object, with the initializer expression |
| or expression-list as its argument(s). |
| |
| -- Otherwise, if no constructor is viable, the destination type is |
| a (possibly cv-qualified) aggregate class A, and the initializer is |
| a parenthesized expression-list, the object is initialized as |
| follows... */ |
| if (CLASS_TYPE_P (type)) |
| { |
| releasing_vec args (make_tree_vector_single (expr)); |
| expr = build_special_member_call (NULL_TREE, complete_ctor_identifier, |
| &args, type, LOOKUP_NORMAL, complain); |
| return build_cplus_new (type, expr, complain); |
| } |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| conv = implicit_conversion (type, TREE_TYPE (expr), expr, |
| c_cast_p, |
| LOOKUP_NORMAL, complain); |
| if (!conv || conv->bad_p) |
| expr = NULL_TREE; |
| else if (processing_template_decl && conv->kind != ck_identity) |
| { |
| /* In a template, we are only concerned about determining the |
| type of non-dependent expressions, so we do not have to |
| perform the actual conversion. But for initializers, we |
| need to be able to perform it at instantiation |
| (or instantiate_non_dependent_expr) time. */ |
| expr = build1 (IMPLICIT_CONV_EXPR, type, expr); |
| IMPLICIT_CONV_EXPR_DIRECT_INIT (expr) = true; |
| } |
| else |
| expr = convert_like_real (conv, expr, NULL_TREE, 0, |
| /*issue_conversion_warnings=*/false, |
| c_cast_p, |
| complain); |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return expr; |
| } |
| |
| /* When initializing a reference that lasts longer than a full-expression, |
| this special rule applies: |
| |
| [class.temporary] |
| |
| The temporary to which the reference is bound or the temporary |
| that is the complete object to which the reference is bound |
| persists for the lifetime of the reference. |
| |
| The temporaries created during the evaluation of the expression |
| initializing the reference, except the temporary to which the |
| reference is bound, are destroyed at the end of the |
| full-expression in which they are created. |
| |
| In that case, we store the converted expression into a new |
| VAR_DECL in a new scope. |
| |
| However, we want to be careful not to create temporaries when |
| they are not required. For example, given: |
| |
| struct B {}; |
| struct D : public B {}; |
| D f(); |
| const B& b = f(); |
| |
| there is no need to copy the return value from "f"; we can just |
| extend its lifetime. Similarly, given: |
| |
| struct S {}; |
| struct T { operator S(); }; |
| T t; |
| const S& s = t; |
| |
| we can extend the lifetime of the return value of the conversion |
| operator. |
| |
| The next several functions are involved in this lifetime extension. */ |
| |
| /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The |
| reference is being bound to a temporary. Create and return a new |
| VAR_DECL with the indicated TYPE; this variable will store the value to |
| which the reference is bound. */ |
| |
| tree |
| make_temporary_var_for_ref_to_temp (tree decl, tree type) |
| { |
| tree var = create_temporary_var (type); |
| |
| /* Register the variable. */ |
| if (VAR_P (decl) |
| && (TREE_STATIC (decl) || CP_DECL_THREAD_LOCAL_P (decl))) |
| { |
| /* Namespace-scope or local static; give it a mangled name. */ |
| |
| /* If an initializer is visible to multiple translation units, those |
| translation units must agree on the addresses of the |
| temporaries. Therefore the temporaries must be given a consistent name |
| and vague linkage. The mangled name of a temporary is the name of the |
| non-temporary object in whose initializer they appear, prefixed with |
| GR and suffixed with a sequence number mangled using the usual rules |
| for a seq-id. Temporaries are numbered with a pre-order, depth-first, |
| left-to-right walk of the complete initializer. */ |
| copy_linkage (var, decl); |
| |
| tree name = mangle_ref_init_variable (decl); |
| DECL_NAME (var) = name; |
| SET_DECL_ASSEMBLER_NAME (var, name); |
| } |
| else |
| /* Create a new cleanup level if necessary. */ |
| maybe_push_cleanup_level (type); |
| |
| return pushdecl (var); |
| } |
| |
| /* EXPR is the initializer for a variable DECL of reference or |
| std::initializer_list type. Create, push and return a new VAR_DECL |
| for the initializer so that it will live as long as DECL. Any |
| cleanup for the new variable is returned through CLEANUP, and the |
| code to initialize the new variable is returned through INITP. */ |
| |
| static tree |
| set_up_extended_ref_temp (tree decl, tree expr, vec<tree, va_gc> **cleanups, |
| tree *initp, tree *cond_guard) |
| { |
| tree init; |
| tree type; |
| tree var; |
| |
| /* Create the temporary variable. */ |
| type = TREE_TYPE (expr); |
| var = make_temporary_var_for_ref_to_temp (decl, type); |
| layout_decl (var, 0); |
| /* If the rvalue is the result of a function call it will be |
| a TARGET_EXPR. If it is some other construct (such as a |
| member access expression where the underlying object is |
| itself the result of a function call), turn it into a |
| TARGET_EXPR here. It is important that EXPR be a |
| TARGET_EXPR below since otherwise the INIT_EXPR will |
| attempt to make a bitwise copy of EXPR to initialize |
| VAR. */ |
| if (TREE_CODE (expr) != TARGET_EXPR) |
| expr = get_target_expr (expr); |
| |
| if (TREE_CODE (decl) == FIELD_DECL |
| && extra_warnings && !TREE_NO_WARNING (decl)) |
| { |
| warning (OPT_Wextra, "a temporary bound to %qD only persists " |
| "until the constructor exits", decl); |
| TREE_NO_WARNING (decl) = true; |
| } |
| |
| /* Recursively extend temps in this initializer. */ |
| TARGET_EXPR_INITIAL (expr) |
| = extend_ref_init_temps (decl, TARGET_EXPR_INITIAL (expr), cleanups, |
| cond_guard); |
| |
| /* Any reference temp has a non-trivial initializer. */ |
| DECL_NONTRIVIALLY_INITIALIZED_P (var) = true; |
| |
| /* If the initializer is constant, put it in DECL_INITIAL so we get |
| static initialization and use in constant expressions. */ |
| init = maybe_constant_init (expr); |
| /* As in store_init_value. */ |
| init = cp_fully_fold (init); |
| if (TREE_CONSTANT (init)) |
| { |
| if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type)) |
| { |
| /* 5.19 says that a constant expression can include an |
| lvalue-rvalue conversion applied to "a glvalue of literal type |
| that refers to a non-volatile temporary object initialized |
| with a constant expression". Rather than try to communicate |
| that this VAR_DECL is a temporary, just mark it constexpr. */ |
| DECL_DECLARED_CONSTEXPR_P (var) = true; |
| DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true; |
| TREE_CONSTANT (var) = true; |
| TREE_READONLY (var) = true; |
| } |
| DECL_INITIAL (var) = init; |
| init = NULL_TREE; |
| } |
| else |
| /* Create the INIT_EXPR that will initialize the temporary |
| variable. */ |
| init = split_nonconstant_init (var, expr); |
| if (at_function_scope_p ()) |
| { |
| add_decl_expr (var); |
| |
| if (TREE_STATIC (var)) |
| init = add_stmt_to_compound (init, register_dtor_fn (var)); |
| else |
| { |
| tree cleanup = cxx_maybe_build_cleanup (var, tf_warning_or_error); |
| if (cleanup) |
| { |
| if (cond_guard && cleanup != error_mark_node) |
| { |
| if (*cond_guard == NULL_TREE) |
| { |
| *cond_guard = build_local_temp (boolean_type_node); |
| add_decl_expr (*cond_guard); |
| tree set = cp_build_modify_expr (UNKNOWN_LOCATION, |
| *cond_guard, NOP_EXPR, |
| boolean_false_node, |
| tf_warning_or_error); |
| finish_expr_stmt (set); |
| } |
| cleanup = build3 (COND_EXPR, void_type_node, |
| *cond_guard, cleanup, NULL_TREE); |
| } |
| vec_safe_push (*cleanups, cleanup); |
| } |
| } |
| |
| /* We must be careful to destroy the temporary only |
| after its initialization has taken place. If the |
| initialization throws an exception, then the |
| destructor should not be run. We cannot simply |
| transform INIT into something like: |
| |
| (INIT, ({ CLEANUP_STMT; })) |
| |
| because emit_local_var always treats the |
| initializer as a full-expression. Thus, the |
| destructor would run too early; it would run at the |
| end of initializing the reference variable, rather |
| than at the end of the block enclosing the |
| reference variable. |
| |
| The solution is to pass back a cleanup expression |
| which the caller is responsible for attaching to |
| the statement tree. */ |
| } |
| else |
| { |
| rest_of_decl_compilation (var, /*toplev=*/1, at_eof); |
| if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)) |
| { |
| if (CP_DECL_THREAD_LOCAL_P (var)) |
| tls_aggregates = tree_cons (NULL_TREE, var, |
| tls_aggregates); |
| else |
| static_aggregates = tree_cons (NULL_TREE, var, |
| static_aggregates); |
| } |
| else |
| /* Check whether the dtor is callable. */ |
| cxx_maybe_build_cleanup (var, tf_warning_or_error); |
| } |
| /* Avoid -Wunused-variable warning (c++/38958). */ |
| if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type) |
| && VAR_P (decl)) |
| TREE_USED (decl) = DECL_READ_P (decl) = true; |
| |
| *initp = init; |
| return var; |
| } |
| |
| /* Convert EXPR to the indicated reference TYPE, in a way suitable for |
| initializing a variable of that TYPE. */ |
| |
| tree |
| initialize_reference (tree type, tree expr, |
| int flags, tsubst_flags_t complain) |
| { |
| conversion *conv; |
| void *p; |
| location_t loc = cp_expr_loc_or_input_loc (expr); |
| |
| if (type == error_mark_node || error_operand_p (expr)) |
| return error_mark_node; |
| |
| /* Get the high-water mark for the CONVERSION_OBSTACK. */ |
| p = conversion_obstack_alloc (0); |
| |
| conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false, |
| flags, complain); |
| /* If this conversion failed, we're in C++20, and we have something like |
| A& a(b) where A is an aggregate, try again, this time as A& a{b}. */ |
| if ((!conv || conv->bad_p) |
| && (flags & LOOKUP_AGGREGATE_PAREN_INIT)) |
| { |
| tree e = build_constructor_single (init_list_type_node, NULL_TREE, expr); |
| CONSTRUCTOR_IS_DIRECT_INIT (e) = true; |
| CONSTRUCTOR_IS_PAREN_INIT (e) = true; |
| conversion *c = reference_binding (type, TREE_TYPE (e), e, |
| /*c_cast_p=*/false, flags, complain); |
| /* If this worked, use it. */ |
| if (c && !c->bad_p) |
| expr = e, conv = c; |
| } |
| if (!conv || conv->bad_p) |
| { |
| if (complain & tf_error) |
| { |
| if (conv) |
| convert_like (conv, expr, complain); |
| else if (!CP_TYPE_CONST_P (TREE_TYPE (type)) |
| && !TYPE_REF_IS_RVALUE (type) |
| && !lvalue_p (expr)) |
| error_at (loc, "invalid initialization of non-const reference of " |
| "type %qH from an rvalue of type %qI", |
| type, TREE_TYPE (expr)); |
| else |
| error_at (loc, "invalid initialization of reference of type " |
| "%qH from expression of type %qI", type, |
| TREE_TYPE (expr)); |
| } |
| return error_mark_node; |
| } |
| |
| if (conv->kind == ck_ref_bind) |
| /* Perform the conversion. */ |
| expr = convert_like (conv, expr, complain); |
| else if (conv->kind == ck_ambig) |
| /* We gave an error in build_user_type_conversion_1. */ |
| expr = error_mark_node; |
| else |
| gcc_unreachable (); |
| |
| /* Free all the conversions we allocated. */ |
| obstack_free (&conversion_obstack, p); |
| |
| return expr; |
| } |
| |
| /* If *P is an xvalue expression, prevent temporary lifetime extension if it |
| gets used to initialize a reference. */ |
| |
| static tree |
| prevent_lifetime_extension (tree t) |
| { |
| tree *p = &t; |
| while (TREE_CODE (*p) == COMPOUND_EXPR) |
| p = &TREE_OPERAND (*p, 1); |
| while (handled_component_p (*p)) |
| p = &TREE_OPERAND (*p, 0); |
| /* Change a TARGET_EXPR from prvalue to xvalue. */ |
| if (TREE_CODE (*p) == TARGET_EXPR) |
| *p = build2 (COMPOUND_EXPR, TREE_TYPE (*p), *p, |
| move (TARGET_EXPR_SLOT (*p))); |
| return t; |
| } |
| |
| /* Subroutine of extend_ref_init_temps. Possibly extend one initializer, |
| which is bound either to a reference or a std::initializer_list. */ |
| |
| static tree |
| extend_ref_init_temps_1 (tree decl, tree init, vec<tree, va_gc> **cleanups, |
| tree *cond_guard) |
| { |
| tree sub = init; |
| tree *p; |
| STRIP_NOPS (sub); |
| if (TREE_CODE (sub) == COMPOUND_EXPR) |
| { |
| TREE_OPERAND (sub, 1) |
| = extend_ref_init_temps_1 (decl, TREE_OPERAND (sub, 1), cleanups, |
| cond_guard); |
| return init; |
| } |
| if (TREE_CODE (sub) == COND_EXPR) |
| { |
| tree cur_cond_guard = NULL_TREE; |
| if (TREE_OPERAND (sub, 1)) |
| TREE_OPERAND (sub, 1) |
| = extend_ref_init_temps_1 (decl, TREE_OPERAND (sub, 1), cleanups, |
| &cur_cond_guard); |
| if (cur_cond_guard) |
| { |
| tree set = cp_build_modify_expr (UNKNOWN_LOCATION, cur_cond_guard, |
| NOP_EXPR, boolean_true_node, |
| tf_warning_or_error); |
| TREE_OPERAND (sub, 1) |
| = cp_build_compound_expr (set, TREE_OPERAND (sub, 1), |
| tf_warning_or_error); |
| } |
| cur_cond_guard = NULL_TREE; |
| if (TREE_OPERAND (sub, 2)) |
| TREE_OPERAND (sub, 2) |
| = extend_ref_init_temps_1 (decl, TREE_OPERAND (sub, 2), cleanups, |
| &cur_cond_guard); |
| if (cur_cond_guard) |
| { |
| tree set = cp_build_modify_expr (UNKNOWN_LOCATION, cur_cond_guard, |
| NOP_EXPR, boolean_true_node, |
| tf_warning_or_error); |
| TREE_OPERAND (sub, 2) |
| = cp_build_compound_expr (set, TREE_OPERAND (sub, 2), |
| tf_warning_or_error); |
| } |
| return init; |
| } |
| if (TREE_CODE (sub) != ADDR_EXPR) |
| return init; |
| /* Deal with binding to a subobject. */ |
| for (p = &TREE_OPERAND (sub, 0); |
| TREE_CODE (*p) == COMPONENT_REF || TREE_CODE (*p) == ARRAY_REF; ) |
| p = &TREE_OPERAND (*p, 0); |
| if (TREE_CODE (*p) == TARGET_EXPR) |
| { |
| tree subinit = NULL_TREE; |
| *p = set_up_extended_ref_temp (decl, *p, cleanups, &subinit, cond_guard); |
| recompute_tree_invariant_for_addr_expr (sub); |
| if (init != sub) |
| init = fold_convert (TREE_TYPE (init), sub); |
| if (subinit) |
| init = build2 (COMPOUND_EXPR, TREE_TYPE (init), subinit, init); |
| } |
| return init; |
| } |
| |
| /* INIT is part of the initializer for DECL. If there are any |
| reference or initializer lists being initialized, extend their |
| lifetime to match that of DECL. */ |
| |
| tree |
| extend_ref_init_temps (tree decl, tree init, vec<tree, va_gc> **cleanups, |
| tree *cond_guard) |
| { |
| tree type = TREE_TYPE (init); |
| if (processing_template_decl) |
| return init; |
| if (TYPE_REF_P (type)) |
| init = extend_ref_init_temps_1 (decl, init, cleanups, cond_guard); |
| else |
| { |
| tree ctor = init; |
| if (TREE_CODE (ctor) == TARGET_EXPR) |
| ctor = TARGET_EXPR_INITIAL (ctor); |
| if (TREE_CODE (ctor) == CONSTRUCTOR) |
| { |
| /* [dcl.init] When initializing an aggregate from a parenthesized list |
| of values... a temporary object bound to a reference does not have |
| its lifetime extended. */ |
| if (CONSTRUCTOR_IS_PAREN_INIT (ctor)) |
| return init; |
| |
| if (is_std_init_list (type)) |
| { |
| /* The temporary array underlying a std::initializer_list |
| is handled like a reference temporary. */ |
| tree array = CONSTRUCTOR_ELT (ctor, 0)->value; |
| array = extend_ref_init_temps_1 (decl, array, cleanups, |
| cond_guard); |
| CONSTRUCTOR_ELT (ctor, 0)->value = array; |
| } |
| else |
| { |
| unsigned i; |
| constructor_elt *p; |
| vec<constructor_elt, va_gc> *elts = CONSTRUCTOR_ELTS (ctor); |
| FOR_EACH_VEC_SAFE_ELT (elts, i, p) |
| p->value = extend_ref_init_temps (decl, p->value, cleanups, |
| cond_guard); |
| } |
| recompute_constructor_flags (ctor); |
| if (decl_maybe_constant_var_p (decl) && TREE_CONSTANT (ctor)) |
| DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = true; |
| } |
| } |
| |
| return init; |
| } |
| |
| /* Returns true iff an initializer for TYPE could contain temporaries that |
| need to be extended because they are bound to references or |
| std::initializer_list. */ |
| |
| bool |
| type_has_extended_temps (tree type) |
| { |
| type = strip_array_types (type); |
| if (TYPE_REF_P (type)) |
| return true; |
| if (CLASS_TYPE_P (type)) |
| { |
| if (is_std_init_list (type)) |
| return true; |
| for (tree f = next_initializable_field (TYPE_FIELDS (type)); |
| f; f = next_initializable_field (DECL_CHAIN (f))) |
| if (type_has_extended_temps (TREE_TYPE (f))) |
| return true; |
| } |
| return false; |
| } |
| |
| /* Returns true iff TYPE is some variant of std::initializer_list. */ |
| |
| bool |
| is_std_init_list (tree type) |
| { |
| if (!TYPE_P (type)) |
| return false; |
| if (cxx_dialect == cxx98) |
| return false; |
| /* Look through typedefs. */ |
| type = TYPE_MAIN_VARIANT (type); |
| return (CLASS_TYPE_P (type) |
| && CP_TYPE_CONTEXT (type) == std_node |
| && init_list_identifier == DECL_NAME (TYPE_NAME (type))); |
| } |
| |
| /* Returns true iff DECL is a list constructor: i.e. a constructor which |
| will accept an argument list of a single std::initializer_list<T>. */ |
| |
| bool |
| is_list_ctor (tree decl) |
| { |
| tree args = FUNCTION_FIRST_USER_PARMTYPE (decl); |
| tree arg; |
| |
| if (!args || args == void_list_node) |
| return false; |
| |
| arg = non_reference (TREE_VALUE (args)); |
| if (!is_std_init_list (arg)) |
| return false; |
| |
| args = TREE_CHAIN (args); |
| |
| if (args && args != void_list_node && !TREE_PURPOSE (args)) |
| /* There are more non-defaulted parms. */ |
| return false; |
| |
| return true; |
| } |
| |
| #include "gt-cp-call.h" |