| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S E M _ C H 3 -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 1992-2014, 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 3, 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 COPYING3. If not, go to -- |
| -- http://www.gnu.org/licenses for a complete copy of the license. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with Nlists; use Nlists; |
| with Types; use Types; |
| |
| package Sem_Ch3 is |
| procedure Analyze_Component_Declaration (N : Node_Id); |
| procedure Analyze_Full_Type_Declaration (N : Node_Id); |
| procedure Analyze_Incomplete_Type_Decl (N : Node_Id); |
| procedure Analyze_Itype_Reference (N : Node_Id); |
| procedure Analyze_Number_Declaration (N : Node_Id); |
| procedure Analyze_Object_Declaration (N : Node_Id); |
| procedure Analyze_Others_Choice (N : Node_Id); |
| procedure Analyze_Private_Extension_Declaration (N : Node_Id); |
| procedure Analyze_Subtype_Indication (N : Node_Id); |
| procedure Analyze_Variant_Part (N : Node_Id); |
| |
| procedure Analyze_Subtype_Declaration |
| (N : Node_Id; |
| Skip : Boolean := False); |
| -- Called to analyze a subtype declaration. The parameter Skip is used for |
| -- Ada 2005 (AI-412). We set to True in order to avoid reentering the |
| -- defining identifier of N when analyzing a rewritten incomplete subtype |
| -- declaration. |
| |
| function Access_Definition |
| (Related_Nod : Node_Id; |
| N : Node_Id) return Entity_Id; |
| -- An access definition defines a general access type for a formal |
| -- parameter. The procedure is called when processing formals, when the |
| -- current scope is the subprogram. The Implicit type is attached to the |
| -- Related_Nod put into the enclosing scope, so that the only entities |
| -- defined in the spec are the formals themselves. |
| |
| procedure Access_Subprogram_Declaration |
| (T_Name : Entity_Id; |
| T_Def : Node_Id); |
| -- The subprogram specification yields the signature of an implicit |
| -- type, whose Ekind is Access_Subprogram_Type. This implicit type is the |
| -- designated type of the declared access type. In subprogram calls, the |
| -- signature of the implicit type works like the profile of a regular |
| -- subprogram. |
| |
| procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id); |
| -- Add to the list of primitives of Tagged_Type the internal entities |
| -- associated with covered interface primitives. These entities link the |
| -- interface primitives with the tagged type primitives that cover them. |
| |
| procedure Analyze_Declarations (L : List_Id); |
| -- Called to analyze a list of declarations (in what context ???). Also |
| -- performs necessary freezing actions (more description needed ???) |
| |
| procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id); |
| -- Analyze an interface declaration or a formal interface declaration |
| |
| procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id); |
| -- Process an array type declaration. If the array is constrained, we |
| -- create an implicit parent array type, with the same index types and |
| -- component type. |
| |
| procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id); |
| -- Process an access type declaration |
| |
| procedure Build_Itype_Reference (Ityp : Entity_Id; Nod : Node_Id); |
| -- Create a reference to an internal type, for use by Gigi. The back-end |
| -- elaborates itypes on demand, i.e. when their first use is seen. This can |
| -- lead to scope anomalies if the first use is within a scope that is |
| -- nested within the scope that contains the point of definition of the |
| -- itype. The Itype_Reference node forces the elaboration of the itype |
| -- in the proper scope. The node is inserted after Nod, which is the |
| -- enclosing declaration that generated Ityp. |
| -- |
| -- A related mechanism is used during expansion, for itypes created in |
| -- branches of conditionals. See Ensure_Defined in exp_util. Could both |
| -- mechanisms be merged ??? |
| |
| procedure Check_Abstract_Overriding (T : Entity_Id); |
| -- Check that all abstract subprograms inherited from T's parent type have |
| -- been overridden as required, and that nonabstract subprograms have not |
| -- been incorrectly overridden with an abstract subprogram. |
| |
| procedure Check_Aliased_Component_Types (T : Entity_Id); |
| -- Given an array type or record type T, check that if the type is |
| -- nonlimited, then the nominal subtype of any components of T that |
| -- have discriminants must be constrained. |
| |
| procedure Check_Completion (Body_Id : Node_Id := Empty); |
| -- At the end of a declarative part, verify that all entities that require |
| -- completion have received one. If Body_Id is absent, the error indicating |
| -- a missing completion is placed on the declaration that needs completion. |
| -- If Body_Id is present, it is the defining identifier of a package body, |
| -- and errors are posted on that node, rather than on the declarations that |
| -- require completion in the package declaration. |
| |
| procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id); |
| -- Check that components of imported CPP type T do not have default |
| -- expressions because the constructor (if any) is on the C++ side. |
| |
| procedure Derive_Subprogram |
| (New_Subp : in out Entity_Id; |
| Parent_Subp : Entity_Id; |
| Derived_Type : Entity_Id; |
| Parent_Type : Entity_Id; |
| Actual_Subp : Entity_Id := Empty); |
| -- Derive the subprogram Parent_Subp from Parent_Type, and replace the |
| -- subsidiary subtypes with the derived type to build the specification of |
| -- the inherited subprogram (returned in New_Subp). For tagged types, the |
| -- derived subprogram is aliased to that of the actual (in the case where |
| -- Actual_Subp is nonempty) rather than to the corresponding subprogram of |
| -- the parent type. |
| |
| procedure Derive_Subprograms |
| (Parent_Type : Entity_Id; |
| Derived_Type : Entity_Id; |
| Generic_Actual : Entity_Id := Empty); |
| -- To complete type derivation, collect/retrieve the primitive operations |
| -- of the parent type, and replace the subsidiary subtypes with the derived |
| -- type, to build the specs of the inherited ops. For generic actuals, the |
| -- mapping of the primitive operations to those of the parent type is also |
| -- done by rederiving the operations within the instance. For tagged types, |
| -- the derived subprograms are aliased to those of the actual, not those of |
| -- the ancestor. |
| -- |
| -- Note: one might expect this to be private to the package body, but there |
| -- is one rather unusual usage in package Exp_Dist. |
| |
| function Find_Hidden_Interface |
| (Src : Elist_Id; |
| Dest : Elist_Id) return Entity_Id; |
| -- Ada 2005: Determine whether the interfaces in list Src are all present |
| -- in the list Dest. Return the first differing interface, or Empty |
| -- otherwise. |
| |
| function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id; |
| -- Given a subtype indication S (which is really an N_Subtype_Indication |
| -- node or a plain N_Identifier), find the type of the subtype mark. |
| |
| function Find_Type_Name (N : Node_Id) return Entity_Id; |
| -- Enter the identifier in a type definition, or find the entity already |
| -- declared, in the case of the full declaration of an incomplete or |
| -- private type. If the previous declaration is tagged then the class-wide |
| -- entity is propagated to the identifier to prevent multiple incompatible |
| -- class-wide types that may be created for self-referential anonymous |
| -- access components. |
| |
| function Get_Discriminant_Value |
| (Discriminant : Entity_Id; |
| Typ_For_Constraint : Entity_Id; |
| Constraint : Elist_Id) return Node_Id; |
| -- ??? MORE DOCUMENTATION |
| -- Given a discriminant somewhere in the Typ_For_Constraint tree and a |
| -- Constraint, return the value of that discriminant. |
| |
| function Is_Null_Extension (T : Entity_Id) return Boolean; |
| -- Returns True if the tagged type T has an N_Full_Type_Declaration that |
| -- is a null extension, meaning that it has an extension part without any |
| -- components and does not have a known discriminant part. |
| |
| function Is_Visible_Component |
| (C : Entity_Id; |
| N : Node_Id := Empty) return Boolean; |
| -- Determines if a record component C is visible in the present context. |
| -- Note that even though component C could appear in the entity chain of a |
| -- record type, C may not be visible in the current context. For instance, |
| -- C may be a component inherited in the full view of a private extension |
| -- which is not visible in the current context. |
| -- |
| -- If present, N is the selected component of which C is the selector. If |
| -- the prefix of N is a type conversion inserted for a discriminant check, |
| -- C is automatically visible. |
| |
| procedure Make_Index |
| (N : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id := Empty; |
| Suffix_Index : Nat := 1; |
| In_Iter_Schm : Boolean := False); |
| -- Process an index that is given in an array declaration, an entry |
| -- family declaration or a loop iteration. The index is given by an index |
| -- declaration (a 'box'), or by a discrete range. The later can be the name |
| -- of a discrete type, or a subtype indication. |
| -- |
| -- Related_Nod is the node where the potential generated implicit types |
| -- will be inserted. The next last parameters are used for creating the |
| -- name. In_Iter_Schm is True if Make_Index is called on the discrete |
| -- subtype definition in an iteration scheme. |
| |
| procedure Make_Class_Wide_Type (T : Entity_Id); |
| -- A Class_Wide_Type is created for each tagged type definition. The |
| -- attributes of a class-wide type are inherited from those of the type T. |
| -- If T is introduced by a private declaration, the corresponding class |
| -- wide type is created at the same time, and therefore there is a private |
| -- and a full declaration for the class-wide type as well. |
| |
| function OK_For_Limited_Init_In_05 |
| (Typ : Entity_Id; |
| Exp : Node_Id) return Boolean; |
| -- Presuming Exp is an expression of an inherently limited type Typ, |
| -- returns True if the expression is allowed in an initialization context |
| -- by the rules of Ada 2005. We use the rule in RM-7.5(2.1/2), "...it is an |
| -- aggregate, a function_call, or a parenthesized expression or qualified |
| -- expression whose operand is permitted...". Note that in Ada 95 mode, |
| -- we sometimes wish to give warnings based on whether the program _would_ |
| -- be legal in Ada 2005. Note that Exp must already have been resolved, |
| -- so we can know whether it's a function call (as opposed to an indexed |
| -- component, for example). In the case where Typ is a limited interface's |
| -- class-wide type, then the expression is allowed to be of any kind if its |
| -- type is a nonlimited descendant of the interface. |
| |
| function OK_For_Limited_Init |
| (Typ : Entity_Id; |
| Exp : Node_Id) return Boolean; |
| -- Always False in Ada 95 mode. Equivalent to OK_For_Limited_Init_In_05 in |
| -- Ada 2005 mode. |
| |
| procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id); |
| -- Default and per object expressions do not freeze their components, and |
| -- must be analyzed and resolved accordingly. The analysis is done by |
| -- calling the Preanalyze_And_Resolve routine and setting the global |
| -- In_Default_Expression flag. See the documentation section entitled |
| -- "Handling of Default and Per-Object Expressions" in sem.ads for full |
| -- details. N is the expression to be analyzed, T is the expected type. |
| -- This mechanism is also used for aspect specifications that have an |
| -- expression parameter that needs similar preanalysis. |
| |
| procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id); |
| -- Wrapper on Preanalyze_Spec_Expression for assertion expressions, so that |
| -- In_Assertion_Expr can be properly adjusted. |
| |
| procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id); |
| -- Wrapper on Preanalyze_Spec_Expression for default expressions, so that |
| -- In_Default_Expr can be properly adjusted. |
| |
| procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id); |
| -- Process some semantic actions when the full view of a private type is |
| -- encountered and analyzed. The first action is to create the full views |
| -- of the dependant private subtypes. The second action is to recopy the |
| -- primitive operations of the private view (in the tagged case). |
| -- N is the N_Full_Type_Declaration node. |
| -- |
| -- Full_T is the full view of the type whose full declaration is in N. |
| -- |
| -- Priv_T is the private view of the type whose full declaration is in N. |
| |
| procedure Process_Range_Expr_In_Decl |
| (R : Node_Id; |
| T : Entity_Id; |
| Subtyp : Entity_Id := Empty; |
| Check_List : List_Id := Empty_List; |
| R_Check_Off : Boolean := False; |
| In_Iter_Schm : Boolean := False); |
| -- Process a range expression that appears in a declaration context. The |
| -- range is analyzed and resolved with the base type of the given type, and |
| -- an appropriate check for expressions in non-static contexts made on the |
| -- bounds. R is analyzed and resolved using T, so the caller should if |
| -- necessary link R into the tree before the call, and in particular in the |
| -- case of a subtype declaration, it is appropriate to set the parent |
| -- pointer of R so that the types get properly frozen. Check_List is used |
| -- when the subprogram is called from Build_Record_Init_Proc and is used to |
| -- return a set of constraint checking statements generated by the Checks |
| -- package. R_Check_Off is set to True when the call to Range_Check is to |
| -- be skipped. In_Iter_Schm is True if Process_Range_Expr_In_Decl is called |
| -- on the discrete subtype definition in an iteration scheme. |
| -- |
| -- If Subtyp is given, then the range is for the named subtype Subtyp, and |
| -- in this case the bounds are captured if necessary using this name. |
| |
| function Process_Subtype |
| (S : Node_Id; |
| Related_Nod : Node_Id; |
| Related_Id : Entity_Id := Empty; |
| Suffix : Character := ' ') return Entity_Id; |
| -- Process a subtype indication S and return corresponding entity. |
| -- Related_Nod is the node where the potential generated implicit types |
| -- will be inserted. The Related_Id and Suffix parameters are used to |
| -- build the associated Implicit type name. |
| |
| procedure Process_Discriminants |
| (N : Node_Id; |
| Prev : Entity_Id := Empty); |
| -- Process the discriminants contained in an N_Full_Type_Declaration or |
| -- N_Incomplete_Type_Decl node N. If the declaration is a completion, Prev |
| -- is entity on the partial view, on which references are posted. However, |
| -- note that Process_Discriminants is called for a completion only if |
| -- partial view had no discriminants (else we just check conformance |
| -- between the two views and do not call Process_Discriminants again |
| -- for the completion). |
| |
| function Replace_Anonymous_Access_To_Protected_Subprogram |
| (N : Node_Id) return Entity_Id; |
| -- Ada 2005 (AI-254): Create and decorate an internal full type declaration |
| -- for an anonymous access to protected subprogram. For a record component |
| -- declaration, the type is created in the enclosing scope, for an array |
| -- type declaration or an object declaration it is simply placed ahead of |
| -- this declaration. |
| |
| procedure Set_Completion_Referenced (E : Entity_Id); |
| -- If E is the completion of a private or incomplete type declaration, |
| -- or the completion of a deferred constant declaration, mark the entity |
| -- as referenced. Warnings on unused entities, if needed, go on the |
| -- partial view. |
| |
| end Sem_Ch3; |