| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S E M _ C H 6 -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2003, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 2, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT 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 distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- |
| -- MA 02111-1307, USA. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with Atree; use Atree; |
| with Checks; use Checks; |
| with Debug; use Debug; |
| with Einfo; use Einfo; |
| with Elists; use Elists; |
| with Errout; use Errout; |
| with Expander; use Expander; |
| with Exp_Ch7; use Exp_Ch7; |
| with Fname; use Fname; |
| with Freeze; use Freeze; |
| with Lib.Xref; use Lib.Xref; |
| with Namet; use Namet; |
| with Lib; use Lib; |
| with Nlists; use Nlists; |
| with Nmake; use Nmake; |
| with Opt; use Opt; |
| with Output; use Output; |
| with Rtsfind; use Rtsfind; |
| with Sem; use Sem; |
| with Sem_Cat; use Sem_Cat; |
| with Sem_Ch3; use Sem_Ch3; |
| with Sem_Ch4; use Sem_Ch4; |
| with Sem_Ch5; use Sem_Ch5; |
| with Sem_Ch8; use Sem_Ch8; |
| with Sem_Ch12; use Sem_Ch12; |
| with Sem_Disp; use Sem_Disp; |
| with Sem_Dist; use Sem_Dist; |
| with Sem_Elim; use Sem_Elim; |
| with Sem_Eval; use Sem_Eval; |
| with Sem_Mech; use Sem_Mech; |
| with Sem_Prag; use Sem_Prag; |
| with Sem_Res; use Sem_Res; |
| with Sem_Util; use Sem_Util; |
| with Sem_Type; use Sem_Type; |
| with Sem_Warn; use Sem_Warn; |
| with Sinput; use Sinput; |
| with Stand; use Stand; |
| with Sinfo; use Sinfo; |
| with Sinfo.CN; use Sinfo.CN; |
| with Snames; use Snames; |
| with Stringt; use Stringt; |
| with Style; |
| with Stylesw; use Stylesw; |
| with Tbuild; use Tbuild; |
| with Uintp; use Uintp; |
| with Urealp; use Urealp; |
| with Validsw; use Validsw; |
| |
| package body Sem_Ch6 is |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| procedure Analyze_Generic_Subprogram_Body (N : Node_Id; Gen_Id : Entity_Id); |
| -- Analyze a generic subprogram body. N is the body to be analyzed, |
| -- and Gen_Id is the defining entity Id for the corresponding spec. |
| |
| procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id); |
| -- If a subprogram has pragma Inline and inlining is active, use generic |
| -- machinery to build an unexpanded body for the subprogram. This body is |
| -- subsequenty used for inline expansions at call sites. If subprogram can |
| -- be inlined (depending on size and nature of local declarations) this |
| -- function returns true. Otherwise subprogram body is treated normally. |
| |
| type Conformance_Type is |
| (Type_Conformant, Mode_Conformant, Subtype_Conformant, Fully_Conformant); |
| -- Conformance type used for following call, meaning matches the |
| -- RM definitions of the corresponding terms. |
| |
| procedure Check_Conformance |
| (New_Id : Entity_Id; |
| Old_Id : Entity_Id; |
| Ctype : Conformance_Type; |
| Errmsg : Boolean; |
| Conforms : out Boolean; |
| Err_Loc : Node_Id := Empty; |
| Get_Inst : Boolean := False); |
| -- Given two entities, this procedure checks that the profiles associated |
| -- with these entities meet the conformance criterion given by the third |
| -- parameter. If they conform, Conforms is set True and control returns |
| -- to the caller. If they do not conform, Conforms is set to False, and |
| -- in addition, if Errmsg is True on the call, proper messages are output |
| -- to complain about the conformance failure. If Err_Loc is non_Empty |
| -- the error messages are placed on Err_Loc, if Err_Loc is empty, then |
| -- error messages are placed on the appropriate part of the construct |
| -- denoted by New_Id. If Get_Inst is true, then this is a mode conformance |
| -- against a formal access-to-subprogram type so Get_Instance_Of must |
| -- be called. |
| |
| procedure Check_Overriding_Operation |
| (N : Node_Id; |
| Subp : Entity_Id); |
| -- Check that a subprogram with a pragma Overriding or Optional_Overriding |
| -- is legal. This check is performed here rather than in Sem_Prag because |
| -- the pragma must follow immediately the declaration, and can be treated |
| -- as part of the declaration itself, as described in AI-218. |
| |
| procedure Check_Subprogram_Order (N : Node_Id); |
| -- N is the N_Subprogram_Body node for a subprogram. This routine applies |
| -- the alpha ordering rule for N if this ordering requirement applicable. |
| |
| function Is_Non_Overriding_Operation |
| (Prev_E : Entity_Id; |
| New_E : Entity_Id) return Boolean; |
| -- Enforce the rule given in 12.3(18): a private operation in an instance |
| -- overrides an inherited operation only if the corresponding operation |
| -- was overriding in the generic. This can happen for primitive operations |
| -- of types derived (in the generic unit) from formal private or formal |
| -- derived types. |
| |
| procedure Check_Returns |
| (HSS : Node_Id; |
| Mode : Character; |
| Err : out Boolean); |
| -- Called to check for missing return statements in a function body, |
| -- or for returns present in a procedure body which has No_Return set. |
| -- L is the handled statement sequence for the subprogram body. This |
| -- procedure checks all flow paths to make sure they either have a |
| -- return (Mode = 'F') or do not have a return (Mode = 'P'). The flag |
| -- Err is set if there are any control paths not explicitly terminated |
| -- by a return in the function case, and is True otherwise. |
| |
| function Conforming_Types |
| (T1 : Entity_Id; |
| T2 : Entity_Id; |
| Ctype : Conformance_Type; |
| Get_Inst : Boolean := False) return Boolean; |
| -- Check that two formal parameter types conform, checking both |
| -- for equality of base types, and where required statically |
| -- matching subtypes, depending on the setting of Ctype. |
| |
| procedure Enter_Overloaded_Entity (S : Entity_Id); |
| -- This procedure makes S, a new overloaded entity, into the first |
| -- visible entity with that name. |
| |
| procedure Install_Entity (E : Entity_Id); |
| -- Make single entity visible. Used for generic formals as well. |
| |
| procedure Install_Formals (Id : Entity_Id); |
| -- On entry to a subprogram body, make the formals visible. Note |
| -- that simply placing the subprogram on the scope stack is not |
| -- sufficient: the formals must become the current entities for |
| -- their names. |
| |
| procedure Make_Inequality_Operator (S : Entity_Id); |
| -- Create the declaration for an inequality operator that is implicitly |
| -- created by a user-defined equality operator that yields a boolean. |
| |
| procedure May_Need_Actuals (Fun : Entity_Id); |
| -- Flag functions that can be called without parameters, i.e. those that |
| -- have no parameters, or those for which defaults exist for all parameters |
| |
| procedure Reference_Body_Formals (Spec : Entity_Id; Bod : Entity_Id); |
| -- If there is a separate spec for a subprogram or generic subprogram, |
| -- the formals of the body are treated as references to the corresponding |
| -- formals of the spec. This reference does not count as an actual use of |
| -- the formal, in order to diagnose formals that are unused in the body. |
| |
| procedure Set_Formal_Validity (Formal_Id : Entity_Id); |
| -- Formal_Id is an formal parameter entity. This procedure deals with |
| -- setting the proper validity status for this entity, which depends |
| -- on the kind of parameter and the validity checking mode. |
| |
| --------------------------------------------- |
| -- Analyze_Abstract_Subprogram_Declaration -- |
| --------------------------------------------- |
| |
| procedure Analyze_Abstract_Subprogram_Declaration (N : Node_Id) is |
| Designator : constant Entity_Id := |
| Analyze_Subprogram_Specification (Specification (N)); |
| Scop : constant Entity_Id := Current_Scope; |
| |
| begin |
| Generate_Definition (Designator); |
| Set_Is_Abstract (Designator); |
| New_Overloaded_Entity (Designator); |
| Check_Delayed_Subprogram (Designator); |
| |
| Set_Categorization_From_Scope (Designator, Scop); |
| |
| if Ekind (Scope (Designator)) = E_Protected_Type then |
| Error_Msg_N |
| ("abstract subprogram not allowed in protected type", N); |
| end if; |
| |
| Generate_Reference_To_Formals (Designator); |
| end Analyze_Abstract_Subprogram_Declaration; |
| |
| ---------------------------- |
| -- Analyze_Function_Call -- |
| ---------------------------- |
| |
| procedure Analyze_Function_Call (N : Node_Id) is |
| P : constant Node_Id := Name (N); |
| L : constant List_Id := Parameter_Associations (N); |
| Actual : Node_Id; |
| |
| begin |
| Analyze (P); |
| |
| -- If error analyzing name, then set Any_Type as result type and return |
| |
| if Etype (P) = Any_Type then |
| Set_Etype (N, Any_Type); |
| return; |
| end if; |
| |
| -- Otherwise analyze the parameters |
| |
| if Present (L) then |
| Actual := First (L); |
| |
| while Present (Actual) loop |
| Analyze (Actual); |
| Check_Parameterless_Call (Actual); |
| Next (Actual); |
| end loop; |
| end if; |
| |
| Analyze_Call (N); |
| end Analyze_Function_Call; |
| |
| ------------------------------------- |
| -- Analyze_Generic_Subprogram_Body -- |
| ------------------------------------- |
| |
| procedure Analyze_Generic_Subprogram_Body |
| (N : Node_Id; |
| Gen_Id : Entity_Id) |
| is |
| Gen_Decl : constant Node_Id := Unit_Declaration_Node (Gen_Id); |
| Kind : constant Entity_Kind := Ekind (Gen_Id); |
| Body_Id : Entity_Id; |
| New_N : Node_Id; |
| Spec : Node_Id; |
| |
| begin |
| -- Copy body and disable expansion while analyzing the generic |
| -- For a stub, do not copy the stub (which would load the proper body), |
| -- this will be done when the proper body is analyzed. |
| |
| if Nkind (N) /= N_Subprogram_Body_Stub then |
| New_N := Copy_Generic_Node (N, Empty, Instantiating => False); |
| Rewrite (N, New_N); |
| Start_Generic; |
| end if; |
| |
| Spec := Specification (N); |
| |
| -- Within the body of the generic, the subprogram is callable, and |
| -- behaves like the corresponding non-generic unit. |
| |
| Body_Id := Defining_Entity (Spec); |
| |
| if Kind = E_Generic_Procedure |
| and then Nkind (Spec) /= N_Procedure_Specification |
| then |
| Error_Msg_N ("invalid body for generic procedure ", Body_Id); |
| return; |
| |
| elsif Kind = E_Generic_Function |
| and then Nkind (Spec) /= N_Function_Specification |
| then |
| Error_Msg_N ("invalid body for generic function ", Body_Id); |
| return; |
| end if; |
| |
| Set_Corresponding_Body (Gen_Decl, Body_Id); |
| |
| if Has_Completion (Gen_Id) |
| and then Nkind (Parent (N)) /= N_Subunit |
| then |
| Error_Msg_N ("duplicate generic body", N); |
| return; |
| else |
| Set_Has_Completion (Gen_Id); |
| end if; |
| |
| if Nkind (N) = N_Subprogram_Body_Stub then |
| Set_Ekind (Defining_Entity (Specification (N)), Kind); |
| else |
| Set_Corresponding_Spec (N, Gen_Id); |
| end if; |
| |
| if Nkind (Parent (N)) = N_Compilation_Unit then |
| Set_Cunit_Entity (Current_Sem_Unit, Defining_Entity (N)); |
| end if; |
| |
| -- Make generic parameters immediately visible in the body. They are |
| -- needed to process the formals declarations. Then make the formals |
| -- visible in a separate step. |
| |
| New_Scope (Gen_Id); |
| |
| declare |
| E : Entity_Id; |
| First_Ent : Entity_Id; |
| |
| begin |
| First_Ent := First_Entity (Gen_Id); |
| |
| E := First_Ent; |
| while Present (E) and then not Is_Formal (E) loop |
| Install_Entity (E); |
| Next_Entity (E); |
| end loop; |
| |
| Set_Use (Generic_Formal_Declarations (Gen_Decl)); |
| |
| -- Now generic formals are visible, and the specification can be |
| -- analyzed, for subsequent conformance check. |
| |
| Body_Id := Analyze_Subprogram_Specification (Spec); |
| |
| -- Make formal parameters visible |
| |
| if Present (E) then |
| |
| -- E is the first formal parameter, we loop through the formals |
| -- installing them so that they will be visible. |
| |
| Set_First_Entity (Gen_Id, E); |
| while Present (E) loop |
| Install_Entity (E); |
| Next_Formal (E); |
| end loop; |
| end if; |
| |
| -- Visible generic entity is callable within its own body. |
| |
| Set_Ekind (Gen_Id, Ekind (Body_Id)); |
| Set_Ekind (Body_Id, E_Subprogram_Body); |
| Set_Convention (Body_Id, Convention (Gen_Id)); |
| Set_Scope (Body_Id, Scope (Gen_Id)); |
| Check_Fully_Conformant (Body_Id, Gen_Id, Body_Id); |
| |
| if Nkind (N) = N_Subprogram_Body_Stub then |
| |
| -- No body to analyze, so restore state of generic unit. |
| |
| Set_Ekind (Gen_Id, Kind); |
| Set_Ekind (Body_Id, Kind); |
| |
| if Present (First_Ent) then |
| Set_First_Entity (Gen_Id, First_Ent); |
| end if; |
| |
| End_Scope; |
| return; |
| end if; |
| |
| -- If this is a compilation unit, it must be made visible |
| -- explicitly, because the compilation of the declaration, |
| -- unlike other library unit declarations, does not. If it |
| -- is not a unit, the following is redundant but harmless. |
| |
| Set_Is_Immediately_Visible (Gen_Id); |
| Reference_Body_Formals (Gen_Id, Body_Id); |
| |
| Set_Actual_Subtypes (N, Current_Scope); |
| Analyze_Declarations (Declarations (N)); |
| Check_Completion; |
| Analyze (Handled_Statement_Sequence (N)); |
| |
| Save_Global_References (Original_Node (N)); |
| |
| -- Prior to exiting the scope, include generic formals again |
| -- (if any are present) in the set of local entities. |
| |
| if Present (First_Ent) then |
| Set_First_Entity (Gen_Id, First_Ent); |
| end if; |
| |
| Check_References (Gen_Id); |
| end; |
| |
| End_Scope; |
| Check_Subprogram_Order (N); |
| |
| -- Outside of its body, unit is generic again. |
| |
| Set_Ekind (Gen_Id, Kind); |
| Generate_Reference (Gen_Id, Body_Id, 'b', Set_Ref => False); |
| Style.Check_Identifier (Body_Id, Gen_Id); |
| End_Generic; |
| end Analyze_Generic_Subprogram_Body; |
| |
| ----------------------------- |
| -- Analyze_Operator_Symbol -- |
| ----------------------------- |
| |
| -- An operator symbol such as "+" or "and" may appear in context where |
| -- the literal denotes an entity name, such as "+"(x, y) or in a |
| -- context when it is just a string, as in (conjunction = "or"). In |
| -- these cases the parser generates this node, and the semantics does |
| -- the disambiguation. Other such case are actuals in an instantiation, |
| -- the generic unit in an instantiation, and pragma arguments. |
| |
| procedure Analyze_Operator_Symbol (N : Node_Id) is |
| Par : constant Node_Id := Parent (N); |
| |
| begin |
| if (Nkind (Par) = N_Function_Call and then N = Name (Par)) |
| or else Nkind (Par) = N_Function_Instantiation |
| or else (Nkind (Par) = N_Indexed_Component and then N = Prefix (Par)) |
| or else (Nkind (Par) = N_Pragma_Argument_Association |
| and then not Is_Pragma_String_Literal (Par)) |
| or else Nkind (Par) = N_Subprogram_Renaming_Declaration |
| or else (Nkind (Par) = N_Attribute_Reference |
| and then Attribute_Name (Par) /= Name_Value) |
| then |
| Find_Direct_Name (N); |
| |
| else |
| Change_Operator_Symbol_To_String_Literal (N); |
| Analyze (N); |
| end if; |
| end Analyze_Operator_Symbol; |
| |
| ----------------------------------- |
| -- Analyze_Parameter_Association -- |
| ----------------------------------- |
| |
| procedure Analyze_Parameter_Association (N : Node_Id) is |
| begin |
| Analyze (Explicit_Actual_Parameter (N)); |
| end Analyze_Parameter_Association; |
| |
| ---------------------------- |
| -- Analyze_Procedure_Call -- |
| ---------------------------- |
| |
| procedure Analyze_Procedure_Call (N : Node_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| P : constant Node_Id := Name (N); |
| Actuals : constant List_Id := Parameter_Associations (N); |
| Actual : Node_Id; |
| New_N : Node_Id; |
| |
| procedure Analyze_Call_And_Resolve; |
| -- Do Analyze and Resolve calls for procedure call |
| |
| ------------------------------ |
| -- Analyze_Call_And_Resolve -- |
| ------------------------------ |
| |
| procedure Analyze_Call_And_Resolve is |
| begin |
| if Nkind (N) = N_Procedure_Call_Statement then |
| Analyze_Call (N); |
| Resolve (N, Standard_Void_Type); |
| else |
| Analyze (N); |
| end if; |
| end Analyze_Call_And_Resolve; |
| |
| -- Start of processing for Analyze_Procedure_Call |
| |
| begin |
| -- The syntactic construct: PREFIX ACTUAL_PARAMETER_PART can denote |
| -- a procedure call or an entry call. The prefix may denote an access |
| -- to subprogram type, in which case an implicit dereference applies. |
| -- If the prefix is an indexed component (without implicit defererence) |
| -- then the construct denotes a call to a member of an entire family. |
| -- If the prefix is a simple name, it may still denote a call to a |
| -- parameterless member of an entry family. Resolution of these various |
| -- interpretations is delicate. |
| |
| Analyze (P); |
| |
| -- If error analyzing prefix, then set Any_Type as result and return |
| |
| if Etype (P) = Any_Type then |
| Set_Etype (N, Any_Type); |
| return; |
| end if; |
| |
| -- Otherwise analyze the parameters |
| |
| if Present (Actuals) then |
| Actual := First (Actuals); |
| |
| while Present (Actual) loop |
| Analyze (Actual); |
| Check_Parameterless_Call (Actual); |
| Next (Actual); |
| end loop; |
| end if; |
| |
| -- Special processing for Elab_Spec and Elab_Body calls |
| |
| if Nkind (P) = N_Attribute_Reference |
| and then (Attribute_Name (P) = Name_Elab_Spec |
| or else Attribute_Name (P) = Name_Elab_Body) |
| then |
| if Present (Actuals) then |
| Error_Msg_N |
| ("no parameters allowed for this call", First (Actuals)); |
| return; |
| end if; |
| |
| Set_Etype (N, Standard_Void_Type); |
| Set_Analyzed (N); |
| |
| elsif Is_Entity_Name (P) |
| and then Is_Record_Type (Etype (Entity (P))) |
| and then Remote_AST_I_Dereference (P) |
| then |
| return; |
| |
| elsif Is_Entity_Name (P) |
| and then Ekind (Entity (P)) /= E_Entry_Family |
| then |
| if Is_Access_Type (Etype (P)) |
| and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type |
| and then No (Actuals) |
| and then Comes_From_Source (N) |
| then |
| Error_Msg_N ("missing explicit dereference in call", N); |
| end if; |
| |
| Analyze_Call_And_Resolve; |
| |
| -- If the prefix is the simple name of an entry family, this is |
| -- a parameterless call from within the task body itself. |
| |
| elsif Is_Entity_Name (P) |
| and then Nkind (P) = N_Identifier |
| and then Ekind (Entity (P)) = E_Entry_Family |
| and then Present (Actuals) |
| and then No (Next (First (Actuals))) |
| then |
| -- Can be call to parameterless entry family. What appears to be |
| -- the sole argument is in fact the entry index. Rewrite prefix |
| -- of node accordingly. Source representation is unchanged by this |
| -- transformation. |
| |
| New_N := |
| Make_Indexed_Component (Loc, |
| Prefix => |
| Make_Selected_Component (Loc, |
| Prefix => New_Occurrence_Of (Scope (Entity (P)), Loc), |
| Selector_Name => New_Occurrence_Of (Entity (P), Loc)), |
| Expressions => Actuals); |
| Set_Name (N, New_N); |
| Set_Etype (New_N, Standard_Void_Type); |
| Set_Parameter_Associations (N, No_List); |
| Analyze_Call_And_Resolve; |
| |
| elsif Nkind (P) = N_Explicit_Dereference then |
| if Ekind (Etype (P)) = E_Subprogram_Type then |
| Analyze_Call_And_Resolve; |
| else |
| Error_Msg_N ("expect access to procedure in call", P); |
| end if; |
| |
| -- The name can be a selected component or an indexed component |
| -- that yields an access to subprogram. Such a prefix is legal if |
| -- the call has parameter associations. |
| |
| elsif Is_Access_Type (Etype (P)) |
| and then Ekind (Designated_Type (Etype (P))) = E_Subprogram_Type |
| then |
| if Present (Actuals) then |
| Analyze_Call_And_Resolve; |
| else |
| Error_Msg_N ("missing explicit dereference in call ", N); |
| end if; |
| |
| -- If not an access to subprogram, then the prefix must resolve to |
| -- the name of an entry, entry family, or protected operation. |
| |
| -- For the case of a simple entry call, P is a selected component |
| -- where the prefix is the task and the selector name is the entry. |
| -- A call to a protected procedure will have the same syntax. If |
| -- the protected object contains overloaded operations, the entity |
| -- may appear as a function, the context will select the operation |
| -- whose type is Void. |
| |
| elsif Nkind (P) = N_Selected_Component |
| and then (Ekind (Entity (Selector_Name (P))) = E_Entry |
| or else |
| Ekind (Entity (Selector_Name (P))) = E_Procedure |
| or else |
| Ekind (Entity (Selector_Name (P))) = E_Function) |
| then |
| Analyze_Call_And_Resolve; |
| |
| elsif Nkind (P) = N_Selected_Component |
| and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family |
| and then Present (Actuals) |
| and then No (Next (First (Actuals))) |
| then |
| -- Can be call to parameterless entry family. What appears to be |
| -- the sole argument is in fact the entry index. Rewrite prefix |
| -- of node accordingly. Source representation is unchanged by this |
| -- transformation. |
| |
| New_N := |
| Make_Indexed_Component (Loc, |
| Prefix => New_Copy (P), |
| Expressions => Actuals); |
| Set_Name (N, New_N); |
| Set_Etype (New_N, Standard_Void_Type); |
| Set_Parameter_Associations (N, No_List); |
| Analyze_Call_And_Resolve; |
| |
| -- For the case of a reference to an element of an entry family, P is |
| -- an indexed component whose prefix is a selected component (task and |
| -- entry family), and whose index is the entry family index. |
| |
| elsif Nkind (P) = N_Indexed_Component |
| and then Nkind (Prefix (P)) = N_Selected_Component |
| and then Ekind (Entity (Selector_Name (Prefix (P)))) = E_Entry_Family |
| then |
| Analyze_Call_And_Resolve; |
| |
| -- If the prefix is the name of an entry family, it is a call from |
| -- within the task body itself. |
| |
| elsif Nkind (P) = N_Indexed_Component |
| and then Nkind (Prefix (P)) = N_Identifier |
| and then Ekind (Entity (Prefix (P))) = E_Entry_Family |
| then |
| New_N := |
| Make_Selected_Component (Loc, |
| Prefix => New_Occurrence_Of (Scope (Entity (Prefix (P))), Loc), |
| Selector_Name => New_Occurrence_Of (Entity (Prefix (P)), Loc)); |
| Rewrite (Prefix (P), New_N); |
| Analyze (P); |
| Analyze_Call_And_Resolve; |
| |
| -- Anything else is an error. |
| |
| else |
| Error_Msg_N ("Invalid procedure or entry call", N); |
| end if; |
| end Analyze_Procedure_Call; |
| |
| ------------------------------ |
| -- Analyze_Return_Statement -- |
| ------------------------------ |
| |
| procedure Analyze_Return_Statement (N : Node_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| Expr : Node_Id; |
| Scope_Id : Entity_Id; |
| Kind : Entity_Kind; |
| R_Type : Entity_Id; |
| |
| begin |
| -- Find subprogram or accept statement enclosing the return statement |
| |
| Scope_Id := Empty; |
| for J in reverse 0 .. Scope_Stack.Last loop |
| Scope_Id := Scope_Stack.Table (J).Entity; |
| exit when Ekind (Scope_Id) /= E_Block and then |
| Ekind (Scope_Id) /= E_Loop; |
| end loop; |
| |
| pragma Assert (Present (Scope_Id)); |
| |
| Kind := Ekind (Scope_Id); |
| Expr := Expression (N); |
| |
| if Kind /= E_Function |
| and then Kind /= E_Generic_Function |
| and then Kind /= E_Procedure |
| and then Kind /= E_Generic_Procedure |
| and then Kind /= E_Entry |
| and then Kind /= E_Entry_Family |
| then |
| Error_Msg_N ("illegal context for return statement", N); |
| |
| elsif Present (Expr) then |
| if Kind = E_Function or else Kind = E_Generic_Function then |
| Set_Return_Present (Scope_Id); |
| R_Type := Etype (Scope_Id); |
| Set_Return_Type (N, R_Type); |
| Analyze_And_Resolve (Expr, R_Type); |
| |
| if (Is_Class_Wide_Type (Etype (Expr)) |
| or else Is_Dynamically_Tagged (Expr)) |
| and then not Is_Class_Wide_Type (R_Type) |
| then |
| Error_Msg_N |
| ("dynamically tagged expression not allowed!", Expr); |
| end if; |
| |
| Apply_Constraint_Check (Expr, R_Type); |
| |
| -- ??? A real run-time accessibility check is needed |
| -- in cases involving dereferences of access parameters. |
| -- For now we just check the static cases. |
| |
| if Is_Return_By_Reference_Type (Etype (Scope_Id)) |
| and then Object_Access_Level (Expr) |
| > Subprogram_Access_Level (Scope_Id) |
| then |
| Rewrite (N, |
| Make_Raise_Program_Error (Loc, |
| Reason => PE_Accessibility_Check_Failed)); |
| Analyze (N); |
| |
| Error_Msg_N |
| ("cannot return a local value by reference?", N); |
| Error_Msg_NE |
| ("& will be raised at run time?!", |
| N, Standard_Program_Error); |
| end if; |
| |
| elsif Kind = E_Procedure or else Kind = E_Generic_Procedure then |
| Error_Msg_N ("procedure cannot return value (use function)", N); |
| |
| else |
| Error_Msg_N ("accept statement cannot return value", N); |
| end if; |
| |
| -- No expression present |
| |
| else |
| if Kind = E_Function or Kind = E_Generic_Function then |
| Error_Msg_N ("missing expression in return from function", N); |
| end if; |
| |
| if (Ekind (Scope_Id) = E_Procedure |
| or else Ekind (Scope_Id) = E_Generic_Procedure) |
| and then No_Return (Scope_Id) |
| then |
| Error_Msg_N |
| ("RETURN statement not allowed (No_Return)", N); |
| end if; |
| end if; |
| |
| Check_Unreachable_Code (N); |
| end Analyze_Return_Statement; |
| |
| ----------------------------- |
| -- Analyze_Subprogram_Body -- |
| ----------------------------- |
| |
| -- This procedure is called for regular subprogram bodies, generic bodies, |
| -- and for subprogram stubs of both kinds. In the case of stubs, only the |
| -- specification matters, and is used to create a proper declaration for |
| -- the subprogram, or to perform conformance checks. |
| |
| procedure Analyze_Subprogram_Body (N : Node_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| Body_Spec : constant Node_Id := Specification (N); |
| Body_Id : Entity_Id := Defining_Entity (Body_Spec); |
| Prev_Id : constant Entity_Id := Current_Entity_In_Scope (Body_Id); |
| Body_Deleted : constant Boolean := False; |
| |
| HSS : Node_Id; |
| Spec_Id : Entity_Id; |
| Spec_Decl : Node_Id := Empty; |
| Last_Formal : Entity_Id := Empty; |
| Conformant : Boolean; |
| Missing_Ret : Boolean; |
| P_Ent : Entity_Id; |
| |
| begin |
| if Debug_Flag_C then |
| Write_Str ("==== Compiling subprogram body "); |
| Write_Name (Chars (Body_Id)); |
| Write_Str (" from "); |
| Write_Location (Loc); |
| Write_Eol; |
| end if; |
| |
| Trace_Scope (N, Body_Id, " Analyze subprogram"); |
| |
| -- Generic subprograms are handled separately. They always have |
| -- a generic specification. Determine whether current scope has |
| -- a previous declaration. |
| |
| -- If the subprogram body is defined within an instance of the |
| -- same name, the instance appears as a package renaming, and |
| -- will be hidden within the subprogram. |
| |
| if Present (Prev_Id) |
| and then not Is_Overloadable (Prev_Id) |
| and then (Nkind (Parent (Prev_Id)) /= N_Package_Renaming_Declaration |
| or else Comes_From_Source (Prev_Id)) |
| then |
| if Is_Generic_Subprogram (Prev_Id) then |
| Spec_Id := Prev_Id; |
| Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id)); |
| Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id)); |
| |
| Analyze_Generic_Subprogram_Body (N, Spec_Id); |
| return; |
| |
| else |
| -- Previous entity conflicts with subprogram name. |
| -- Attempting to enter name will post error. |
| |
| Enter_Name (Body_Id); |
| return; |
| end if; |
| |
| -- Non-generic case, find the subprogram declaration, if one was |
| -- seen, or enter new overloaded entity in the current scope. |
| -- If the current_entity is the body_id itself, the unit is being |
| -- analyzed as part of the context of one of its subunits. No need |
| -- to redo the analysis. |
| |
| elsif Prev_Id = Body_Id |
| and then Has_Completion (Body_Id) |
| then |
| return; |
| |
| else |
| Body_Id := Analyze_Subprogram_Specification (Body_Spec); |
| |
| if Nkind (N) = N_Subprogram_Body_Stub |
| or else No (Corresponding_Spec (N)) |
| then |
| Spec_Id := Find_Corresponding_Spec (N); |
| |
| -- If this is a duplicate body, no point in analyzing it |
| |
| if Error_Posted (N) then |
| return; |
| end if; |
| |
| -- A subprogram body should cause freezing of its own |
| -- declaration, but if there was no previous explicit |
| -- declaration, then the subprogram will get frozen too |
| -- late (there may be code within the body that depends |
| -- on the subprogram having been frozen, such as uses of |
| -- extra formals), so we force it to be frozen here. |
| -- Same holds if the body and the spec are compilation units. |
| |
| if No (Spec_Id) then |
| Freeze_Before (N, Body_Id); |
| |
| elsif Nkind (Parent (N)) = N_Compilation_Unit then |
| Freeze_Before (N, Spec_Id); |
| end if; |
| else |
| Spec_Id := Corresponding_Spec (N); |
| end if; |
| end if; |
| |
| -- Do not inline any subprogram that contains nested subprograms, |
| -- since the backend inlining circuit seems to generate uninitialized |
| -- references in this case. We know this happens in the case of front |
| -- end ZCX support, but it also appears it can happen in other cases |
| -- as well. The backend often rejects attempts to inline in the case |
| -- of nested procedures anyway, so little if anything is lost by this. |
| |
| -- Do not do this test if errors have been detected, because in some |
| -- error cases, this code blows up, and we don't need it anyway if |
| -- there have been errors, since we won't get to the linker anyway. |
| |
| if Serious_Errors_Detected = 0 then |
| P_Ent := Body_Id; |
| loop |
| P_Ent := Scope (P_Ent); |
| exit when No (P_Ent) or else P_Ent = Standard_Standard; |
| |
| if Is_Subprogram (P_Ent) then |
| Set_Is_Inlined (P_Ent, False); |
| |
| if Comes_From_Source (P_Ent) |
| and then Has_Pragma_Inline (P_Ent) |
| then |
| Cannot_Inline |
| ("cannot inline& (nested subprogram)?", |
| N, P_Ent); |
| end if; |
| end if; |
| end loop; |
| end if; |
| |
| -- Case of fully private operation in the body of the protected type. |
| -- We must create a declaration for the subprogram, in order to attach |
| -- the protected subprogram that will be used in internal calls. |
| |
| if No (Spec_Id) |
| and then Comes_From_Source (N) |
| and then Is_Protected_Type (Current_Scope) |
| then |
| declare |
| Decl : Node_Id; |
| Plist : List_Id; |
| Formal : Entity_Id; |
| New_Spec : Node_Id; |
| |
| begin |
| Formal := First_Formal (Body_Id); |
| |
| -- The protected operation always has at least one formal, |
| -- namely the object itself, but it is only placed in the |
| -- parameter list if expansion is enabled. |
| |
| if Present (Formal) |
| or else Expander_Active |
| then |
| Plist := New_List; |
| |
| else |
| Plist := No_List; |
| end if; |
| |
| while Present (Formal) loop |
| Append |
| (Make_Parameter_Specification (Loc, |
| Defining_Identifier => |
| Make_Defining_Identifier (Sloc (Formal), |
| Chars => Chars (Formal)), |
| In_Present => In_Present (Parent (Formal)), |
| Out_Present => Out_Present (Parent (Formal)), |
| Parameter_Type => |
| New_Reference_To (Etype (Formal), Loc), |
| Expression => |
| New_Copy_Tree (Expression (Parent (Formal)))), |
| Plist); |
| |
| Next_Formal (Formal); |
| end loop; |
| |
| if Nkind (Body_Spec) = N_Procedure_Specification then |
| New_Spec := |
| Make_Procedure_Specification (Loc, |
| Defining_Unit_Name => |
| Make_Defining_Identifier (Sloc (Body_Id), |
| Chars => Chars (Body_Id)), |
| Parameter_Specifications => Plist); |
| else |
| New_Spec := |
| Make_Function_Specification (Loc, |
| Defining_Unit_Name => |
| Make_Defining_Identifier (Sloc (Body_Id), |
| Chars => Chars (Body_Id)), |
| Parameter_Specifications => Plist, |
| Subtype_Mark => New_Occurrence_Of (Etype (Body_Id), Loc)); |
| end if; |
| |
| Decl := |
| Make_Subprogram_Declaration (Loc, |
| Specification => New_Spec); |
| Insert_Before (N, Decl); |
| Analyze (Decl); |
| Spec_Id := Defining_Unit_Name (New_Spec); |
| Set_Has_Completion (Spec_Id); |
| Set_Convention (Spec_Id, Convention_Protected); |
| end; |
| |
| elsif Present (Spec_Id) then |
| Spec_Decl := Unit_Declaration_Node (Spec_Id); |
| end if; |
| |
| -- Place subprogram on scope stack, and make formals visible. If there |
| -- is a spec, the visible entity remains that of the spec. |
| |
| if Present (Spec_Id) then |
| Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False); |
| if Style_Check then |
| Style.Check_Identifier (Body_Id, Spec_Id); |
| end if; |
| |
| Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id)); |
| Set_Is_Child_Unit (Body_Id, Is_Child_Unit (Spec_Id)); |
| |
| if Is_Abstract (Spec_Id) then |
| Error_Msg_N ("an abstract subprogram cannot have a body", N); |
| return; |
| else |
| Set_Convention (Body_Id, Convention (Spec_Id)); |
| Set_Has_Completion (Spec_Id); |
| |
| if Is_Protected_Type (Scope (Spec_Id)) then |
| Set_Privals_Chain (Spec_Id, New_Elmt_List); |
| end if; |
| |
| -- If this is a body generated for a renaming, do not check for |
| -- full conformance. The check is redundant, because the spec of |
| -- the body is a copy of the spec in the renaming declaration, |
| -- and the test can lead to spurious errors on nested defaults. |
| |
| if Present (Spec_Decl) |
| and then not Comes_From_Source (N) |
| and then |
| (Nkind (Original_Node (Spec_Decl)) = |
| N_Subprogram_Renaming_Declaration |
| or else (Present (Corresponding_Body (Spec_Decl)) |
| and then |
| Nkind (Unit_Declaration_Node |
| (Corresponding_Body (Spec_Decl))) = |
| N_Subprogram_Renaming_Declaration)) |
| then |
| Conformant := True; |
| else |
| Check_Conformance |
| (Body_Id, Spec_Id, |
| Fully_Conformant, True, Conformant, Body_Id); |
| end if; |
| |
| -- If the body is not fully conformant, we have to decide if we |
| -- should analyze it or not. If it has a really messed up profile |
| -- then we probably should not analyze it, since we will get too |
| -- many bogus messages. |
| |
| -- Our decision is to go ahead in the non-fully conformant case |
| -- only if it is at least mode conformant with the spec. Note |
| -- that the call to Check_Fully_Conformant has issued the proper |
| -- error messages to complain about the lack of conformance. |
| |
| if not Conformant |
| and then not Mode_Conformant (Body_Id, Spec_Id) |
| then |
| return; |
| end if; |
| end if; |
| |
| if Spec_Id /= Body_Id then |
| Reference_Body_Formals (Spec_Id, Body_Id); |
| end if; |
| |
| if Nkind (N) /= N_Subprogram_Body_Stub then |
| Set_Corresponding_Spec (N, Spec_Id); |
| Install_Formals (Spec_Id); |
| Last_Formal := Last_Entity (Spec_Id); |
| New_Scope (Spec_Id); |
| |
| -- Make sure that the subprogram is immediately visible. For |
| -- child units that have no separate spec this is indispensable. |
| -- Otherwise it is safe albeit redundant. |
| |
| Set_Is_Immediately_Visible (Spec_Id); |
| end if; |
| |
| Set_Corresponding_Body (Unit_Declaration_Node (Spec_Id), Body_Id); |
| Set_Ekind (Body_Id, E_Subprogram_Body); |
| Set_Scope (Body_Id, Scope (Spec_Id)); |
| |
| -- Case of subprogram body with no previous spec |
| |
| else |
| if Style_Check |
| and then Comes_From_Source (Body_Id) |
| and then not Suppress_Style_Checks (Body_Id) |
| and then not In_Instance |
| then |
| Style.Body_With_No_Spec (N); |
| end if; |
| |
| New_Overloaded_Entity (Body_Id); |
| |
| if Nkind (N) /= N_Subprogram_Body_Stub then |
| Set_Acts_As_Spec (N); |
| Generate_Definition (Body_Id); |
| Generate_Reference |
| (Body_Id, Body_Id, 'b', Set_Ref => False, Force => True); |
| Generate_Reference_To_Formals (Body_Id); |
| Install_Formals (Body_Id); |
| New_Scope (Body_Id); |
| end if; |
| end if; |
| |
| -- If this is the proper body of a stub, we must verify that the stub |
| -- conforms to the body, and to the previous spec if one was present. |
| -- we know already that the body conforms to that spec. This test is |
| -- only required for subprograms that come from source. |
| |
| if Nkind (Parent (N)) = N_Subunit |
| and then Comes_From_Source (N) |
| and then not Error_Posted (Body_Id) |
| then |
| declare |
| Old_Id : constant Entity_Id := |
| Defining_Entity |
| (Specification (Corresponding_Stub (Parent (N)))); |
| |
| Conformant : Boolean := False; |
| |
| begin |
| if No (Spec_Id) then |
| Check_Fully_Conformant (Body_Id, Old_Id); |
| |
| else |
| Check_Conformance |
| (Body_Id, Old_Id, Fully_Conformant, False, Conformant); |
| |
| if not Conformant then |
| |
| -- The stub was taken to be a new declaration. Indicate |
| -- that it lacks a body. |
| |
| Set_Has_Completion (Old_Id, False); |
| end if; |
| end if; |
| end; |
| end if; |
| |
| Set_Has_Completion (Body_Id); |
| Check_Eliminated (Body_Id); |
| |
| if Nkind (N) = N_Subprogram_Body_Stub then |
| return; |
| |
| elsif Present (Spec_Id) |
| and then Expander_Active |
| and then (Is_Always_Inlined (Spec_Id) |
| or else (Has_Pragma_Inline (Spec_Id) |
| and then |
| (Front_End_Inlining |
| or else Configurable_Run_Time_Mode))) |
| then |
| Build_Body_To_Inline (N, Spec_Id); |
| end if; |
| |
| -- Now we can go on to analyze the body |
| |
| HSS := Handled_Statement_Sequence (N); |
| Set_Actual_Subtypes (N, Current_Scope); |
| Analyze_Declarations (Declarations (N)); |
| Check_Completion; |
| Analyze (HSS); |
| Process_End_Label (HSS, 't', Current_Scope); |
| End_Scope; |
| Check_Subprogram_Order (N); |
| |
| -- If we have a separate spec, then the analysis of the declarations |
| -- caused the entities in the body to be chained to the spec id, but |
| -- we want them chained to the body id. Only the formal parameters |
| -- end up chained to the spec id in this case. |
| |
| if Present (Spec_Id) then |
| |
| -- If a parent unit is categorized, the context of a subunit |
| -- must conform to the categorization. Conversely, if a child |
| -- unit is categorized, the parents themselves must conform. |
| |
| if Nkind (Parent (N)) = N_Subunit then |
| Validate_Categorization_Dependency (N, Spec_Id); |
| |
| elsif Is_Child_Unit (Spec_Id) then |
| Validate_Categorization_Dependency |
| (Unit_Declaration_Node (Spec_Id), Spec_Id); |
| end if; |
| |
| if Present (Last_Formal) then |
| Set_Next_Entity |
| (Last_Entity (Body_Id), Next_Entity (Last_Formal)); |
| Set_Next_Entity (Last_Formal, Empty); |
| Set_Last_Entity (Body_Id, Last_Entity (Spec_Id)); |
| Set_Last_Entity (Spec_Id, Last_Formal); |
| |
| else |
| Set_First_Entity (Body_Id, First_Entity (Spec_Id)); |
| Set_Last_Entity (Body_Id, Last_Entity (Spec_Id)); |
| Set_First_Entity (Spec_Id, Empty); |
| Set_Last_Entity (Spec_Id, Empty); |
| end if; |
| end if; |
| |
| -- If function, check return statements |
| |
| if Nkind (Body_Spec) = N_Function_Specification then |
| declare |
| Id : Entity_Id; |
| |
| begin |
| if Present (Spec_Id) then |
| Id := Spec_Id; |
| else |
| Id := Body_Id; |
| end if; |
| |
| if Return_Present (Id) then |
| Check_Returns (HSS, 'F', Missing_Ret); |
| |
| if Missing_Ret then |
| Set_Has_Missing_Return (Id); |
| end if; |
| |
| elsif not Is_Machine_Code_Subprogram (Id) |
| and then not Body_Deleted |
| then |
| Error_Msg_N ("missing RETURN statement in function body", N); |
| end if; |
| end; |
| |
| -- If procedure with No_Return, check returns |
| |
| elsif Nkind (Body_Spec) = N_Procedure_Specification |
| and then Present (Spec_Id) |
| and then No_Return (Spec_Id) |
| then |
| Check_Returns (HSS, 'P', Missing_Ret); |
| end if; |
| |
| -- Now we are going to check for variables that are never modified |
| -- in the body of the procedure. We omit these checks if the first |
| -- statement of the procedure raises an exception. In particular |
| -- this deals with the common idiom of a stubbed function, which |
| -- might appear as something like |
| |
| -- function F (A : Integer) return Some_Type; |
| -- X : Some_Type; |
| -- begin |
| -- raise Program_Error; |
| -- return X; |
| -- end F; |
| |
| -- Here the purpose of X is simply to satisfy the (annoying) |
| -- requirement in Ada that there be at least one return, and |
| -- we certainly do not want to go posting warnings on X that |
| -- it is not initialized! |
| |
| declare |
| Stm : Node_Id := First (Statements (HSS)); |
| |
| begin |
| -- Skip an initial label (for one thing this occurs when we |
| -- are in front end ZCX mode, but in any case it is irrelevant). |
| |
| if Nkind (Stm) = N_Label then |
| Next (Stm); |
| end if; |
| |
| -- Do the test on the original statement before expansion |
| |
| declare |
| Ostm : constant Node_Id := Original_Node (Stm); |
| |
| begin |
| -- If explicit raise statement, return with no checks |
| |
| if Nkind (Ostm) = N_Raise_Statement then |
| return; |
| |
| -- Check for explicit call cases which likely raise an exception |
| |
| elsif Nkind (Ostm) = N_Procedure_Call_Statement then |
| if Is_Entity_Name (Name (Ostm)) then |
| declare |
| Ent : constant Entity_Id := Entity (Name (Ostm)); |
| |
| begin |
| -- If the procedure is marked No_Return, then likely it |
| -- raises an exception, but in any case it is not coming |
| -- back here, so no need to check beyond the call. |
| |
| if Ekind (Ent) = E_Procedure |
| and then No_Return (Ent) |
| then |
| return; |
| |
| -- If the procedure name is Raise_Exception, then also |
| -- assume that it raises an exception. The main target |
| -- here is Ada.Exceptions.Raise_Exception, but this name |
| -- is pretty evocative in any context! Note that the |
| -- procedure in Ada.Exceptions is not marked No_Return |
| -- because of the annoying case of the null exception Id. |
| |
| elsif Chars (Ent) = Name_Raise_Exception then |
| return; |
| end if; |
| end; |
| end if; |
| end if; |
| end; |
| end; |
| |
| -- Check for variables that are never modified |
| |
| declare |
| E1, E2 : Entity_Id; |
| |
| begin |
| -- If there is a separate spec, then transfer Never_Set_In_Source |
| -- flags from out parameters to the corresponding entities in the |
| -- body. The reason we do that is we want to post error flags on |
| -- the body entities, not the spec entities. |
| |
| if Present (Spec_Id) then |
| E1 := First_Entity (Spec_Id); |
| |
| while Present (E1) loop |
| if Ekind (E1) = E_Out_Parameter then |
| E2 := First_Entity (Body_Id); |
| while Present (E2) loop |
| exit when Chars (E1) = Chars (E2); |
| Next_Entity (E2); |
| end loop; |
| |
| if Present (E2) then |
| Set_Never_Set_In_Source (E2, Never_Set_In_Source (E1)); |
| end if; |
| end if; |
| |
| Next_Entity (E1); |
| end loop; |
| end if; |
| |
| -- Check references in body unless it was deleted. Note that the |
| -- check of Body_Deleted here is not just for efficiency, it is |
| -- necessary to avoid junk warnings on formal parameters. |
| |
| if not Body_Deleted then |
| Check_References (Body_Id); |
| end if; |
| end; |
| end Analyze_Subprogram_Body; |
| |
| ------------------------------------ |
| -- Analyze_Subprogram_Declaration -- |
| ------------------------------------ |
| |
| procedure Analyze_Subprogram_Declaration (N : Node_Id) is |
| Designator : constant Entity_Id := |
| Analyze_Subprogram_Specification (Specification (N)); |
| Scop : constant Entity_Id := Current_Scope; |
| |
| -- Start of processing for Analyze_Subprogram_Declaration |
| |
| begin |
| Generate_Definition (Designator); |
| |
| -- Check for RCI unit subprogram declarations against in-lined |
| -- subprograms and subprograms having access parameter or limited |
| -- parameter without Read and Write (RM E.2.3(12-13)). |
| |
| Validate_RCI_Subprogram_Declaration (N); |
| |
| Trace_Scope |
| (N, |
| Defining_Entity (N), |
| " Analyze subprogram spec. "); |
| |
| if Debug_Flag_C then |
| Write_Str ("==== Compiling subprogram spec "); |
| Write_Name (Chars (Designator)); |
| Write_Str (" from "); |
| Write_Location (Sloc (N)); |
| Write_Eol; |
| end if; |
| |
| New_Overloaded_Entity (Designator); |
| Check_Delayed_Subprogram (Designator); |
| |
| -- What is the following code for, it used to be |
| |
| -- ??? Set_Suppress_Elaboration_Checks |
| -- ??? (Designator, Elaboration_Checks_Suppressed (Designator)); |
| |
| -- The following seems equivalent, but a bit dubious |
| |
| if Elaboration_Checks_Suppressed (Designator) then |
| Set_Kill_Elaboration_Checks (Designator); |
| end if; |
| |
| if Scop /= Standard_Standard |
| and then not Is_Child_Unit (Designator) |
| then |
| Set_Categorization_From_Scope (Designator, Scop); |
| else |
| -- For a compilation unit, check for library-unit pragmas. |
| |
| New_Scope (Designator); |
| Set_Categorization_From_Pragmas (N); |
| Validate_Categorization_Dependency (N, Designator); |
| Pop_Scope; |
| end if; |
| |
| -- For a compilation unit, set body required. This flag will only be |
| -- reset if a valid Import or Interface pragma is processed later on. |
| |
| if Nkind (Parent (N)) = N_Compilation_Unit then |
| Set_Body_Required (Parent (N), True); |
| end if; |
| |
| Generate_Reference_To_Formals (Designator); |
| Check_Eliminated (Designator); |
| |
| if Comes_From_Source (N) |
| and then Is_List_Member (N) |
| then |
| Check_Overriding_Operation (N, Designator); |
| end if; |
| |
| end Analyze_Subprogram_Declaration; |
| |
| -------------------------------------- |
| -- Analyze_Subprogram_Specification -- |
| -------------------------------------- |
| |
| -- Reminder: N here really is a subprogram specification (not a subprogram |
| -- declaration). This procedure is called to analyze the specification in |
| -- both subprogram bodies and subprogram declarations (specs). |
| |
| function Analyze_Subprogram_Specification (N : Node_Id) return Entity_Id is |
| Designator : constant Entity_Id := Defining_Entity (N); |
| Formals : constant List_Id := Parameter_Specifications (N); |
| Typ : Entity_Id; |
| |
| begin |
| Generate_Definition (Designator); |
| |
| if Nkind (N) = N_Function_Specification then |
| Set_Ekind (Designator, E_Function); |
| Set_Mechanism (Designator, Default_Mechanism); |
| |
| if Subtype_Mark (N) /= Error then |
| Find_Type (Subtype_Mark (N)); |
| Typ := Entity (Subtype_Mark (N)); |
| Set_Etype (Designator, Typ); |
| |
| if Ekind (Typ) = E_Incomplete_Type |
| or else (Is_Class_Wide_Type (Typ) |
| and then |
| Ekind (Root_Type (Typ)) = E_Incomplete_Type) |
| then |
| Error_Msg_N |
| ("invalid use of incomplete type", Subtype_Mark (N)); |
| end if; |
| |
| else |
| Set_Etype (Designator, Any_Type); |
| end if; |
| |
| else |
| Set_Ekind (Designator, E_Procedure); |
| Set_Etype (Designator, Standard_Void_Type); |
| end if; |
| |
| if Present (Formals) then |
| Set_Scope (Designator, Current_Scope); |
| New_Scope (Designator); |
| Process_Formals (Formals, N); |
| End_Scope; |
| end if; |
| |
| if Nkind (N) = N_Function_Specification then |
| if Nkind (Designator) = N_Defining_Operator_Symbol then |
| Valid_Operator_Definition (Designator); |
| end if; |
| |
| May_Need_Actuals (Designator); |
| |
| if Is_Abstract (Etype (Designator)) |
| and then Nkind (Parent (N)) /= N_Abstract_Subprogram_Declaration |
| then |
| Error_Msg_N |
| ("function that returns abstract type must be abstract", N); |
| end if; |
| end if; |
| |
| return Designator; |
| end Analyze_Subprogram_Specification; |
| |
| -------------------------- |
| -- Build_Body_To_Inline -- |
| -------------------------- |
| |
| procedure Build_Body_To_Inline (N : Node_Id; Subp : Entity_Id) is |
| Decl : constant Node_Id := Unit_Declaration_Node (Subp); |
| Original_Body : Node_Id; |
| Body_To_Analyze : Node_Id; |
| Max_Size : constant := 10; |
| Stat_Count : Integer := 0; |
| |
| function Has_Excluded_Declaration (Decls : List_Id) return Boolean; |
| -- Check for declarations that make inlining not worthwhile. |
| |
| function Has_Excluded_Statement (Stats : List_Id) return Boolean; |
| -- Check for statements that make inlining not worthwhile: any |
| -- tasking statement, nested at any level. Keep track of total |
| -- number of elementary statements, as a measure of acceptable size. |
| |
| function Has_Pending_Instantiation return Boolean; |
| -- If some enclosing body contains instantiations that appear before |
| -- the corresponding generic body, the enclosing body has a freeze node |
| -- so that it can be elaborated after the generic itself. This might |
| -- conflict with subsequent inlinings, so that it is unsafe to try to |
| -- inline in such a case. |
| |
| procedure Remove_Pragmas; |
| -- A pragma Unreferenced that mentions a formal parameter has no |
| -- meaning when the body is inlined and the formals are rewritten. |
| -- Remove it from body to inline. The analysis of the non-inlined |
| -- body will handle the pragma properly. |
| |
| ------------------------------ |
| -- Has_Excluded_Declaration -- |
| ------------------------------ |
| |
| function Has_Excluded_Declaration (Decls : List_Id) return Boolean is |
| D : Node_Id; |
| |
| function Is_Unchecked_Conversion (D : Node_Id) return Boolean; |
| -- Nested subprograms make a given body ineligible for inlining, |
| -- but we make an exception for instantiations of unchecked |
| -- conversion. The body has not been analyzed yet, so we check |
| -- the name, and verify that the visible entity with that name is |
| -- the predefined unit. |
| |
| function Is_Unchecked_Conversion (D : Node_Id) return Boolean is |
| Id : constant Node_Id := Name (D); |
| Conv : Entity_Id; |
| |
| begin |
| if Nkind (Id) = N_Identifier |
| and then Chars (Id) = Name_Unchecked_Conversion |
| then |
| Conv := Current_Entity (Id); |
| |
| elsif Nkind (Id) = N_Selected_Component |
| and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion |
| then |
| Conv := Current_Entity (Selector_Name (Id)); |
| |
| else |
| return False; |
| end if; |
| |
| return |
| Present (Conv) |
| and then Scope (Conv) = Standard_Standard |
| and then Is_Intrinsic_Subprogram (Conv); |
| end Is_Unchecked_Conversion; |
| |
| -- Start of processing for Has_Excluded_Declaration |
| |
| begin |
| D := First (Decls); |
| |
| while Present (D) loop |
| if (Nkind (D) = N_Function_Instantiation |
| and then not Is_Unchecked_Conversion (D)) |
| or else Nkind (D) = N_Protected_Type_Declaration |
| or else Nkind (D) = N_Package_Declaration |
| or else Nkind (D) = N_Package_Instantiation |
| or else Nkind (D) = N_Subprogram_Body |
| or else Nkind (D) = N_Procedure_Instantiation |
| or else Nkind (D) = N_Task_Type_Declaration |
| then |
| Cannot_Inline |
| ("cannot inline & (non-allowed declaration)?", D, Subp); |
| return True; |
| end if; |
| |
| Next (D); |
| end loop; |
| |
| return False; |
| end Has_Excluded_Declaration; |
| |
| ---------------------------- |
| -- Has_Excluded_Statement -- |
| ---------------------------- |
| |
| function Has_Excluded_Statement (Stats : List_Id) return Boolean is |
| S : Node_Id; |
| E : Node_Id; |
| |
| begin |
| S := First (Stats); |
| |
| while Present (S) loop |
| Stat_Count := Stat_Count + 1; |
| |
| if Nkind (S) = N_Abort_Statement |
| or else Nkind (S) = N_Asynchronous_Select |
| or else Nkind (S) = N_Conditional_Entry_Call |
| or else Nkind (S) = N_Delay_Relative_Statement |
| or else Nkind (S) = N_Delay_Until_Statement |
| or else Nkind (S) = N_Selective_Accept |
| or else Nkind (S) = N_Timed_Entry_Call |
| then |
| Cannot_Inline |
| ("cannot inline & (non-allowed statement)?", S, Subp); |
| return True; |
| |
| elsif Nkind (S) = N_Block_Statement then |
| if Present (Declarations (S)) |
| and then Has_Excluded_Declaration (Declarations (S)) |
| then |
| return True; |
| |
| elsif Present (Handled_Statement_Sequence (S)) |
| and then |
| (Present |
| (Exception_Handlers (Handled_Statement_Sequence (S))) |
| or else |
| Has_Excluded_Statement |
| (Statements (Handled_Statement_Sequence (S)))) |
| then |
| return True; |
| end if; |
| |
| elsif Nkind (S) = N_Case_Statement then |
| E := First (Alternatives (S)); |
| |
| while Present (E) loop |
| if Has_Excluded_Statement (Statements (E)) then |
| return True; |
| end if; |
| |
| Next (E); |
| end loop; |
| |
| elsif Nkind (S) = N_If_Statement then |
| if Has_Excluded_Statement (Then_Statements (S)) then |
| return True; |
| end if; |
| |
| if Present (Elsif_Parts (S)) then |
| E := First (Elsif_Parts (S)); |
| |
| while Present (E) loop |
| if Has_Excluded_Statement (Then_Statements (E)) then |
| return True; |
| end if; |
| Next (E); |
| end loop; |
| end if; |
| |
| if Present (Else_Statements (S)) |
| and then Has_Excluded_Statement (Else_Statements (S)) |
| then |
| return True; |
| end if; |
| |
| elsif Nkind (S) = N_Loop_Statement |
| and then Has_Excluded_Statement (Statements (S)) |
| then |
| return True; |
| end if; |
| |
| Next (S); |
| end loop; |
| |
| return False; |
| end Has_Excluded_Statement; |
| |
| ------------------------------- |
| -- Has_Pending_Instantiation -- |
| ------------------------------- |
| |
| function Has_Pending_Instantiation return Boolean is |
| S : Entity_Id := Current_Scope; |
| |
| begin |
| while Present (S) loop |
| if Is_Compilation_Unit (S) |
| or else Is_Child_Unit (S) |
| then |
| return False; |
| elsif Ekind (S) = E_Package |
| and then Has_Forward_Instantiation (S) |
| then |
| return True; |
| end if; |
| |
| S := Scope (S); |
| end loop; |
| |
| return False; |
| end Has_Pending_Instantiation; |
| |
| -------------------- |
| -- Remove_Pragmas -- |
| -------------------- |
| |
| procedure Remove_Pragmas is |
| Decl : Node_Id; |
| Nxt : Node_Id; |
| |
| begin |
| Decl := First (Declarations (Body_To_Analyze)); |
| while Present (Decl) loop |
| Nxt := Next (Decl); |
| |
| if Nkind (Decl) = N_Pragma |
| and then Chars (Decl) = Name_Unreferenced |
| then |
| Remove (Decl); |
| end if; |
| |
| Decl := Nxt; |
| end loop; |
| end Remove_Pragmas; |
| |
| -- Start of processing for Build_Body_To_Inline |
| |
| begin |
| if Nkind (Decl) = N_Subprogram_Declaration |
| and then Present (Body_To_Inline (Decl)) |
| then |
| return; -- Done already. |
| |
| -- Functions that return unconstrained composite types will require |
| -- secondary stack handling, and cannot currently be inlined. |
| |
| elsif Ekind (Subp) = E_Function |
| and then not Is_Scalar_Type (Etype (Subp)) |
| and then not Is_Access_Type (Etype (Subp)) |
| and then not Is_Constrained (Etype (Subp)) |
| then |
| Cannot_Inline |
| ("cannot inline & (unconstrained return type)?", N, Subp); |
| return; |
| end if; |
| |
| if Present (Declarations (N)) |
| and then Has_Excluded_Declaration (Declarations (N)) |
| then |
| return; |
| end if; |
| |
| if Present (Handled_Statement_Sequence (N)) then |
| if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then |
| Cannot_Inline |
| ("cannot inline& (exception handler)?", |
| First (Exception_Handlers (Handled_Statement_Sequence (N))), |
| Subp); |
| return; |
| elsif |
| Has_Excluded_Statement |
| (Statements (Handled_Statement_Sequence (N))) |
| then |
| return; |
| end if; |
| end if; |
| |
| -- We do not inline a subprogram that is too large, unless it is |
| -- marked Inline_Always. This pragma does not suppress the other |
| -- checks on inlining (forbidden declarations, handlers, etc). |
| |
| if Stat_Count > Max_Size |
| and then not Is_Always_Inlined (Subp) |
| then |
| Cannot_Inline ("cannot inline& (body too large)?", N, Subp); |
| return; |
| end if; |
| |
| if Has_Pending_Instantiation then |
| Cannot_Inline |
| ("cannot inline& (forward instance within enclosing body)?", |
| N, Subp); |
| return; |
| end if; |
| |
| -- Within an instance, the body to inline must be treated as a nested |
| -- generic, so that the proper global references are preserved. |
| |
| if In_Instance then |
| Save_Env (Scope (Current_Scope), Scope (Current_Scope)); |
| Original_Body := Copy_Generic_Node (N, Empty, True); |
| else |
| Original_Body := Copy_Separate_Tree (N); |
| end if; |
| |
| -- We need to capture references to the formals in order to substitute |
| -- the actuals at the point of inlining, i.e. instantiation. To treat |
| -- the formals as globals to the body to inline, we nest it within |
| -- a dummy parameterless subprogram, declared within the real one. |
| |
| Set_Parameter_Specifications (Specification (Original_Body), No_List); |
| Set_Defining_Unit_Name (Specification (Original_Body), |
| Make_Defining_Identifier (Sloc (N), New_Internal_Name ('S'))); |
| Set_Corresponding_Spec (Original_Body, Empty); |
| |
| Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, False); |
| |
| -- Set return type of function, which is also global and does not need |
| -- to be resolved. |
| |
| if Ekind (Subp) = E_Function then |
| Set_Subtype_Mark (Specification (Body_To_Analyze), |
| New_Occurrence_Of (Etype (Subp), Sloc (N))); |
| end if; |
| |
| if No (Declarations (N)) then |
| Set_Declarations (N, New_List (Body_To_Analyze)); |
| else |
| Append (Body_To_Analyze, Declarations (N)); |
| end if; |
| |
| Expander_Mode_Save_And_Set (False); |
| Remove_Pragmas; |
| |
| Analyze (Body_To_Analyze); |
| New_Scope (Defining_Entity (Body_To_Analyze)); |
| Save_Global_References (Original_Body); |
| End_Scope; |
| Remove (Body_To_Analyze); |
| |
| Expander_Mode_Restore; |
| Set_Body_To_Inline (Decl, Original_Body); |
| Set_Ekind (Defining_Entity (Original_Body), Ekind (Subp)); |
| Set_Is_Inlined (Subp); |
| |
| if In_Instance then |
| Restore_Env; |
| end if; |
| end Build_Body_To_Inline; |
| |
| ------------------- |
| -- Cannot_Inline -- |
| ------------------- |
| |
| procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id) is |
| begin |
| -- Do not emit warning if this is a predefined unit which is not |
| -- the main unit. With validity checks enabled, some predefined |
| -- subprograms may contain nested subprograms and become ineligible |
| -- for inlining. |
| |
| if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Subp))) |
| and then not In_Extended_Main_Source_Unit (Subp) |
| then |
| null; |
| |
| elsif Is_Always_Inlined (Subp) then |
| Error_Msg_NE (Msg (1 .. Msg'Length - 1), N, Subp); |
| |
| elsif Ineffective_Inline_Warnings then |
| Error_Msg_NE (Msg, N, Subp); |
| end if; |
| end Cannot_Inline; |
| |
| ----------------------- |
| -- Check_Conformance -- |
| ----------------------- |
| |
| procedure Check_Conformance |
| (New_Id : Entity_Id; |
| Old_Id : Entity_Id; |
| Ctype : Conformance_Type; |
| Errmsg : Boolean; |
| Conforms : out Boolean; |
| Err_Loc : Node_Id := Empty; |
| Get_Inst : Boolean := False) |
| is |
| Old_Type : constant Entity_Id := Etype (Old_Id); |
| New_Type : constant Entity_Id := Etype (New_Id); |
| Old_Formal : Entity_Id; |
| New_Formal : Entity_Id; |
| |
| procedure Conformance_Error (Msg : String; N : Node_Id := New_Id); |
| -- Post error message for conformance error on given node. |
| -- Two messages are output. The first points to the previous |
| -- declaration with a general "no conformance" message. |
| -- The second is the detailed reason, supplied as Msg. The |
| -- parameter N provide information for a possible & insertion |
| -- in the message, and also provides the location for posting |
| -- the message in the absence of a specified Err_Loc location. |
| |
| ----------------------- |
| -- Conformance_Error -- |
| ----------------------- |
| |
| procedure Conformance_Error (Msg : String; N : Node_Id := New_Id) is |
| Enode : Node_Id; |
| |
| begin |
| Conforms := False; |
| |
| if Errmsg then |
| if No (Err_Loc) then |
| Enode := N; |
| else |
| Enode := Err_Loc; |
| end if; |
| |
| Error_Msg_Sloc := Sloc (Old_Id); |
| |
| case Ctype is |
| when Type_Conformant => |
| Error_Msg_N |
| ("not type conformant with declaration#!", Enode); |
| |
| when Mode_Conformant => |
| Error_Msg_N |
| ("not mode conformant with declaration#!", Enode); |
| |
| when Subtype_Conformant => |
| Error_Msg_N |
| ("not subtype conformant with declaration#!", Enode); |
| |
| when Fully_Conformant => |
| Error_Msg_N |
| ("not fully conformant with declaration#!", Enode); |
| end case; |
| |
| Error_Msg_NE (Msg, Enode, N); |
| end if; |
| end Conformance_Error; |
| |
| -- Start of processing for Check_Conformance |
| |
| begin |
| Conforms := True; |
| |
| -- We need a special case for operators, since they don't |
| -- appear explicitly. |
| |
| if Ctype = Type_Conformant then |
| if Ekind (New_Id) = E_Operator |
| and then Operator_Matches_Spec (New_Id, Old_Id) |
| then |
| return; |
| end if; |
| end if; |
| |
| -- If both are functions/operators, check return types conform |
| |
| if Old_Type /= Standard_Void_Type |
| and then New_Type /= Standard_Void_Type |
| then |
| if not Conforming_Types (Old_Type, New_Type, Ctype, Get_Inst) then |
| Conformance_Error ("return type does not match!", New_Id); |
| return; |
| end if; |
| |
| -- If either is a function/operator and the other isn't, error |
| |
| elsif Old_Type /= Standard_Void_Type |
| or else New_Type /= Standard_Void_Type |
| then |
| Conformance_Error ("functions can only match functions!", New_Id); |
| return; |
| end if; |
| |
| -- In subtype conformant case, conventions must match (RM 6.3.1(16)) |
| -- If this is a renaming as body, refine error message to indicate that |
| -- the conflict is with the original declaration. If the entity is not |
| -- frozen, the conventions don't have to match, the one of the renamed |
| -- entity is inherited. |
| |
| if Ctype >= Subtype_Conformant then |
| if Convention (Old_Id) /= Convention (New_Id) then |
| |
| if not Is_Frozen (New_Id) then |
| null; |
| |
| elsif Present (Err_Loc) |
| and then Nkind (Err_Loc) = N_Subprogram_Renaming_Declaration |
| and then Present (Corresponding_Spec (Err_Loc)) |
| then |
| Error_Msg_Name_1 := Chars (New_Id); |
| Error_Msg_Name_2 := |
| Name_Ada + Convention_Id'Pos (Convention (New_Id)); |
| |
| Conformance_Error ("prior declaration for% has convention %!"); |
| |
| else |
| Conformance_Error ("calling conventions do not match!"); |
| end if; |
| |
| return; |
| |
| elsif Is_Formal_Subprogram (Old_Id) |
| or else Is_Formal_Subprogram (New_Id) |
| then |
| Conformance_Error ("formal subprograms not allowed!"); |
| return; |
| end if; |
| end if; |
| |
| -- Deal with parameters |
| |
| -- Note: we use the entity information, rather than going directly |
| -- to the specification in the tree. This is not only simpler, but |
| -- absolutely necessary for some cases of conformance tests between |
| -- operators, where the declaration tree simply does not exist! |
| |
| Old_Formal := First_Formal (Old_Id); |
| New_Formal := First_Formal (New_Id); |
| |
| while Present (Old_Formal) and then Present (New_Formal) loop |
| if Ctype = Fully_Conformant then |
| |
| -- Names must match. Error message is more accurate if we do |
| -- this before checking that the types of the formals match. |
| |
| if Chars (Old_Formal) /= Chars (New_Formal) then |
| Conformance_Error ("name & does not match!", New_Formal); |
| |
| -- Set error posted flag on new formal as well to stop |
| -- junk cascaded messages in some cases. |
| |
| Set_Error_Posted (New_Formal); |
| return; |
| end if; |
| end if; |
| |
| -- Types must always match. In the visible part of an instance, |
| -- usual overloading rules for dispatching operations apply, and |
| -- we check base types (not the actual subtypes). |
| |
| if In_Instance_Visible_Part |
| and then Is_Dispatching_Operation (New_Id) |
| then |
| if not Conforming_Types |
| (Base_Type (Etype (Old_Formal)), |
| Base_Type (Etype (New_Formal)), Ctype, Get_Inst) |
| then |
| Conformance_Error ("type of & does not match!", New_Formal); |
| return; |
| end if; |
| |
| elsif not Conforming_Types |
| (Etype (Old_Formal), Etype (New_Formal), Ctype, Get_Inst) |
| then |
| Conformance_Error ("type of & does not match!", New_Formal); |
| return; |
| end if; |
| |
| -- For mode conformance, mode must match |
| |
| if Ctype >= Mode_Conformant |
| and then Parameter_Mode (Old_Formal) /= Parameter_Mode (New_Formal) |
| then |
| Conformance_Error ("mode of & does not match!", New_Formal); |
| return; |
| end if; |
| |
| -- Full conformance checks |
| |
| if Ctype = Fully_Conformant then |
| |
| -- We have checked already that names match. |
| -- Check default expressions for in parameters |
| |
| if Parameter_Mode (Old_Formal) = E_In_Parameter then |
| declare |
| NewD : constant Boolean := |
| Present (Default_Value (New_Formal)); |
| OldD : constant Boolean := |
| Present (Default_Value (Old_Formal)); |
| begin |
| if NewD or OldD then |
| |
| -- The old default value has been analyzed because |
| -- the current full declaration will have frozen |
| -- everything before. The new default values have not |
| -- been analyzed, so analyze them now before we check |
| -- for conformance. |
| |
| if NewD then |
| New_Scope (New_Id); |
| Analyze_Per_Use_Expression |
| (Default_Value (New_Formal), Etype (New_Formal)); |
| End_Scope; |
| end if; |
| |
| if not (NewD and OldD) |
| or else not Fully_Conformant_Expressions |
| (Default_Value (Old_Formal), |
| Default_Value (New_Formal)) |
| then |
| Conformance_Error |
| ("default expression for & does not match!", |
| New_Formal); |
| return; |
| end if; |
| end if; |
| end; |
| end if; |
| end if; |
| |
| -- A couple of special checks for Ada 83 mode. These checks are |
| -- skipped if either entity is an operator in package Standard. |
| -- or if either old or new instance is not from the source program. |
| |
| if Ada_83 |
| and then Sloc (Old_Id) > Standard_Location |
| and then Sloc (New_Id) > Standard_Location |
| and then Comes_From_Source (Old_Id) |
| and then Comes_From_Source (New_Id) |
| then |
| declare |
| Old_Param : constant Node_Id := Declaration_Node (Old_Formal); |
| New_Param : constant Node_Id := Declaration_Node (New_Formal); |
| |
| begin |
| -- Explicit IN must be present or absent in both cases. This |
| -- test is required only in the full conformance case. |
| |
| if In_Present (Old_Param) /= In_Present (New_Param) |
| and then Ctype = Fully_Conformant |
| then |
| Conformance_Error |
| ("(Ada 83) IN must appear in both declarations", |
| New_Formal); |
| return; |
| end if; |
| |
| -- Grouping (use of comma in param lists) must be the same |
| -- This is where we catch a misconformance like: |
| |
| -- A,B : Integer |
| -- A : Integer; B : Integer |
| |
| -- which are represented identically in the tree except |
| -- for the setting of the flags More_Ids and Prev_Ids. |
| |
| if More_Ids (Old_Param) /= More_Ids (New_Param) |
| or else Prev_Ids (Old_Param) /= Prev_Ids (New_Param) |
| then |
| Conformance_Error |
| ("grouping of & does not match!", New_Formal); |
| return; |
| end if; |
| end; |
| end if; |
| |
| Next_Formal (Old_Formal); |
| Next_Formal (New_Formal); |
| end loop; |
| |
| if Present (Old_Formal) then |
| Conformance_Error ("too few parameters!"); |
| return; |
| |
| elsif Present (New_Formal) then |
| Conformance_Error ("too many parameters!", New_Formal); |
| return; |
| end if; |
| |
| end Check_Conformance; |
| |
| ------------------------------ |
| -- Check_Delayed_Subprogram -- |
| ------------------------------ |
| |
| procedure Check_Delayed_Subprogram (Designator : Entity_Id) is |
| F : Entity_Id; |
| |
| procedure Possible_Freeze (T : Entity_Id); |
| -- T is the type of either a formal parameter or of the return type. |
| -- If T is not yet frozen and needs a delayed freeze, then the |
| -- subprogram itself must be delayed. |
| |
| procedure Possible_Freeze (T : Entity_Id) is |
| begin |
| if Has_Delayed_Freeze (T) |
| and then not Is_Frozen (T) |
| then |
| Set_Has_Delayed_Freeze (Designator); |
| |
| elsif Is_Access_Type (T) |
| and then Has_Delayed_Freeze (Designated_Type (T)) |
| and then not Is_Frozen (Designated_Type (T)) |
| then |
| Set_Has_Delayed_Freeze (Designator); |
| end if; |
| end Possible_Freeze; |
| |
| -- Start of processing for Check_Delayed_Subprogram |
| |
| begin |
| -- Never need to freeze abstract subprogram |
| |
| if Is_Abstract (Designator) then |
| null; |
| else |
| -- Need delayed freeze if return type itself needs a delayed |
| -- freeze and is not yet frozen. |
| |
| Possible_Freeze (Etype (Designator)); |
| Possible_Freeze (Base_Type (Etype (Designator))); -- needed ??? |
| |
| -- Need delayed freeze if any of the formal types themselves need |
| -- a delayed freeze and are not yet frozen. |
| |
| F := First_Formal (Designator); |
| while Present (F) loop |
| Possible_Freeze (Etype (F)); |
| Possible_Freeze (Base_Type (Etype (F))); -- needed ??? |
| Next_Formal (F); |
| end loop; |
| end if; |
| |
| -- Mark functions that return by reference. Note that it cannot be |
| -- done for delayed_freeze subprograms because the underlying |
| -- returned type may not be known yet (for private types) |
| |
| if not Has_Delayed_Freeze (Designator) |
| and then Expander_Active |
| then |
| declare |
| Typ : constant Entity_Id := Etype (Designator); |
| Utyp : constant Entity_Id := Underlying_Type (Typ); |
| |
| begin |
| if Is_Return_By_Reference_Type (Typ) then |
| Set_Returns_By_Ref (Designator); |
| |
| elsif Present (Utyp) and then Controlled_Type (Utyp) then |
| Set_Returns_By_Ref (Designator); |
| end if; |
| end; |
| end if; |
| end Check_Delayed_Subprogram; |
| |
| ------------------------------------ |
| -- Check_Discriminant_Conformance -- |
| ------------------------------------ |
| |
| procedure Check_Discriminant_Conformance |
| (N : Node_Id; |
| Prev : Entity_Id; |
| Prev_Loc : Node_Id) |
| is |
| Old_Discr : Entity_Id := First_Discriminant (Prev); |
| New_Discr : Node_Id := First (Discriminant_Specifications (N)); |
| New_Discr_Id : Entity_Id; |
| New_Discr_Type : Entity_Id; |
| |
| procedure Conformance_Error (Msg : String; N : Node_Id); |
| -- Post error message for conformance error on given node. |
| -- Two messages are output. The first points to the previous |
| -- declaration with a general "no conformance" message. |
| -- The second is the detailed reason, supplied as Msg. The |
| -- parameter N provide information for a possible & insertion |
| -- in the message. |
| |
| ----------------------- |
| -- Conformance_Error -- |
| ----------------------- |
| |
| procedure Conformance_Error (Msg : String; N : Node_Id) is |
| begin |
| Error_Msg_Sloc := Sloc (Prev_Loc); |
| Error_Msg_N ("not fully conformant with declaration#!", N); |
| Error_Msg_NE (Msg, N, N); |
| end Conformance_Error; |
| |
| -- Start of processing for Check_Discriminant_Conformance |
| |
| begin |
| while Present (Old_Discr) and then Present (New_Discr) loop |
| |
| New_Discr_Id := Defining_Identifier (New_Discr); |
| |
| -- The subtype mark of the discriminant on the full type |
| -- has not been analyzed so we do it here. For an access |
| -- discriminant a new type is created. |
| |
| if Nkind (Discriminant_Type (New_Discr)) = N_Access_Definition then |
| New_Discr_Type := |
| Access_Definition (N, Discriminant_Type (New_Discr)); |
| |
| else |
| Analyze (Discriminant_Type (New_Discr)); |
| New_Discr_Type := Etype (Discriminant_Type (New_Discr)); |
| end if; |
| |
| if not Conforming_Types |
| (Etype (Old_Discr), New_Discr_Type, Fully_Conformant) |
| then |
| Conformance_Error ("type of & does not match!", New_Discr_Id); |
| return; |
| else |
| -- Treat the new discriminant as an occurrence of the old |
| -- one, for navigation purposes, and fill in some semantic |
| -- information, for completeness. |
| |
| Generate_Reference (Old_Discr, New_Discr_Id, 'r'); |
| Set_Etype (New_Discr_Id, Etype (Old_Discr)); |
| Set_Scope (New_Discr_Id, Scope (Old_Discr)); |
| end if; |
| |
| -- Names must match |
| |
| if Chars (Old_Discr) /= Chars (Defining_Identifier (New_Discr)) then |
| Conformance_Error ("name & does not match!", New_Discr_Id); |
| return; |
| end if; |
| |
| -- Default expressions must match |
| |
| declare |
| NewD : constant Boolean := |
| Present (Expression (New_Discr)); |
| OldD : constant Boolean := |
| Present (Expression (Parent (Old_Discr))); |
| |
| begin |
| if NewD or OldD then |
| |
| -- The old default value has been analyzed and expanded, |
| -- because the current full declaration will have frozen |
| -- everything before. The new default values have not |
| -- been expanded, so expand now to check conformance. |
| |
| if NewD then |
| Analyze_Per_Use_Expression |
| (Expression (New_Discr), New_Discr_Type); |
| end if; |
| |
| if not (NewD and OldD) |
| or else not Fully_Conformant_Expressions |
| (Expression (Parent (Old_Discr)), |
| Expression (New_Discr)) |
| |
| then |
| Conformance_Error |
| ("default expression for & does not match!", |
| New_Discr_Id); |
| return; |
| end if; |
| end if; |
| end; |
| |
| -- In Ada 83 case, grouping must match: (A,B : X) /= (A : X; B : X) |
| |
| if Ada_83 then |
| declare |
| Old_Disc : constant Node_Id := Declaration_Node (Old_Discr); |
| |
| begin |
| -- Grouping (use of comma in param lists) must be the same |
| -- This is where we catch a misconformance like: |
| |
| -- A,B : Integer |
| -- A : Integer; B : Integer |
| |
| -- which are represented identically in the tree except |
| -- for the setting of the flags More_Ids and Prev_Ids. |
| |
| if More_Ids (Old_Disc) /= More_Ids (New_Discr) |
| or else Prev_Ids (Old_Disc) /= Prev_Ids (New_Discr) |
| then |
| Conformance_Error |
| ("grouping of & does not match!", New_Discr_Id); |
| return; |
| end if; |
| end; |
| end if; |
| |
| Next_Discriminant (Old_Discr); |
| Next (New_Discr); |
| end loop; |
| |
| if Present (Old_Discr) then |
| Conformance_Error ("too few discriminants!", Defining_Identifier (N)); |
| return; |
| |
| elsif Present (New_Discr) then |
| Conformance_Error |
| ("too many discriminants!", Defining_Identifier (New_Discr)); |
| return; |
| end if; |
| end Check_Discriminant_Conformance; |
| |
| ---------------------------- |
| -- Check_Fully_Conformant -- |
| ---------------------------- |
| |
| procedure Check_Fully_Conformant |
| (New_Id : Entity_Id; |
| Old_Id : Entity_Id; |
| Err_Loc : Node_Id := Empty) |
| is |
| Result : Boolean; |
| |
| begin |
| Check_Conformance |
| (New_Id, Old_Id, Fully_Conformant, True, Result, Err_Loc); |
| end Check_Fully_Conformant; |
| |
| --------------------------- |
| -- Check_Mode_Conformant -- |
| --------------------------- |
| |
| procedure Check_Mode_Conformant |
| (New_Id : Entity_Id; |
| Old_Id : Entity_Id; |
| Err_Loc : Node_Id := Empty; |
| Get_Inst : Boolean := False) |
| is |
| Result : Boolean; |
| |
| begin |
| Check_Conformance |
| (New_Id, Old_Id, Mode_Conformant, True, Result, Err_Loc, Get_Inst); |
| end Check_Mode_Conformant; |
| |
| -------------------------------- |
| -- Check_Overriding_Operation -- |
| -------------------------------- |
| |
| procedure Check_Overriding_Operation |
| (N : Node_Id; |
| Subp : Entity_Id) |
| is |
| Arg1 : Node_Id; |
| Decl : Node_Id; |
| Has_Pragma : Boolean := False; |
| |
| begin |
| -- See whether there is an overriding pragma immediately following |
| -- the declaration. Intervening pragmas, such as Inline, are allowed. |
| |
| Decl := Next (N); |
| while Present (Decl) |
| and then Nkind (Decl) = N_Pragma |
| loop |
| if Chars (Decl) = Name_Overriding |
| or else Chars (Decl) = Name_Optional_Overriding |
| then |
| -- For now disable the use of these pragmas, until the ARG |
| -- finalizes the design of this feature. |
| |
| Error_Msg_N ("?unrecognized pragma", Decl); |
| |
| if not Is_Overriding_Operation (Subp) then |
| |
| -- Before emitting an error message, check whether this |
| -- may override an operation that is not yet visible, as |
| -- in the case of a derivation of a private operation in |
| -- a child unit. Such an operation is introduced with a |
| -- different name, but its alias is the parent operation. |
| |
| declare |
| E : Entity_Id; |
| |
| begin |
| E := First_Entity (Current_Scope); |
| |
| while Present (E) loop |
| if Ekind (E) = Ekind (Subp) |
| and then not Comes_From_Source (E) |
| and then Present (Alias (E)) |
| and then Chars (Alias (E)) = Chars (Subp) |
| and then In_Open_Scopes (Scope (Alias (E))) |
| then |
| exit; |
| else |
| Next_Entity (E); |
| end if; |
| end loop; |
| |
| if No (E) then |
| Error_Msg_NE |
| ("& must override an inherited operation", |
| Decl, Subp); |
| end if; |
| end; |
| end if; |
| |
| -- Verify syntax of pragma |
| |
| Arg1 := First (Pragma_Argument_Associations (Decl)); |
| |
| if Present (Arg1) then |
| if not Is_Entity_Name (Expression (Arg1)) then |
| Error_Msg_N ("pragma applies to local subprogram", Decl); |
| |
| elsif Chars (Expression (Arg1)) /= Chars (Subp) then |
| Error_Msg_N |
| ("pragma must apply to preceding subprogram", Decl); |
| |
| elsif Present (Next (Arg1)) then |
| Error_Msg_N ("illegal pragma format", Decl); |
| end if; |
| end if; |
| |
| Set_Analyzed (Decl); |
| Has_Pragma := True; |
| exit; |
| end if; |
| |
| Next (Decl); |
| end loop; |
| |
| if not Has_Pragma |
| and then Explicit_Overriding |
| and then Is_Overriding_Operation (Subp) |
| then |
| Error_Msg_NE ("Missing overriding pragma for&", Subp, Subp); |
| end if; |
| end Check_Overriding_Operation; |
| |
| ------------------- |
| -- Check_Returns -- |
| ------------------- |
| |
| procedure Check_Returns |
| (HSS : Node_Id; |
| Mode : Character; |
| Err : out Boolean) |
| is |
| Handler : Node_Id; |
| |
| procedure Check_Statement_Sequence (L : List_Id); |
| -- Internal recursive procedure to check a list of statements for proper |
| -- termination by a return statement (or a transfer of control or a |
| -- compound statement that is itself internally properly terminated). |
| |
| ------------------------------ |
| -- Check_Statement_Sequence -- |
| ------------------------------ |
| |
| procedure Check_Statement_Sequence (L : List_Id) is |
| Last_Stm : Node_Id; |
| Kind : Node_Kind; |
| |
| Raise_Exception_Call : Boolean; |
| -- Set True if statement sequence terminated by Raise_Exception call |
| -- or a Reraise_Occurrence call. |
| |
| begin |
| Raise_Exception_Call := False; |
| |
| -- Get last real statement |
| |
| Last_Stm := Last (L); |
| |
| -- Don't count pragmas |
| |
| while Nkind (Last_Stm) = N_Pragma |
| |
| -- Don't count call to SS_Release (can happen after Raise_Exception) |
| |
| or else |
| (Nkind (Last_Stm) = N_Procedure_Call_Statement |
| and then |
| Nkind (Name (Last_Stm)) = N_Identifier |
| and then |
| Is_RTE (Entity (Name (Last_Stm)), RE_SS_Release)) |
| |
| -- Don't count exception junk |
| |
| or else |
| ((Nkind (Last_Stm) = N_Goto_Statement |
| or else Nkind (Last_Stm) = N_Label |
| or else Nkind (Last_Stm) = N_Object_Declaration) |
| and then Exception_Junk (Last_Stm)) |
| loop |
| Prev (Last_Stm); |
| end loop; |
| |
| -- Here we have the "real" last statement |
| |
| Kind := Nkind (Last_Stm); |
| |
| -- Transfer of control, OK. Note that in the No_Return procedure |
| -- case, we already diagnosed any explicit return statements, so |
| -- we can treat them as OK in this context. |
| |
| if Is_Transfer (Last_Stm) then |
| return; |
| |
| -- Check cases of explicit non-indirect procedure calls |
| |
| elsif Kind = N_Procedure_Call_Statement |
| and then Is_Entity_Name (Name (Last_Stm)) |
| then |
| -- Check call to Raise_Exception procedure which is treated |
| -- specially, as is a call to Reraise_Occurrence. |
| |
| -- We suppress the warning in these cases since it is likely that |
| -- the programmer really does not expect to deal with the case |
| -- of Null_Occurrence, and thus would find a warning about a |
| -- missing return curious, and raising Program_Error does not |
| -- seem such a bad behavior if this does occur. |
| |
| if Is_RTE (Entity (Name (Last_Stm)), RE_Raise_Exception) |
| or else |
| Is_RTE (Entity (Name (Last_Stm)), RE_Reraise_Occurrence) |
| then |
| Raise_Exception_Call := True; |
| |
| -- For Raise_Exception call, test first argument, if it is |
| -- an attribute reference for a 'Identity call, then we know |
| -- that the call cannot possibly return. |
| |
| declare |
| Arg : constant Node_Id := |
| Original_Node (First_Actual (Last_Stm)); |
| |
| begin |
| if Nkind (Arg) = N_Attribute_Reference |
| and then Attribute_Name (Arg) = Name_Identity |
| then |
| return; |
| end if; |
| end; |
| end if; |
| |
| -- If statement, need to look inside if there is an else and check |
| -- each constituent statement sequence for proper termination. |
| |
| elsif Kind = N_If_Statement |
| and then Present (Else_Statements (Last_Stm)) |
| then |
| Check_Statement_Sequence (Then_Statements (Last_Stm)); |
| Check_Statement_Sequence (Else_Statements (Last_Stm)); |
| |
| if Present (Elsif_Parts (Last_Stm)) then |
| declare |
| Elsif_Part : Node_Id := First (Elsif_Parts (Last_Stm)); |
| |
| begin |
| while Present (Elsif_Part) loop |
| Check_Statement_Sequence (Then_Statements (Elsif_Part)); |
| Next (Elsif_Part); |
| end loop; |
| end; |
| end if; |
| |
| return; |
| |
| -- Case statement, check each case for proper termination |
| |
| elsif Kind = N_Case_Statement then |
| declare |
| Case_Alt : Node_Id; |
| |
| begin |
| Case_Alt := First_Non_Pragma (Alternatives (Last_Stm)); |
| while Present (Case_Alt) loop |
| Check_Statement_Sequence (Statements (Case_Alt)); |
| Next_Non_Pragma (Case_Alt); |
| end loop; |
| end; |
| |
| return; |
| |
| -- Block statement, check its handled sequence of statements |
| |
| elsif Kind = N_Block_Statement then |
| declare |
| Err1 : Boolean; |
| |
| begin |
| Check_Returns |
| (Handled_Statement_Sequence (Last_Stm), Mode, Err1); |
| |
| if Err1 then |
| Err := True; |
| end if; |
| |
| return; |
| end; |
| |
| -- Loop statement. If there is an iteration scheme, we can definitely |
| -- fall out of the loop. Similarly if there is an exit statement, we |
| -- can fall out. In either case we need a following return. |
| |
| elsif Kind = N_Loop_Statement then |
| if Present (Iteration_Scheme (Last_Stm)) |
| or else Has_Exit (Entity (Identifier (Last_Stm))) |
| then |
| null; |
| |
| -- A loop with no exit statement or iteration scheme if either |
| -- an inifite loop, or it has some other exit (raise/return). |
| -- In either case, no warning is required. |
| |
| else |
| return; |
| end if; |
| |
| -- Timed entry call, check entry call and delay alternatives |
| |
| -- Note: in expanded code, the timed entry call has been converted |
| -- to a set of expanded statements on which the check will work |
| -- correctly in any case. |
| |
| elsif Kind = N_Timed_Entry_Call then |
| declare |
| ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm); |
| DCA : constant Node_Id := Delay_Alternative (Last_Stm); |
| |
| begin |
| -- If statement sequence of entry call alternative is missing, |
| -- then we can definitely fall through, and we post the error |
| -- message on the entry call alternative itself. |
| |
| if No (Statements (ECA)) then |
| Last_Stm := ECA; |
| |
| -- If statement sequence of delay alternative is missing, then |
| -- we can definitely fall through, and we post the error |
| -- message on the delay alternative itself. |
| |
| -- Note: if both ECA and DCA are missing the return, then we |
| -- post only one message, should be enough to fix the bugs. |
| -- If not we will get a message next time on the DCA when the |
| -- ECA is fixed! |
| |
| elsif No (Statements (DCA)) then |
| Last_Stm := DCA; |
| |
| -- Else check both statement sequences |
| |
| else |
| Check_Statement_Sequence (Statements (ECA)); |
| Check_Statement_Sequence (Statements (DCA)); |
| return; |
| end if; |
| end; |
| |
| -- Conditional entry call, check entry call and else part |
| |
| -- Note: in expanded code, the conditional entry call has been |
| -- converted to a set of expanded statements on which the check |
| -- will work correctly in any case. |
| |
| elsif Kind = N_Conditional_Entry_Call then |
| declare |
| ECA : constant Node_Id := Entry_Call_Alternative (Last_Stm); |
| |
| begin |
| -- If statement sequence of entry call alternative is missing, |
| -- then we can definitely fall through, and we post the error |
| -- message on the entry call alternative itself. |
| |
| if No (Statements (ECA)) then |
| Last_Stm := ECA; |
| |
| -- Else check statement sequence and else part |
| |
| else |
| Check_Statement_Sequence (Statements (ECA)); |
| Check_Statement_Sequence (Else_Statements (Last_Stm)); |
| return; |
| end if; |
| end; |
| end if; |
| |
| -- If we fall through, issue appropriate message |
| |
| if Mode = 'F' then |
| |
| if not Raise_Exception_Call then |
| Error_Msg_N |
| ("?RETURN statement missing following this statement!", |
| Last_Stm); |
| Error_Msg_N |
| ("\?Program_Error may be raised at run time", |
| Last_Stm); |
| end if; |
| |
| -- Note: we set Err even though we have not issued a warning |
| -- because we still have a case of a missing return. This is |
| -- an extremely marginal case, probably will never be noticed |
| -- but we might as well get it right. |
| |
| Err := True; |
| |
| else |
| Error_Msg_N |
| ("implied return after this statement not allowed (No_Return)", |
| Last_Stm); |
| end if; |
| end Check_Statement_Sequence; |
| |
| -- Start of processing for Check_Returns |
| |
| begin |
| Err := False; |
| Check_Statement_Sequence (Statements (HSS)); |
| |
| if Present (Exception_Handlers (HSS)) then |
| Handler := First_Non_Pragma (Exception_Handlers (HSS)); |
| while Present (Handler) loop |
| Check_Statement_Sequence (Statements (Handler)); |
| Next_Non_Pragma (Handler); |
| end loop; |
| end if; |
| end Check_Returns; |
| |
| ---------------------------- |
| -- Check_Subprogram_Order -- |
| ---------------------------- |
| |
| procedure Check_Subprogram_Order (N : Node_Id) is |
| |
| function Subprogram_Name_Greater (S1, S2 : String) return Boolean; |
| -- This is used to check if S1 > S2 in the sense required by this |
| -- test, for example nameab < namec, but name2 < name10. |
| |
| function Subprogram_Name_Greater (S1, S2 : String) return Boolean is |
| L1, L2 : Positive; |
| N1, N2 : Natural; |
| |
| begin |
| -- Remove trailing numeric parts |
| |
| L1 := S1'Last; |
| while S1 (L1) in '0' .. '9' loop |
| L1 := L1 - 1; |
| end loop; |
| |
| L2 := S2'Last; |
| while S2 (L2) in '0' .. '9' loop |
| L2 := L2 - 1; |
| end loop; |
| |
| -- If non-numeric parts non-equal, that's decisive |
| |
| if S1 (S1'First .. L1) < S2 (S2'First .. L2) then |
| return False; |
| |
| elsif S1 (S1'First .. L1) > S2 (S2'First .. L2) then |
| return True; |
| |
| -- If non-numeric parts equal, compare suffixed numeric parts. Note |
| -- that a missing suffix is treated as numeric zero in this test. |
| |
| else |
| N1 := 0; |
| while L1 < S1'Last loop |
| L1 := L1 + 1; |
| N1 := N1 * 10 + Character'Pos (S1 (L1)) - Character'Pos ('0'); |
| end loop; |
| |
| N2 := 0; |
| while L2 < S2'Last loop |
| L2 := L2 + 1; |
| N2 := N2 * 10 + Character'Pos (S2 (L2)) - Character'Pos ('0'); |
| end loop; |
| |
| return N1 > N2; |
| end if; |
| end Subprogram_Name_Greater; |
| |
| -- Start of processing for Check_Subprogram_Order |
| |
| begin |
| -- Check body in alpha order if this is option |
| |
| if Style_Check |
| and then Style_Check_Subprogram_Order |
| and then Nkind (N) = N_Subprogram_Body |
| and then Comes_From_Source (N) |
| and then In_Extended_Main_Source_Unit (N) |
| then |
| declare |
| LSN : String_Ptr |
| renames Scope_Stack.Table |
| (Scope_Stack.Last).Last_Subprogram_Name; |
| |
| Body_Id : constant Entity_Id := |
| Defining_Entity (Specification (N)); |
| |
| begin |
| Get_Decoded_Name_String (Chars (Body_Id)); |
| |
| if LSN /= null then |
| if Subprogram_Name_Greater |
| (LSN.all, Name_Buffer (1 .. Name_Len)) |
| then |
| Style.Subprogram_Not_In_Alpha_Order (Body_Id); |
| end if; |
| |
| Free (LSN); |
| end if; |
| |
| LSN := new String'(Name_Buffer (1 .. Name_Len)); |
| end; |
| end if; |
| end Check_Subprogram_Order; |
| |
| ------------------------------ |
| -- Check_Subtype_Conformant -- |
| ------------------------------ |
| |
| procedure Check_Subtype_Conformant |
| (New_Id : Entity_Id; |
| Old_Id : Entity_Id; |
| Err_Loc : Node_Id := Empty) |
| is |
| Result : Boolean; |
| |
| begin |
| Check_Conformance |
| (New_Id, Old_Id, Subtype_Conformant, True, Result, Err_Loc); |
| end Check_Subtype_Conformant; |
| |
| --------------------------- |
| -- Check_Type_Conformant -- |
| --------------------------- |
| |
| procedure Check_Type_Conformant |
| (New_Id : Entity_Id; |
| Old_Id : Entity_Id; |
| Err_Loc : Node_Id := Empty) |
| is |
| Result : Boolean; |
| |
| begin |
| Check_Conformance |
| (New_Id, Old_Id, Type_Conformant, True, Result, Err_Loc); |
| end Check_Type_Conformant; |
| |
| ---------------------- |
| -- Conforming_Types -- |
| ---------------------- |
| |
| function Conforming_Types |
| (T1 : Entity_Id; |
| T2 : Entity_Id; |
| Ctype : Conformance_Type; |
| Get_Inst : Boolean := False) return Boolean |
| is |
| Type_1 : Entity_Id := T1; |
| Type_2 : Entity_Id := T2; |
| |
| function Base_Types_Match (T1, T2 : Entity_Id) return Boolean; |
| -- If neither T1 nor T2 are generic actual types, or if they are |
| -- in different scopes (e.g. parent and child instances), then verify |
| -- that the base types are equal. Otherwise T1 and T2 must be |
| -- on the same subtype chain. The whole purpose of this procedure |
| -- is to prevent spurious ambiguities in an instantiation that may |
| -- arise if two distinct generic types are instantiated with the |
| -- same actual. |
| |
| ---------------------- |
| -- Base_Types_Match -- |
| ---------------------- |
| |
| function Base_Types_Match (T1, T2 : Entity_Id) return Boolean is |
| begin |
| if T1 = T2 then |
| return True; |
| |
| elsif Base_Type (T1) = Base_Type (T2) then |
| |
| -- The following is too permissive. A more precise test must |
| -- check that the generic actual is an ancestor subtype of the |
| -- other ???. |
| |
| return not Is_Generic_Actual_Type (T1) |
| or else not Is_Generic_Actual_Type (T2) |
| or else Scope (T1) /= Scope (T2); |
| |
| else |
| return False; |
| end if; |
| end Base_Types_Match; |
| |
| begin |
| -- The context is an instance association for a formal |
| -- access-to-subprogram type; the formal parameter types |
| -- require mapping because they may denote other formal |
| -- parameters of the generic unit. |
| |
| if Get_Inst then |
| Type_1 := Get_Instance_Of (T1); |
| Type_2 := Get_Instance_Of (T2); |
| end if; |
| |
| -- First see if base types match |
| |
| if Base_Types_Match (Type_1, Type_2) then |
| return Ctype <= Mode_Conformant |
| or else Subtypes_Statically_Match (Type_1, Type_2); |
| |
| elsif Is_Incomplete_Or_Private_Type (Type_1) |
| and then Present (Full_View (Type_1)) |
| and then Base_Types_Match (Full_View (Type_1), Type_2) |
| then |
| return Ctype <= Mode_Conformant |
| or else Subtypes_Statically_Match (Full_View (Type_1), Type_2); |
| |
| elsif Ekind (Type_2) = E_Incomplete_Type |
| and then Present (Full_View (Type_2)) |
| and then Base_Types_Match (Type_1, Full_View (Type_2)) |
| then |
| return Ctype <= Mode_Conformant |
| or else Subtypes_Statically_Match (Type_1, Full_View (Type_2)); |
| |
| elsif Is_Private_Type (Type_2) |
| and then In_Instance |
| and then Present (Full_View (Type_2)) |
| and then Base_Types_Match (Type_1, Full_View (Type_2)) |
| then |
| return Ctype <= Mode_Conformant |
| or else Subtypes_Statically_Match (Type_1, Full_View (Type_2)); |
| end if; |
| |
| -- Test anonymous access type case. For this case, static subtype |
| -- matching is required for mode conformance (RM 6.3.1(15)) |
| |
| if Ekind (Type_1) = E_Anonymous_Access_Type |
| and then Ekind (Type_2) = E_Anonymous_Access_Type |
| then |
| declare |
| Desig_1 : Entity_Id; |
| Desig_2 : Entity_Id; |
| |
| begin |
| Desig_1 := Directly_Designated_Type (Type_1); |
| |
| -- An access parameter can designate an incomplete type. |
| |
| if Ekind (Desig_1) = E_Incomplete_Type |
| and then Present (Full_View (Desig_1)) |
| then |
| Desig_1 := Full_View (Desig_1); |
| end if; |
| |
| Desig_2 := Directly_Designated_Type (Type_2); |
| |
| if Ekind (Desig_2) = E_Incomplete_Type |
| and then Present (Full_View (Desig_2)) |
| then |
| Desig_2 := Full_View (Desig_2); |
| end if; |
| |
| -- The context is an instance association for a formal |
| -- access-to-subprogram type; formal access parameter |
| -- designated types require mapping because they may |
| -- denote other formal parameters of the generic unit. |
| |
| if Get_Inst then |
| Desig_1 := Get_Instance_Of (Desig_1); |
| Desig_2 := Get_Instance_Of (Desig_2); |
| end if; |
| |
| -- It is possible for a Class_Wide_Type to be introduced for |
| -- an incomplete type, in which case there is a separate class_ |
| -- wide type for the full view. The types conform if their |
| -- Etypes conform, i.e. one may be the full view of the other. |
| -- This can only happen in the context of an access parameter, |
| -- other uses of an incomplete Class_Wide_Type are illegal. |
| |
| if Is_Class_Wide_Type (Desig_1) |
| and then Is_Class_Wide_Type (Desig_2) |
| then |
| return |
| Conforming_Types |
| (Etype (Base_Type (Desig_1)), |
| Etype (Base_Type (Desig_2)), Ctype); |
| else |
| return Base_Type (Desig_1) = Base_Type (Desig_2) |
| and then (Ctype = Type_Conformant |
| or else |
| Subtypes_Statically_Match (Desig_1, Desig_2)); |
| end if; |
| end; |
| |
| -- Otherwise definitely no match |
| |
| else |
| return False; |
| end if; |
| |
| end Conforming_Types; |
| |
| -------------------------- |
| -- Create_Extra_Formals -- |
| -------------------------- |
| |
| procedure Create_Extra_Formals (E : Entity_Id) is |
| Formal : Entity_Id; |
| Last_Extra : Entity_Id; |
| Formal_Type : Entity_Id; |
| P_Formal : Entity_Id := Empty; |
| |
| function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id; |
| -- Add an extra formal, associated with the current Formal. The |
| -- extra formal is added to the list of extra formals, and also |
| -- returned as the result. These formals are always of mode IN. |
| |
| ---------------------- |
| -- Add_Extra_Formal -- |
| ---------------------- |
| |
| function Add_Extra_Formal (Typ : Entity_Id) return Entity_Id is |
| EF : constant Entity_Id := |
| Make_Defining_Identifier (Sloc (Formal), |
| Chars => New_External_Name (Chars (Formal), 'F')); |
| |
| begin |
| -- We never generate extra formals if expansion is not active |
| -- because we don't need them unless we are generating code. |
| |
| if not Expander_Active then |
| return Empty; |
| end if; |
| |
| -- A little optimization. Never generate an extra formal for |
| -- the _init operand of an initialization procedure, since it |
| -- could never be used. |
| |
| if Chars (Formal) = Name_uInit then |
| return Empty; |
| end if; |
| |
| Set_Ekind (EF, E_In_Parameter); |
| Set_Actual_Subtype (EF, Typ); |
| Set_Etype (EF, Typ); |
| Set_Scope (EF, Scope (Formal)); |
| Set_Mechanism (EF, Default_Mechanism); |
| Set_Formal_Validity (EF); |
| |
| Set_Extra_Formal (Last_Extra, EF); |
| Last_Extra := EF; |
| return EF; |
| end Add_Extra_Formal; |
| |
| -- Start of processing for Create_Extra_Formals |
| |
| begin |
| -- If this is a derived subprogram then the subtypes of the |
| -- parent subprogram's formal parameters will be used to |
| -- to determine the need for extra formals. |
| |
| if Is_Overloadable (E) and then Present (Alias (E)) then |
| P_Formal := First_Formal (Alias (E)); |
| end if; |
| |
| Last_Extra := Empty; |
| Formal := First_Formal (E); |
| while Present (Formal) loop |
| Last_Extra := Formal; |
| Next_Formal (Formal); |
| end loop; |
| |
| -- If Extra_formals where already created, don't do it again |
| -- This situation may arise for subprogram types created as part |
| -- of dispatching calls (see Expand_Dispatch_Call) |
| |
| if Present (Last_Extra) and then |
| Present (Extra_Formal (Last_Extra)) |
| then |
| return; |
| end if; |
| |
| Formal := First_Formal (E); |
| |
| while Present (Formal) loop |
| |
| -- Create extra formal for supporting the attribute 'Constrained. |
| -- The case of a private type view without discriminants also |
| -- requires the extra formal if the underlying type has defaulted |
| -- discriminants. |
| |
| if Ekind (Formal) /= E_In_Parameter then |
| if Present (P_Formal) then |
| Formal_Type := Etype (P_Formal); |
| else |
| Formal_Type := Etype (Formal); |
| end if; |
| |
| if not Has_Discriminants (Formal_Type) |
| and then Ekind (Formal_Type) in Private_Kind |
| and then Present (Underlying_Type (Formal_Type)) |
| then |
| Formal_Type := Underlying_Type (Formal_Type); |
| end if; |
| |
| if Has_Discriminants (Formal_Type) |
| and then |
| ((not Is_Constrained (Formal_Type) |
| and then not Is_Indefinite_Subtype (Formal_Type)) |
| or else Present (Extra_Formal (Formal))) |
| then |
| Set_Extra_Constrained |
| (Formal, Add_Extra_Formal (Standard_Boolean)); |
| end if; |
| end if; |
| |
| -- Create extra formal for supporting accessibility checking |
| |
| -- This is suppressed if we specifically suppress accessibility |
| -- checks at the pacage level for either the subprogram, or the |
| -- package in which it resides. However, we do not suppress it |
| -- simply if the scope has accessibility checks suppressed, since |
| -- this could cause trouble when clients are compiled with a |
| -- different suppression setting. The explicit checks at the |
| -- package level are safe from this point of view. |
| |
| if Ekind (Etype (Formal)) = E_Anonymous_Access_Type |
| and then not |
| (Explicit_Suppress (E, Accessibility_Check) |
| or else |
| Explicit_Suppress (Scope (E), Accessibility_Check)) |
| and then |
| (not Present (P_Formal) |
| or else Present (Extra_Accessibility (P_Formal))) |
| then |
| -- Temporary kludge: for now we avoid creating the extra |
| -- formal for access parameters of protected operations |
| -- because of problem with the case of internal protected |
| -- calls. ??? |
| |
| if Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Definition |
| and then Nkind (Parent (Parent (Parent (E)))) /= N_Protected_Body |
| then |
| Set_Extra_Accessibility |
| (Formal, Add_Extra_Formal (Standard_Natural)); |
| end if; |
| end if; |
| |
| if Present (P_Formal) then |
| Next_Formal (P_Formal); |
| end if; |
| |
| Next_Formal (Formal); |
| end loop; |
| end Create_Extra_Formals; |
| |
| ----------------------------- |
| -- Enter_Overloaded_Entity -- |
| ----------------------------- |
| |
| procedure Enter_Overloaded_Entity (S : Entity_Id) is |
| E : Entity_Id := Current_Entity_In_Scope (S); |
| C_E : Entity_Id := Current_Entity (S); |
| |
| begin |
| if Present (E) then |
| Set_Has_Homonym (E); |
| Set_Has_Homonym (S); |
| end if; |
| |
| Set_Is_Immediately_Visible (S); |
| Set_Scope (S, Current_Scope); |
| |
| -- Chain new entity if front of homonym in current scope, so that |
| -- homonyms are contiguous. |
| |
| if Present (E) |
| and then E /= C_E |
| then |
| while Homonym (C_E) /= E loop |
| C_E := Homonym (C_E); |
| end loop; |
| |
| Set_Homonym (C_E, S); |
| |
| else |
| E := C_E; |
| Set_Current_Entity (S); |
| end if; |
| |
| Set_Homonym (S, E); |
| |
| Append_Entity (S, Current_Scope); |
| Set_Public_Status (S); |
| |
| if Debug_Flag_E then |
| Write_Str ("New overloaded entity chain: "); |
| Write_Name (Chars (S)); |
| E := S; |
| |
| while Present (E) loop |
| Write_Str (" "); Write_Int (Int (E)); |
| E := Homonym (E); |
| end loop; |
| |
| Write_Eol; |
| end if; |
| |
| -- Generate warning for hiding |
| |
| if Warn_On_Hiding |
| and then Comes_From_Source (S) |
| and then In_Extended_Main_Source_Unit (S) |
| then |
| E := S; |
| loop |
| E := Homonym (E); |
| exit when No (E); |
| |
| -- Warn unless genuine overloading |
| |
| if (not Is_Overloadable (E)) |
| or else Subtype_Conformant (E, S) |
| then |
| Error_Msg_Sloc := Sloc (E); |
| Error_Msg_N ("declaration of & hides one#?", S); |
| end if; |
| end loop; |
| end if; |
| end Enter_Overloaded_Entity; |
| |
| ----------------------------- |
| -- Find_Corresponding_Spec -- |
| ----------------------------- |
| |
| function Find_Corresponding_Spec (N : Node_Id) return Entity_Id is |
| Spec : constant Node_Id := Specification (N); |
| Designator : constant Entity_Id := Defining_Entity (Spec); |
| |
| E : Entity_Id; |
| |
| begin |
| E := Current_Entity (Designator); |
| |
| while Present (E) loop |
| |
| -- We are looking for a matching spec. It must have the same scope, |
| -- and the same name, and either be type conformant, or be the case |
| -- of a library procedure spec and its body (which belong to one |
| -- another regardless of whether they are type conformant or not). |
| |
| if Scope (E) = Current_Scope then |
| if Current_Scope = Standard_Standard |
| or else (Ekind (E) = Ekind (Designator) |
| and then Type_Conformant (E, Designator)) |
| then |
| -- Within an instantiation, we know that spec and body are |
| -- subtype conformant, because they were subtype conformant |
| -- in the generic. We choose the subtype-conformant entity |
| -- here as well, to resolve spurious ambiguities in the |
| -- instance that were not present in the generic (i.e. when |
| -- two different types are given the same actual). If we are |
| -- looking for a spec to match a body, full conformance is |
| -- expected. |
| |
| if In_Instance then |
| Set_Convention (Designator, Convention (E)); |
| |
| if Nkind (N) = N_Subprogram_Body |
| and then Present (Homonym (E)) |
| and then not Fully_Conformant (E, Designator) |
| then |
| goto Next_Entity; |
| |
| elsif not Subtype_Conformant (E, Designator) then |
| goto Next_Entity; |
| end if; |
| end if; |
| |
| if not Has_Completion (E) then |
| |
| if Nkind (N) /= N_Subprogram_Body_Stub then |
| Set_Corresponding_Spec (N, E); |
| end if; |
| |
| Set_Has_Completion (E); |
| return E; |
| |
| elsif Nkind (Parent (N)) = N_Subunit then |
| |
| -- If this is the proper body of a subunit, the completion |
| -- flag is set when analyzing the stub. |
| |
| return E; |
| |
| -- If body already exists, this is an error unless the |
| -- previous declaration is the implicit declaration of |
| -- a derived subprogram, or this is a spurious overloading |
| -- in an instance. |
| |
| elsif No (Alias (E)) |
| and then not Is_Intrinsic_Subprogram (E) |
| and then not In_Instance |
| then |
| Error_Msg_Sloc := Sloc (E); |
| if Is_Imported (E) then |
| Error_Msg_NE |
| ("body not allowed for imported subprogram & declared#", |
| N, E); |
| else |
| Error_Msg_NE ("duplicate body for & declared#", N, E); |
| end if; |
| end if; |
| |
| elsif Is_Child_Unit (E) |
| and then |
| Nkind (Unit_Declaration_Node (Designator)) = N_Subprogram_Body |
| and then |
| Nkind (Parent (Unit_Declaration_Node (Designator))) |
| = N_Compilation_Unit |
| then |
| |
| -- Child units cannot be overloaded, so a conformance mismatch |
| -- between body and a previous spec is an error. |
| |
| Error_Msg_N |
| ("body of child unit does not match previous declaration", N); |
| end if; |
| end if; |
| |
| <<Next_Entity>> |
| E := Homonym (E); |
| end loop; |
| |
| -- On exit, we know that no previous declaration of subprogram exists |
| |
| return Empty; |
| end Find_Corresponding_Spec; |
| |
| ---------------------- |
| -- Fully_Conformant -- |
| ---------------------- |
| |
| function Fully_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is |
| Result : Boolean; |
| |
| begin |
| Check_Conformance (New_Id, Old_Id, Fully_Conformant, False, Result); |
| return Result; |
| end Fully_Conformant; |
| |
| ---------------------------------- |
| -- Fully_Conformant_Expressions -- |
| ---------------------------------- |
| |
| function Fully_Conformant_Expressions |
| (Given_E1 : Node_Id; |
| Given_E2 : Node_Id) return Boolean |
| is |
| E1 : constant Node_Id := Original_Node (Given_E1); |
| E2 : constant Node_Id := Original_Node (Given_E2); |
| -- We always test conformance on original nodes, since it is possible |
| -- for analysis and/or expansion to make things look as though they |
| -- conform when they do not, e.g. by converting 1+2 into 3. |
| |
| function FCE (Given_E1, Given_E2 : Node_Id) return Boolean |
| renames Fully_Conformant_Expressions; |
| |
| function FCL (L1, L2 : List_Id) return Boolean; |
| -- Compare elements of two lists for conformance. Elements have to |
| -- be conformant, and actuals inserted as default parameters do not |
| -- match explicit actuals with the same value. |
| |
| function FCO (Op_Node, Call_Node : Node_Id) return Boolean; |
| -- Compare an operator node with a function call. |
| |
| --------- |
| -- FCL -- |
| --------- |
| |
| function FCL (L1, L2 : List_Id) return Boolean is |
| N1, N2 : Node_Id; |
| |
| begin |
| if L1 = No_List then |
| N1 := Empty; |
| else |
| N1 := First (L1); |
| end if; |
| |
| if L2 = No_List then |
| N2 := Empty; |
| else |
| N2 := First (L2); |
| end if; |
| |
| -- Compare two lists, skipping rewrite insertions (we want to |
| -- compare the original trees, not the expanded versions!) |
| |
| loop |
| if Is_Rewrite_Insertion (N1) then |
| Next (N1); |
| elsif Is_Rewrite_Insertion (N2) then |
| Next (N2); |
| elsif No (N1) then |
| return No (N2); |
| elsif No (N2) then |
| return False; |
| elsif not FCE (N1, N2) then |
| return False; |
| else |
| Next (N1); |
| Next (N2); |
| end if; |
| end loop; |
| end FCL; |
| |
| --------- |
| -- FCO -- |
| --------- |
| |
| function FCO (Op_Node, Call_Node : Node_Id) return Boolean is |
| Actuals : constant List_Id := Parameter_Associations (Call_Node); |
| Act : Node_Id; |
| |
| begin |
| if No (Actuals) |
| or else Entity (Op_Node) /= Entity (Name (Call_Node)) |
| then |
| return False; |
| |
| else |
| Act := First (Actuals); |
| |
| if Nkind (Op_Node) in N_Binary_Op then |
| |
| if not FCE (Left_Opnd (Op_Node), Act) then |
| return False; |
| end if; |
| |
| Next (Act); |
| end if; |
| |
| return Present (Act) |
| and then FCE (Right_Opnd (Op_Node), Act) |
| and then No (Next (Act)); |
| end if; |
| end FCO; |
| |
| -- Start of processing for Fully_Conformant_Expressions |
| |
| begin |
| -- Non-conformant if paren count does not match. Note: if some idiot |
| -- complains that we don't do this right for more than 3 levels of |
| -- parentheses, they will be treated with the respect they deserve :-) |
| |
| if Paren_Count (E1) /= Paren_Count (E2) then |
| return False; |
| |
| -- If same entities are referenced, then they are conformant |
| -- even if they have different forms (RM 8.3.1(19-20)). |
| |
| elsif Is_Entity_Name (E1) and then Is_Entity_Name (E2) then |
| if Present (Entity (E1)) then |
| return Entity (E1) = Entity (E2) |
| or else (Chars (Entity (E1)) = Chars (Entity (E2)) |
| and then Ekind (Entity (E1)) = E_Discriminant |
| and then Ekind (Entity (E2)) = E_In_Parameter); |
| |
| elsif Nkind (E1) = N_Expanded_Name |
| and then Nkind (E2) = N_Expanded_Name |
| and then Nkind (Selector_Name (E1)) = N_Character_Literal |
| and then Nkind (Selector_Name (E2)) = N_Character_Literal |
| then |
| return Chars (Selector_Name (E1)) = Chars (Selector_Name (E2)); |
| |
| else |
| -- Identifiers in component associations don't always have |
| -- entities, but their names must conform. |
| |
| return Nkind (E1) = N_Identifier |
| and then Nkind (E2) = N_Identifier |
| and then Chars (E1) = Chars (E2); |
| end if; |
| |
| elsif Nkind (E1) = N_Character_Literal |
| and then Nkind (E2) = N_Expanded_Name |
| then |
| return Nkind (Selector_Name (E2)) = N_Character_Literal |
| and then Chars (E1) = Chars (Selector_Name (E2)); |
| |
| elsif Nkind (E2) = N_Character_Literal |
| and then Nkind (E1) = N_Expanded_Name |
| then |
| return Nkind (Selector_Name (E1)) = N_Character_Literal |
| and then Chars (E2) = Chars (Selector_Name (E1)); |
| |
| elsif Nkind (E1) in N_Op |
| and then Nkind (E2) = N_Function_Call |
| then |
| return FCO (E1, E2); |
| |
| elsif Nkind (E2) in N_Op |
| and then Nkind (E1) = N_Function_Call |
| then |
| return FCO (E2, E1); |
| |
| -- Otherwise we must have the same syntactic entity |
| |
| elsif Nkind (E1) /= Nkind (E2) then |
| return False; |
| |
| -- At this point, we specialize by node type |
| |
| else |
| case Nkind (E1) is |
| |
| when N_Aggregate => |
| return |
| FCL (Expressions (E1), Expressions (E2)) |
| and then FCL (Component_Associations (E1), |
| Component_Associations (E2)); |
| |
| when N_Allocator => |
| if Nkind (Expression (E1)) = N_Qualified_Expression |
| or else |
| Nkind (Expression (E2)) = N_Qualified_Expression |
| then |
| return FCE (Expression (E1), Expression (E2)); |
| |
| -- Check that the subtype marks and any constraints |
| -- are conformant |
| |
| else |
| declare |
| Indic1 : constant Node_Id := Expression (E1); |
| Indic2 : constant Node_Id := Expression (E2); |
| Elt1 : Node_Id; |
| Elt2 : Node_Id; |
| |
| begin |
| if Nkind (Indic1) /= N_Subtype_Indication then |
| return |
| Nkind (Indic2) /= N_Subtype_Indication |
| and then Entity (Indic1) = Entity (Indic2); |
| |
| elsif Nkind (Indic2) /= N_Subtype_Indication then |
| return |
| Nkind (Indic1) /= N_Subtype_Indication |
| and then Entity (Indic1) = Entity (Indic2); |
| |
| else |
| if Entity (Subtype_Mark (Indic1)) /= |
| Entity (Subtype_Mark (Indic2)) |
| then |
| return False; |
| end if; |
| |
| Elt1 := First (Constraints (Constraint (Indic1))); |
| Elt2 := First (Constraints (Constraint (Indic2))); |
| |
| while Present (Elt1) and then Present (Elt2) loop |
| if not FCE (Elt1, Elt2) then |
| return False; |
| end if; |
| |
| Next (Elt1); |
| Next (Elt2); |
| end loop; |
| |
| return True; |
| end if; |
| end; |
| end if; |
| |
| when N_Attribute_Reference => |
| return |
| Attribute_Name (E1) = Attribute_Name (E2) |
| and then FCL (Expressions (E1), Expressions (E2)); |
| |
| when N_Binary_Op => |
| return |
| Entity (E1) = Entity (E2) |
| and then FCE (Left_Opnd (E1), Left_Opnd (E2)) |
| and then FCE (Right_Opnd (E1), Right_Opnd (E2)); |
| |
| when N_And_Then | N_Or_Else | N_In | N_Not_In => |
| return |
| FCE (Left_Opnd (E1), Left_Opnd (E2)) |
| and then |
| FCE (Right_Opnd (E1), Right_Opnd (E2)); |
| |
| when N_Character_Literal => |
| return |
| Char_Literal_Value (E1) = Char_Literal_Value (E2); |
| |
| when N_Component_Association => |
| return |
| FCL (Choices (E1), Choices (E2)) |
| and then FCE (Expression (E1), Expression (E2)); |
| |
| when N_Conditional_Expression => |
| return |
| FCL (Expressions (E1), Expressions (E2)); |
| |
| when N_Explicit_Dereference => |
| return |
| FCE (Prefix (E1), Prefix (E2)); |
| |
| when N_Extension_Aggregate => |
| return |
| FCL (Expressions (E1), Expressions (E2)) |
| and then Null_Record_Present (E1) = |
| Null_Record_Present (E2) |
| and then FCL (Component_Associations (E1), |
| Component_Associations (E2)); |
| |
| when N_Function_Call => |
| return |
| FCE (Name (E1), Name (E2)) |
| and then FCL (Parameter_Associations (E1), |
| Parameter_Associations (E2)); |
| |
| when N_Indexed_Component => |
| return |
| FCE (Prefix (E1), Prefix (E2)) |
| and then FCL (Expressions (E1), Expressions (E2)); |
| |
| when N_Integer_Literal => |
| return (Intval (E1) = Intval (E2)); |
| |
| when N_Null => |
| return True; |
| |
| when N_Operator_Symbol => |
| return |
| Chars (E1) = Chars (E2); |
| |
| when N_Others_Choice => |
| return True; |
| |
| when N_Parameter_Association => |
| return |
| Chars (Selector_Name (E1)) = Chars (Selector_Name (E2)) |
| and then FCE (Explicit_Actual_Parameter (E1), |
| Explicit_Actual_Parameter (E2)); |
| |
| when N_Qualified_Expression => |
| return |
| FCE (Subtype_Mark (E1), Subtype_Mark (E2)) |
| and then FCE (Expression (E1), Expression (E2)); |
| |
| when N_Range => |
| return |
| FCE (Low_Bound (E1), Low_Bound (E2)) |
| and then FCE (High_Bound (E1), High_Bound (E2)); |
| |
| when N_Real_Literal => |
| return (Realval (E1) = Realval (E2)); |
| |
| when N_Selected_Component => |
| return |
| FCE (Prefix (E1), Prefix (E2)) |
| and then FCE (Selector_Name (E1), Selector_Name (E2)); |
| |
| when N_Slice => |
| return |
| FCE (Prefix (E1), Prefix (E2)) |
| and then FCE (Discrete_Range (E1), Discrete_Range (E2)); |
| |
| when N_String_Literal => |
| declare |
| S1 : constant String_Id := Strval (E1); |
| S2 : constant String_Id := Strval (E2); |
| L1 : constant Nat := String_Length (S1); |
| L2 : constant Nat := String_Length (S2); |
| |
| begin |
| if L1 /= L2 then |
| return False; |
| |
| else |
| for J in 1 .. L1 loop |
| if Get_String_Char (S1, J) /= |
| Get_String_Char (S2, J) |
| then |
| return False; |
| end if; |
| end loop; |
| |
| return True; |
| end if; |
| end; |
| |
| when N_Type_Conversion => |
| return |
| FCE (Subtype_Mark (E1), Subtype_Mark (E2)) |
| and then FCE (Expression (E1), Expression (E2)); |
| |
| when N_Unary_Op => |
| return |
| Entity (E1) = Entity (E2) |
| and then FCE (Right_Opnd (E1), Right_Opnd (E2)); |
| |
| when N_Unchecked_Type_Conversion => |
| return |
| FCE (Subtype_Mark (E1), Subtype_Mark (E2)) |
| and then FCE (Expression (E1), Expression (E2)); |
| |
| -- All other node types cannot appear in this context. Strictly |
| -- we should raise a fatal internal error. Instead we just ignore |
| -- the nodes. This means that if anyone makes a mistake in the |
| -- expander and mucks an expression tree irretrievably, the |
| -- result will be a failure to detect a (probably very obscure) |
| -- case of non-conformance, which is better than bombing on some |
| -- case where two expressions do in fact conform. |
| |
| when others => |
| return True; |
| |
| end case; |
| end if; |
| end Fully_Conformant_Expressions; |
| |
| ---------------------------------------- |
| -- Fully_Conformant_Discrete_Subtypes -- |
| ---------------------------------------- |
| |
| function Fully_Conformant_Discrete_Subtypes |
| (Given_S1 : Node_Id; |
| Given_S2 : Node_Id) return Boolean |
| is |
| S1 : constant Node_Id := Original_Node (Given_S1); |
| S2 : constant Node_Id := Original_Node (Given_S2); |
| |
| function Conforming_Bounds (B1, B2 : Node_Id) return Boolean; |
| -- Special-case for a bound given by a discriminant, which in the |
| -- body is replaced with the discriminal of the enclosing type. |
| |
| function Conforming_Ranges (R1, R2 : Node_Id) return Boolean; |
| -- Check both bounds. |
| |
| function Conforming_Bounds (B1, B2 : Node_Id) return Boolean is |
| begin |
| if Is_Entity_Name (B1) |
| and then Is_Entity_Name (B2) |
| and then Ekind (Entity (B1)) = E_Discriminant |
| then |
| return Chars (B1) = Chars (B2); |
| |
| else |
| return Fully_Conformant_Expressions (B1, B2); |
| end if; |
| end Conforming_Bounds; |
| |
| function Conforming_Ranges (R1, R2 : Node_Id) return Boolean is |
| begin |
| return |
| Conforming_Bounds (Low_Bound (R1), Low_Bound (R2)) |
| and then |
| Conforming_Bounds (High_Bound (R1), High_Bound (R2)); |
| end Conforming_Ranges; |
| |
| -- Start of processing for Fully_Conformant_Discrete_Subtypes |
| |
| begin |
| if Nkind (S1) /= Nkind (S2) then |
| return False; |
| |
| elsif Is_Entity_Name (S1) then |
| return Entity (S1) = Entity (S2); |
| |
| elsif Nkind (S1) = N_Range then |
| return Conforming_Ranges (S1, S2); |
| |
| elsif Nkind (S1) = N_Subtype_Indication then |
| return |
| Entity (Subtype_Mark (S1)) = Entity (Subtype_Mark (S2)) |
| and then |
| Conforming_Ranges |
| (Range_Expression (Constraint (S1)), |
| Range_Expression (Constraint (S2))); |
| else |
| return True; |
| end if; |
| end Fully_Conformant_Discrete_Subtypes; |
| |
| -------------------- |
| -- Install_Entity -- |
| -------------------- |
| |
| procedure Install_Entity (E : Entity_Id) is |
| Prev : constant Entity_Id := Current_Entity (E); |
| |
| begin |
| Set_Is_Immediately_Visible (E); |
| Set_Current_Entity (E); |
| Set_Homonym (E, Prev); |
| end Install_Entity; |
| |
| --------------------- |
| -- Install_Formals -- |
| --------------------- |
| |
| procedure Install_Formals (Id : Entity_Id) is |
| F : Entity_Id; |
| |
| begin |
| F := First_Formal (Id); |
| |
| while Present (F) loop |
| Install_Entity (F); |
| Next_Formal (F); |
| end loop; |
| end Install_Formals; |
| |
| --------------------------------- |
| -- Is_Non_Overriding_Operation -- |
| --------------------------------- |
| |
| function Is_Non_Overriding_Operation |
| (Prev_E : Entity_Id; |
| New_E : Entity_Id) return Boolean |
| is |
| Formal : Entity_Id; |
| F_Typ : Entity_Id; |
| G_Typ : Entity_Id := Empty; |
| |
| function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id; |
| -- If F_Type is a derived type associated with a generic actual |
| -- subtype, then return its Generic_Parent_Type attribute, else |
| -- return Empty. |
| |
| function Types_Correspond |
| (P_Type : Entity_Id; |
| N_Type : Entity_Id) return Boolean; |
| -- Returns true if and only if the types (or designated types |
| -- in the case of anonymous access types) are the same or N_Type |
| -- is derived directly or indirectly from P_Type. |
| |
| ----------------------------- |
| -- Get_Generic_Parent_Type -- |
| ----------------------------- |
| |
| function Get_Generic_Parent_Type (F_Typ : Entity_Id) return Entity_Id is |
| G_Typ : Entity_Id; |
| Indic : Node_Id; |
| |
| begin |
| if Is_Derived_Type (F_Typ) |
| and then Nkind (Parent (F_Typ)) = N_Full_Type_Declaration |
| then |
| -- The tree must be traversed to determine the parent |
| -- subtype in the generic unit, which unfortunately isn't |
| -- always available via semantic attributes. ??? |
| -- (Note: The use of Original_Node is needed for cases |
| -- where a full derived type has been rewritten.) |
| |
| Indic := Subtype_Indication |
| (Type_Definition (Original_Node (Parent (F_Typ)))); |
| |
| if Nkind (Indic) = N_Subtype_Indication then |
| G_Typ := Entity (Subtype_Mark (Indic)); |
| else |
| G_Typ := Entity (Indic); |
| end if; |
| |
| if Nkind (Parent (G_Typ)) = N_Subtype_Declaration |
| and then Present (Generic_Parent_Type (Parent (G_Typ))) |
| then |
| return Generic_Parent_Type (Parent (G_Typ)); |
| end if; |
| end if; |
| |
| return Empty; |
| end Get_Generic_Parent_Type; |
| |
| ---------------------- |
| -- Types_Correspond -- |
| ---------------------- |
| |
| function Types_Correspond |
| (P_Type : Entity_Id; |
| N_Type : Entity_Id) return Boolean |
| is |
| Prev_Type : Entity_Id := Base_Type (P_Type); |
| New_Type : Entity_Id := Base_Type (N_Type); |
| |
| begin |
| if Ekind (Prev_Type) = E_Anonymous_Access_Type then |
| Prev_Type := Designated_Type (Prev_Type); |
| end if; |
| |
| if Ekind (New_Type) = E_Anonymous_Access_Type then |
| New_Type := Designated_Type (New_Type); |
| end if; |
| |
| if Prev_Type = New_Type then |
| return True; |
| |
| elsif not Is_Class_Wide_Type (New_Type) then |
| while Etype (New_Type) /= New_Type loop |
| New_Type := Etype (New_Type); |
| if New_Type = Prev_Type then |
| return True; |
| end if; |
| end loop; |
| end if; |
| return False; |
| end Types_Correspond; |
| |
| -- Start of processing for Is_Non_Overriding_Operation |
| |
| begin |
| -- In the case where both operations are implicit derived |
| -- subprograms then neither overrides the other. This can |
| -- only occur in certain obscure cases (e.g., derivation |
| -- from homographs created in a generic instantiation). |
| |
| if Present (Alias (Prev_E)) and then Present (Alias (New_E)) then |
| return True; |
| |
| elsif Ekind (Current_Scope) = E_Package |
| and then Is_Generic_Instance (Current_Scope) |
| and then In_Private_Part (Current_Scope) |
| and then Comes_From_Source (New_E) |
| then |
| -- We examine the formals and result subtype of the inherited |
| -- operation, to determine whether their type is derived from |
| -- (the instance of) a generic type. |
| |
| Formal := First_Formal (Prev_E); |
| |
| while Present (Formal) loop |
| F_Typ := Base_Type (Etype (Formal)); |
| |
| if Ekind (F_Typ) = E_Anonymous_Access_Type then |
| F_Typ := Designated_Type (F_Typ); |
| end if; |
| |
| G_Typ := Get_Generic_Parent_Type (F_Typ); |
| |
| Next_Formal (Formal); |
| end loop; |
| |
| if not Present (G_Typ) and then Ekind (Prev_E) = E_Function then |
| G_Typ := Get_Generic_Parent_Type (Base_Type (Etype (Prev_E))); |
| end if; |
| |
| if No (G_Typ) then |
| return False; |
| end if; |
| |
| -- If the generic type is a private type, then the original |
| -- operation was not overriding in the generic, because there was |
| -- no primitive operation to override. |
| |
| if Nkind (Parent (G_Typ)) = N_Formal_Type_Declaration |
| and then Nkind (Formal_Type_Definition (Parent (G_Typ))) = |
| N_Formal_Private_Type_Definition |
| then |
| return True; |
| |
| -- The generic parent type is the ancestor of a formal derived |
| -- type declaration. We need to check whether it has a primitive |
| -- operation that should be overridden by New_E in the generic. |
| |
| else |
| declare |
| P_Formal : Entity_Id; |
| N_Formal : Entity_Id; |
| P_Typ : Entity_Id; |
| N_Typ : Entity_Id; |
| P_Prim : Entity_Id; |
| Prim_Elt : Elmt_Id := First_Elmt (Primitive_Operations (G_Typ)); |
| |
| begin |
| while Present (Prim_Elt) loop |
| P_Prim := Node (Prim_Elt); |
| |
| if Chars (P_Prim) = Chars (New_E) |
| and then Ekind (P_Prim) = Ekind (New_E) |
| then |
| P_Formal := First_Formal (P_Prim); |
| N_Formal := First_Formal (New_E); |
| while Present (P_Formal) and then Present (N_Formal) loop |
| P_Typ := Etype (P_Formal); |
| N_Typ := Etype (N_Formal); |
| |
| if not Types_Correspond (P_Typ, N_Typ) then |
| exit; |
| end if; |
| |
| Next_Entity (P_Formal); |
| Next_Entity (N_Formal); |
| end loop; |
| |
| -- Found a matching primitive operation belonging to |
| -- the formal ancestor type, so the new subprogram |
| -- is overriding. |
| |
| if not Present (P_Formal) |
| and then not Present (N_Formal) |
| and then (Ekind (New_E) /= E_Function |
| or else |
| Types_Correspond |
| (Etype (P_Prim), Etype (New_E))) |
| then |
| return False; |
| end if; |
| end if; |
| |
| Next_Elmt (Prim_Elt); |
| end loop; |
| |
| -- If no match found, then the new subprogram does |
| -- not override in the generic (nor in the instance). |
| |
| return True; |
| end; |
| end if; |
| else |
| return False; |
| end if; |
| end Is_Non_Overriding_Operation; |
| |
| ------------------------------ |
| -- Make_Inequality_Operator -- |
| ------------------------------ |
| |
| -- S is the defining identifier of an equality operator. We build a |
| -- subprogram declaration with the right signature. This operation is |
| -- intrinsic, because it is always expanded as the negation of the |
| -- call to the equality function. |
| |
| procedure Make_Inequality_Operator (S : Entity_Id) is |
| Loc : constant Source_Ptr := Sloc (S); |
| Decl : Node_Id; |
| Formals : List_Id; |
| Op_Name : Entity_Id; |
| |
| A : Entity_Id; |
| B : Entity_Id; |
| |
| begin |
| -- Check that equality was properly defined. |
| |
| if No (Next_Formal (First_Formal (S))) then |
| return; |
| end if; |
| |
| A := Make_Defining_Identifier (Loc, Chars (First_Formal (S))); |
| B := Make_Defining_Identifier (Loc, |
| Chars (Next_Formal (First_Formal (S)))); |
| |
| Op_Name := Make_Defining_Operator_Symbol (Loc, Name_Op_Ne); |
| |
| Formals := New_List ( |
| Make_Parameter_Specification (Loc, |
| Defining_Identifier => A, |
| Parameter_Type => |
| New_Reference_To (Etype (First_Formal (S)), Loc)), |
| |
| Make_Parameter_Specification (Loc, |
| Defining_Identifier => B, |
| Parameter_Type => |
| New_Reference_To (Etype (Next_Formal (First_Formal (S))), Loc))); |
| |
| Decl := |
| Make_Subprogram_Declaration (Loc, |
| Specification => |
| Make_Function_Specification (Loc, |
| Defining_Unit_Name => Op_Name, |
| Parameter_Specifications => Formals, |
| Subtype_Mark => New_Reference_To (Standard_Boolean, Loc))); |
| |
| -- Insert inequality right after equality if it is explicit or after |
| -- the derived type when implicit. These entities are created only |
| -- for visibility purposes, and eventually replaced in the course of |
| -- expansion, so they do not need to be attached to the tree and seen |
| -- by the back-end. Keeping them internal also avoids spurious freezing |
| -- problems. The parent field is set simply to make analysis safe. |
| |
| if No (Alias (S)) then |
| Set_Parent (Decl, Parent (Unit_Declaration_Node (S))); |
| else |
| Set_Parent (Decl, Parent (Parent (Etype (First_Formal (S))))); |
| end if; |
| |
| Mark_Rewrite_Insertion (Decl); |
| Set_Is_Intrinsic_Subprogram (Op_Name); |
| Analyze (Decl); |
| Set_Has_Completion (Op_Name); |
| Set_Corresponding_Equality (Op_Name, S); |
| Set_Is_Abstract (Op_Name, Is_Abstract (S)); |
| |
| end Make_Inequality_Operator; |
| |
| ---------------------- |
| -- May_Need_Actuals -- |
| ---------------------- |
| |
| procedure May_Need_Actuals (Fun : Entity_Id) is |
| F : Entity_Id; |
| B : Boolean; |
| |
| begin |
| F := First_Formal (Fun); |
| B := True; |
| |
| while Present (F) loop |
| if No (Default_Value (F)) then |
| B := False; |
| exit; |
| end if; |
| |
| Next_Formal (F); |
| end loop; |
| |
| Set_Needs_No_Actuals (Fun, B); |
| end May_Need_Actuals; |
| |
| --------------------- |
| -- Mode_Conformant -- |
| --------------------- |
| |
| function Mode_Conformant (New_Id, Old_Id : Entity_Id) return Boolean is |
| Result : Boolean; |
| |
| begin |
| Check_Conformance (New_Id, Old_Id, Mode_Conformant, False, Result); |
| return Result; |
| end Mode_Conformant; |
| |
| --------------------------- |
| -- New_Overloaded_Entity -- |
| --------------------------- |
| |
| procedure New_Overloaded_Entity |
| (S : Entity_Id; |
| Derived_Type : Entity_Id := Empty) |
| is |
| E : Entity_Id; |
| -- Entity that S overrides |
| |
| Prev_Vis : Entity_Id := Empty; |
| -- Needs comment ??? |
| |
| function Is_Private_Declaration (E : Entity_Id) return Boolean; |
| -- Check that E is declared in the private part of the current package, |
| -- or in the package body, where it may hide a previous declaration. |
| -- We can't use In_Private_Part by itself because this flag is also |
| -- set when freezing entities, so we must examine the place of the |
| -- declaration in the tree, and recognize wrapper packages as well. |
| |
| procedure Maybe_Primitive_Operation (Overriding : Boolean := False); |
| -- If the subprogram being analyzed is a primitive operation of |
| -- the type of one of its formals, set the corresponding flag. |
| |
| ---------------------------- |
| -- Is_Private_Declaration -- |
| ---------------------------- |
| |
| function Is_Private_Declaration (E : Entity_Id) return Boolean is |
| Priv_Decls : List_Id; |
| Decl : constant Node_Id := Unit_Declaration_Node (E); |
| |
| begin |
| if Is_Package (Current_Scope) |
| and then In_Private_Part (Current_Scope) |
| then |
| Priv_Decls := |
| Private_Declarations ( |
| Specification (Unit_Declaration_Node (Current_Scope))); |
| |
| return In_Package_Body (Current_Scope) |
| or else List_Containing (Decl) = Priv_Decls |
| or else (Nkind (Parent (Decl)) = N_Package_Specification |
| and then not Is_Compilation_Unit ( |
| Defining_Entity (Parent (Decl))) |
| and then List_Containing (Parent (Parent (Decl))) |
| = Priv_Decls); |
| else |
| return False; |
| end if; |
| end Is_Private_Declaration; |
| |
| ------------------------------- |
| -- Maybe_Primitive_Operation -- |
| ------------------------------- |
| |
| procedure Maybe_Primitive_Operation (Overriding : Boolean := False) is |
| Formal : Entity_Id; |
| F_Typ : Entity_Id; |
| B_Typ : Entity_Id; |
| |
| function Visible_Part_Type (T : Entity_Id) return Boolean; |
| -- Returns true if T is declared in the visible part of |
| -- the current package scope; otherwise returns false. |
| -- Assumes that T is declared in a package. |
| |
| procedure Check_Private_Overriding (T : Entity_Id); |
| -- Checks that if a primitive abstract subprogram of a visible |
| -- abstract type is declared in a private part, then it must |
| -- override an abstract subprogram declared in the visible part. |
| -- Also checks that if a primitive function with a controlling |
| -- result is declared in a private part, then it must override |
| -- a function declared in the visible part. |
| |
| ------------------------------ |
| -- Check_Private_Overriding -- |
| ------------------------------ |
| |
| procedure Check_Private_Overriding (T : Entity_Id) is |
| begin |
| if Ekind (Current_Scope) = E_Package |
| and then In_Private_Part (Current_Scope) |
| and then Visible_Part_Type (T) |
| and then not In_Instance |
| then |
| if Is_Abstract (T) |
| and then Is_Abstract (S) |
| and then (not Overriding or else not Is_Abstract (E)) |
| then |
| Error_Msg_N ("abstract subprograms must be visible " |
| & "('R'M 3.9.3(10))!", S); |
| |
| elsif Ekind (S) = E_Function |
| and then Is_Tagged_Type (T) |
| and then T = Base_Type (Etype (S)) |
| and then not Overriding |
| then |
| Error_Msg_N |
| ("private function with tagged result must" |
| & " override visible-part function", S); |
| Error_Msg_N |
|
|