blob: c4a09baa2339c2bea847e870d03bfaffd9e38270 [file] [log] [blame]
/* Functions related to invoking methods and overloaded functions.
Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
1999, 2000, 2001, 2002, 2003, 2004 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 2, 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 COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* High-level class interface. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "cp-tree.h"
#include "output.h"
#include "flags.h"
#include "rtl.h"
#include "toplev.h"
#include "expr.h"
#include "diagnostic.h"
#include "intl.h"
#include "target.h"
#include "convert.h"
static struct z_candidate * tourney (struct z_candidate *);
static int equal_functions (tree, tree);
static int joust (struct z_candidate *, struct z_candidate *, bool);
static int compare_ics (tree, tree);
static tree build_over_call (struct z_candidate *, int);
static tree build_java_interface_fn_ref (tree, tree);
#define convert_like(CONV, EXPR) \
convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
/*issue_conversion_warnings=*/true)
#define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
/*issue_conversion_warnings=*/true)
static tree convert_like_real (tree, tree, tree, int, int, bool);
static void op_error (enum tree_code, enum tree_code, tree, tree,
tree, const char *);
static tree build_object_call (tree, tree);
static tree resolve_args (tree);
static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
static void print_z_candidate (const char *, struct z_candidate *);
static void print_z_candidates (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, tree,
tree, tree, int, unification_kind_t);
static struct z_candidate *add_template_candidate_real
(struct z_candidate **, tree, tree, tree, tree, tree,
tree, tree, int, tree, unification_kind_t);
static struct z_candidate *add_template_conv_candidate
(struct z_candidate **, tree, tree, tree, tree, tree, tree);
static void add_builtin_candidates
(struct z_candidate **, enum tree_code, enum tree_code,
tree, tree *, int);
static void add_builtin_candidate
(struct z_candidate **, enum tree_code, enum tree_code,
tree, tree, tree, tree *, tree *, int);
static bool is_complete (tree);
static void build_builtin_candidate
(struct z_candidate **, tree, tree, tree, tree *, tree *,
int);
static struct z_candidate *add_conv_candidate
(struct z_candidate **, tree, tree, tree, tree, tree);
static struct z_candidate *add_function_candidate
(struct z_candidate **, tree, tree, tree, tree, tree, int);
static tree implicit_conversion (tree, tree, tree, int);
static tree standard_conversion (tree, tree, tree);
static tree reference_binding (tree, tree, tree, int);
static tree build_conv (enum tree_code, tree, tree);
static bool is_subseq (tree, tree);
static tree maybe_handle_ref_bind (tree *);
static void maybe_handle_implicit_object (tree *);
static struct z_candidate *add_candidate
(struct z_candidate **, tree, tree, tree, tree, tree, int);
static tree source_type (tree);
static void add_warning (struct z_candidate *, struct z_candidate *);
static bool reference_related_p (tree, tree);
static bool reference_compatible_p (tree, tree);
static tree convert_class_to_reference (tree, tree, tree);
static tree direct_reference_binding (tree, tree);
static bool promoted_arithmetic_type_p (tree);
static tree conditional_conversion (tree, tree);
static char *name_as_c_string (tree, tree, bool *);
static tree call_builtin_trap (void);
static tree prep_operand (tree);
static void add_candidates (tree, tree, tree, bool, tree, tree,
int, struct z_candidate **);
static tree merge_conversion_sequences (tree, tree);
static bool magic_varargs_p (tree);
static tree build_temp (tree, tree, int, void (**)(const char *, ...));
static void check_constructor_callable (tree, tree);
tree
build_vfield_ref (tree datum, tree type)
{
if (datum == error_mark_node)
return error_mark_node;
if (TREE_CODE (TREE_TYPE (datum)) == REFERENCE_TYPE)
datum = convert_from_reference (datum);
if (TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
&& !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
datum = convert_to_base (datum, type, /*check_access=*/false);
return build (COMPONENT_REF, TREE_TYPE (TYPE_VFIELD (type)),
datum, TYPE_VFIELD (type));
}
/* Returns nonzero iff the destructor name specified in NAME
(a BIT_NOT_EXPR) matches BASETYPE. The operand of NAME can take many
forms... */
bool
check_dtor_name (tree basetype, tree name)
{
name = TREE_OPERAND (name, 0);
/* 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 (TREE_CODE (name) == IDENTIFIER_NODE)
{
if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
|| (TREE_CODE (basetype) == ENUMERAL_TYPE
&& name == TYPE_IDENTIFIER (basetype)))
name = basetype;
else
name = get_type_value (name);
}
/* In the case of:
template <class T> struct S { ~S(); };
int i;
i.~S();
NAME will be a class template. */
else if (DECL_CLASS_TEMPLATE_P (name))
return false;
else
abort ();
if (name && TYPE_MAIN_VARIANT (basetype) == TYPE_MAIN_VARIANT (name))
return true;
return false;
}
/* We want the address of a function or method. We avoid creating a
pointer-to-member function. */
tree
build_addr_func (tree function)
{
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));
}
function = build_address (function);
}
else
function = decay_conversion (function);
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. */
tree
build_call (tree function, tree parms)
{
int is_constructor = 0;
int nothrow;
tree tmp;
tree decl;
tree result_type;
tree fntype;
function = build_addr_func (function);
if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
{
sorry ("unable to call pointer to member function here");
return error_mark_node;
}
fntype = TREE_TYPE (TREE_TYPE (function));
result_type = TREE_TYPE (fntype);
if (TREE_CODE (function) == ADDR_EXPR
&& TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
decl = TREE_OPERAND (function, 0);
else
decl = NULL_TREE;
/* We check both the decl and the type; a function may be known not to
throw without being declared throw(). */
nothrow = ((decl && TREE_NOTHROW (decl))
|| TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
if (decl && TREE_THIS_VOLATILE (decl) && cfun)
current_function_returns_abnormally = 1;
if (decl && TREE_DEPRECATED (decl))
warn_deprecated_use (decl);
require_complete_eh_spec_types (fntype, decl);
if (decl && DECL_CONSTRUCTOR_P (decl))
is_constructor = 1;
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. */
if (DECL_ARTIFICIAL (decl)
|| !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)), "__", 2))
mark_used (decl);
else
abort ();
}
/* 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 || ! DECL_BUILT_IN (decl))
for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
&& ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
{
tree t = build (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
TREE_VALUE (tmp) = build (COMPOUND_EXPR, TREE_TYPE (t),
TREE_VALUE (tmp), t);
}
function = build (CALL_EXPR, result_type, function, parms);
TREE_HAS_CONSTRUCTOR (function) = is_constructor;
TREE_NOTHROW (function) = nothrow;
return function;
}
/* Build something of the form ptr->method (args)
or object.method (args). This can also build
calls to constructors, and find friends.
Member functions always take their class variable
as a pointer.
INSTANCE is a class instance.
NAME is the name of the method desired, usually an IDENTIFIER_NODE.
PARMS help to figure out what that NAME really refers to.
BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
down to the real instance type to use for access checking. We need this
information to get protected accesses correct.
FLAGS is the logical disjunction of zero or more LOOKUP_
flags. See cp-tree.h for more info.
If this is all OK, calls build_function_call with the resolved
member function.
This function must also handle being called to perform
initialization, promotion/coercion of arguments, and
instantiation of default parameters.
Note that NAME may refer to an instance variable name. If
`operator()()' is defined for the type of that field, then we return
that result. */
/* New overloading code. */
struct z_candidate GTY(()) {
/* The FUNCTION_DECL that will be called if this candidate is
selected by overload resolution. */
tree fn;
/* The arguments to use when calling this function. */
tree args;
/* The implicit conversion sequences for each of the arguments to
FN. */
tree convs;
/* If FN is a user-defined conversion, the standard conversion
sequence from the type returned by FN to the desired destination
type. */
tree second_conv;
int viable;
/* 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 the by
the `this' pointer must correspond to the most derived class
indicated by the CONVERSION_PATH. */
tree conversion_path;
tree template;
tree warnings;
struct z_candidate *next;
};
#define IDENTITY_RANK 0
#define EXACT_RANK 1
#define PROMO_RANK 2
#define STD_RANK 3
#define PBOOL_RANK 4
#define USER_RANK 5
#define ELLIPSIS_RANK 6
#define BAD_RANK 7
#define ICS_RANK(NODE) \
(ICS_BAD_FLAG (NODE) ? BAD_RANK \
: ICS_ELLIPSIS_FLAG (NODE) ? ELLIPSIS_RANK \
: ICS_USER_FLAG (NODE) ? USER_RANK \
: ICS_STD_RANK (NODE))
#define ICS_STD_RANK(NODE) TREE_COMPLEXITY (NODE)
#define ICS_USER_FLAG(NODE) TREE_LANG_FLAG_0 (NODE)
#define ICS_ELLIPSIS_FLAG(NODE) TREE_LANG_FLAG_1 (NODE)
#define ICS_THIS_FLAG(NODE) TREE_LANG_FLAG_2 (NODE)
#define ICS_BAD_FLAG(NODE) TREE_LANG_FLAG_3 (NODE)
/* In a REF_BIND or a BASE_CONV, this indicates that a temporary
should be created to hold the result of the conversion. */
#define NEED_TEMPORARY_P(NODE) TREE_LANG_FLAG_4 (NODE)
/* TRUE in an IDENTITY_CONV or BASE_CONV if the copy constructor must
be accessible, even though it is not being used. */
#define CHECK_COPY_CONSTRUCTOR_P(NODE) TREE_LANG_FLAG_5 (NODE)
#define USER_CONV_CAND(NODE) WRAPPER_ZC (TREE_OPERAND (NODE, 1))
#define USER_CONV_FN(NODE) (USER_CONV_CAND (NODE)->fn)
/* Returns true iff T is a null pointer constant in the sense of
[conv.ptr]. */
bool
null_ptr_cst_p (tree t)
{
/* [conv.ptr]
A null pointer constant is an integral constant expression
(_expr.const_) rvalue of integer type that evaluates to zero. */
if (DECL_INTEGRAL_CONSTANT_VAR_P (t))
t = decl_constant_value (t);
if (t == null_node
|| (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
return true;
return false;
}
/* Returns nonzero if PARMLIST consists of only default parms and/or
ellipsis. */
bool
sufficient_parms_p (tree parmlist)
{
for (; parmlist && parmlist != void_list_node;
parmlist = TREE_CHAIN (parmlist))
if (!TREE_PURPOSE (parmlist))
return false;
return true;
}
static tree
build_conv (enum tree_code code, tree type, tree from)
{
tree t;
int rank = ICS_STD_RANK (from);
/* We can't use buildl1 here because CODE could be USER_CONV, which
takes two arguments. In that case, the caller is responsible for
filling in the second argument. */
t = make_node (code);
TREE_TYPE (t) = type;
TREE_OPERAND (t, 0) = from;
switch (code)
{
case PTR_CONV:
case PMEM_CONV:
case BASE_CONV:
case STD_CONV:
if (rank < STD_RANK)
rank = STD_RANK;
break;
case QUAL_CONV:
if (rank < EXACT_RANK)
rank = EXACT_RANK;
default:
break;
}
ICS_STD_RANK (t) = rank;
ICS_USER_FLAG (t) = (code == USER_CONV || ICS_USER_FLAG (from));
ICS_BAD_FLAG (t) = ICS_BAD_FLAG (from);
return t;
}
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. */
static tree
standard_conversion (tree to, tree from, tree expr)
{
enum tree_code fcode, tcode;
tree conv;
bool fromref = false;
to = non_reference (to);
if (TREE_CODE (from) == REFERENCE_TYPE)
{
fromref = true;
from = TREE_TYPE (from);
}
to = strip_top_quals (to);
from = strip_top_quals (from);
if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
&& expr && type_unknown_p (expr))
{
expr = instantiate_type (to, expr, tf_conv);
if (expr == error_mark_node)
return NULL_TREE;
from = TREE_TYPE (expr);
}
fcode = TREE_CODE (from);
tcode = TREE_CODE (to);
conv = build1 (IDENTITY_CONV, from, expr);
if (fcode == FUNCTION_TYPE)
{
from = build_pointer_type (from);
fcode = TREE_CODE (from);
conv = build_conv (LVALUE_CONV, from, conv);
}
else if (fcode == ARRAY_TYPE)
{
from = build_pointer_type (TREE_TYPE (from));
fcode = TREE_CODE (from);
conv = build_conv (LVALUE_CONV, from, conv);
}
else if (fromref || (expr && lvalue_p (expr)))
conv = build_conv (RVALUE_CONV, from, conv);
/* 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. */
tree part_conv = standard_conversion
(TREE_TYPE (to), TREE_TYPE (from), NULL_TREE);
if (part_conv)
{
conv = build_conv (TREE_CODE (part_conv), to, conv);
ICS_STD_RANK (conv) = ICS_STD_RANK (part_conv);
}
else
conv = NULL_TREE;
return conv;
}
if (same_type_p (from, to))
return conv;
if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
&& expr && null_ptr_cst_p (expr))
conv = build_conv (STD_CONV, to, conv);
else if (tcode == POINTER_TYPE && fcode == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (to)) == VECTOR_TYPE
&& TREE_CODE (TREE_TYPE (from)) == VECTOR_TYPE
&& ((*targetm.vector_opaque_p) (TREE_TYPE (to))
|| (*targetm.vector_opaque_p) (TREE_TYPE (from))))
conv = build_conv (STD_CONV, 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 (STD_CONV, to, conv);
ICS_BAD_FLAG (conv) = 1;
}
else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
{
/* For backwards brain damage compatibility, allow interconversion of
enums and integers with a pedwarn. */
conv = build_conv (STD_CONV, to, conv);
ICS_BAD_FLAG (conv) = 1;
}
else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
|| (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
{
tree to_pointee;
tree from_pointee;
if (tcode == POINTER_TYPE
&& same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
TREE_TYPE (to)))
;
else if (VOID_TYPE_P (TREE_TYPE (to))
&& !TYPE_PTRMEM_P (from)
&& TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
{
from = build_pointer_type
(cp_build_qualified_type (void_type_node,
cp_type_quals (TREE_TYPE (from))));
conv = build_conv (PTR_CONV, from, conv);
}
else if (TYPE_PTRMEM_P (from))
{
tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
if (DERIVED_FROM_P (fbase, tbase)
&& (same_type_ignoring_top_level_qualifiers_p
(TYPE_PTRMEM_POINTED_TO_TYPE (from),
TYPE_PTRMEM_POINTED_TO_TYPE (to))))
{
from = build_ptrmem_type (tbase,
TYPE_PTRMEM_POINTED_TO_TYPE (from));
conv = build_conv (PMEM_CONV, from, conv);
}
else if (!same_type_p (fbase, tbase))
return NULL;
}
else if (IS_AGGR_TYPE (TREE_TYPE (from))
&& IS_AGGR_TYPE (TREE_TYPE (to))
/* [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 not
ACESSIBLY_UNIQUELY_DERIVED_FROM_P, in this test. */
&& DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
{
from =
cp_build_qualified_type (TREE_TYPE (to),
cp_type_quals (TREE_TYPE (from)));
from = build_pointer_type (from);
conv = build_conv (PTR_CONV, from, conv);
}
if (tcode == POINTER_TYPE)
{
to_pointee = TREE_TYPE (to);
from_pointee = TREE_TYPE (from);
}
else
{
to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
}
if (same_type_p (from, to))
/* OK */;
else if (comp_ptr_ttypes (to_pointee, from_pointee))
conv = build_conv (QUAL_CONV, to, conv);
else if (expr && string_conv_p (to, expr, 0))
/* converting from string constant to char *. */
conv = build_conv (QUAL_CONV, to, conv);
else if (ptr_reasonably_similar (to_pointee, from_pointee))
{
conv = build_conv (PTR_CONV, to, conv);
ICS_BAD_FLAG (conv) = 1;
}
else
return 0;
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 = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
if (!DERIVED_FROM_P (fbase, tbase)
|| !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
|| !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
|| cp_type_quals (fbase) != cp_type_quals (tbase))
return 0;
from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
from = build_method_type_directly (from,
TREE_TYPE (fromfn),
TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
from = build_ptrmemfunc_type (build_pointer_type (from));
conv = build_conv (PMEM_CONV, from, conv);
}
else if (tcode == BOOLEAN_TYPE)
{
/* [conv.bool]
An rvalue of arithmetic, enumeration, pointer, or pointer to
member type can be converted to an rvalue of type bool. */
if (ARITHMETIC_TYPE_P (from)
|| fcode == ENUMERAL_TYPE
|| fcode == POINTER_TYPE
|| TYPE_PTR_TO_MEMBER_P (from))
{
conv = build_conv (STD_CONV, to, conv);
if (fcode == POINTER_TYPE
|| TYPE_PTRMEM_P (from)
|| (TYPE_PTRMEMFUNC_P (from)
&& ICS_STD_RANK (conv) < PBOOL_RANK))
ICS_STD_RANK (conv) = PBOOL_RANK;
return conv;
}
return NULL_TREE;
}
/* We don't check for ENUMERAL_TYPE here because there are no standard
conversions to enum type. */
else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
|| tcode == REAL_TYPE)
{
if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
return 0;
conv = build_conv (STD_CONV, to, conv);
/* Give this a better rank if it's a promotion. */
if (same_type_p (to, type_promotes_to (from))
&& ICS_STD_RANK (TREE_OPERAND (conv, 0)) <= PROMO_RANK)
ICS_STD_RANK (conv) = PROMO_RANK;
}
else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
&& ((*targetm.vector_opaque_p) (from)
|| (*targetm.vector_opaque_p) (to)))
return build_conv (STD_CONV, to, conv);
else if (IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
&& is_properly_derived_from (from, to))
{
if (TREE_CODE (conv) == RVALUE_CONV)
conv = TREE_OPERAND (conv, 0);
conv = build_conv (BASE_CONV, 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. */
NEED_TEMPORARY_P (conv) = 1;
}
else
return 0;
return conv;
}
/* Returns nonzero if T1 is reference-related to T2. */
static bool
reference_related_p (tree t1, tree t2)
{
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 the same type as T2, or T1 is a base class
of T2. */
return (same_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. */
static bool
reference_compatible_p (tree t1, tree t2)
{
/* [dcl.init.ref]
"cv1 T1" is reference compatible with "cv2 T2" if T1 is
reference-related to T2 and cv1 is the same cv-qualification as,
or greater cv-qualification than, cv2. */
return (reference_related_p (t1, t2)
&& at_least_as_qualified_p (t1, t2));
}
/* Determine whether or not the EXPR (of class type S) can be
converted to T as in [over.match.ref]. */
static tree
convert_class_to_reference (tree t, tree s, tree expr)
{
tree conversions;
tree arglist;
tree conv;
tree reference_type;
struct z_candidate *candidates;
struct z_candidate *cand;
bool any_viable_p;
conversions = lookup_conversions (s);
if (!conversions)
return NULL_TREE;
/* [over.match.ref]
Assuming that "cv1 T" is the underlying type of the reference
being initialized, and "cv S" is the type of the initializer
expression, with S a class type, the candidate functions are
selected as follows:
--The conversion functions of S and its base classes are
considered. Those that are not hidden within S and yield type
"reference to cv2 T2", where "cv1 T" is reference-compatible
(_dcl.init.ref_) with "cv2 T2", are candidate functions.
The argument list has one argument, which is the initializer
expression. */
candidates = 0;
/* Conceptually, we should take the address of EXPR and put it in
the argument list. Unfortunately, however, that can result in
error messages, which we should not issue now because we are just
trying to find a conversion operator. Therefore, we use NULL,
cast to the appropriate type. */
arglist = build_int_2 (0, 0);
TREE_TYPE (arglist) = build_pointer_type (s);
arglist = build_tree_list (NULL_TREE, arglist);
reference_type = build_reference_type (t);
while (conversions)
{
tree fns = TREE_VALUE (conversions);
for (; fns; fns = OVL_NEXT (fns))
{
tree f = OVL_CURRENT (fns);
tree t2 = TREE_TYPE (TREE_TYPE (f));
cand = NULL;
/* If this is a template function, try to get an exact
match. */
if (TREE_CODE (f) == TEMPLATE_DECL)
{
cand = add_template_candidate (&candidates,
f, s,
NULL_TREE,
arglist,
reference_type,
TYPE_BINFO (s),
TREE_PURPOSE (conversions),
LOOKUP_NORMAL,
DEDUCE_CONV);
if (cand)
{
/* Now, see if the conversion function really returns
an lvalue of the appropriate type. From the
point of view of unification, simply returning an
rvalue of the right type is good enough. */
f = cand->fn;
t2 = TREE_TYPE (TREE_TYPE (f));
if (TREE_CODE (t2) != REFERENCE_TYPE
|| !reference_compatible_p (t, TREE_TYPE (t2)))
{
candidates = candidates->next;
cand = NULL;
}
}
}
else if (TREE_CODE (t2) == REFERENCE_TYPE
&& reference_compatible_p (t, TREE_TYPE (t2)))
cand = add_function_candidate (&candidates, f, s, arglist,
TYPE_BINFO (s),
TREE_PURPOSE (conversions),
LOOKUP_NORMAL);
if (cand)
{
/* Build a standard conversion sequence indicating the
binding from the reference type returned by the
function to the desired REFERENCE_TYPE. */
cand->second_conv
= (direct_reference_binding
(reference_type,
build1 (IDENTITY_CONV,
TREE_TYPE (TREE_TYPE (TREE_TYPE (cand->fn))),
NULL_TREE)));
ICS_BAD_FLAG (cand->second_conv)
|= ICS_BAD_FLAG (TREE_VEC_ELT (cand->convs, 0));
}
}
conversions = TREE_CHAIN (conversions);
}
candidates = splice_viable (candidates, pedantic, &any_viable_p);
/* If none of the conversion functions worked out, let our caller
know. */
if (!any_viable_p)
return NULL_TREE;
cand = tourney (candidates);
if (!cand)
return NULL_TREE;
/* Now that we know that this is the function we're going to use fix
the dummy first argument. */
cand->args = tree_cons (NULL_TREE,
build_this (expr),
TREE_CHAIN (cand->args));
/* Build a user-defined conversion sequence representing the
conversion. */
conv = build_conv (USER_CONV,
TREE_TYPE (TREE_TYPE (cand->fn)),
build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
TREE_OPERAND (conv, 1) = build_zc_wrapper (cand);
/* Merge it with the standard conversion sequence from the
conversion function's return type to the desired type. */
cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
if (cand->viable == -1)
ICS_BAD_FLAG (conv) = 1;
return cand->second_conv;
}
/* 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 tree
direct_reference_binding (tree type, tree conv)
{
tree t;
my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 20030306);
my_friendly_assert (TREE_CODE (TREE_TYPE (conv)) != REFERENCE_TYPE,
20030306);
t = TREE_TYPE (type);
/* [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 (!same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (conv)))
{
/* Represent the derived-to-base conversion. */
conv = build_conv (BASE_CONV, 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. */
NEED_TEMPORARY_P (conv) = 0;
}
return build_conv (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. */
static tree
reference_binding (tree rto, tree rfrom, tree expr, int flags)
{
tree conv = NULL_TREE;
tree to = TREE_TYPE (rto);
tree from = rfrom;
bool related_p;
bool compatible_p;
cp_lvalue_kind lvalue_p = clk_none;
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_TREE;
from = TREE_TYPE (expr);
}
if (TREE_CODE (from) == REFERENCE_TYPE)
{
/* Anything with reference type is an lvalue. */
lvalue_p = clk_ordinary;
from = TREE_TYPE (from);
}
else if (expr)
lvalue_p = real_lvalue_p (expr);
/* Figure out whether or not the types are reference-related and
reference compatible. We have do do this after stripping
references from FROM. */
related_p = reference_related_p (to, from);
compatible_p = reference_compatible_p (to, from);
if (lvalue_p && compatible_p)
{
/* [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. */
conv = build1 (IDENTITY_CONV, from, expr);
conv = direct_reference_binding (rto, conv);
if ((lvalue_p & clk_bitfield) != 0
|| ((lvalue_p & 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. */
NEED_TEMPORARY_P (conv) = 1;
return conv;
}
else if (CLASS_TYPE_P (from) && !(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. */
conv = convert_class_to_reference (to, from, expr);
if (conv)
return 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_TREE;
/* [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 to a non-volatile const type. */
if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
return NULL_TREE;
/* [dcl.init.ref]
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 in one of the following ways:
-- The reference is bound to the object represented by the rvalue
or to a sub-object within that object.
-- ...
We use the first alternative. The implicit conversion sequence
is supposed to be same as we would obtain by generating a
temporary. Fortunately, if the types are reference compatible,
then this is either an identity conversion or the derived-to-base
conversion, just as for direct binding. */
if (CLASS_TYPE_P (from) && compatible_p)
{
conv = build1 (IDENTITY_CONV, from, expr);
conv = direct_reference_binding (rto, conv);
if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE))
CHECK_COPY_CONSTRUCTOR_P (TREE_OPERAND (conv, 0)) = 1;
return conv;
}
/* [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))
return NULL_TREE;
conv = implicit_conversion (to, from, expr, flags);
if (!conv)
return NULL_TREE;
conv = build_conv (REF_BIND, rto, conv);
/* This reference binding, unlike those above, requires the
creation of a temporary. */
NEED_TEMPORARY_P (conv) = 1;
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. Only LOOKUP_NO_CONVERSION is
significant. */
static tree
implicit_conversion (tree to, tree from, tree expr, int flags)
{
tree conv;
if (from == error_mark_node || to == error_mark_node
|| expr == error_mark_node)
return NULL_TREE;
if (TREE_CODE (to) == REFERENCE_TYPE)
conv = reference_binding (to, from, expr, flags);
else
conv = standard_conversion (to, from, expr);
if (conv)
return conv;
if (expr != NULL_TREE
&& (IS_AGGR_TYPE (from)
|| IS_AGGR_TYPE (to))
&& (flags & LOOKUP_NO_CONVERSION) == 0)
{
struct z_candidate *cand;
cand = build_user_type_conversion_1
(to, expr, LOOKUP_ONLYCONVERTING);
if (cand)
conv = cand->second_conv;
/* We used to try to bind a reference to a temporary here, but that
is now handled by the recursive call to this function at the end
of reference_binding. */
return conv;
}
return NULL_TREE;
}
/* Add a new entry to the list of candidates. Used by the add_*_candidate
functions. */
static struct z_candidate *
add_candidate (struct z_candidate **candidates,
tree fn, tree args, tree convs, tree access_path,
tree conversion_path, int viable)
{
struct z_candidate *cand = ggc_alloc_cleared (sizeof (struct z_candidate));
cand->fn = fn;
cand->args = args;
cand->convs = convs;
cand->access_path = access_path;
cand->conversion_path = conversion_path;
cand->viable = viable;
cand->next = *candidates;
*candidates = cand;
return cand;
}
/* Create an overload candidate for the function or method FN called with
the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
to implicit_conversion.
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 arglist,
tree access_path, tree conversion_path,
int flags)
{
tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
int i, len;
tree convs;
tree parmnode, argnode;
tree orig_arglist;
int viable = 1;
/* Built-in functions that haven't been declared don't really
exist. */
if (DECL_ANTICIPATED (fn))
return NULL;
/* The `this', `in_chrg' and VTT arguments to constructors are not
considered in overload resolution. */
if (DECL_CONSTRUCTOR_P (fn))
{
parmlist = skip_artificial_parms_for (fn, parmlist);
orig_arglist = arglist;
arglist = skip_artificial_parms_for (fn, arglist);
}
else
orig_arglist = arglist;
len = list_length (arglist);
convs = make_tree_vec (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)
viable = 0;
/* Make sure there are default args for the rest of the parms. */
else if (!sufficient_parms_p (parmnode))
viable = 0;
if (! viable)
goto out;
/* Second, 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;
argnode = arglist;
for (i = 0; i < len; ++i)
{
tree arg = TREE_VALUE (argnode);
tree argtype = lvalue_type (arg);
tree t;
int is_this;
if (parmnode == void_list_node)
break;
is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
&& ! DECL_CONSTRUCTOR_P (fn));
if (parmnode)
{
tree parmtype = TREE_VALUE (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
= build_qualified_type (ctype,
TYPE_QUALS (TREE_TYPE (parmtype)));
parmtype = build_pointer_type (parmtype);
}
t = implicit_conversion (parmtype, argtype, arg, flags);
}
else
{
t = build1 (IDENTITY_CONV, argtype, arg);
ICS_ELLIPSIS_FLAG (t) = 1;
}
if (t && is_this)
ICS_THIS_FLAG (t) = 1;
TREE_VEC_ELT (convs, i) = t;
if (! t)
{
viable = 0;
break;
}
if (ICS_BAD_FLAG (t))
viable = -1;
if (parmnode)
parmnode = TREE_CHAIN (parmnode);
argnode = TREE_CHAIN (argnode);
}
out:
return add_candidate (candidates, fn, orig_arglist, convs, access_path,
conversion_path, viable);
}
/* 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 ARGLIST, and add it to
CANDIDATES. 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,
tree arglist, tree access_path, tree conversion_path)
{
tree totype = TREE_TYPE (TREE_TYPE (fn));
int i, len, viable, flags;
tree parmlist, convs, parmnode, argnode;
for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
parmlist = TREE_TYPE (parmlist);
parmlist = TYPE_ARG_TYPES (parmlist);
len = list_length (arglist) + 1;
convs = make_tree_vec (len);
parmnode = parmlist;
argnode = arglist;
viable = 1;
flags = LOOKUP_NORMAL;
/* Don't bother looking up the same type twice. */
if (*candidates && (*candidates)->fn == totype)
return NULL;
for (i = 0; i < len; ++i)
{
tree arg = i == 0 ? obj : TREE_VALUE (argnode);
tree argtype = lvalue_type (arg);
tree t;
if (i == 0)
t = implicit_conversion (totype, argtype, arg, flags);
else if (parmnode == void_list_node)
break;
else if (parmnode)
t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, flags);
else
{
t = build1 (IDENTITY_CONV, argtype, arg);
ICS_ELLIPSIS_FLAG (t) = 1;
}
TREE_VEC_ELT (convs, i) = t;
if (! t)
break;
if (ICS_BAD_FLAG (t))
viable = -1;
if (i == 0)
continue;
if (parmnode)
parmnode = TREE_CHAIN (parmnode);
argnode = TREE_CHAIN (argnode);
}
if (i < len)
viable = 0;
if (!sufficient_parms_p (parmnode))
viable = 0;
return add_candidate (candidates, totype, arglist, convs, access_path,
conversion_path, viable);
}
static void
build_builtin_candidate (struct z_candidate **candidates, tree fnname,
tree type1, tree type2, tree *args, tree *argtypes,
int flags)
{
tree t, convs;
int viable = 1, i;
tree types[2];
types[0] = type1;
types[1] = type2;
convs = make_tree_vec (args[2] ? 3 : (args[1] ? 2 : 1));
for (i = 0; i < 2; ++i)
{
if (! args[i])
break;
t = implicit_conversion (types[i], argtypes[i], args[i], flags);
if (! t)
{
viable = 0;
/* We need something for printing the candidate. */
t = build1 (IDENTITY_CONV, types[i], NULL_TREE);
}
else if (ICS_BAD_FLAG (t))
viable = 0;
TREE_VEC_ELT (convs, i) = t;
}
/* For COND_EXPR we rearranged the arguments; undo that now. */
if (args[2])
{
TREE_VEC_ELT (convs, 2) = TREE_VEC_ELT (convs, 1);
TREE_VEC_ELT (convs, 1) = TREE_VEC_ELT (convs, 0);
t = implicit_conversion (boolean_type_node, argtypes[2], args[2], flags);
if (t)
TREE_VEC_ELT (convs, 0) = t;
else
viable = 0;
}
add_candidate (candidates, fnname, /*args=*/NULL_TREE, convs,
/*access_path=*/NULL_TREE,
/*conversion_path=*/NULL_TREE,
viable);
}
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 ((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, tree *args, tree *argtypes, int flags)
{
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;
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 complete 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 (TREE_CODE (type1) == POINTER_TYPE
&& (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 CONVERT_EXPR: /* unary + */
if (TREE_CODE (type1) == POINTER_TYPE)
break;
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_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 (TREE_CODE (type1) == POINTER_TYPE
&& TYPE_PTR_TO_MEMBER_P (type2))
{
tree c1 = TREE_TYPE (type1);
tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
&& (TYPE_PTRMEMFUNC_P (type2)
|| is_complete (TREE_TYPE (TREE_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.
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);
17For every pointer to member type T, there exist candidate operator
functions of the form
bool operator==(T, T);
bool operator!=(T, T); */
case MINUS_EXPR:
if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
break;
if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
{
type2 = ptrdiff_type_node;
break;
}
case MULT_EXPR:
case TRUNC_DIV_EXPR:
if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
break;
return;
case EQ_EXPR:
case NE_EXPR:
if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
|| (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
break;
if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
{
type2 = type1;
break;
}
if (TYPE_PTR_TO_MEMBER_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;
case ARRAY_REF:
if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
{
type1 = ptrdiff_type_node;
break;
}
if (TYPE_PTROB_P (type1) && INTEGRAL_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_TYPE_P (type1) && INTEGRAL_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_TYPE_P (type2))
{
type2 = ptrdiff_type_node;
break;
}
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_TYPE_P (type1) && INTEGRAL_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_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
|| ((TYPE_PTRMEMFUNC_P (type1)
|| TREE_CODE (type1) == POINTER_TYPE)
&& null_ptr_cst_p (args[1])))
{
type2 = type1;
break;
}
return;
default:
abort ();
}
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_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
|| !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_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;
default:
abort ();
}
/* 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)
&& (TREE_CODE (type1) == REFERENCE_TYPE
|| (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
|| (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
|| TYPE_PTRMEMFUNC_P (type1)
|| IS_AGGR_TYPE (type1)
|| TREE_CODE (type1) == ENUMERAL_TYPE))
{
build_builtin_candidate
(candidates, fnname, type1, type1, args, argtypes, flags);
build_builtin_candidate
(candidates, fnname, type2, type2, args, argtypes, flags);
return;
}
build_builtin_candidate
(candidates, fnname, type1, type2, args, argtypes, flags);
}
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, tree *args,
int flags)
{
int ref1, i;
int enum_p = 0;
tree type, argtypes[3];
/* TYPES[i] is the set of possible builtin-operator parameter types
we will consider for the Ith argument. These are represented as
a TREE_LIST; the TREE_VALUE of each node is the potential
parameter type. */
tree types[2];
for (i = 0; i < 3; ++i)
{
if (args[i])
argtypes[i] = lvalue_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);
return;
case TRUTH_ORIF_EXPR:
case TRUTH_ANDIF_EXPR:
build_builtin_candidate
(candidates, fnname, boolean_type_node,
boolean_type_node, args, argtypes, flags);
return;
case ADDR_EXPR:
case COMPOUND_EXPR:
case COMPONENT_REF:
return;
case COND_EXPR:
case EQ_EXPR:
case NE_EXPR:
case LT_EXPR:
case LE_EXPR:
case GT_EXPR:
case GE_EXPR:
enum_p = 1;
/* Fall through. */
default:
ref1 = 0;
}
types[0] = types[1] = NULL_TREE;
for (i = 0; i < 2; ++i)
{
if (! args[i])
;
else if (IS_AGGR_TYPE (argtypes[i]))
{
tree convs;
if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
return;
convs = lookup_conversions (argtypes[i]);
if (code == COND_EXPR)
{
if (real_lvalue_p (args[i]))
types[i] = tree_cons
(NULL_TREE, build_reference_type (argtypes[i]), types[i]);
types[i] = tree_cons
(NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
}
else if (! convs)
return;
for (; convs; convs = TREE_CHAIN (convs))
{
type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
if (i == 0 && ref1
&& (TREE_CODE (type) != REFERENCE_TYPE
|| CP_TYPE_CONST_P (TREE_TYPE (type))))
continue;
if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
types[i] = tree_cons (NULL_TREE, type, types[i]);
type = non_reference (type);
if (i != 0 || ! ref1)
{
type = TYPE_MAIN_VARIANT (type_decays_to (type));
if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
types[i] = tree_cons (NULL_TREE, type, types[i]);
if (INTEGRAL_TYPE_P (type))
type = type_promotes_to (type);
}
if (! value_member (type, types[i]))
types[i] = tree_cons (NULL_TREE, type, types[i]);
}
}
else
{
if (code == COND_EXPR && real_lvalue_p (args[i]))
types[i] = tree_cons
(NULL_TREE, build_reference_type (argtypes[i]), types[i]);
type = non_reference (argtypes[i]);
if (i != 0 || ! ref1)
{
type = TYPE_MAIN_VARIANT (type_decays_to (type));
if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
types[i] = tree_cons (NULL_TREE, type, types[i]);
if (INTEGRAL_TYPE_P (type))
type = type_promotes_to (type);
}
types[i] = tree_cons (NULL_TREE, type, types[i]);
}
}
/* Run through the possible parameter types of both arguments,
creating candidates with those parameter types. */
for (; types[0]; types[0] = TREE_CHAIN (types[0]))
{
if (types[1])
for (type = types[1]; type; type = TREE_CHAIN (type))
add_builtin_candidate
(candidates, code, code2, fnname, TREE_VALUE (types[0]),
TREE_VALUE (type), args, argtypes, flags);
else
add_builtin_candidate
(candidates, code, code2, fnname, TREE_VALUE (types[0]),
NULL_TREE, args, argtypes, flags);
}
return;
}
/* 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.
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 arglist,
tree return_type, tree access_path,
tree conversion_path, int flags, tree obj,
unification_kind_t strict)
{
int ntparms = DECL_NTPARMS (tmpl);
tree targs = make_tree_vec (ntparms);
tree args_without_in_chrg = arglist;
struct z_candidate *cand;
int i;
tree fn;
/* We don't do deduction on the in-charge parameter, the VTT
parameter or 'this'. */
if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
|| DECL_BASE_CONSTRUCTOR_P (tmpl))
&& TYPE_USES_VIRTUAL_BASECLASSES (DECL_CONTEXT (tmpl)))
args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
i = fn_type_unification (tmpl, explicit_targs, targs,
args_without_in_chrg,
return_type, strict, -1);
if (i != 0)
return NULL;
fn = instantiate_template (tmpl, targs, tf_none);
if (fn == error_mark_node)
return NULL;
/* In [class.copy]:
A member function template is never instantiated to perform the
copy of a class object to an object of its class type.
It's a little unclear what this means; the standard explicitly
does allow a template to be used to copy a class. For example,
in:
struct A {
A(A&);
template <class T> A(const T&);
};
const A f ();
void g () { A a (f ()); }
the member template will be used to make the copy. The section
quoted above appears in the paragraph that forbids constructors
whose only parameter is (a possibly cv-qualified variant of) the
class type, and a logical interpretation is that the intent was
to forbid the instantiation of member templates which would then
have that form. */
if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
{
tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
ctype))
return NULL;
}
if (obj != NULL_TREE)
/* Aha, this is a conversion function. */
cand = add_conv_candidate (candidates, fn, obj, access_path,
conversion_path, arglist);
else
cand = add_function_candidate (candidates, fn, ctype,
arglist, access_path,
conversion_path, flags);
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 = tree_cons (tmpl, targs, NULL_TREE);
else
cand->template = DECL_TEMPLATE_INFO (fn);
return cand;
}
static struct z_candidate *
add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
tree explicit_targs, tree arglist, tree return_type,
tree access_path, tree conversion_path, int flags,
unification_kind_t strict)
{
return
add_template_candidate_real (candidates, tmpl, ctype,
explicit_targs, arglist, return_type,
access_path, conversion_path,
flags, NULL_TREE, strict);
}
static struct z_candidate *
add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
tree obj, tree arglist, tree return_type,
tree access_path, tree conversion_path)
{
return
add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
arglist, return_type, access_path,
conversion_path, 0, obj, DEDUCE_CONV);
}
/* The CANDS are the set of candidates that were considered for
overload resolution. Return the set of viable candidates. If none
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;
viable = NULL;
last_viable = &viable;
*any_viable_p = false;
cand = &cands;
while (*cand)
{
struct z_candidate *c = *cand;
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;
}
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;
}
static tree
build_this (tree obj)
{
/* Fix this to work on non-lvalues. */
return build_unary_op (ADDR_EXPR, obj, 0);
}
/* 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 (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 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 (const char *msgstr, struct z_candidate *candidate)
{
if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
{
if (TREE_VEC_LENGTH (candidate->convs) == 3)
inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)),
TREE_TYPE (TREE_VEC_ELT (candidate->convs, 2)));
else if (TREE_VEC_LENGTH (candidate->convs) == 2)
inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)));
else
inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)));
}
else if (TYPE_P (candidate->fn))
inform ("%s %T <conversion>", msgstr, candidate->fn);
else if (candidate->viable == -1)
inform ("%J%s %+#D <near match>", candidate->fn, msgstr, candidate->fn);
else
inform ("%J%s %+#D", candidate->fn, msgstr, candidate->fn);
}
static void
print_z_candidates (struct z_candidate *candidates)
{
const char *str;
struct z_candidate *cand1;
struct z_candidate **cand2;
/* 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 (TREE_CODE (fn) != FUNCTION_DECL)
continue;
cand2 = &cand1->next;
while (*cand2)
{
if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
&& equal_functions (fn, (*cand2)->fn))
*cand2 = (*cand2)->next;
else
cand2 = &(*cand2)->next;
}
}
if (!candidates)
return;
str = _("candidates are:");
print_z_candidate (str, candidates);
if (candidates->next)
{
/* Indent successive candidates by the width of the translation
of the above string. */
size_t len = gcc_gettext_width (str) + 1;
char *spaces = alloca (len);
memset (spaces, ' ', len-1);
spaces[len - 1] = '\0';
candidates = candidates->next;
do
{
print_z_candidate (spaces, candidates);
candidates = candidates->next;
}
while (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 the two sequences into a single sequence,
and return the merged sequence. */
static tree
merge_conversion_sequences (tree user_seq, tree std_seq)
{
tree *t;
my_friendly_assert (TREE_CODE (user_seq) == USER_CONV,
20030306);
/* Find the end of the second conversion sequence. */
t = &(std_seq);
while (TREE_CODE (*t) != IDENTITY_CONV)
t = &TREE_OPERAND (*t, 0);
/* Replace the identity conversion with the user conversion
sequence. */
*t = user_seq;
/* The entire sequence is a user-conversion sequence. */
ICS_USER_FLAG (std_seq) = 1;
return std_seq;
}
/* 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 an lvalue 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)
{
struct z_candidate *candidates, *cand;
tree fromtype = TREE_TYPE (expr);
tree ctors = NULL_TREE, convs = NULL_TREE;
tree args = NULL_TREE;
bool any_viable_p;
/* 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]. */
my_friendly_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
|| !DERIVED_FROM_P (totype, fromtype), 20011226);
if (IS_AGGR_TYPE (totype))
ctors = lookup_fnfields (TYPE_BINFO (totype),
complete_ctor_identifier,
0);
if (IS_AGGR_TYPE (fromtype))
convs = lookup_conversions (fromtype);
candidates = 0;
flags |= LOOKUP_NO_CONVERSION;
if (ctors)
{
tree t;
ctors = BASELINK_FUNCTIONS (ctors);
t = build_int_2 (0, 0);
TREE_TYPE (t) = build_pointer_type (totype);
args = build_tree_list (NULL_TREE, expr);
/* We should never try to call the abstract or base constructor
from here. */
my_friendly_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
&& !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)),
20011226);
args = tree_cons (NULL_TREE, t, args);
}
for (; ctors; ctors = OVL_NEXT (ctors))
{
tree ctor = OVL_CURRENT (ctors);
if (DECL_NONCONVERTING_P (ctor))
continue;
if (TREE_CODE (ctor) == TEMPLATE_DECL)
cand = add_template_candidate (&candidates, ctor, totype,
NULL_TREE, args, NULL_TREE,
TYPE_BINFO (totype),
TYPE_BINFO (totype),
flags,
DEDUCE_CALL);
else
cand = add_function_candidate (&candidates, ctor, totype,
args, TYPE_BINFO (totype),
TYPE_BINFO (totype),
flags);
if (cand)
cand->second_conv = build1 (IDENTITY_CONV, totype, NULL_TREE);
}
if (convs)
args = build_tree_list (NULL_TREE, build_this (expr));
for (; convs; convs = TREE_CHAIN (convs))
{
tree fns;
tree conversion_path = TREE_PURPOSE (convs);
int convflags = LOOKUP_NO_CONVERSION;
/* If we are called to convert to a reference type, we are trying to
find an lvalue binding, so don't even consider temporaries. If
we don't find an lvalue binding, the caller will try again to
look for a temporary binding. */
if (TREE_CODE (totype) == REFERENCE_TYPE)
convflags |= LOOKUP_NO_TEMP_BIND;
for (fns = TREE_VALUE (convs); fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
/* [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.
So we pass fromtype as CTYPE to add_*_candidate. */
if (TREE_CODE (fn) == TEMPLATE_DECL)
cand = add_template_candidate (&candidates, fn, fromtype,
NULL_TREE,
args, totype,
TYPE_BINFO (fromtype),
conversion_path,
flags,
DEDUCE_CONV);
else
cand = add_function_candidate (&candidates, fn, fromtype,
args,
TYPE_BINFO (fromtype),
conversion_path,
flags);
if (cand)
{
tree ics = implicit_conversion (totype,
TREE_TYPE (TREE_TYPE (cand->fn)),
0, convflags);
cand->second_conv = ics;
if (ics == NULL_TREE)
cand->viable = 0;
else if (candidates->viable == 1 && ICS_BAD_FLAG (ics))
cand->viable = -1;
}
}
}
candidates = splice_viable (candidates, pedantic, &any_viable_p);
if (!any_viable_p)
return 0;
cand = tourney (candidates);
if (cand == 0)
{
if (flags & LOOKUP_COMPLAIN)
{
error ("conversion from `%T' to `%T' is ambiguous",
fromtype, totype);
print_z_candidates (candidates);
}
cand = candidates; /* any one will do */
cand->second_conv = build1 (AMBIG_CONV, totype, expr);
ICS_USER_FLAG (cand->second_conv) = 1;
if (!any_strictly_viable (candidates))
ICS_BAD_FLAG (cand->second_conv) = 1;
/* If there are viable candidates, don't set ICS_BAD_FLAG; an
ambiguous conversion is no worse than another user-defined
conversion. */
return cand;
}
/* Build the user conversion sequence. */
convs = build_conv
(USER_CONV,
(DECL_CONSTRUCTOR_P (cand->fn)
? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
TREE_OPERAND (convs, 1) = build_zc_wrapper (cand);
/* Combine it with the second conversion sequence. */
cand->second_conv = merge_conversion_sequences (convs,
cand->second_conv);
if (cand->viable == -1)
ICS_BAD_FLAG (cand->second_conv) = 1;
return cand;
}
tree
build_user_type_conversion (tree totype, tree expr, int flags)
{
struct z_candidate *cand
= build_user_type_conversion_1 (totype, expr, flags);
if (cand)
{
if (TREE_CODE (cand->second_conv) == AMBIG_CONV)
return error_mark_node;
return convert_from_reference (convert_like (cand->second_conv, expr));
}
return NULL_TREE;
}
/* Do any initial processing on the arguments to a function call. */
static tree
resolve_args (tree args)
{
tree t;
for (t = args; t; t = TREE_CHAIN (t))
{
tree arg = TREE_VALUE (t);
if (arg == error_mark_node)
return error_mark_node;
else if (VOID_TYPE_P (TREE_TYPE (arg)))
{
error ("invalid use of void expression");
return error_mark_node;
}
arg = convert_from_reference (arg);
TREE_VALUE (t) = arg;
}
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,
tree args,
struct z_candidate **candidates,
bool *any_viable_p)
{
struct z_candidate *cand;
tree explicit_targs = NULL_TREE;
int template_only = 0;
*candidates = NULL;
*any_viable_p = true;
/* Check FN and ARGS. */
my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
|| TREE_CODE (fn) == TEMPLATE_DECL
|| TREE_CODE (fn) == OVERLOAD
|| TREE_CODE (fn) == TEMPLATE_ID_EXPR,
20020712);
my_friendly_assert (!args || TREE_CODE (args) == TREE_LIST,
20020712);
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, args, explicit_targs, template_only,
/*conversion_path=*/NULL_TREE,
/*access_path=*/NULL_TREE,
LOOKUP_NORMAL,
candidates);
*candidates = splice_viable (*candidates, pedantic, any_viable_p);
if (!*any_viable_p)
return NULL;
cand = tourney (*candidates);
return cand;
}
/* Return an expression for a call to FN (a namespace-scope function,
or a static member function) with the ARGS. */
tree
build_new_function_call (tree fn, tree args)
{
struct z_candidate *candidates, *cand;
bool any_viable_p;
args = resolve_args (args);
if (args == error_mark_node)
return error_mark_node;
cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
if (!cand)
{
if (!any_viable_p && candidates && ! candidates->next)
return build_function_call (candidates->fn, args);
if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
fn = TREE_OPERAND (fn, 0);
if (!any_viable_p)
error ("no matching function for call to `%D(%A)'",
DECL_NAME (OVL_CURRENT (fn)), args);
else
error ("call of overloaded `%D(%A)' is ambiguous",
DECL_NAME (OVL_CURRENT (fn)), args);
if (candidates)
print_z_candidates (candidates);
return error_mark_node;
}
return build_over_call (cand, LOOKUP_NORMAL);
}
/* 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. *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. */
tree
build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
{
tree fns;
struct z_candidate *candidates;
struct z_candidate *cand;
bool any_viable_p;
args = tree_cons (NULL_TREE, *size, args);
args = resolve_args (args);
if (args == error_mark_node)
return args;
fns = lookup_function_nonclass (fnname, args);
/* Figure out what function is being called. */
cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
/* If no suitable function could be found, issue an error message
and give up. */
if (!cand)
{
if (!any_viable_p)
error ("no matching function for call to `%D(%A)'",
DECL_NAME (OVL_CURRENT (fns)), args);
else
error ("call of overloaded `%D(%A)' is ambiguous",
DECL_NAME (OVL_CURRENT (fns)), args);
if (candidates)
print_z_candidates (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;
if (!abi_version_at_least (2))
{
tree placement = TREE_CHAIN (args);
/* In G++ 3.2, the check was implemented incorrectly; it
looked at the placement expression, rather than the
type of the function. */
if (placement && !TREE_CHAIN (placement)
&& same_type_p (TREE_TYPE (TREE_VALUE (placement)),
ptr_type_node))
use_cookie = false;
}
else
{
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, *size, *cookie_size);
/* Update the argument list to reflect the adjusted size. */
TREE_VALUE (args) = *size;
}
else
*cookie_size = NULL_TREE;
}
/* Build the CALL_EXPR. */
return build_over_call (cand, LOOKUP_NORMAL);
}
static tree
build_object_call (tree obj, tree args)
{
struct z_candidate *candidates = 0, *cand;
tree fns, convs, mem_args = NULL_TREE;
tree type = TREE_TYPE (obj);
bool any_viable_p;
if (TYPE_PTRMEMFUNC_P (type))
{
/* It's no good looking for an overloaded operator() on a
pointer-to-member-function. */
error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
return error_mark_node;
}
fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
if (fns == error_mark_node)
return error_mark_node;
args = resolve_args (args);
if (args == error_mark_node)
return error_mark_node;
if (fns)
{
tree base = BINFO_TYPE (BASELINK_BINFO (fns));
mem_args = tree_cons (NULL_TREE, build_this (obj), args);
for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
if (TREE_CODE (fn) == TEMPLATE_DECL)
add_template_candidate (&candidates, fn, base, NULL_TREE,
mem_args, NULL_TREE,
TYPE_BINFO (type),
TYPE_BINFO (type),
LOOKUP_NORMAL, DEDUCE_CALL);
else
add_function_candidate
(&candidates, fn, base, mem_args, TYPE_BINFO (type),
TYPE_BINFO (type), LOOKUP_NORMAL);
}
}
convs = lookup_conversions (type);
for (; convs; convs = TREE_CHAIN (convs))
{
tree fns = TREE_VALUE (convs);
tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
if ((TREE_CODE (totype) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
|| (TREE_CODE (totype) == REFERENCE_TYPE
&& TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
|| (TREE_CODE (totype) == REFERENCE_TYPE
&& TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
for (; fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
if (TREE_CODE (fn) == TEMPLATE_DECL)
add_template_conv_candidate
(&candidates, fn, obj, args, totype,
/*access_path=*/NULL_TREE,
/*conversion_path=*/NULL_TREE);
else
add_conv_candidate (&candidates, fn, obj, args,
/*conversion_path=*/NULL_TREE,
/*access_path=*/NULL_TREE);
}
}
candidates = splice_viable (candidates, pedantic, &any_viable_p);
if (!any_viable_p)
{
error ("no match for call to `(%T) (%A)'", TREE_TYPE (obj), args);
print_z_candidates (candidates);
return error_mark_node;
}
cand = tourney (candidates);
if (cand == 0)
{
error ("call of `(%T) (%A)' is ambiguous", TREE_TYPE (obj), args);
print_z_candidates (candidates);
return error_mark_node;
}
/* Since cand->fn will be a type, not a function, for a conversion
function, we must be careful not to unconditionally look at
DECL_NAME here. */
if (TREE_CODE (cand->fn) == FUNCTION_DECL
&& DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
return build_over_call (cand, LOOKUP_NORMAL);
obj = convert_like_with_context
(TREE_VEC_ELT (cand->convs, 0), obj, cand->fn, -1);
/* FIXME */
return build_function_call (obj, args);
}
static void
op_error (enum tree_code code, enum tree_code code2,
tree arg1, tree arg2, tree arg3, const char *problem)
{
const char *opname;
if (code == MODIFY_EXPR)
opname = assignment_operator_name_info[code2].name;
else
opname = operator_name_info[code].name;
switch (code)
{
case COND_EXPR:
error ("%s for ternary 'operator?:' in '%E ? %E : %E'",
problem, arg1, arg2, arg3);
break;
case POSTINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
error ("%s for 'operator%s' in '%E%s'", problem, opname, arg1, opname);
break;
case ARRAY_REF:
error ("%s for 'operator[]' in '%E[%E]'", problem, arg1, arg2);
break;
case REALPART_EXPR:
case IMAGPART_EXPR:
error ("%s for '%s' in '%s %E'", problem, opname, opname, arg1);
break;
default:
if (arg2)
error ("%s for 'operator%s' in '%E %s %E'",
problem, opname, arg1, opname, arg2);
else
error ("%s for 'operator%s' in '%s%E'",
problem, opname, opname, arg1);
break;
}
}
/* Return the implicit conversion sequence that could be used to
convert E1 to E2 in [expr.cond]. */
static tree
conditional_conversion (tree e1, tree e2)
{
tree t1 = non_reference (TREE_TYPE (e1));
tree t2 = non_reference (TREE_TYPE (e2));
tree 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 "reference to
T2", subject to the constraint that in the conversion the
reference must bind directly (_dcl.init.ref_) to E1. */
if (real_lvalue_p (e2))
{
conv = implicit_conversion (build_reference_type (t2),
t1,
e1,
LOOKUP_NO_TEMP_BIND);
if (conv)
return conv;
}
/* [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 = build1 (IDENTITY_CONV, t1, e1);
if (!same_type_p (TYPE_MAIN_VARIANT (t1),
TYPE_MAIN_VARIANT (t2)))
conv = build_conv (BASE_CONV, t2, conv);
else
conv = build_conv (RVALUE_CONV, t2, conv);
return conv;
}
else
return NULL_TREE;
}
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, LOOKUP_NORMAL);
}
/* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
arguments to the conditional expression. */
tree
build_conditional_expr (tree arg1, tree arg2, tree arg3)
{
tree arg2_type;
tree arg3_type;
tree result;
tree result_type = NULL_TREE;
bool lvalue_p = true;
struct z_candidate *candidates = 0;
struct z_candidate *cand;
/* 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 (pedantic)
pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
/* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
if (real_lvalue_p (arg1))
arg2 = arg1 = stabilize_reference (arg1);
else
arg2 = arg1 = save_expr (arg1);
}
/* [expr.cond]
The first expr ession is implicitly converted to bool (clause
_conv_). */
arg1 = perform_implicit_conversion (boolean_type_node, 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;
/* [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 = TREE_TYPE (arg2);
arg3_type = TREE_TYPE (arg3);
if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
{
/* Do the conversions. We don't these for `void' type arguments
since it can't have any effect and since decay_conversion
does not handle that case gracefully. */
if (!VOID_TYPE_P (arg2_type))
arg2 = decay_conversion (arg2);
if (!VOID_TYPE_P (arg3_type))
arg3 = decay_conversion (arg3);
arg2_type = TREE_TYPE (arg2);
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 of the other and is an rvalue.
--Both the second and the third operands have type void; the
result is of type void and is an rvalue.
We must avoid calling force_rvalue for expressions of type
"void" because it will complain that their value is being
used. */
if (TREE_CODE (arg2) == THROW_EXPR
&& TREE_CODE (arg3) != THROW_EXPR)
{
if (!VOID_TYPE_P (arg3_type))
arg3 = force_rvalue (arg3);
arg3_type = TREE_TYPE (arg3);
result_type = arg3_type;
}
else if (TREE_CODE (arg2) != THROW_EXPR
&& TREE_CODE (arg3) == THROW_EXPR)
{
if (!VOID_TYPE_P (arg2_type))
arg2 = force_rvalue (arg2);
arg2_type = TREE_TYPE (arg2);
result_type = arg2_type;
}
else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
result_type = void_type_node;
else
{
error ("`%E' has type `void' and is not a throw-expression",
VOID_TYPE_P (arg2_type) ? arg2 : arg3);
return error_mark_node;
}
lvalue_p = false;
goto valid_operands;
}
/* [expr.cond]
Otherwise, if the second and third operand have different types,
and either has (possibly cv-qualified) class type, 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)))
{
tree conv2 = conditional_conversion (arg2, arg3);
tree conv3 = conditional_conversion (arg3, arg2);
/* [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 && !ICS_BAD_FLAG (conv2)
&& conv3 && !ICS_BAD_FLAG (conv3))
|| (conv2 && TREE_CODE (conv2) == AMBIG_CONV)
|| (conv3 && TREE_CODE (conv3) == AMBIG_CONV))
{
error ("operands to ?: have different types");
return error_mark_node;
}
else if (conv2 && !ICS_BAD_FLAG (conv2))
{
arg2 = convert_like (conv2, arg2);
arg2 = convert_from_reference (arg2);
arg2_type = TREE_TYPE (arg2);
}
else if (conv3 && !ICS_BAD_FLAG (conv3))
{
arg3 = convert_like (conv3, arg3);
arg3 = convert_from_reference (arg3);
arg3_type = TREE_TYPE (arg3);
}
/* 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 actuall 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 ((conv2 || conv3)
&& CLASS_TYPE_P (arg2_type)
&& TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
arg2_type = arg3_type =
cp_build_qualified_type (arg2_type,
TYPE_QUALS (arg2_type)
| TYPE_QUALS (arg3_type));
}
/* [expr.cond]
If the second and third operands are lvalues and have the same
type, the result is of that type and is an lvalue. */
if (real_lvalue_p (arg2)
&& real_lvalue_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_). */
lvalue_p = false;
if (!same_type_p (arg2_type, arg3_type)
&& (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
{
tree args[3];
tree conv;
bool any_viable_p;
/* Rearrange the arguments so that add_builtin_candidate only has
to know about two args. In build_builtin_candidates, the
arguments are unscrambled. */
args[0] = arg2;
args[1] = arg3;
args[2] = arg1;
add_builtin_candidates (&candidates,
COND_EXPR,
NOP_EXPR,
ansi_opname (COND_EXPR),
args,
LOOKUP_NORMAL);
/* [expr.cond]
If the overload resolution fails, the program is
ill-formed. */
candidates = splice_viable (candidates, pedantic, &any_viable_p);
if (!any_viable_p)
{
op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
print_z_candidates (candidates);
return error_mark_node;
}
cand = tourney (candidates);
if (!cand)
{
op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
print_z_candidates (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 = TREE_VEC_ELT (cand->convs, 0);
arg1 = convert_like (conv, arg1);
conv = TREE_VEC_ELT (cand->convs, 1);
arg2 = convert_like (conv, arg2);
conv = TREE_VEC_ELT (cand->convs, 2);
arg3 = convert_like (conv, 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);
if (!CLASS_TYPE_P (arg2_type))
arg2_type = TREE_TYPE (arg2);
arg3 = force_rvalue (arg3);
if (!CLASS_TYPE_P (arg2_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)
|| TREE_CODE (arg2_type) == ENUMERAL_TYPE)
&& (ARITHMETIC_TYPE_P (arg3_type)
|| TREE_CODE (arg3_type) == ENUMERAL_TYPE))