| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S E M _ C H 8 -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2022, 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 Atree; use Atree; |
| with Debug; use Debug; |
| with Einfo; use Einfo; |
| with Einfo.Entities; use Einfo.Entities; |
| with Einfo.Utils; use Einfo.Utils; |
| with Elists; use Elists; |
| with Errout; use Errout; |
| with Exp_Disp; use Exp_Disp; |
| with Exp_Tss; use Exp_Tss; |
| with Exp_Util; use Exp_Util; |
| with Freeze; use Freeze; |
| with Ghost; use Ghost; |
| with Impunit; use Impunit; |
| with Lib; use Lib; |
| with Lib.Load; use Lib.Load; |
| with Lib.Xref; use Lib.Xref; |
| with Namet; use Namet; |
| with Namet.Sp; use Namet.Sp; |
| with Nlists; use Nlists; |
| with Nmake; use Nmake; |
| with Opt; use Opt; |
| with Output; use Output; |
| with Restrict; use Restrict; |
| with Rident; use Rident; |
| with Rtsfind; use Rtsfind; |
| with Sem; use Sem; |
| with Sem_Aux; use Sem_Aux; |
| with Sem_Cat; use Sem_Cat; |
| with Sem_Ch3; use Sem_Ch3; |
| with Sem_Ch4; use Sem_Ch4; |
| with Sem_Ch6; use Sem_Ch6; |
| with Sem_Ch10; use Sem_Ch10; |
| with Sem_Ch12; use Sem_Ch12; |
| with Sem_Ch13; use Sem_Ch13; |
| with Sem_Dim; use Sem_Dim; |
| with Sem_Disp; use Sem_Disp; |
| with Sem_Dist; use Sem_Dist; |
| with Sem_Elab; use Sem_Elab; |
| with Sem_Eval; use Sem_Eval; |
| 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 Stand; use Stand; |
| with Sinfo; use Sinfo; |
| with Sinfo.Nodes; use Sinfo.Nodes; |
| with Sinfo.Utils; use Sinfo.Utils; |
| with Sinfo.CN; use Sinfo.CN; |
| with Snames; use Snames; |
| with Style; |
| with Table; |
| with Tbuild; use Tbuild; |
| with Uintp; use Uintp; |
| with Warnsw; use Warnsw; |
| |
| package body Sem_Ch8 is |
| |
| ------------------------------------ |
| -- Visibility and Name Resolution -- |
| ------------------------------------ |
| |
| -- This package handles name resolution and the collection of possible |
| -- interpretations for overloaded names, prior to overload resolution. |
| |
| -- Name resolution is the process that establishes a mapping between source |
| -- identifiers and the entities they denote at each point in the program. |
| -- Each entity is represented by a defining occurrence. Each identifier |
| -- that denotes an entity points to the corresponding defining occurrence. |
| -- This is the entity of the applied occurrence. Each occurrence holds |
| -- an index into the names table, where source identifiers are stored. |
| |
| -- Each entry in the names table for an identifier or designator uses the |
| -- Info pointer to hold a link to the currently visible entity that has |
| -- this name (see subprograms Get_Name_Entity_Id and Set_Name_Entity_Id |
| -- in package Sem_Util). The visibility is initialized at the beginning of |
| -- semantic processing to make entities in package Standard immediately |
| -- visible. The visibility table is used in a more subtle way when |
| -- compiling subunits (see below). |
| |
| -- Entities that have the same name (i.e. homonyms) are chained. In the |
| -- case of overloaded entities, this chain holds all the possible meanings |
| -- of a given identifier. The process of overload resolution uses type |
| -- information to select from this chain the unique meaning of a given |
| -- identifier. |
| |
| -- Entities are also chained in their scope, through the Next_Entity link. |
| -- As a consequence, the name space is organized as a sparse matrix, where |
| -- each row corresponds to a scope, and each column to a source identifier. |
| -- Open scopes, that is to say scopes currently being compiled, have their |
| -- corresponding rows of entities in order, innermost scope first. |
| |
| -- The scopes of packages that are mentioned in context clauses appear in |
| -- no particular order, interspersed among open scopes. This is because |
| -- in the course of analyzing the context of a compilation, a package |
| -- declaration is first an open scope, and subsequently an element of the |
| -- context. If subunits or child units are present, a parent unit may |
| -- appear under various guises at various times in the compilation. |
| |
| -- When the compilation of the innermost scope is complete, the entities |
| -- defined therein are no longer visible. If the scope is not a package |
| -- declaration, these entities are never visible subsequently, and can be |
| -- removed from visibility chains. If the scope is a package declaration, |
| -- its visible declarations may still be accessible. Therefore the entities |
| -- defined in such a scope are left on the visibility chains, and only |
| -- their visibility (immediately visibility or potential use-visibility) |
| -- is affected. |
| |
| -- The ordering of homonyms on their chain does not necessarily follow |
| -- the order of their corresponding scopes on the scope stack. For |
| -- example, if package P and the enclosing scope both contain entities |
| -- named E, then when compiling the package body the chain for E will |
| -- hold the global entity first, and the local one (corresponding to |
| -- the current inner scope) next. As a result, name resolution routines |
| -- do not assume any relative ordering of the homonym chains, either |
| -- for scope nesting or to order of appearance of context clauses. |
| |
| -- When compiling a child unit, entities in the parent scope are always |
| -- immediately visible. When compiling the body of a child unit, private |
| -- entities in the parent must also be made immediately visible. There |
| -- are separate routines to make the visible and private declarations |
| -- visible at various times (see package Sem_Ch7). |
| |
| -- +--------+ +-----+ |
| -- | In use |-------->| EU1 |--------------------------> |
| -- +--------+ +-----+ |
| -- | | |
| -- +--------+ +-----+ +-----+ |
| -- | Stand. |---------------->| ES1 |--------------->| ES2 |---> |
| -- +--------+ +-----+ +-----+ |
| -- | | |
| -- +---------+ | +-----+ |
| -- | with'ed |------------------------------>| EW2 |---> |
| -- +---------+ | +-----+ |
| -- | | |
| -- +--------+ +-----+ +-----+ |
| -- | Scope2 |---------------->| E12 |--------------->| E22 |---> |
| -- +--------+ +-----+ +-----+ |
| -- | | |
| -- +--------+ +-----+ +-----+ |
| -- | Scope1 |---------------->| E11 |--------------->| E12 |---> |
| -- +--------+ +-----+ +-----+ |
| -- ^ | | |
| -- | | | |
| -- | +---------+ | | |
| -- | | with'ed |-----------------------------------------> |
| -- | +---------+ | | |
| -- | | | |
| -- Scope stack | | |
| -- (innermost first) | | |
| -- +----------------------------+ |
| -- Names table => | Id1 | | | | Id2 | |
| -- +----------------------------+ |
| |
| -- Name resolution must deal with several syntactic forms: simple names, |
| -- qualified names, indexed names, and various forms of calls. |
| |
| -- Each identifier points to an entry in the names table. The resolution |
| -- of a simple name consists in traversing the homonym chain, starting |
| -- from the names table. If an entry is immediately visible, it is the one |
| -- designated by the identifier. If only potentially use-visible entities |
| -- are on the chain, we must verify that they do not hide each other. If |
| -- the entity we find is overloadable, we collect all other overloadable |
| -- entities on the chain as long as they are not hidden. |
| -- |
| -- To resolve expanded names, we must find the entity at the intersection |
| -- of the entity chain for the scope (the prefix) and the homonym chain |
| -- for the selector. In general, homonym chains will be much shorter than |
| -- entity chains, so it is preferable to start from the names table as |
| -- well. If the entity found is overloadable, we must collect all other |
| -- interpretations that are defined in the scope denoted by the prefix. |
| |
| -- For records, protected types, and tasks, their local entities are |
| -- removed from visibility chains on exit from the corresponding scope. |
| -- From the outside, these entities are always accessed by selected |
| -- notation, and the entity chain for the record type, protected type, |
| -- etc. is traversed sequentially in order to find the designated entity. |
| |
| -- The discriminants of a type and the operations of a protected type or |
| -- task are unchained on exit from the first view of the type, (such as |
| -- a private or incomplete type declaration, or a protected type speci- |
| -- fication) and re-chained when compiling the second view. |
| |
| -- In the case of operators, we do not make operators on derived types |
| -- explicit. As a result, the notation P."+" may denote either a user- |
| -- defined function with name "+", or else an implicit declaration of the |
| -- operator "+" in package P. The resolution of expanded names always |
| -- tries to resolve an operator name as such an implicitly defined entity, |
| -- in addition to looking for explicit declarations. |
| |
| -- All forms of names that denote entities (simple names, expanded names, |
| -- character literals in some cases) have a Entity attribute, which |
| -- identifies the entity denoted by the name. |
| |
| --------------------- |
| -- The Scope Stack -- |
| --------------------- |
| |
| -- The Scope stack keeps track of the scopes currently been compiled. |
| -- Every entity that contains declarations (including records) is placed |
| -- on the scope stack while it is being processed, and removed at the end. |
| -- Whenever a non-package scope is exited, the entities defined therein |
| -- are removed from the visibility table, so that entities in outer scopes |
| -- become visible (see previous description). On entry to Sem, the scope |
| -- stack only contains the package Standard. As usual, subunits complicate |
| -- this picture ever so slightly. |
| |
| -- The Rtsfind mechanism can force a call to Semantics while another |
| -- compilation is in progress. The unit retrieved by Rtsfind must be |
| -- compiled in its own context, and has no access to the visibility of |
| -- the unit currently being compiled. The procedures Save_Scope_Stack and |
| -- Restore_Scope_Stack make entities in current open scopes invisible |
| -- before compiling the retrieved unit, and restore the compilation |
| -- environment afterwards. |
| |
| ------------------------ |
| -- Compiling subunits -- |
| ------------------------ |
| |
| -- Subunits must be compiled in the environment of the corresponding stub, |
| -- that is to say with the same visibility into the parent (and its |
| -- context) that is available at the point of the stub declaration, but |
| -- with the additional visibility provided by the context clause of the |
| -- subunit itself. As a result, compilation of a subunit forces compilation |
| -- of the parent (see description in lib-). At the point of the stub |
| -- declaration, Analyze is called recursively to compile the proper body of |
| -- the subunit, but without reinitializing the names table, nor the scope |
| -- stack (i.e. standard is not pushed on the stack). In this fashion the |
| -- context of the subunit is added to the context of the parent, and the |
| -- subunit is compiled in the correct environment. Note that in the course |
| -- of processing the context of a subunit, Standard will appear twice on |
| -- the scope stack: once for the parent of the subunit, and once for the |
| -- unit in the context clause being compiled. However, the two sets of |
| -- entities are not linked by homonym chains, so that the compilation of |
| -- any context unit happens in a fresh visibility environment. |
| |
| ------------------------------- |
| -- Processing of USE Clauses -- |
| ------------------------------- |
| |
| -- Every defining occurrence has a flag indicating if it is potentially use |
| -- visible. Resolution of simple names examines this flag. The processing |
| -- of use clauses consists in setting this flag on all visible entities |
| -- defined in the corresponding package. On exit from the scope of the use |
| -- clause, the corresponding flag must be reset. However, a package may |
| -- appear in several nested use clauses (pathological but legal, alas) |
| -- which forces us to use a slightly more involved scheme: |
| |
| -- a) The defining occurrence for a package holds a flag -In_Use- to |
| -- indicate that it is currently in the scope of a use clause. If a |
| -- redundant use clause is encountered, then the corresponding occurrence |
| -- of the package name is flagged -Redundant_Use-. |
| |
| -- b) On exit from a scope, the use clauses in its declarative part are |
| -- scanned. The visibility flag is reset in all entities declared in |
| -- package named in a use clause, as long as the package is not flagged |
| -- as being in a redundant use clause (in which case the outer use |
| -- clause is still in effect, and the direct visibility of its entities |
| -- must be retained). |
| |
| -- Note that entities are not removed from their homonym chains on exit |
| -- from the package specification. A subsequent use clause does not need |
| -- to rechain the visible entities, but only to establish their direct |
| -- visibility. |
| |
| ----------------------------------- |
| -- Handling private declarations -- |
| ----------------------------------- |
| |
| -- The principle that each entity has a single defining occurrence clashes |
| -- with the presence of two separate definitions for private types: the |
| -- first is the private type declaration, and second is the full type |
| -- declaration. It is important that all references to the type point to |
| -- the same defining occurrence, namely the first one. To enforce the two |
| -- separate views of the entity, the corresponding information is swapped |
| -- between the two declarations. Outside of the package, the defining |
| -- occurrence only contains the private declaration information, while in |
| -- the private part and the body of the package the defining occurrence |
| -- contains the full declaration. To simplify the swap, the defining |
| -- occurrence that currently holds the private declaration points to the |
| -- full declaration. During semantic processing the defining occurrence |
| -- also points to a list of private dependents, that is to say access types |
| -- or composite types whose designated types or component types are |
| -- subtypes or derived types of the private type in question. After the |
| -- full declaration has been seen, the private dependents are updated to |
| -- indicate that they have full definitions. |
| |
| ------------------------------------ |
| -- Handling of Undefined Messages -- |
| ------------------------------------ |
| |
| -- In normal mode, only the first use of an undefined identifier generates |
| -- a message. The table Urefs is used to record error messages that have |
| -- been issued so that second and subsequent ones do not generate further |
| -- messages. However, the second reference causes text to be added to the |
| -- original undefined message noting "(more references follow)". The |
| -- full error list option (-gnatf) forces messages to be generated for |
| -- every reference and disconnects the use of this table. |
| |
| type Uref_Entry is record |
| Node : Node_Id; |
| -- Node for identifier for which original message was posted. The |
| -- Chars field of this identifier is used to detect later references |
| -- to the same identifier. |
| |
| Err : Error_Msg_Id; |
| -- Records error message Id of original undefined message. Reset to |
| -- No_Error_Msg after the second occurrence, where it is used to add |
| -- text to the original message as described above. |
| |
| Nvis : Boolean; |
| -- Set if the message is not visible rather than undefined |
| |
| Loc : Source_Ptr; |
| -- Records location of error message. Used to make sure that we do |
| -- not consider a, b : undefined as two separate instances, which |
| -- would otherwise happen, since the parser converts this sequence |
| -- to a : undefined; b : undefined. |
| |
| end record; |
| |
| package Urefs is new Table.Table ( |
| Table_Component_Type => Uref_Entry, |
| Table_Index_Type => Nat, |
| Table_Low_Bound => 1, |
| Table_Initial => 10, |
| Table_Increment => 100, |
| Table_Name => "Urefs"); |
| |
| Candidate_Renaming : Entity_Id; |
| -- Holds a candidate interpretation that appears in a subprogram renaming |
| -- declaration and does not match the given specification, but matches at |
| -- least on the first formal. Allows better error message when given |
| -- specification omits defaulted parameters, a common error. |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| procedure Analyze_Generic_Renaming |
| (N : Node_Id; |
| K : Entity_Kind); |
| -- Common processing for all three kinds of generic renaming declarations. |
| -- Enter new name and indicate that it renames the generic unit. |
| |
| procedure Analyze_Renamed_Character |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean); |
| -- Renamed entity is given by a character literal, which must belong |
| -- to the return type of the new entity. Is_Body indicates whether the |
| -- declaration is a renaming_as_body. If the original declaration has |
| -- already been frozen (because of an intervening body, e.g.) the body of |
| -- the function must be built now. The same applies to the following |
| -- various renaming procedures. |
| |
| procedure Analyze_Renamed_Dereference |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean); |
| -- Renamed entity is given by an explicit dereference. Prefix must be a |
| -- conformant access_to_subprogram type. |
| |
| procedure Analyze_Renamed_Entry |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean); |
| -- If the renamed entity in a subprogram renaming is an entry or protected |
| -- subprogram, build a body for the new entity whose only statement is a |
| -- call to the renamed entity. |
| |
| procedure Analyze_Renamed_Family_Member |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean); |
| -- Used when the renamed entity is an indexed component. The prefix must |
| -- denote an entry family. |
| |
| procedure Analyze_Renamed_Primitive_Operation |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean); |
| -- If the renamed entity in a subprogram renaming is a primitive operation |
| -- or a class-wide operation in prefix form, save the target object, |
| -- which must be added to the list of actuals in any subsequent call. |
| -- The renaming operation is intrinsic because the compiler must in |
| -- fact generate a wrapper for it (6.3.1 (10 1/2)). |
| |
| procedure Attribute_Renaming (N : Node_Id); |
| -- Analyze renaming of attribute as subprogram. The renaming declaration N |
| -- is rewritten as a subprogram body that returns the attribute reference |
| -- applied to the formals of the function. |
| |
| procedure Set_Entity_Or_Discriminal (N : Node_Id; E : Entity_Id); |
| -- Set Entity, with style check if need be. For a discriminant reference, |
| -- replace by the corresponding discriminal, i.e. the parameter of the |
| -- initialization procedure that corresponds to the discriminant. |
| |
| procedure Check_Frozen_Renaming (N : Node_Id; Subp : Entity_Id); |
| -- A renaming_as_body may occur after the entity of the original decla- |
| -- ration has been frozen. In that case, the body of the new entity must |
| -- be built now, because the usual mechanism of building the renamed |
| -- body at the point of freezing will not work. Subp is the subprogram |
| -- for which N provides the Renaming_As_Body. |
| |
| procedure Check_In_Previous_With_Clause (N, Nam : Node_Id); |
| -- N is a use_package clause and Nam the package name, or N is a use_type |
| -- clause and Nam is the prefix of the type name. In either case, verify |
| -- that the package is visible at that point in the context: either it |
| -- appears in a previous with_clause, or because it is a fully qualified |
| -- name and the root ancestor appears in a previous with_clause. |
| |
| procedure Check_Library_Unit_Renaming (N : Node_Id; Old_E : Entity_Id); |
| -- Verify that the entity in a renaming declaration that is a library unit |
| -- is itself a library unit and not a nested unit or subunit. Also check |
| -- that if the renaming is a child unit of a generic parent, then the |
| -- renamed unit must also be a child unit of that parent. Finally, verify |
| -- that a renamed generic unit is not an implicit child declared within |
| -- an instance of the parent. |
| |
| procedure Chain_Use_Clause (N : Node_Id); |
| -- Chain use clause onto list of uses clauses headed by First_Use_Clause in |
| -- the proper scope table entry. This is usually the current scope, but it |
| -- will be an inner scope when installing the use clauses of the private |
| -- declarations of a parent unit prior to compiling the private part of a |
| -- child unit. This chain is traversed when installing/removing use clauses |
| -- when compiling a subunit or instantiating a generic body on the fly, |
| -- when it is necessary to save and restore full environments. |
| |
| function Enclosing_Instance return Entity_Id; |
| -- In an instance nested within another one, several semantic checks are |
| -- unnecessary because the legality of the nested instance has been checked |
| -- in the enclosing generic unit. This applies in particular to legality |
| -- checks on actuals for formal subprograms of the inner instance, which |
| -- are checked as subprogram renamings, and may be complicated by confusion |
| -- in private/full views. This function returns the instance enclosing the |
| -- current one if there is such, else it returns Empty. |
| -- |
| -- If the renaming determines the entity for the default of a formal |
| -- subprogram nested within another instance, choose the innermost |
| -- candidate. This is because if the formal has a box, and we are within |
| -- an enclosing instance where some candidate interpretations are local |
| -- to this enclosing instance, we know that the default was properly |
| -- resolved when analyzing the generic, so we prefer the local |
| -- candidates to those that are external. This is not always the case |
| -- but is a reasonable heuristic on the use of nested generics. The |
| -- proper solution requires a full renaming model. |
| |
| function Entity_Of_Unit (U : Node_Id) return Entity_Id; |
| -- Return the appropriate entity for determining which unit has a deeper |
| -- scope: the defining entity for U, unless U is a package instance, in |
| -- which case we retrieve the entity of the instance spec. |
| |
| procedure Error_Missing_With_Of_Known_Unit (Pkg : Node_Id); |
| -- Display an error message denoting a "with" is missing for a given known |
| -- package Pkg with its full path name. |
| |
| procedure Find_Expanded_Name (N : Node_Id); |
| -- The input is a selected component known to be an expanded name. Verify |
| -- legality of selector given the scope denoted by prefix, and change node |
| -- N into a expanded name with a properly set Entity field. |
| |
| function Find_First_Use (Use_Clause : Node_Id) return Node_Id; |
| -- Find the most previous use clause (that is, the first one to appear in |
| -- the source) by traversing the previous clause chain that exists in both |
| -- N_Use_Package_Clause nodes and N_Use_Type_Clause nodes. |
| |
| function Find_Renamed_Entity |
| (N : Node_Id; |
| Nam : Node_Id; |
| New_S : Entity_Id; |
| Is_Actual : Boolean := False) return Entity_Id; |
| -- Find the renamed entity that corresponds to the given parameter profile |
| -- in a subprogram renaming declaration. The renamed entity may be an |
| -- operator, a subprogram, an entry, or a protected operation. Is_Actual |
| -- indicates that the renaming is the one generated for an actual subpro- |
| -- gram in an instance, for which special visibility checks apply. |
| |
| function Has_Implicit_Character_Literal (N : Node_Id) return Boolean; |
| -- Find a type derived from Character or Wide_Character in the prefix of N. |
| -- Used to resolved qualified names whose selector is a character literal. |
| |
| function Has_Private_With (E : Entity_Id) return Boolean; |
| -- Ada 2005 (AI-262): Determines if the current compilation unit has a |
| -- private with on E. |
| |
| function Has_Components (Typ : Entity_Id) return Boolean; |
| -- Determine if given type has components, i.e. is either a record type or |
| -- type or a type that has discriminants. |
| |
| function Has_Implicit_Operator (N : Node_Id) return Boolean; |
| -- N is an expanded name whose selector is an operator name (e.g. P."+"). |
| -- Determine if N denotes an operator implicitly declared in prefix P: P's |
| -- declarative part contains an implicit declaration of an operator if it |
| -- has a declaration of a type to which one of the predefined operators |
| -- apply. The existence of this routine is an implementation artifact. A |
| -- more straightforward but more space-consuming choice would be to make |
| -- all inherited operators explicit in the symbol table. |
| |
| procedure Inherit_Renamed_Profile (New_S : Entity_Id; Old_S : Entity_Id); |
| -- A subprogram defined by a renaming declaration inherits the parameter |
| -- profile of the renamed entity. The subtypes given in the subprogram |
| -- specification are discarded and replaced with those of the renamed |
| -- subprogram, which are then used to recheck the default values. |
| |
| function Most_Descendant_Use_Clause |
| (Clause1 : Entity_Id; |
| Clause2 : Entity_Id) return Entity_Id; |
| -- Determine which use clause parameter is the most descendant in terms of |
| -- scope. |
| |
| procedure Premature_Usage (N : Node_Id); |
| -- Diagnose usage of an entity before it is visible |
| |
| procedure Use_One_Package |
| (N : Node_Id; |
| Pack_Name : Entity_Id := Empty; |
| Force : Boolean := False); |
| -- Make visible entities declared in package P potentially use-visible |
| -- in the current context. Also used in the analysis of subunits, when |
| -- re-installing use clauses of parent units. N is the use_clause that |
| -- names P (and possibly other packages). |
| |
| procedure Use_One_Type |
| (Id : Node_Id; |
| Installed : Boolean := False; |
| Force : Boolean := False); |
| -- Id is the subtype mark from a use_type_clause. This procedure makes |
| -- the primitive operators of the type potentially use-visible. The |
| -- boolean flag Installed indicates that the clause is being reinstalled |
| -- after previous analysis, and primitive operations are already chained |
| -- on the Used_Operations list of the clause. |
| |
| procedure Write_Info; |
| -- Write debugging information on entities declared in current scope |
| |
| -------------------------------- |
| -- Analyze_Exception_Renaming -- |
| -------------------------------- |
| |
| -- The language only allows a single identifier, but the tree holds an |
| -- identifier list. The parser has already issued an error message if |
| -- there is more than one element in the list. |
| |
| procedure Analyze_Exception_Renaming (N : Node_Id) is |
| Id : constant Entity_Id := Defining_Entity (N); |
| Nam : constant Node_Id := Name (N); |
| |
| begin |
| Enter_Name (Id); |
| Analyze (Nam); |
| |
| Mutate_Ekind (Id, E_Exception); |
| Set_Etype (Id, Standard_Exception_Type); |
| Set_Is_Pure (Id, Is_Pure (Current_Scope)); |
| |
| if Is_Entity_Name (Nam) |
| and then Present (Entity (Nam)) |
| and then Ekind (Entity (Nam)) = E_Exception |
| then |
| if Present (Renamed_Entity (Entity (Nam))) then |
| Set_Renamed_Entity (Id, Renamed_Entity (Entity (Nam))); |
| else |
| Set_Renamed_Entity (Id, Entity (Nam)); |
| end if; |
| |
| -- The exception renaming declaration may become Ghost if it renames |
| -- a Ghost entity. |
| |
| Mark_Ghost_Renaming (N, Entity (Nam)); |
| else |
| Error_Msg_N ("invalid exception name in renaming", Nam); |
| end if; |
| |
| -- Implementation-defined aspect specifications can appear in a renaming |
| -- declaration, but not language-defined ones. The call to procedure |
| -- Analyze_Aspect_Specifications will take care of this error check. |
| |
| if Has_Aspects (N) then |
| Analyze_Aspect_Specifications (N, Id); |
| end if; |
| end Analyze_Exception_Renaming; |
| |
| --------------------------- |
| -- Analyze_Expanded_Name -- |
| --------------------------- |
| |
| procedure Analyze_Expanded_Name (N : Node_Id) is |
| begin |
| -- If the entity pointer is already set, this is an internal node, or a |
| -- node that is analyzed more than once, after a tree modification. In |
| -- such a case there is no resolution to perform, just set the type. In |
| -- either case, start by analyzing the prefix. |
| |
| Analyze (Prefix (N)); |
| |
| if Present (Entity (N)) then |
| if Is_Type (Entity (N)) then |
| Set_Etype (N, Entity (N)); |
| else |
| Set_Etype (N, Etype (Entity (N))); |
| end if; |
| |
| else |
| Find_Expanded_Name (N); |
| end if; |
| |
| -- In either case, propagate dimension of entity to expanded name |
| |
| Analyze_Dimension (N); |
| end Analyze_Expanded_Name; |
| |
| --------------------------------------- |
| -- Analyze_Generic_Function_Renaming -- |
| --------------------------------------- |
| |
| procedure Analyze_Generic_Function_Renaming (N : Node_Id) is |
| begin |
| Analyze_Generic_Renaming (N, E_Generic_Function); |
| end Analyze_Generic_Function_Renaming; |
| |
| -------------------------------------- |
| -- Analyze_Generic_Package_Renaming -- |
| -------------------------------------- |
| |
| procedure Analyze_Generic_Package_Renaming (N : Node_Id) is |
| begin |
| -- Test for the Text_IO special unit case here, since we may be renaming |
| -- one of the subpackages of Text_IO, then join common routine. |
| |
| Check_Text_IO_Special_Unit (Name (N)); |
| |
| Analyze_Generic_Renaming (N, E_Generic_Package); |
| end Analyze_Generic_Package_Renaming; |
| |
| ---------------------------------------- |
| -- Analyze_Generic_Procedure_Renaming -- |
| ---------------------------------------- |
| |
| procedure Analyze_Generic_Procedure_Renaming (N : Node_Id) is |
| begin |
| Analyze_Generic_Renaming (N, E_Generic_Procedure); |
| end Analyze_Generic_Procedure_Renaming; |
| |
| ------------------------------ |
| -- Analyze_Generic_Renaming -- |
| ------------------------------ |
| |
| procedure Analyze_Generic_Renaming |
| (N : Node_Id; |
| K : Entity_Kind) |
| is |
| New_P : constant Entity_Id := Defining_Entity (N); |
| Inst : Boolean := False; |
| Old_P : Entity_Id; |
| |
| begin |
| if Name (N) = Error then |
| return; |
| end if; |
| |
| Generate_Definition (New_P); |
| |
| if Current_Scope /= Standard_Standard then |
| Set_Is_Pure (New_P, Is_Pure (Current_Scope)); |
| end if; |
| |
| if Nkind (Name (N)) = N_Selected_Component then |
| Check_Generic_Child_Unit (Name (N), Inst); |
| else |
| Analyze (Name (N)); |
| end if; |
| |
| if not Is_Entity_Name (Name (N)) then |
| Error_Msg_N ("expect entity name in renaming declaration", Name (N)); |
| Old_P := Any_Id; |
| else |
| Old_P := Entity (Name (N)); |
| end if; |
| |
| Enter_Name (New_P); |
| Mutate_Ekind (New_P, K); |
| |
| if Etype (Old_P) = Any_Type then |
| null; |
| |
| elsif Ekind (Old_P) /= K then |
| Error_Msg_N ("invalid generic unit name", Name (N)); |
| |
| else |
| if Present (Renamed_Entity (Old_P)) then |
| Set_Renamed_Entity (New_P, Renamed_Entity (Old_P)); |
| else |
| Set_Renamed_Entity (New_P, Old_P); |
| end if; |
| |
| -- The generic renaming declaration may become Ghost if it renames a |
| -- Ghost entity. |
| |
| Mark_Ghost_Renaming (N, Old_P); |
| |
| Set_Is_Pure (New_P, Is_Pure (Old_P)); |
| Set_Is_Preelaborated (New_P, Is_Preelaborated (Old_P)); |
| |
| Set_Etype (New_P, Etype (Old_P)); |
| Set_Has_Completion (New_P); |
| |
| if In_Open_Scopes (Old_P) then |
| Error_Msg_N ("within its scope, generic denotes its instance", N); |
| end if; |
| |
| -- For subprograms, propagate the Intrinsic flag, to allow, e.g. |
| -- renamings and subsequent instantiations of Unchecked_Conversion. |
| |
| if Is_Generic_Subprogram (Old_P) then |
| Set_Is_Intrinsic_Subprogram |
| (New_P, Is_Intrinsic_Subprogram (Old_P)); |
| end if; |
| |
| Check_Library_Unit_Renaming (N, Old_P); |
| end if; |
| |
| -- Implementation-defined aspect specifications can appear in a renaming |
| -- declaration, but not language-defined ones. The call to procedure |
| -- Analyze_Aspect_Specifications will take care of this error check. |
| |
| if Has_Aspects (N) then |
| Analyze_Aspect_Specifications (N, New_P); |
| end if; |
| end Analyze_Generic_Renaming; |
| |
| ----------------------------- |
| -- Analyze_Object_Renaming -- |
| ----------------------------- |
| |
| procedure Analyze_Object_Renaming (N : Node_Id) is |
| Id : constant Entity_Id := Defining_Identifier (N); |
| Loc : constant Source_Ptr := Sloc (N); |
| Nam : constant Node_Id := Name (N); |
| Is_Object_Ref : Boolean; |
| Dec : Node_Id; |
| T : Entity_Id; |
| T2 : Entity_Id; |
| Q : Node_Id; |
| |
| procedure Check_Constrained_Object; |
| -- If the nominal type is unconstrained but the renamed object is |
| -- constrained, as can happen with renaming an explicit dereference or |
| -- a function return, build a constrained subtype from the object. If |
| -- the renaming is for a formal in an accept statement, the analysis |
| -- has already established its actual subtype. This is only relevant |
| -- if the renamed object is an explicit dereference. |
| |
| function Get_Object_Name (Nod : Node_Id) return Node_Id; |
| -- Obtain the name of the object from node Nod which is being renamed by |
| -- the object renaming declaration N. |
| |
| function Find_Raise_Node (N : Node_Id) return Traverse_Result; |
| -- Process one node in search for N_Raise_xxx_Error nodes. |
| -- Return Abandon if found, OK otherwise. |
| |
| --------------------- |
| -- Find_Raise_Node -- |
| --------------------- |
| |
| function Find_Raise_Node (N : Node_Id) return Traverse_Result is |
| begin |
| if Nkind (N) in N_Raise_xxx_Error then |
| return Abandon; |
| else |
| return OK; |
| end if; |
| end Find_Raise_Node; |
| |
| ------------------------ |
| -- No_Raise_xxx_Error -- |
| ------------------------ |
| |
| function No_Raise_xxx_Error is new Traverse_Func (Find_Raise_Node); |
| -- Traverse tree to look for a N_Raise_xxx_Error node and returns |
| -- Abandon if so and OK if none found. |
| |
| ------------------------------ |
| -- Check_Constrained_Object -- |
| ------------------------------ |
| |
| procedure Check_Constrained_Object is |
| Typ : constant Entity_Id := Etype (Nam); |
| Subt : Entity_Id; |
| Loop_Scheme : Node_Id; |
| |
| begin |
| if Nkind (Nam) in N_Function_Call | N_Explicit_Dereference |
| and then Is_Composite_Type (Typ) |
| and then not Is_Constrained (Typ) |
| and then not Has_Unknown_Discriminants (Typ) |
| and then Expander_Active |
| then |
| -- If Actual_Subtype is already set, nothing to do |
| |
| if Ekind (Id) in E_Variable | E_Constant |
| and then Present (Actual_Subtype (Id)) |
| then |
| null; |
| |
| -- A renaming of an unchecked union has no actual subtype |
| |
| elsif Is_Unchecked_Union (Typ) then |
| null; |
| |
| -- If a record is limited its size is invariant. This is the case |
| -- in particular with record types with an access discriminant |
| -- that are used in iterators. This is an optimization, but it |
| -- also prevents typing anomalies when the prefix is further |
| -- expanded. |
| |
| -- Note that we cannot just use the Is_Limited_Record flag because |
| -- it does not apply to records with limited components, for which |
| -- this syntactic flag is not set, but whose size is also fixed. |
| |
| -- Note also that we need to build the constrained subtype for an |
| -- array in order to make the bounds explicit in most cases, but |
| -- not if the object comes from an extended return statement, as |
| -- this would create dangling references to them later on. |
| |
| elsif Is_Limited_Type (Typ) |
| and then (not Is_Array_Type (Typ) or else Is_Return_Object (Id)) |
| then |
| null; |
| |
| else |
| Subt := Make_Temporary (Loc, 'T'); |
| Remove_Side_Effects (Nam); |
| Insert_Action (N, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Subt, |
| Subtype_Indication => |
| Make_Subtype_From_Expr (Nam, Typ))); |
| Rewrite (Subtype_Mark (N), New_Occurrence_Of (Subt, Loc)); |
| Set_Etype (Nam, Subt); |
| |
| -- Suppress discriminant checks on this subtype if the original |
| -- type has defaulted discriminants and Id is a "for of" loop |
| -- iterator. |
| |
| if Has_Defaulted_Discriminants (Typ) |
| and then Nkind (Original_Node (Parent (N))) = N_Loop_Statement |
| then |
| Loop_Scheme := Iteration_Scheme (Original_Node (Parent (N))); |
| |
| if Present (Loop_Scheme) |
| and then Present (Iterator_Specification (Loop_Scheme)) |
| and then |
| Defining_Identifier |
| (Iterator_Specification (Loop_Scheme)) = Id |
| then |
| Set_Checks_May_Be_Suppressed (Subt); |
| Push_Local_Suppress_Stack_Entry |
| (Entity => Subt, |
| Check => Discriminant_Check, |
| Suppress => True); |
| end if; |
| end if; |
| |
| -- Freeze subtype at once, to prevent order of elaboration |
| -- issues in the backend. The renamed object exists, so its |
| -- type is already frozen in any case. |
| |
| Freeze_Before (N, Subt); |
| end if; |
| end if; |
| end Check_Constrained_Object; |
| |
| --------------------- |
| -- Get_Object_Name -- |
| --------------------- |
| |
| function Get_Object_Name (Nod : Node_Id) return Node_Id is |
| Obj_Nam : Node_Id; |
| |
| begin |
| Obj_Nam := Nod; |
| while Present (Obj_Nam) loop |
| case Nkind (Obj_Nam) is |
| when N_Attribute_Reference |
| | N_Explicit_Dereference |
| | N_Indexed_Component |
| | N_Slice |
| => |
| Obj_Nam := Prefix (Obj_Nam); |
| |
| when N_Selected_Component => |
| Obj_Nam := Selector_Name (Obj_Nam); |
| |
| when N_Qualified_Expression | N_Type_Conversion => |
| Obj_Nam := Expression (Obj_Nam); |
| |
| when others => |
| exit; |
| end case; |
| end loop; |
| |
| return Obj_Nam; |
| end Get_Object_Name; |
| |
| -- Start of processing for Analyze_Object_Renaming |
| |
| begin |
| if Nam = Error then |
| return; |
| end if; |
| |
| Set_Is_Pure (Id, Is_Pure (Current_Scope)); |
| Enter_Name (Id); |
| |
| -- The renaming of a component that depends on a discriminant requires |
| -- an actual subtype, because in subsequent use of the object Gigi will |
| -- be unable to locate the actual bounds. This explicit step is required |
| -- when the renaming is generated in removing side effects of an |
| -- already-analyzed expression. |
| |
| if Nkind (Nam) = N_Selected_Component and then Analyzed (Nam) then |
| |
| -- The object renaming declaration may become Ghost if it renames a |
| -- Ghost entity. |
| |
| if Is_Entity_Name (Nam) then |
| Mark_Ghost_Renaming (N, Entity (Nam)); |
| end if; |
| |
| T := Etype (Nam); |
| Dec := Build_Actual_Subtype_Of_Component (Etype (Nam), Nam); |
| |
| if Present (Dec) then |
| Insert_Action (N, Dec); |
| T := Defining_Identifier (Dec); |
| Set_Etype (Nam, T); |
| end if; |
| elsif Present (Subtype_Mark (N)) |
| or else No (Access_Definition (N)) |
| then |
| if Present (Subtype_Mark (N)) then |
| Find_Type (Subtype_Mark (N)); |
| T := Entity (Subtype_Mark (N)); |
| Analyze (Nam); |
| |
| -- AI12-0275: Case of object renaming without a subtype_mark |
| |
| else |
| Analyze (Nam); |
| |
| -- Normal case of no overloading in object name |
| |
| if not Is_Overloaded (Nam) then |
| |
| -- Catch error cases (such as attempting to rename a procedure |
| -- or package) using the shorthand form. |
| |
| if No (Etype (Nam)) |
| or else Etype (Nam) = Standard_Void_Type |
| then |
| Error_Msg_N |
| ("object name or value expected in renaming", Nam); |
| |
| Mutate_Ekind (Id, E_Variable); |
| Set_Etype (Id, Any_Type); |
| |
| return; |
| |
| else |
| T := Etype (Nam); |
| end if; |
| |
| -- Case of overloaded name, which will be illegal if there's more |
| -- than one acceptable interpretation (such as overloaded function |
| -- calls). |
| |
| else |
| declare |
| I : Interp_Index; |
| I1 : Interp_Index; |
| It : Interp; |
| It1 : Interp; |
| Nam1 : Entity_Id; |
| |
| begin |
| -- More than one candidate interpretation is available |
| |
| -- Remove procedure calls, which syntactically cannot appear |
| -- in this context, but which cannot be removed by type |
| -- checking, because the context does not impose a type. |
| |
| Get_First_Interp (Nam, I, It); |
| while Present (It.Typ) loop |
| if It.Typ = Standard_Void_Type then |
| Remove_Interp (I); |
| end if; |
| |
| Get_Next_Interp (I, It); |
| end loop; |
| |
| Get_First_Interp (Nam, I, It); |
| I1 := I; |
| It1 := It; |
| |
| -- If there's no type present, we have an error case (such |
| -- as overloaded procedures named in the object renaming). |
| |
| if No (It.Typ) then |
| Error_Msg_N |
| ("object name or value expected in renaming", Nam); |
| |
| Mutate_Ekind (Id, E_Variable); |
| Set_Etype (Id, Any_Type); |
| |
| return; |
| end if; |
| |
| Get_Next_Interp (I, It); |
| |
| if Present (It.Typ) then |
| Nam1 := It1.Nam; |
| It1 := Disambiguate (Nam, I1, I, Any_Type); |
| |
| if It1 = No_Interp then |
| Error_Msg_N ("ambiguous name in object renaming", Nam); |
| |
| Error_Msg_Sloc := Sloc (It.Nam); |
| Error_Msg_N ("\\possible interpretation#!", Nam); |
| |
| Error_Msg_Sloc := Sloc (Nam1); |
| Error_Msg_N ("\\possible interpretation#!", Nam); |
| |
| return; |
| end if; |
| end if; |
| |
| Set_Etype (Nam, It1.Typ); |
| T := It1.Typ; |
| end; |
| end if; |
| |
| if Etype (Nam) = Standard_Exception_Type then |
| Error_Msg_N |
| ("exception requires a subtype mark in renaming", Nam); |
| return; |
| end if; |
| end if; |
| |
| -- The object renaming declaration may become Ghost if it renames a |
| -- Ghost entity. |
| |
| if Is_Entity_Name (Nam) then |
| Mark_Ghost_Renaming (N, Entity (Nam)); |
| end if; |
| |
| -- Check against AI12-0401 here before Resolve may rewrite Nam and |
| -- potentially generate spurious warnings. |
| |
| -- In the case where the object_name is a qualified_expression with |
| -- a nominal subtype T and whose expression is a name that denotes |
| -- an object Q: |
| -- * if T is an elementary subtype, then: |
| -- * Q shall be a constant other than a dereference of an access |
| -- type; or |
| -- * the nominal subtype of Q shall be statically compatible with |
| -- T; or |
| -- * T shall statically match the base subtype of its type if |
| -- scalar, or the first subtype of its type if an access type. |
| -- * if T is a composite subtype, then Q shall be known to be |
| -- constrained or T shall statically match the first subtype of |
| -- its type. |
| |
| if Nkind (Nam) = N_Qualified_Expression |
| and then Is_Object_Reference (Expression (Nam)) |
| then |
| Q := Expression (Nam); |
| |
| if (Is_Elementary_Type (T) |
| and then |
| not ((not Is_Variable (Q) |
| and then Nkind (Q) /= N_Explicit_Dereference) |
| or else Subtypes_Statically_Compatible (Etype (Q), T) |
| or else (Is_Scalar_Type (T) |
| and then Subtypes_Statically_Match |
| (T, Base_Type (T))) |
| or else (Is_Access_Type (T) |
| and then Subtypes_Statically_Match |
| (T, First_Subtype (T))))) |
| or else (Is_Composite_Type (T) |
| and then |
| |
| -- If Q is an aggregate, Is_Constrained may not be set |
| -- yet and its type may not be resolved yet. |
| -- This doesn't quite correspond to the complex notion |
| -- of "known to be constrained" but this is good enough |
| -- for a rule which is in any case too complex. |
| |
| not (Is_Constrained (Etype (Q)) |
| or else Nkind (Q) = N_Aggregate |
| or else Subtypes_Statically_Match |
| (T, First_Subtype (T)))) |
| then |
| Error_Msg_N |
| ("subtype of renamed qualified expression does not " & |
| "statically match", N); |
| return; |
| end if; |
| end if; |
| |
| Resolve (Nam, T); |
| |
| -- If the renamed object is a function call of a limited type, |
| -- the expansion of the renaming is complicated by the presence |
| -- of various temporaries and subtypes that capture constraints |
| -- of the renamed object. Rewrite node as an object declaration, |
| -- whose expansion is simpler. Given that the object is limited |
| -- there is no copy involved and no performance hit. |
| |
| if Nkind (Nam) = N_Function_Call |
| and then Is_Limited_View (Etype (Nam)) |
| and then not Is_Constrained (Etype (Nam)) |
| and then Comes_From_Source (N) |
| then |
| Set_Etype (Id, T); |
| Mutate_Ekind (Id, E_Constant); |
| Rewrite (N, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Id, |
| Constant_Present => True, |
| Object_Definition => New_Occurrence_Of (Etype (Nam), Loc), |
| Expression => Relocate_Node (Nam))); |
| return; |
| end if; |
| |
| -- Ada 2012 (AI05-149): Reject renaming of an anonymous access object |
| -- when renaming declaration has a named access type. The Ada 2012 |
| -- coverage rules allow an anonymous access type in the context of |
| -- an expected named general access type, but the renaming rules |
| -- require the types to be the same. (An exception is when the type |
| -- of the renaming is also an anonymous access type, which can only |
| -- happen due to a renaming created by the expander.) |
| |
| if Nkind (Nam) = N_Type_Conversion |
| and then not Comes_From_Source (Nam) |
| and then Is_Anonymous_Access_Type (Etype (Expression (Nam))) |
| and then not Is_Anonymous_Access_Type (T) |
| then |
| Error_Msg_NE |
| ("cannot rename anonymous access object " |
| & "as a named access type", Expression (Nam), T); |
| end if; |
| |
| -- Check that a class-wide object is not being renamed as an object |
| -- of a specific type. The test for access types is needed to exclude |
| -- cases where the renamed object is a dynamically tagged access |
| -- result, such as occurs in certain expansions. |
| |
| if Is_Tagged_Type (T) then |
| Check_Dynamically_Tagged_Expression |
| (Expr => Nam, |
| Typ => T, |
| Related_Nod => N); |
| end if; |
| |
| -- Ada 2005 (AI-230/AI-254): Access renaming |
| |
| else pragma Assert (Present (Access_Definition (N))); |
| T := |
| Access_Definition |
| (Related_Nod => N, |
| N => Access_Definition (N)); |
| |
| Analyze (Nam); |
| |
| -- The object renaming declaration may become Ghost if it renames a |
| -- Ghost entity. |
| |
| if Is_Entity_Name (Nam) then |
| Mark_Ghost_Renaming (N, Entity (Nam)); |
| end if; |
| |
| -- Ada 2005 AI05-105: if the declaration has an anonymous access |
| -- type, the renamed object must also have an anonymous type, and |
| -- this is a name resolution rule. This was implicit in the last part |
| -- of the first sentence in 8.5.1(3/2), and is made explicit by this |
| -- recent AI. |
| |
| if not Is_Overloaded (Nam) then |
| if Ekind (Etype (Nam)) /= Ekind (T) then |
| Error_Msg_N |
| ("expect anonymous access type in object renaming", N); |
| end if; |
| |
| else |
| declare |
| I : Interp_Index; |
| It : Interp; |
| Typ : Entity_Id := Empty; |
| Seen : Boolean := False; |
| |
| begin |
| Get_First_Interp (Nam, I, It); |
| while Present (It.Typ) loop |
| |
| -- Renaming is ambiguous if more than one candidate |
| -- interpretation is type-conformant with the context. |
| |
| if Ekind (It.Typ) = Ekind (T) then |
| if Ekind (T) = E_Anonymous_Access_Subprogram_Type |
| and then |
| Type_Conformant |
| (Designated_Type (T), Designated_Type (It.Typ)) |
| then |
| if not Seen then |
| Seen := True; |
| else |
| Error_Msg_N |
| ("ambiguous expression in renaming", Nam); |
| end if; |
| |
| elsif Ekind (T) = E_Anonymous_Access_Type |
| and then |
| Covers (Designated_Type (T), Designated_Type (It.Typ)) |
| then |
| if not Seen then |
| Seen := True; |
| else |
| Error_Msg_N |
| ("ambiguous expression in renaming", Nam); |
| end if; |
| end if; |
| |
| if Covers (T, It.Typ) then |
| Typ := It.Typ; |
| Set_Etype (Nam, Typ); |
| Set_Is_Overloaded (Nam, False); |
| end if; |
| end if; |
| |
| Get_Next_Interp (I, It); |
| end loop; |
| end; |
| end if; |
| |
| Resolve (Nam, T); |
| |
| -- Do not perform the legality checks below when the resolution of |
| -- the renaming name failed because the associated type is Any_Type. |
| |
| if Etype (Nam) = Any_Type then |
| null; |
| |
| -- Ada 2005 (AI-231): In the case where the type is defined by an |
| -- access_definition, the renamed entity shall be of an access-to- |
| -- constant type if and only if the access_definition defines an |
| -- access-to-constant type. ARM 8.5.1(4) |
| |
| elsif Constant_Present (Access_Definition (N)) |
| and then not Is_Access_Constant (Etype (Nam)) |
| then |
| Error_Msg_N |
| ("(Ada 2005): the renamed object is not access-to-constant " |
| & "(RM 8.5.1(6))", N); |
| |
| elsif not Constant_Present (Access_Definition (N)) |
| and then Is_Access_Constant (Etype (Nam)) |
| then |
| Error_Msg_N |
| ("(Ada 2005): the renamed object is not access-to-variable " |
| & "(RM 8.5.1(6))", N); |
| end if; |
| |
| if Is_Access_Subprogram_Type (Etype (Nam)) then |
| Check_Subtype_Conformant |
| (Designated_Type (T), Designated_Type (Etype (Nam))); |
| |
| elsif not Subtypes_Statically_Match |
| (Designated_Type (T), |
| Available_View (Designated_Type (Etype (Nam)))) |
| then |
| Error_Msg_N |
| ("subtype of renamed object does not statically match", N); |
| end if; |
| end if; |
| |
| -- Special processing for renaming function return object. Some errors |
| -- and warnings are produced only for calls that come from source. |
| |
| if Nkind (Nam) = N_Function_Call then |
| case Ada_Version is |
| |
| -- Usage is illegal in Ada 83, but renamings are also introduced |
| -- during expansion, and error does not apply to those. |
| |
| when Ada_83 => |
| if Comes_From_Source (N) then |
| Error_Msg_N |
| ("(Ada 83) cannot rename function return object", Nam); |
| end if; |
| |
| -- In Ada 95, warn for odd case of renaming parameterless function |
| -- call if this is not a limited type (where this is useful). |
| |
| when others => |
| if Warn_On_Object_Renames_Function |
| and then No (Parameter_Associations (Nam)) |
| and then not Is_Limited_Type (Etype (Nam)) |
| and then Comes_From_Source (Nam) |
| then |
| Error_Msg_N |
| ("renaming function result object is suspicious?.r?", Nam); |
| Error_Msg_NE |
| ("\function & will be called only once?.r?", Nam, |
| Entity (Name (Nam))); |
| Error_Msg_N -- CODEFIX |
| ("\suggest using an initialized constant object " |
| & "instead?.r?", Nam); |
| end if; |
| end case; |
| end if; |
| |
| Check_Constrained_Object; |
| |
| -- An object renaming requires an exact match of the type. Class-wide |
| -- matching is not allowed. |
| |
| if Is_Class_Wide_Type (T) |
| and then Base_Type (Etype (Nam)) /= Base_Type (T) |
| then |
| Wrong_Type (Nam, T); |
| end if; |
| |
| -- We must search for an actual subtype here so that the bounds of |
| -- objects of unconstrained types don't get dropped on the floor - such |
| -- as with renamings of formal parameters. |
| |
| T2 := Get_Actual_Subtype_If_Available (Nam); |
| |
| -- Ada 2005 (AI-326): Handle wrong use of incomplete type |
| |
| if Nkind (Nam) = N_Explicit_Dereference |
| and then Ekind (Etype (T2)) = E_Incomplete_Type |
| then |
| Error_Msg_NE ("invalid use of incomplete type&", Id, T2); |
| return; |
| |
| elsif Ekind (Etype (T)) = E_Incomplete_Type then |
| Error_Msg_NE ("invalid use of incomplete type&", Id, T); |
| return; |
| end if; |
| |
| if Ada_Version >= Ada_2005 and then Nkind (Nam) in N_Has_Entity then |
| declare |
| Nam_Ent : constant Entity_Id := Entity (Get_Object_Name (Nam)); |
| Nam_Decl : constant Node_Id := Declaration_Node (Nam_Ent); |
| |
| begin |
| if Has_Null_Exclusion (N) |
| and then not Has_Null_Exclusion (Nam_Decl) |
| then |
| -- Ada 2005 (AI-423): If the object name denotes a generic |
| -- formal object of a generic unit G, and the object renaming |
| -- declaration occurs within the body of G or within the body |
| -- of a generic unit declared within the declarative region |
| -- of G, then the declaration of the formal object of G must |
| -- have a null exclusion or a null-excluding subtype. |
| |
| if Is_Formal_Object (Nam_Ent) |
| and then In_Generic_Scope (Id) |
| then |
| if not Can_Never_Be_Null (Etype (Nam_Ent)) then |
| Error_Msg_N |
| ("object does not exclude `NULL` " |
| & "(RM 8.5.1(4.6/2))", N); |
| |
| elsif In_Package_Body (Scope (Id)) then |
| Error_Msg_N |
| ("formal object does not have a null exclusion" |
| & "(RM 8.5.1(4.6/2))", N); |
| end if; |
| |
| -- Ada 2005 (AI-423): Otherwise, the subtype of the object name |
| -- shall exclude null. |
| |
| elsif not Can_Never_Be_Null (Etype (Nam_Ent)) then |
| Error_Msg_N |
| ("object does not exclude `NULL` " |
| & "(RM 8.5.1(4.6/2))", N); |
| |
| -- An instance is illegal if it contains a renaming that |
| -- excludes null, and the actual does not. The renaming |
| -- declaration has already indicated that the declaration |
| -- of the renamed actual in the instance will raise |
| -- constraint_error. |
| |
| elsif Nkind (Nam_Decl) = N_Object_Declaration |
| and then In_Instance |
| and then |
| Present (Corresponding_Generic_Association (Nam_Decl)) |
| and then Nkind (Expression (Nam_Decl)) = |
| N_Raise_Constraint_Error |
| then |
| Error_Msg_N |
| ("actual does not exclude `NULL` (RM 8.5.1(4.6/2))", N); |
| |
| -- Finally, if there is a null exclusion, the subtype mark |
| -- must not be null-excluding. |
| |
| elsif No (Access_Definition (N)) |
| and then Can_Never_Be_Null (T) |
| then |
| Error_Msg_NE |
| ("`NOT NULL` not allowed (& already excludes null)", |
| N, T); |
| |
| end if; |
| |
| elsif Can_Never_Be_Null (T) |
| and then not Can_Never_Be_Null (Etype (Nam_Ent)) |
| then |
| Error_Msg_N |
| ("object does not exclude `NULL` (RM 8.5.1(4.6/2))", N); |
| |
| elsif Has_Null_Exclusion (N) |
| and then No (Access_Definition (N)) |
| and then Can_Never_Be_Null (T) |
| then |
| Error_Msg_NE |
| ("`NOT NULL` not allowed (& already excludes null)", N, T); |
| end if; |
| end; |
| end if; |
| |
| -- Set the Ekind of the entity, unless it has been set already, as is |
| -- the case for the iteration object over a container with no variable |
| -- indexing. In that case it's been marked as a constant, and we do not |
| -- want to change it to a variable. |
| |
| if Ekind (Id) /= E_Constant then |
| Mutate_Ekind (Id, E_Variable); |
| end if; |
| |
| Reinit_Object_Size_Align (Id); |
| |
| -- If N comes from source then check that the original node is an |
| -- object reference since there may have been several rewritting and |
| -- folding. Do not do this for N_Function_Call or N_Explicit_Dereference |
| -- which might correspond to rewrites of e.g. N_Selected_Component |
| -- (for example Object.Method rewriting). |
| -- If N does not come from source then assume the tree is properly |
| -- formed and accept any object reference. In such cases we do support |
| -- more cases of renamings anyway, so the actual check on which renaming |
| -- is valid is better left to the code generator as a last sanity |
| -- check. |
| |
| if Comes_From_Source (N) then |
| if Nkind (Nam) in N_Function_Call | N_Explicit_Dereference then |
| Is_Object_Ref := Is_Object_Reference (Nam); |
| else |
| Is_Object_Ref := Is_Object_Reference (Original_Node (Nam)); |
| end if; |
| else |
| Is_Object_Ref := True; |
| end if; |
| |
| if T = Any_Type or else Etype (Nam) = Any_Type then |
| return; |
| |
| -- Verify that the renamed entity is an object or function call |
| |
| elsif Is_Object_Ref then |
| if Comes_From_Source (N) then |
| if Is_Dependent_Component_Of_Mutable_Object (Nam) then |
| Error_Msg_N |
| ("illegal renaming of discriminant-dependent component", Nam); |
| end if; |
| |
| -- If the renaming comes from source and the renamed object is a |
| -- dereference, then mark the prefix as needing debug information, |
| -- since it might have been rewritten hence internally generated |
| -- and Debug_Renaming_Declaration will link the renaming to it. |
| |
| if Nkind (Nam) = N_Explicit_Dereference |
| and then Is_Entity_Name (Prefix (Nam)) |
| then |
| Set_Debug_Info_Needed (Entity (Prefix (Nam))); |
| end if; |
| end if; |
| |
| -- Weird but legal, equivalent to renaming a function call. Illegal |
| -- if the literal is the result of constant-folding an attribute |
| -- reference that is not a function. |
| |
| elsif Is_Entity_Name (Nam) |
| and then Ekind (Entity (Nam)) = E_Enumeration_Literal |
| and then Nkind (Original_Node (Nam)) /= N_Attribute_Reference |
| then |
| null; |
| |
| -- A named number can only be renamed without a subtype mark |
| |
| elsif Nkind (Nam) in N_Real_Literal | N_Integer_Literal |
| and then Present (Subtype_Mark (N)) |
| and then Present (Original_Entity (Nam)) |
| then |
| Error_Msg_N ("incompatible types in renaming", Nam); |
| |
| -- AI12-0383: Names that denote values can be renamed. |
| -- Ignore (accept) N_Raise_xxx_Error nodes in this context. |
| |
| elsif No_Raise_xxx_Error (Nam) = OK then |
| Error_Msg_Ada_2022_Feature ("value in renaming", Sloc (Nam)); |
| end if; |
| |
| Set_Etype (Id, T2); |
| |
| if not Is_Variable (Nam) then |
| Mutate_Ekind (Id, E_Constant); |
| Set_Never_Set_In_Source (Id, True); |
| Set_Is_True_Constant (Id, True); |
| end if; |
| |
| -- The entity of the renaming declaration needs to reflect whether the |
| -- renamed object is atomic, independent, volatile or VFA. These flags |
| -- are set on the renamed object in the RM legality sense. |
| |
| Set_Is_Atomic (Id, Is_Atomic_Object (Nam)); |
| Set_Is_Independent (Id, Is_Independent_Object (Nam)); |
| Set_Is_Volatile (Id, Is_Volatile_Object_Ref (Nam)); |
| Set_Is_Volatile_Full_Access |
| (Id, Is_Volatile_Full_Access_Object_Ref (Nam)); |
| |
| -- Treat as volatile if we just set the Volatile flag |
| |
| if Is_Volatile (Id) |
| |
| -- Or if we are renaming an entity which was marked this way |
| |
| -- Are there more cases, e.g. X(J) where X is Treat_As_Volatile ??? |
| |
| or else (Is_Entity_Name (Nam) |
| and then Treat_As_Volatile (Entity (Nam))) |
| then |
| Set_Treat_As_Volatile (Id, True); |
| end if; |
| |
| -- Now make the link to the renamed object |
| |
| Set_Renamed_Object (Id, Nam); |
| |
| -- Implementation-defined aspect specifications can appear in a renaming |
| -- declaration, but not language-defined ones. The call to procedure |
| -- Analyze_Aspect_Specifications will take care of this error check. |
| |
| if Has_Aspects (N) then |
| Analyze_Aspect_Specifications (N, Id); |
| end if; |
| |
| -- Deal with dimensions |
| |
| Analyze_Dimension (N); |
| end Analyze_Object_Renaming; |
| |
| ------------------------------ |
| -- Analyze_Package_Renaming -- |
| ------------------------------ |
| |
| procedure Analyze_Package_Renaming (N : Node_Id) is |
| New_P : constant Entity_Id := Defining_Entity (N); |
| Old_P : Entity_Id; |
| Spec : Node_Id; |
| |
| begin |
| if Name (N) = Error then |
| return; |
| end if; |
| |
| -- Check for Text_IO special units (we may be renaming a Text_IO child), |
| -- but make sure not to catch renamings generated for package instances |
| -- that have nothing to do with them but are nevertheless homonyms. |
| |
| if Is_Entity_Name (Name (N)) |
| and then Present (Entity (Name (N))) |
| and then Is_Generic_Instance (Entity (Name (N))) |
| then |
| null; |
| else |
| Check_Text_IO_Special_Unit (Name (N)); |
| end if; |
| |
| if Current_Scope /= Standard_Standard then |
| Set_Is_Pure (New_P, Is_Pure (Current_Scope)); |
| end if; |
| |
| Enter_Name (New_P); |
| Analyze (Name (N)); |
| |
| if Is_Entity_Name (Name (N)) then |
| Old_P := Entity (Name (N)); |
| else |
| Old_P := Any_Id; |
| end if; |
| |
| if Etype (Old_P) = Any_Type then |
| Error_Msg_N ("expect package name in renaming", Name (N)); |
| |
| elsif Ekind (Old_P) /= E_Package |
| and then not (Ekind (Old_P) = E_Generic_Package |
| and then In_Open_Scopes (Old_P)) |
| then |
| if Ekind (Old_P) = E_Generic_Package then |
| Error_Msg_N |
| ("generic package cannot be renamed as a package", Name (N)); |
| else |
| Error_Msg_Sloc := Sloc (Old_P); |
| Error_Msg_NE |
| ("expect package name in renaming, found& declared#", |
| Name (N), Old_P); |
| end if; |
| |
| -- Set basic attributes to minimize cascaded errors |
| |
| Mutate_Ekind (New_P, E_Package); |
| Set_Etype (New_P, Standard_Void_Type); |
| |
| elsif Present (Renamed_Entity (Old_P)) |
| and then (From_Limited_With (Renamed_Entity (Old_P)) |
| or else Has_Limited_View (Renamed_Entity (Old_P))) |
| and then not |
| Unit_Is_Visible (Cunit (Get_Source_Unit (Renamed_Entity (Old_P)))) |
| then |
| Error_Msg_NE |
| ("renaming of limited view of package & not usable in this context" |
| & " (RM 8.5.3(3.1/2))", Name (N), Renamed_Entity (Old_P)); |
| |
| -- Set basic attributes to minimize cascaded errors |
| |
| Mutate_Ekind (New_P, E_Package); |
| Set_Etype (New_P, Standard_Void_Type); |
| |
| -- Here for OK package renaming |
| |
| else |
| -- Entities in the old package are accessible through the renaming |
| -- entity. The simplest implementation is to have both packages share |
| -- the entity list. |
| |
| Mutate_Ekind (New_P, E_Package); |
| Set_Etype (New_P, Standard_Void_Type); |
| |
| if Present (Renamed_Entity (Old_P)) then |
| Set_Renamed_Entity (New_P, Renamed_Entity (Old_P)); |
| else |
| Set_Renamed_Entity (New_P, Old_P); |
| end if; |
| |
| -- The package renaming declaration may become Ghost if it renames a |
| -- Ghost entity. |
| |
| Mark_Ghost_Renaming (N, Old_P); |
| |
| Set_Has_Completion (New_P); |
| Set_First_Entity (New_P, First_Entity (Old_P)); |
| Set_Last_Entity (New_P, Last_Entity (Old_P)); |
| Set_First_Private_Entity (New_P, First_Private_Entity (Old_P)); |
| Check_Library_Unit_Renaming (N, Old_P); |
| Generate_Reference (Old_P, Name (N)); |
| |
| -- If the renaming is in the visible part of a package, then we set |
| -- Renamed_In_Spec for the renamed package, to prevent giving |
| -- warnings about no entities referenced. Such a warning would be |
| -- overenthusiastic, since clients can see entities in the renamed |
| -- package via the visible package renaming. |
| |
| declare |
| Ent : constant Entity_Id := Cunit_Entity (Current_Sem_Unit); |
| begin |
| if Ekind (Ent) = E_Package |
| and then not In_Private_Part (Ent) |
| and then In_Extended_Main_Source_Unit (N) |
| and then Ekind (Old_P) = E_Package |
| then |
| Set_Renamed_In_Spec (Old_P); |
| end if; |
| end; |
| |
| -- If this is the renaming declaration of a package instantiation |
| -- within itself, it is the declaration that ends the list of actuals |
| -- for the instantiation. At this point, the subtypes that rename |
| -- the actuals are flagged as generic, to avoid spurious ambiguities |
| -- if the actuals for two distinct formals happen to coincide. If |
| -- the actual is a private type, the subtype has a private completion |
| -- that is flagged in the same fashion. |
| |
| -- Resolution is identical to what is was in the original generic. |
| -- On exit from the generic instance, these are turned into regular |
| -- subtypes again, so they are compatible with types in their class. |
| |
| if not Is_Generic_Instance (Old_P) then |
| return; |
| else |
| Spec := Specification (Unit_Declaration_Node (Old_P)); |
| end if; |
| |
| if Nkind (Spec) = N_Package_Specification |
| and then Present (Generic_Parent (Spec)) |
| and then Old_P = Current_Scope |
| and then Chars (New_P) = Chars (Generic_Parent (Spec)) |
| then |
| declare |
| E : Entity_Id; |
| |
| begin |
| E := First_Entity (Old_P); |
| while Present (E) and then E /= New_P loop |
| if Is_Type (E) |
| and then Nkind (Parent (E)) = N_Subtype_Declaration |
| then |
| Set_Is_Generic_Actual_Type (E); |
| |
| if Is_Private_Type (E) |
| and then Present (Full_View (E)) |
| then |
| Set_Is_Generic_Actual_Type (Full_View (E)); |
| end if; |
| end if; |
| |
| Next_Entity (E); |
| end loop; |
| end; |
| end if; |
| end if; |
| |
| -- Implementation-defined aspect specifications can appear in a renaming |
| -- declaration, but not language-defined ones. The call to procedure |
| -- Analyze_Aspect_Specifications will take care of this error check. |
| |
| if Has_Aspects (N) then |
| Analyze_Aspect_Specifications (N, New_P); |
| end if; |
| end Analyze_Package_Renaming; |
| |
| ------------------------------- |
| -- Analyze_Renamed_Character -- |
| ------------------------------- |
| |
| procedure Analyze_Renamed_Character |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean) |
| is |
| C : constant Node_Id := Name (N); |
| |
| begin |
| if Ekind (New_S) = E_Function then |
| Resolve (C, Etype (New_S)); |
| |
| if Is_Body then |
| Check_Frozen_Renaming (N, New_S); |
| end if; |
| |
| else |
| Error_Msg_N ("character literal can only be renamed as function", N); |
| end if; |
| end Analyze_Renamed_Character; |
| |
| --------------------------------- |
| -- Analyze_Renamed_Dereference -- |
| --------------------------------- |
| |
| procedure Analyze_Renamed_Dereference |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean) |
| is |
| Nam : constant Node_Id := Name (N); |
| P : constant Node_Id := Prefix (Nam); |
| Typ : Entity_Id; |
| Ind : Interp_Index; |
| It : Interp; |
| |
| begin |
| if not Is_Overloaded (P) then |
| if Ekind (Etype (Nam)) /= E_Subprogram_Type |
| or else not Type_Conformant (Etype (Nam), New_S) |
| then |
| Error_Msg_N ("designated type does not match specification", P); |
| else |
| Resolve (P); |
| end if; |
| |
| return; |
| |
| else |
| Typ := Any_Type; |
| Get_First_Interp (Nam, Ind, It); |
| |
| while Present (It.Nam) loop |
| |
| if Ekind (It.Nam) = E_Subprogram_Type |
| and then Type_Conformant (It.Nam, New_S) |
| then |
| if Typ /= Any_Id then |
| Error_Msg_N ("ambiguous renaming", P); |
| return; |
| else |
| Typ := It.Nam; |
| end if; |
| end if; |
| |
| Get_Next_Interp (Ind, It); |
| end loop; |
| |
| if Typ = Any_Type then |
| Error_Msg_N ("designated type does not match specification", P); |
| else |
| Resolve (N, Typ); |
| |
| if Is_Body then |
| Check_Frozen_Renaming (N, New_S); |
| end if; |
| end if; |
| end if; |
| end Analyze_Renamed_Dereference; |
| |
| --------------------------- |
| -- Analyze_Renamed_Entry -- |
| --------------------------- |
| |
| procedure Analyze_Renamed_Entry |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean) |
| is |
| Nam : constant Node_Id := Name (N); |
| Sel : constant Node_Id := Selector_Name (Nam); |
| Is_Actual : constant Boolean := Present (Corresponding_Formal_Spec (N)); |
| Old_S : Entity_Id; |
| |
| begin |
| if Entity (Sel) = Any_Id then |
| |
| -- Selector is undefined on prefix. Error emitted already |
| |
| Set_Has_Completion (New_S); |
| return; |
| end if; |
| |
| -- Otherwise find renamed entity and build body of New_S as a call to it |
| |
| Old_S := Find_Renamed_Entity (N, Selector_Name (Nam), New_S); |
| |
| if Old_S = Any_Id then |
| Error_Msg_N ("no subprogram or entry matches specification", N); |
| else |
| if Is_Body then |
| Check_Subtype_Conformant (New_S, Old_S, N); |
| Generate_Reference (New_S, Defining_Entity (N), 'b'); |
| Style.Check_Identifier (Defining_Entity (N), New_S); |
| |
| else |
| -- Only mode conformance required for a renaming_as_declaration |
| |
| Check_Mode_Conformant (New_S, Old_S, N); |
| end if; |
| |
| Inherit_Renamed_Profile (New_S, Old_S); |
| |
| -- The prefix can be an arbitrary expression that yields a task or |
| -- protected object, so it must be resolved. |
| |
| if Is_Access_Type (Etype (Prefix (Nam))) then |
| Insert_Explicit_Dereference (Prefix (Nam)); |
| end if; |
| Resolve (Prefix (Nam), Scope (Old_S)); |
| end if; |
| |
| Set_Convention (New_S, Convention (Old_S)); |
| Set_Has_Completion (New_S, Inside_A_Generic); |
| |
| -- AI05-0225: If the renamed entity is a procedure or entry of a |
| -- protected object, the target object must be a variable. |
| |
| if Is_Protected_Type (Scope (Old_S)) |
| and then Ekind (New_S) = E_Procedure |
| and then not Is_Variable (Prefix (Nam)) |
| then |
| if Is_Actual then |
| Error_Msg_N |
| ("target object of protected operation used as actual for " |
| & "formal procedure must be a variable", Nam); |
| else |
| Error_Msg_N |
| ("target object of protected operation renamed as procedure, " |
| & "must be a variable", Nam); |
| end if; |
| end if; |
| |
| if Is_Body then |
| Check_Frozen_Renaming (N, New_S); |
| end if; |
| end Analyze_Renamed_Entry; |
| |
| ----------------------------------- |
| -- Analyze_Renamed_Family_Member -- |
| ----------------------------------- |
| |
| procedure Analyze_Renamed_Family_Member |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean) |
| is |
| Nam : constant Node_Id := Name (N); |
| P : constant Node_Id := Prefix (Nam); |
| Old_S : Entity_Id; |
| |
| begin |
| if (Is_Entity_Name (P) and then Ekind (Entity (P)) = E_Entry_Family) |
| or else (Nkind (P) = N_Selected_Component |
| and then Ekind (Entity (Selector_Name (P))) = E_Entry_Family) |
| then |
| if Is_Entity_Name (P) then |
| Old_S := Entity (P); |
| else |
| Old_S := Entity (Selector_Name (P)); |
| end if; |
| |
| if not Entity_Matches_Spec (Old_S, New_S) then |
| Error_Msg_N ("entry family does not match specification", N); |
| |
| elsif Is_Body then |
| Check_Subtype_Conformant (New_S, Old_S, N); |
| Generate_Reference (New_S, Defining_Entity (N), 'b'); |
| Style.Check_Identifier (Defining_Entity (N), New_S); |
| end if; |
| |
| else |
| Error_Msg_N ("no entry family matches specification", N); |
| end if; |
| |
| Set_Has_Completion (New_S, Inside_A_Generic); |
| |
| if Is_Body then |
| Check_Frozen_Renaming (N, New_S); |
| end if; |
| end Analyze_Renamed_Family_Member; |
| |
| ----------------------------------------- |
| -- Analyze_Renamed_Primitive_Operation -- |
| ----------------------------------------- |
| |
| procedure Analyze_Renamed_Primitive_Operation |
| (N : Node_Id; |
| New_S : Entity_Id; |
| Is_Body : Boolean) |
| is |
| Old_S : Entity_Id; |
| Nam : Entity_Id; |
| |
| function Conforms |
| (Subp : Entity_Id; |
| Ctyp : Conformance_Type) return Boolean; |
| -- Verify that the signatures of the renamed entity and the new entity |
| -- match. The first formal of the renamed entity is skipped because it |
| -- is the target object in any subsequent call. |
| |
| -------------- |
| -- Conforms -- |
| -------------- |
| |
| function Conforms |
| (Subp : Entity_Id; |
| Ctyp : Conformance_Type) return Boolean |
| is |
| Old_F : Entity_Id; |
| New_F : Entity_Id; |
| |
| begin |
| if Ekind (Subp) /= Ekind (New_S) then |
| return False; |
| end if; |
| |
| Old_F := Next_Formal (First_Formal (Subp)); |
| New_F := First_Formal (New_S); |
| while Present (Old_F) and then Present (New_F) loop |
| if not Conforming_Types (Etype (Old_F), Etype (New_F), Ctyp) then |
| return False; |
| end if; |
| |
| if Ctyp >= Mode_Conformant |
| and then Ekind (Old_F) /= Ekind (New_F) |
| then |
| return False; |
| end if; |
| |
| Next_Formal (New_F); |
| Next_Formal (Old_F); |
| end loop; |
| |
| return True; |
| end Conforms; |
| |
| -- Start of processing for Analyze_Renamed_Primitive_Operation |
| |
| begin |
| if not Is_Overloaded (Selector_Name (Name (N))) then |
| Old_S := Entity (Selector_Name (Name (N))); |
| |
| if not Conforms (Old_S, Type_Conformant) then |
| Old_S := Any_Id; |
| end if; |
| |
| else |
| -- Find the operation that matches the given signature |
| |
| declare |
| It : Interp; |
| Ind : Interp_Index; |
| |
| begin |
| Old_S := Any_Id; |
| Get_First_Interp (Selector_Name (Name (N)), Ind, It); |
| |
| while Present (It.Nam) loop |
| if Conforms (It.Nam, Type_Conformant) then |
| Old_S := It.Nam; |
| end if; |
| |
| Get_Next_Interp (Ind, It); |
| end loop; |
| end; |
| end if; |
| |
| if Old_S = Any_Id then |
| Error_Msg_N ("no subprogram or entry matches specification", N); |
| |
| else |
| if Is_Body then |
| if not Conforms (Old_S, Subtype_Conformant) then |
| Error_Msg_N ("subtype conformance error in renaming", N); |
| end if; |
| |
| Generate_Reference (New_S, Defining_Entity (N), 'b'); |
| Style.Check_Identifier (Defining_Entity (N), New_S); |
| |
| else |
| -- Only mode conformance required for a renaming_as_declaration |
| |
| if not Conforms (Old_S, Mode_Conformant) then |
| Error_Msg_N ("mode conformance error in renaming", N); |
| end if; |
| |
| -- AI12-0204: The prefix of a prefixed view that is renamed or |
| -- passed as a formal subprogram must be renamable as an object. |
| |
| Nam := Prefix (Name (N)); |
| |
| if Is_Object_Reference (Nam) then |
| if Is_Dependent_Component_Of_Mutable_Object (Nam) then |
| Error_Msg_N |
| ("illegal renaming of discriminant-dependent component", |
| Nam); |
| end if; |
| else |
| Error_Msg_N ("expect object name in renaming", Nam); |
| end if; |
| |
| -- Enforce the rule given in (RM 6.3.1 (10.1/2)): a prefixed |
| -- view of a subprogram is intrinsic, because the compiler has |
| -- to generate a wrapper for any call to it. If the name in a |
| -- subprogram renaming is a prefixed view, the entity is thus |
| -- intrinsic, and 'Access cannot be applied to it. |
| |
| Set_Convention (New_S, Convention_Intrinsic); |
| end if; |
| |
| -- Inherit_Renamed_Profile (New_S, Old_S); |
| |
| -- The prefix can be an arbitrary expression that yields an |
| -- object, so it must be resolved. |
| |
| Resolve (Prefix (Name (N))); |
| end if; |
| end Analyze_Renamed_Primitive_Operation; |
| |
| --------------------------------- |
| -- Analyze_Subprogram_Renaming -- |
| --------------------------------- |
| |
| procedure Analyze_Subprogram_Renaming (N : Node_Id) is |
| Formal_Spec : constant Entity_Id := Corresponding_Formal_Spec (N); |
| Is_Actual : constant Boolean := Present (Formal_Spec); |
| Nam : constant Node_Id := Name (N); |
| Save_AV : constant Ada_Version_Type := Ada_Version; |
| Save_AVP : constant Node_Id := Ada_Version_Pragma; |
| Save_AV_Exp : constant Ada_Version_Type := Ada_Version_Explicit; |
| Spec : constant Node_Id := Specification (N); |
| |
| Old_S : Entity_Id := Empty; |
| Rename_Spec : Entity_Id; |
| |
| procedure Check_Null_Exclusion |
| (Ren : Entity_Id; |
| Sub : Entity_Id); |
| -- Ada 2005 (AI-423): Given renaming Ren of subprogram Sub, check the |
| -- following AI rules: |
| -- |
| -- If Ren denotes a generic formal object of a generic unit G, and the |
| -- renaming (or instantiation containing the actual) occurs within the |
| -- body of G or within the body of a generic unit declared within the |
| -- declarative region of G, then the corresponding parameter of G |
| -- shall have a null_exclusion; Otherwise the subtype of the Sub's |
| -- formal parameter shall exclude null. |
| -- |
| -- Similarly for its return profile. |
| |
| procedure Check_SPARK_Primitive_Operation (Subp_Id : Entity_Id); |
| -- Ensure that a SPARK renaming denoted by its entity Subp_Id does not |
| -- declare a primitive operation of a tagged type (SPARK RM 6.1.1(3)). |
| |
| procedure Freeze_Actual_Profile; |
| -- In Ada 2012, enforce the freezing rule concerning formal incomplete |
| -- types: a callable entity freezes its profile, unless it has an |
| -- incomplete untagged formal (RM 13.14(10.2/3)). |
| |
| function Has_Class_Wide_Actual return Boolean; |
| -- Ada 2012 (AI05-071, AI05-0131) and Ada 2022 (AI12-0165): True if N is |
| -- the renaming for a defaulted formal subprogram where the actual for |
| -- the controlling formal type is class-wide. |
| |
| procedure Handle_Instance_With_Class_Wide_Type |
| (Inst_Node : Node_Id; |
| Ren_Id : Entity_Id; |
| Wrapped_Prim : out Entity_Id; |
| Wrap_Id : out Entity_Id); |
| -- Ada 2012 (AI05-0071), Ada 2022 (AI12-0165): when the actual type |
| -- of an instantiation is a class-wide type T'Class we may need to |
| -- wrap a primitive operation of T; this routine looks for a suitable |
| -- primitive to be wrapped and (if the wrapper is required) returns the |
| -- Id of the wrapped primitive and the Id of the built wrapper. Ren_Id |
| -- is the defining entity for the renamed subprogram specification. |
| |
| function Original_Subprogram (Subp : Entity_Id) return Entity_Id; |
| -- Find renamed entity when the declaration is a renaming_as_body and |
| -- the renamed entity may itself be a renaming_as_body. Used to enforce |
| -- rule that a renaming_as_body is illegal if the declaration occurs |
| -- before the subprogram it completes is frozen, and renaming indirectly |
| -- renames the subprogram itself.(Defect Report 8652/0027). |
| |
| -------------------------- |
| -- Check_Null_Exclusion -- |
| -------------------------- |
| |
| procedure Check_Null_Exclusion |
| (Ren : Entity_Id; |
| Sub : Entity_Id) |
| is |
| Ren_Formal : Entity_Id; |
| Sub_Formal : Entity_Id; |
| |
| function Null_Exclusion_Mismatch |
| (Renaming : Entity_Id; Renamed : Entity_Id) return Boolean; |
| -- Return True if there is a null exclusion mismatch between |
| -- Renaming and Renamed, False otherwise. |
| |
| ----------------------------- |
| -- Null_Exclusion_Mismatch -- |
| ----------------------------- |
| |
| function Null_Exclusion_Mismatch |
| (Renaming : Entity_Id; Renamed : Entity_Id) return Boolean is |
| begin |
| return Has_Null_Exclusion (Parent (Renaming)) |
| and then |
| not (Has_Null_Exclusion (Parent (Renamed)) |
| or else (Can_Never_Be_Null (Etype (Renamed)) |
| and then not |
| (Is_Formal_Subprogram (Sub) |
| and then In_Generic_Body (Current_Scope)))); |
| end Null_Exclusion_Mismatch; |
| |
| begin |
| -- Parameter check |
| |
| Ren_Formal := First_Formal (Ren); |
| Sub_Formal := First_Formal (Sub); |
| while Present (Ren_Formal) and then Present (Sub_Formal) loop |
| if Null_Exclusion_Mismatch (Ren_Formal, Sub_Formal) then |
| Error_Msg_Sloc := Sloc (Sub_Formal); |
| Error_Msg_NE |
| ("`NOT NULL` required for parameter &#", |
| Ren_Formal, Sub_Formal); |
| end if; |
| |
| Next_Formal (Ren_Formal); |
| Next_Formal (Sub_Formal); |
| end loop; |
| |
| -- Return profile check |
| |
| if Nkind (Parent (Ren)) = N_Function_Specification |
| and then Nkind (Parent (Sub)) = N_Function_Specification |
| and then Null_Exclusion_Mismatch (Ren, Sub) |
| then |
| Error_Msg_Sloc := Sloc (Sub); |
| Error_Msg_N ("return must specify `NOT NULL`#", Ren); |
| end if; |
| end Check_Null_Exclusion; |
| |
| ------------------------------------- |
| -- Check_SPARK_Primitive_Operation -- |
| ------------------------------------- |
| |
| procedure Check_SPARK_Primitive_Operation (Subp_Id : Entity_Id) is |
| Prag : constant Node_Id := SPARK_Pragma (Subp_Id); |
| Typ : Entity_Id; |
| |
| begin |
| -- Nothing to do when the subprogram is not subject to SPARK_Mode On |
| -- because this check applies to SPARK code only. |
| |
| if not (Present (Prag) |
| and then Get_SPARK_Mode_From_Annotation (Prag) = On) |
| then |
| return; |
| |
| -- Nothing to do when the subprogram is not a primitive operation |
| |
| elsif not Is_Primitive (Subp_Id) then |
| return; |
| end if; |
| |
| Typ := Find_Dispatching_Type (Subp_Id); |
| |
| -- Nothing to do when the subprogram is a primitive operation of an |
| -- untagged type. |
| |
| if No (Typ) then |
| return; |
| end if; |
| |
| -- At this point a renaming declaration introduces a new primitive |
| -- operation for a tagged type. |
| |
| Error_Msg_Node_2 := Typ; |
| Error_Msg_NE |
| ("subprogram renaming & cannot declare primitive for type & " |
| & "(SPARK RM 6.1.1(3))", N, Subp_Id); |
| end Check_SPARK_Primitive_Operation; |
| |
| --------------------------- |
| -- Freeze_Actual_Profile -- |
| --------------------------- |
| |
| procedure Freeze_Actual_Profile is |
| F : Entity_Id; |
| Has_Untagged_Inc : Boolean; |
| Instantiation_Node : constant Node_Id := Parent (N); |
| |
| begin |
| if Ada_Version >= Ada_2012 then |
| F := First_Formal (Formal_Spec); |
| Has_Untagged_Inc := False; |
| while Present (F) loop |
| if Ekind (Etype (F)) = E_Incomplete_Type |
| and then not Is_Tagged_Type (Etype (F)) |
| then |
| Has_Untagged_Inc := True; |
| exit; |
| end if; |
| |
| Next_Formal (F); |
| end loop; |
| |
| if Ekind (Formal_Spec) = E_Function |
| and then not Is_Tagged_Type (Etype (Formal_Spec)) |
| then |
| Has_Untagged_Inc := True; |
| end if; |
| |
| if not Has_Untagged_Inc then |
| F := First_Formal (Old_S); |
| while Present (F) loop |
| Freeze_Before (Instantiation_Node, Etype (F)); |
| |
| if Is_Incomplete_Or_Private_Type (Etype (F)) |
| and then No (Underlying_Type (Etype (F))) |
| then |
| -- Exclude generic types, or types derived from them. |
| -- They will be frozen in the enclosing instance. |
| |
| if Is_Generic_Type (Etype (F)) |
| or else Is_Generic_Type (Root_Type (Etype (F))) |
| then |
| null; |
| |
| -- A limited view of a type declared elsewhere needs no |
| -- freezing actions. |
| |
| elsif From_Limited_With (Etype (F)) then |
| null; |
| |
| else |
| Error_Msg_NE |
| ("type& must be frozen before this point", |
| Instantiation_Node, Etype (F)); |
| end if; |
| end if; |
| |
| Next_Formal (F); |
| end loop; |
| end if; |
| end if; |
| end Freeze_Actual_Profile; |
| |
| --------------------------- |
| -- Has_Class_Wide_Actual -- |
| --------------------------- |
| |
| function Has_Class_Wide_Actual return Boolean is |
| Formal : Entity_Id; |
| Formal_Typ : Entity_Id; |
| |
| begin |
| if Is_Actual then |
| Formal := First_Formal (Formal_Spec); |
| while Present (Formal) loop |
| Formal_Typ := Etype (Formal); |
| |
| if Has_Unknown_Discriminants (Formal_Typ) |
| and then not Is_Class_Wide_Type (Formal_Typ) |
| and then Is_Class_Wide_Type (Get_Instance_Of (Formal_Typ)) |
| then |
| return True; |
| end if; |
| |
| Next_Formal (Formal); |
| end loop; |
| end if; |
| |
| return False; |
| end Has_Class_Wide_Actual; |
| |
| ------------------------------------------ |
| -- Handle_Instance_With_Class_Wide_Type -- |
| ------------------------------------------ |
| |
| procedure Handle_Instance_With_Class_Wide_Type |
| (Inst_Node : Node_Id; |
| Ren_Id : Entity_Id; |
| Wrapped_Prim : out Entity_Id; |
| Wrap_Id : out Entity_Id) |
| is |
| procedure Build_Class_Wide_Wrapper |
| (Ren_Id : Entity_Id; |
| Prim_Op : Entity_Id; |
| Wrap_Id : out Entity_Id); |
| -- Build a wrapper for the renaming Ren_Id of subprogram Prim_Op. |
| |
| procedure Find_Suitable_Candidate |
| (Prim_Op : out Entity_Id; |
| Is_CW_Prim : out Boolean); |
| -- Look for a suitable primitive to be wrapped (Prim_Op); Is_CW_Prim |
| -- indicates that the found candidate is a class-wide primitive (to |
| -- help the caller decide if the wrapper is required). |
| |
| ------------------------------ |
| -- Build_Class_Wide_Wrapper -- |
| ------------------------------ |
| |
| procedure Build_Class_Wide_Wrapper |
| (Ren_Id : Entity_Id; |
| Prim_Op : Entity_Id; |
| Wrap_Id : out Entity_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| |
| function Build_Call |
| (Subp_Id : Entity_Id; |
| Params : List_Id) return Node_Id; |
| -- Create a dispatching call to invoke routine Subp_Id with |
| -- actuals built from the parameter specifications of list Params. |
| |
| function Build_Expr_Fun_Call |
| (Subp_Id : Entity_Id; |
| Params : List_Id) return Node_Id; |
| -- Create a dispatching call to invoke function Subp_Id with |
| -- actuals built from the parameter specifications of list Params. |
| -- Directly return the call, so that it can be used inside an |
| -- expression function. This is a requirement of GNATprove mode. |
| |
| function Build_Spec (Subp_Id : Entity_Id) return Node_Id; |
| -- Create a subprogram specification based on the subprogram |
| -- profile of Subp_Id. |
| |
| ---------------- |
| -- Build_Call -- |
| ---------------- |
| |
| function Build_Call |
| (Subp_Id : Entity_Id; |
| Params : List_Id) return Node_Id |
| is |
| Actuals : constant List_Id := New_List; |
| Call_Ref : constant Node_Id := New_Occurrence_Of (Subp_Id, Loc); |
| Formal : Node_Id; |
| |
| begin |
| -- Build the actual parameters of the call |
| |
| Formal := First (Params); |
| while Present (Formal) loop |
| Append_To (Actuals, |
| Make_Identifier (Loc, |
| Chars (Defining_Identifier (Formal)))); |
| Next (Formal); |
| end loop; |
| |
| -- Generate: |
| -- return Subp_Id (Actuals); |
| |
| if Ekind (Subp_Id) in E_Function | E_Operator then |
| return |
| Make_Simple_Return_Statement (Loc, |
| Expression => |
| Make_Function_Call (Loc, |
| Name => Call_Ref, |
| Parameter_Associations => Actuals)); |
| |
| -- Generate: |
| -- Subp_Id (Actuals); |
| |
| else |
| return |
| Make_Procedure_Call_Statement (Loc, |
| Name => Call_Ref, |
| Parameter_Associations => Actuals); |
| end if; |
| end Build_Call; |
| |
| ------------------------- |
| -- Build_Expr_Fun_Call -- |
| ------------------------- |
| |
| function Build_Expr_Fun_Call |
| (Subp_Id : Entity_Id; |
| Params : List_Id) return Node_Id |
| is |
| Actuals : constant List_Id := New_List; |
| Call_Ref : constant Node_Id := New_Occurrence_Of (Subp_Id, Loc); |
| Formal : Node_Id; |
| |
| begin |
| pragma Assert (Ekind (Subp_Id) in E_Function | E_Operator); |
| |
| -- Build the actual parameters of the call |
| |
| Formal := First (Params); |
| while Present (Formal) loop |
| Append_To (Actuals, |
| Make_Identifier (Loc, |
| Chars (Defining_Identifier (Formal)))); |
| Next (Formal); |
| end loop; |
| |
| -- Generate: |
| -- Subp_Id (Actuals); |
| |
| return |
| Make_Function_Call (Loc, |
| Name => Call_Ref, |
| Parameter_Associations => Actuals); |
| end Build_Expr_Fun_Call; |
| |
| ---------------- |
| -- Build_Spec -- |
| ---------------- |
| |
| function Build_Spec (Subp_Id : Entity_Id) return Node_Id is |
| Params : constant List_Id := Copy_Parameter_List (Subp_Id); |
| Spec_Id : constant Entity_Id := |
| Make_Defining_Identifier (Loc, |
| New_External_Name (Chars (Subp_Id), 'R')); |
| |
| begin |
| if Ekind (Formal_Spec) = E_Procedure then |
| return |
| Make_Procedure_Specification (Loc, |
| Defining_Unit_Name => Spec_Id, |
| Parameter_Specifications => Params); |
| else |
| return |
| Make_Function_Specification (Loc, |
| Defining_Unit_Name => Spec_Id, |
| Parameter_Specifications => Params, |
| Result_Definition => |
| New_Copy_Tree (Result_Definition (Spec))); |
| end if; |
| end Build_Spec; |
| |
| -- Local variables |
| |
| Body_Decl : Node_Id; |
| Spec_Decl : Node_Id; |
| New_Spec : Node_Id; |
| |
| -- Start of processing for Build_Class_Wide_Wrapper |
| |
| begin |
| pragma Assert (not Error_Posted (Nam)); |
| |
| -- Step 1: Create the declaration and the body of the wrapper, |
| -- insert all the pieces into the tree. |
| |
| -- In GNATprove mode, create a function wrapper in the form of an |
| -- expression function, so that an implicit postcondition relating |
| -- the result of calling the wrapper function and the result of |
| -- the dispatching call to the wrapped function is known during |
| -- proof. |
| |
| if GNATprove_Mode |
| and then Ekind (Ren_Id) in E_Function | E_Operator |
| then |
| New_Spec := Build_Spec (Ren_Id); |
| Body_Decl := |
| Make_Expression_Function (Loc, |
| Specification => New_Spec, |
| Expression => |
| Build_Expr_Fun_Call |
| (Subp_Id => Prim_Op, |
| Params => Parameter_Specifications (New_Spec))); |
| |
| Wrap_Id := Defining_Entity (Body_Decl); |
| |
| -- Otherwise, create separate spec and body for the subprogram |
| |
| else |
| Spec_Decl := |
| Make_Subprogram_Declaration (Loc, |
| Specification => Build_Spec (Ren_Id)); |
| Insert_Before_And_Analyze (N, Spec_Decl); |
| |
| Wrap_Id := Defining_Entity (Spec_Decl); |
| |
| Body_Decl := |
| Make_Subprogram_Body (Loc, |
| Specification => Build_Spec (Ren_Id), |
| Declarations => New_List, |
| Handled_Statement_Sequence => |
| Make_Handled_Sequence_Of_Statements (Loc, |
| Statements => New_List ( |
| Build_Call |
| (Subp_Id => Prim_Op, |
| Params => |
| Parameter_Specifications |
| (Specification (Spec_Decl)))))); |
| |
| Set_Corresponding_Body (Spec_Decl, Defining_Entity (Body_Decl)); |
| end if; |
| |
| Set_Is_Class_Wide_Wrapper (Wrap_Id); |
| |
| -- If the operator carries an Eliminated pragma, indicate that |
| -- the wrapper is also to be eliminated, to prevent spurious |
| -- errors when using gnatelim on programs that include box- |
| -- defaulted initialization of equality operators. |
| |
| Set_Is_Eliminated (Wrap_Id, Is_Eliminated (Prim_Op)); |
| |
| -- In GNATprove mode, insert the body in the tree for analysis |
| |
| if GNATprove_Mode then |
| Insert_Before_And_Analyze (N, Body_Decl); |
| end if; |
| |
| -- The generated body does not freeze and must be analyzed when |
| -- the class-wide wrapper is frozen. The body is only needed if |
| -- expansion is enabled. |
| |
| if Expander_Active then |
| Append_Freeze_Action (Wrap_Id, Body_Decl); |
| end if; |
| |
| -- Step 2: The subprogram renaming aliases the wrapper |
| |
| Rewrite (Name (N), New_Occurrence_Of (Wrap_Id, Loc)); |
| end Build_Class_Wide_Wrapper; |
| |
| ----------------------------- |
| -- Find_Suitable_Candidate -- |
| ----------------------------- |
| |
| procedure Find_Suitable_Candidate |
| (Prim_Op : out Entity_Id; |
| Is_CW_Prim : out Boolean) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| |
| function Find_Primitive (Typ : Entity_Id) return Entity_Id; |
| -- Find a primitive subprogram of type Typ which matches the |
| -- profile of the renaming declaration. |
| |
| procedure Interpretation_Error (Subp_Id : Entity_Id); |
| -- Emit a continuation error message suggesting subprogram Subp_Id |
| -- as a possible interpretation. |
| |
| function Is_Intrinsic_Equality |
| (Subp_Id : Entity_Id) return Boolean; |
| -- Determine whether subprogram Subp_Id denotes the intrinsic "=" |
| -- operator. |
| |
| function Is_Suitable_Candidate |
| (Subp_Id : Entity_Id) return Boolean; |
| -- Determine whether subprogram Subp_Id is a suitable candidate |
| -- for the role of a wrapped subprogram. |
| |
| -------------------- |
| -- Find_Primitive -- |
| -------------------- |
| |
| function Find_Primitive (Typ : Entity_Id) return Entity_Id is |
| procedure Replace_Parameter_Types (Spec : Node_Id); |
| -- Given a specification Spec, replace all class-wide parameter |
| -- types with reference to type Typ. |
| |
| ----------------------------- |
| -- Replace_Parameter_Types -- |
| ----------------------------- |
| |
| procedure Replace_Parameter_Types (Spec : Node_Id) is |
| Formal : Node_Id; |
| Formal_Id : Entity_Id; |
| Formal_Typ : Node_Id; |
| |
| begin |
| Formal := First (Parameter_Specifications (Spec)); |
| while Present (Formal) loop |
| Formal_Id := Defining_Identifier (Formal); |
| Formal_Typ := Parameter_Type (Formal); |
| |
| -- Create a new entity for each class-wide formal to |
| -- prevent aliasing with the original renaming. Replace |
| -- the type of such a parameter with the candidate type. |
| |
| if Nkind (Formal_Typ) = N_Identifier |
| and then Is_Class_Wide_Type (Etype (Formal_Typ)) |
| then |
| Set_Defining_Identifier (Formal, |
| Make_Defining_Identifier (Loc, Chars (Formal_Id))); |
| |
| Set_Parameter_Type (Formal, |
| New_Occurrence_Of (Typ, Loc)); |
| end if; |
| |
| Next (Formal); |
| end loop; |
| end Replace_Parameter_Types; |
| |
| -- Local variables |
| |
| Alt_Ren : constant Node_Id := New_Copy_Tree (N); |
| Alt_Nam : constant Node_Id := Name (Alt_Ren); |
| Alt_Spec : constant Node_Id := Specification (Alt_Ren); |
| Subp_Id : Entity_Id; |
| |
| -- Start of processing for Find_Primitive |
| |
| begin |
| -- Each attempt to find a suitable primitive of a particular |
| -- type operates on its own copy of the original renaming. |
| -- As a result the original renaming is kept decoration and |
| -- side-effect free. |
| |
| -- Inherit the overloaded status of the renamed subprogram name |
| |
| if Is_Overloaded (Nam) then |
| Set_Is_Overloaded (Alt_Nam); |
| Save_Interps (Nam, Alt_Nam); |
| end if; |
| |
| -- The copied renaming is hidden from visibility to prevent the |
| -- pollution of the enclosing context. |
| |
| Set_Defining_Unit_Name (Alt_Spec, Make_Temporary (Loc, 'R')); |
| |
| -- The types of all class-wide parameters must be changed to |
| -- the candidate type. |
| |
| Replace_Parameter_Types (Alt_Spec); |
| |
| -- Try to find a suitable primitive that matches the altered |
| -- profile of the renaming specification. |
| |
| Subp_Id := |
| Find_Renamed_Entity |
| (N => Alt_Ren, |
| Nam => Name (Alt_Ren), |
| New_S => Analyze_Subprogram_Specification (Alt_Spec), |
| Is_Actual => Is_Actual); |
| |
| -- Do not return Any_Id if the resolution of the altered |
| -- profile failed as this complicates further checks on |
| -- the caller side; return Empty instead. |
| |
| if Subp_Id = Any_Id then |
| return Empty; |
| else |
| return Subp_Id; |
| end if; |
| end Find_Primitive; |
| |
| -------------------------- |
| -- Interpretation_Error -- |
| -------------------------- |
| |
| procedure Interpretation_Error (Subp_Id : Entity_Id) is |
| begin |
| Error_Msg_Sloc := Sloc (Subp_Id); |
| |
| if Is_Internal (Subp_Id) then |
| Error_Msg_NE |
| ("\\possible interpretation: predefined & #", |
| Spec, Formal_Spec); |
| else |
| Error_Msg_NE |
| ("\\possible interpretation: & defined #", |
| Spec, Formal_Spec); |
| end if; |
| end Interpretation_Error; |
| |
| --------------------------- |
| -- Is_Intrinsic_Equality -- |
| --------------------------- |
| |
| function Is_Intrinsic_Equality (Subp_Id : Entity_Id) return Boolean |
| is |
| begin |
| return |
| Ekind (Subp_Id) = E_Operator |
| and then Chars (Subp_Id) = Name_Op_Eq |
| and then Is_Intrinsic_Subprogram (Subp_Id); |
| end Is_Intrinsic_Equality; |
| |
| --------------------------- |
| -- Is_Suitable_Candidate -- |
| --------------------------- |
| |
| function Is_Suitable_Candidate (Subp_Id : Entity_Id) return Boolean |
| is |
| begin |
| if No (Subp_Id) then |
| return False; |
| |
| -- An intrinsic subprogram is never a good candidate. This |
| -- is an indication of a missing primitive, either defined |
| -- directly or inherited from a parent tagged type. |
| |
| elsif Is_Intrinsic_Subprogram (Subp_Id) then |
| return False; |
| |
| else |
| return True; |
| end if; |
| end Is_Suitable_Candidate; |
| |
| -- Local variables |
| |
| Actual_Typ : Entity_Id := Empty; |
| -- The actual class-wide type for Formal_Typ |
| |
| CW_Prim_OK : Boolean; |
| CW_Prim_Op : Entity_Id; |
| -- The class-wide subprogram (if available) that corresponds to |
| -- the renamed generic formal subprogram. |
| |
| Formal_Typ : Entity_Id := Empty; |
| -- The generic formal type with unknown discriminants |
| |
| Root_Prim_OK : Boolean; |
| Root_Prim_Op : Entity_Id; |
| -- The root type primitive (if available) that corresponds to the |
| -- renamed generic formal subprogram. |
| |
| Root_Typ : Entity_Id := Empty; |
| -- The root type of Actual_Typ |
| |
| Formal : Node_Id; |
| |
| -- Start of processing for Find_Suitable_Candidate |
| |
| begin |
| pragma Assert (not Error_Posted (Nam)); |
| |
| Prim_Op := Empty; |
| Is_CW_Prim := False; |
| |
| -- Analyze the renamed name, but do not resolve it. The resolution |
| -- is completed once a suitable subprogram is found. |
| |
| Analyze (Nam); |
| |
| -- When the renamed name denotes the intrinsic operator equals, |
| -- the name must be treated as overloaded. This allows for a |
| -- potential match against the root type's predefined equality |
| -- function. |
| |
| if Is_Intrinsic_Equality (Entity (Nam)) then |
| Set_Is_Overloaded (Nam); |
| Collect_Interps (Nam); |
| end if; |
| |
| -- Step 1: Find the generic formal type and its corresponding |
| -- class-wide actual type from the renamed generic formal |
| -- subprogram. |
| |
| Formal := First_Formal (Formal_Spec); |
| while Present (Formal) loop |
| if Has_Unknown_Discriminants (Etype (Formal)) |
| and then not Is_Class_Wide_Type (Etype (Formal)) |
| and then Is_Class_Wide_Type (Get_Instance_Of (Etype (Formal))) |
| then |
| Formal_Typ := Etype (Formal); |
| Actual_Typ := Base_Type (Get_Instance_Of (Formal_Typ)); |
| Root_Typ := Root_Type (Actual_Typ); |
| exit; |
| end if; |
| |
| Next_Formal (Formal); |
| end loop; |
| |
| -- The specification of the generic formal subprogram should |
| -- always contain a formal type with unknown discriminants whose |
| -- actual is a class-wide type; otherwise this indicates a failure |
| -- in function Has_Class_Wide_Actual. |
| |
| pragma Assert (Present (Formal_Typ)); |
| |
| -- Step 2: Find the proper class-wide subprogram or primitive |
| -- that corresponds to the renamed generic formal subprogram. |
| |
| CW_Prim_Op := Find_Primitive (Actual_Typ); |
| CW_Prim_OK := Is_Suitable_Candidate (CW_Prim_Op); |
| Root_Prim_Op := Find_Primitive (Root_Typ); |
| Root_Prim_OK := Is_Suitable_Candidate (Root_Prim_Op); |
| |
| -- The class-wide actual type has two subprograms that correspond |
| -- to the renamed generic formal subprogram: |
| |
| -- with procedure Prim_Op (Param : Formal_Typ); |
| |
| -- procedure Prim_Op (Param : Actual_Typ); -- may be inherited |
| -- procedure Prim_Op (Param : Actual_Typ'Class); |
| |
| -- Even though the declaration of the two subprograms is legal, a |
| -- call to either one is ambiguous and therefore illegal. |
| |
| if CW_Prim_OK and Root_Prim_OK then |
| |
| -- A user-defined primitive has precedence over a predefined |
| -- one. |
| |
| if Is_Internal (CW_Prim_Op) |
| and then not Is_Internal (Root_Prim_Op) |
| then |
| Prim_Op := Root_Prim_Op; |
| |
| elsif Is_Internal (Root_Prim_Op) |
| and then not Is_Internal (CW_Prim_Op) |
| then |
| Prim_Op := CW_Prim_Op; |
| Is_CW_Prim := True; |
| |
| elsif CW_Prim_Op = Root_Prim_Op then |
| Prim_Op := Root_Prim_Op; |
| |
| -- The two subprograms are legal but the class-wide subprogram |
| -- is a class-wide wrapper built for a previous instantiation; |
| -- the wrapper has precedence. |
| |
| elsif Present (Alias (CW_Prim_Op)) |
| and then Is_Class_Wide_Wrapper (Ultimate_Alias (CW_Prim_Op)) |
| then |
| Prim_Op := CW_Prim_Op; |
| Is_CW_Prim := True; |
| |
| -- Otherwise both candidate subprograms are user-defined and |
| -- ambiguous. |
| |
| else |
| Error_Msg_NE |
| ("ambiguous actual for generic subprogram &", |
| Spec, Formal_Spec); |
| Interpretation_Error (Root_Prim_Op); |
| Interpretation_Error (CW_Prim_Op); |
| return; |
| end if; |
| |
| elsif CW_Prim_OK and not Root_Prim_OK then |
| Prim_Op := CW_Prim_Op; |
| Is_CW_Prim := True; |
| |
| elsif not CW_Prim_OK and Root_Prim_OK then |
| Prim_Op := Root_Prim_Op; |
| |
| -- An intrinsic equality may act as a suitable candidate in the |
| -- case of a null type extension where the parent's equality |
| -- is hidden. A call to an intrinsic equality is expanded as |
| -- dispatching. |
| |
| elsif Present (Root_Prim_Op) |
| and then Is_Intrinsic_Equality (Root_Prim_Op) |
| then |
| Prim_Op := Root_Prim_Op; |
| |
| -- Otherwise there are no candidate subprograms. Let the caller |
| -- diagnose the error. |
| |
| else |
| return; |
| end if; |
| |
| -- At this point resolution has taken place and the name is no |
| -- longer overloaded. Mark the primitive as referenced. |
| |
| Set_Is_Overloaded (Name (N), False); |
| Set_Referenced (Prim_Op); |
| end Find_Suitable_Candidate; |
| |
| -- Local variables |
| |
| Is_CW_Prim : Boolean; |
| |
| -- Start of processing for Handle_Instance_With_Class_Wide_Type |
| |
| begin |
| Wrapped_Prim := Empty; |
| Wrap_Id := Empty; |
| |
| -- Ada 2012 (AI05-0071): A generic/instance scenario involving a |
| -- formal type with unknown discriminants and a generic primitive |
| -- operation of the said type with a box require special processing |
| -- when the actual is a class-wide type: |
| -- |
| -- generic |
| -- type Formal_Typ (<>) is private; |
| -- with procedure Prim_Op (Param : Formal_Typ) is <>; |
| -- package Gen is ... |
| -- |
| -- package Inst is new Gen (Actual_Typ'Class); |
| -- |
| -- In this case the general renaming mechanism used in the prologue |
| -- of an instance no longer applies: |
| -- |
| -- procedure Prim_Op (Param : Formal_Typ) renames Prim_Op; |
| -- |
| -- The above is replaced the following wrapper/renaming combination: |
| -- |
| -- procedure Wrapper (Param : Formal_Typ) is -- wrapper |
| -- begin |
| -- Prim_Op (Param); -- primitive |
| -- end Wrapper; |
| -- |
| -- procedure Prim_Op (Param : Formal_Typ) renames Wrapper; |
| -- |
| -- This transformation applies only if there is no explicit visible |
| -- class-wide operation at the point of the instantiation. Ren_Id is |
| -- the entity of the renaming declaration. When the transformation |
| -- applies, Wrapped_Prim is the entity of the wrapped primitive. |
| |
| if Box_Present (Inst_Node) then |
| Find_Suitable_Candidate |
| (Prim_Op => Wrapped_Prim, |
| Is_CW_Prim => Is_CW_Prim); |
| |
| if Present (Wrapped_Prim) then |
| if not Is_CW_Prim then |
| Build_Class_Wide_Wrapper (Ren_Id, Wrapped_Prim, Wrap_Id); |
| |
| -- Small optimization: When the candidate is a class-wide |
| -- subprogram we don't build the wrapper; we modify the |
| -- renaming declaration to directly map the actual to the |
| -- generic formal and discard the candidate. |
| |
| else |
| Rewrite (Nam, New_Occurrence_Of (Wrapped_Prim, Sloc (N))); |
| Wrapped_Prim := Empty; |
| end if; |
| end if; |
| |
| -- Ada 2022 (AI12-0165, RM 12.6(8.5/3)): The actual subprogram for a |
| -- formal_abstract_subprogram_declaration shall be: |
| -- a) a dispatching operation of the controlling type; or |
| -- b) if the controlling type is a formal type, and the actual |
| -- type corresponding to that formal type is a specific type T, |
| -- a dispatching operation of type T; or |
| -- c) if the controlling type is a formal type, and the actual |
| -- type is a class-wide type T'Class, an implicitly declared |
| -- subprogram corresponding to a primitive operation of type T. |
| |
| elsif Nkind (Inst_Node) = N_Formal_Abstract_Subprogram_Declaration |
| and then Is_Entity_Name (Nam) |
| then |
| Find_Suitable_Candidate |
| (Prim_Op => Wrapped_Prim, |
| Is_CW_Prim => Is_CW_Prim); |
| |
| if Present (Wrapped_Prim) then |
| |
| -- Cases (a) and (b); see previous description. |
| |
| if not Is_CW_Prim then |
| Build_Class_Wide_Wrapper (Ren_Id, Wrapped_Prim, Wrap_Id); |
| |
| -- Case (c); see previous description. |
| |
| -- Implicit operations of T'Class for subtype declarations |
| -- are built by Derive_Subprogram, and their Alias attribute |
| -- references the primitive operation of T. |
| |
| elsif not Comes_From_Source (Wrapped_Prim) |
| and then Nkind (Parent (Wrapped_Prim)) = N_Subtype_Declaration |
| and then Present (Alias (Wrapped_Prim)) |
| then |
| -- We don't need to build the wrapper; we modify the |
| -- renaming declaration to directly map the actual to |
| -- the generic formal and discard the candidate. |
| |
| Rewrite (Nam, |
| New_Occurrence_Of (Alias (Wrapped_Prim), Sloc (N))); |
| Wrapped_Prim := Empty; |
| |
| -- Legality rules do not apply; discard the candidate. |
| |
| else |
| Wrapped_Prim := Empty; |
| end if; |
| end if; |
| end if; |
| end Handle_Instance_With_Class_Wide_Type; |
| |
| ------------------------- |
| -- Original_Subprogram -- |
| ------------------------- |
| |
| function Original_Subprogram (Subp : Entity_Id) return Entity_Id is |
| Orig_Decl : Node_Id; |
| Orig_Subp : Entity_Id; |
| |
| begin |
| -- First case: renamed entity is itself a renaming |
| |
| if Present (Alias (Subp)) then |
| return Alias (Subp); |
| |
| elsif Nkind (Unit_Declaration_Node (Subp)) = N_Subprogram_Declaration |
| and then Present (Corresponding_Body (Unit_Declaration_Node (Subp))) |
| then |
| -- Check if renamed entity is a renaming_as_body |
| |
| Orig_Decl := |
| Unit_Declaration_Node |
| (Corresponding_Body (Unit_Declaration_Node (Subp))); |
| |
| if Nkind (Orig_Decl) = N_Subprogram_Renaming_Declaration then |
| Orig_Subp := Entity (Name (Orig_Decl)); |
| |
| if Orig_Subp = Rename_Spec then |
| |
| -- Circularity detected |
| |
| return Orig_Subp; |
| |
| else |
| return (Original_Subprogram (Orig_Subp)); |
| end if; |
| else |
| return Subp; |
| end if; |
| else |
| return Subp; |
| end if; |
| end Original_Subprogram; |
| |
| -- Local variables |
| |
| CW_Actual : constant Boolean := Has_Class_Wide_Actual; |
| -- Ada 2012 (AI05-071, AI05-0131) and Ada 2022 (AI12-0165): True if the |
| -- renaming is for a defaulted formal subprogram when the actual for a |
| -- related formal type is class-wide. |
| |
| Inst_Node : Node_Id := Empty; |
| New_S : Entity_Id := Empty; |
| Wrapped_Prim : Entity_Id := Empty; |
| |
| -- Start of processing for Analyze_Subprogram_Renaming |
| |
| begin |
| -- We must test for the attribute renaming case before the Analyze |
| -- call because otherwise Sem_Attr will complain that the attribute |
| -- is missing an argument when it is analyzed. |
| |
| if Nkind (Nam) = N_Attribute_Reference then |
| |
| -- In the case of an abstract formal subprogram association, rewrite |
| -- an actual given by a stream or Put_Image attribute as the name of |
| -- the corresponding stream or Put_Image primitive of the type. |
| |
| -- In a generic context the stream and Put_Image operations are not |
| -- generated, and this must be treated as a normal attribute |
| -- reference, to be expanded in subsequent instantiations. |
| |
| if Is_Actual |
| and then Is_Abstract_Subprogram (Formal_Spec) |
| and then Expander_Active |
| then |
| declare |
| Prefix_Type : constant Entity_Id := Entity (Prefix (Nam)); |
| Prim : Entity_Id; |
| |
| begin |
| -- The class-wide forms of the stream and Put_Image attributes |
| -- are not primitive dispatching operations (even though they |
| -- internally dispatch). |
| |
| if Is_Class_Wide_Type (Prefix_Type) then |
| Error_Msg_N |
| ("attribute must be a primitive dispatching operation", |
| Nam); |
| return; |
| end if; |
| |
| -- Retrieve the primitive subprogram associated with the |
| -- attribute. This can only be a stream attribute, since those |
| -- are the only ones that are dispatching (and the actual for |
| -- an abstract formal subprogram must be dispatching |
| -- operation). |
| |
| case Attribute_Name (Nam) is |
| when Name_Input => |
| Prim := |
| Find_Optional_Prim_Op (Prefix_Type, TSS_Stream_Input); |
| |
| when Name_Output => |
| Prim := |
| Find_Optional_Prim_Op (Prefix_Type, TSS_Stream_Output); |
| |
| when Name_Read => |
| Prim := |
| Find_Optional_Prim_Op (Prefix_Type, TSS_Stream_Read); |
| |
| when Name_Write => |
| Prim := |
| Find_Optional_Prim_Op (Prefix_Type, TSS_Stream_Write); |
| |
| when Name_Put_Image => |
| Prim := |
| Find_Optional_Prim_Op (Prefix_Type, TSS_Put_Image); |
| |
| when others => |
| Error_Msg_N |
| ("attribute must be a primitive dispatching operation", |
| Nam); |
| return; |
| end case; |
| |
| -- If no stream operation was found, and the type is limited, |
| -- the user should have defined one. This rule does not apply |
| -- to Put_Image. |
| |
| if No (Prim) |
| and then Attribute_Name (Nam) /= Name_Put_Image |
| then |
| if Is_Limited_Type (Prefix_Type) then |
| Error_Msg_NE |
| ("stream operation not defined for type&", |
| N, Prefix_Type); |
| return; |
| |
| -- Otherwise, compiler should have generated default |
| |
| else |
| raise Program_Error; |
| end if; |
| end if; |
| |
| -- Rewrite the attribute into the name of its corresponding |
| -- primitive dispatching subprogram. We can then proceed with |
| -- the usual processing for subprogram renamings. |
| |
| declare |
| Prim_Name : constant Node_Id := |
| Make_Identifier (Sloc (Nam), |
| Chars => Chars (Prim)); |
| begin |
| Set_Entity (Prim_Name, Prim); |
| Rewrite (Nam, Prim_Name); |
| Analyze (Nam); |
| end; |
| end; |
| |
| -- Normal processing for a renaming of an attribute |
| |
| else |
| Attribute_Renaming (N); |
| return; |
| end if; |
| end if; |
| |
| -- Check whether this declaration corresponds to the instantiation of a |
| -- formal subprogram. |
| |
| -- If this is an instantiation, the corresponding actual is frozen and |
| -- error messages can be made more precise. If this is a default |
| -- subprogram, the entity is already established in the generic, and is |
| -- not retrieved by visibility. If it is a default with a box, the |
| -- candidate interpretations, if any, have been collected when building |
| -- the renaming declaration. If overloaded, the proper interpretation is |
| -- determined in Find_Renamed_Entity. If the entity is an operator, |
| -- Find_Renamed_Entity applies additional visibility checks. |
| |
| if Is_Actual then |
| Inst_Node := Unit_Declaration_Node (Formal_Spec); |
| |
| -- Ada 2012 (AI05-0071) and Ada 2022 (AI12-0165): when the actual |
| -- type is a class-wide type T'Class we may need to wrap a primitive |
| -- operation of T. Search for the wrapped primitive and (if required) |
| -- build a wrapper whose body consists of a dispatching call to the |
| -- wrapped primitive of T, with its formal parameters as the actual |
| -- parameters. |
| |
| if CW_Actual and then |
| |
| -- Ada 2012 (AI05-0071): Check whether the renaming is for a |
| -- defaulted actual subprogram with a class-wide actual. |
| |
| (Box_Present (Inst_Node) |
| |
| or else |
| |
| -- Ada 2022 (AI12-0165): Check whether the renaming is for a formal |
| -- abstract subprogram declaration with a class-wide actual. |
| |
| (Nkind (Inst_Node) = N_Formal_Abstract_Subprogram_Declaration |
| and then Is_Entity_Name (Nam))) |
| then |
| New_S := Analyze_Subprogram_Specification (Spec); |
| |
| -- Do not attempt to build the wrapper if the renaming is in error |
| |
| if not Error_Posted (Nam) then |
| Handle_Instance_With_Class_Wide_Type |
| (Inst_Node => Inst_Node, |
| Ren_Id => New_S, |
| Wrapped_Prim => Wrapped_Prim, |
| Wrap_Id => Old_S); |
| |
| -- If several candidates were found, then we reported the |
| -- ambiguity; stop processing the renaming declaration to |
| -- avoid reporting further (spurious) errors. |
| |
| if Error_Posted (Spec) then |
| return; |
| end if; |
| |
| end if; |
| end if; |
| |
| if Present (Wrapped_Prim) then |
| |
| -- When the wrapper is built, the subprogram renaming aliases |
| -- the wrapper. |
| |
| Analyze (Nam); |
| |
| pragma Assert (Old_S = Entity (Nam) |
| and then Is_Class_Wide_Wrapper (Old_S)); |
| |
| -- The subprogram renaming declaration may become Ghost if it |
| -- renames a wrapper of a Ghost entity. |
| |
| Mark_Ghost_Renaming (N, Wrapped_Prim); |
| |
| elsif Is_Entity_Name (Nam) |
| and then Present (Entity (Nam)) |
| and then not Comes_From_Source (Nam) |
| and then not Is_Overloaded (Nam) |
| then |
| Old_S := Entity (Nam); |
| |
| -- The subprogram renaming declaration may become Ghost if it |
| -- renames a Ghost entity. |
| |
| Mark_Ghost_Renaming (N, Old_S); |
| |
| New_S := Analyze_Subprogram_Specification (Spec); |
| |
| -- Operator case |
| |
| if Ekind (Old_S) = E_Operator then |
| |
| -- Box present |
| |
| if Box_Present (Inst_Node) then |
| Old_S := Find_Renamed_Entity (N, Name (N), New_S, Is_Actual); |
| |
| -- If there is an immediately visible homonym of the operator |
| -- and the declaration has a default, this is worth a warning |
| -- because the user probably did not intend to get the pre- |
| -- defined operator, visible in the generic declaration. To |
| -- find if there is an intended candidate, analyze the renaming |
| -- again in the current context. |
| |
| elsif Scope (Old_S) = Standard_Standard |
| and then Present (Default_Name (Inst_Node)) |
| then |
| declare |
| Decl : constant Node_Id := New_Copy_Tree (N); |
| Hidden : Entity_Id; |
| |
| begin |
| Set_Entity (Name (Decl), Empty); |
| Analyze (Name (Decl)); |
| Hidden := |
| Find_Renamed_Entity (Decl, Name (Decl), New_S, True); |
| |
| if Present (Hidden) |
| and then In_Open_Scopes (Scope (Hidden)) |
| and then Is_Immediately_Visible (Hidden) |
| and then Comes_From_Source (Hidden) |
| and then Hidden /= Old_S |
| then |
| Error_Msg_Sloc := Sloc (Hidden); |
| Error_Msg_N |
| ("default subprogram is resolved in the generic " |
| & "declaration (RM 12.6(17))??", N); |
| Error_Msg_NE ("\and will not use & #??", N, Hidden); |
| end if; |
| end; |
| end if; |
| end if; |
| |
| else |
| Analyze (Nam); |
| |
| -- The subprogram renaming declaration may become Ghost if it |
| -- renames a Ghost entity. |
| |
| if Is_Entity_Name (Nam) then |
| Mark_Ghost_Renaming (N, Entity (Nam)); |
| end if; |
| |
| New_S := Analyze_Subprogram_Specification (Spec); |
| end if; |
| |
| else |
| -- Renamed entity must be analyzed first, to avoid being hidden by |
| -- new name (which might be the same in a generic instance). |
| |
| Analyze (Nam); |
| |
| -- The subprogram renaming declaration may become Ghost if it renames |
| -- a Ghost entity. |
| |
| if Is_Entity_Name (Nam) then |
| Mark_Ghost_Renaming (N, Entity (Nam)); |
| end if; |
| |
| -- The renaming defines a new overloaded entity, which is analyzed |
| -- like a subprogram declaration. |
| |
| New_S := Analyze_Subprogram_Specification (Spec); |
| end if; |
| |
| if Current_Scope /= Standard_Standard then |
| Set_Is_Pure (New_S, Is_Pure (Current_Scope)); |
| end if; |
| |
| -- Set SPARK mode from current context |
| |
| Set_SPARK_Pragma (New_S, SPARK_Mode_Pragma); |
| Set_SPARK_Pragma_Inherited (New_S); |
| |
| Rename_Spec := Find_Corresponding_Spec (N); |
| |
| -- Case of Renaming_As_Body |
| |
| if Present (Rename_Spec) then |
| Check_Previous_Null_Procedure (N, Rename_Spec); |
| |
| -- Renaming declaration is the completion of the declaration of |
| -- Rename_Spec. We build an actual body for it at the freezing point. |
| |
| Set_Corresponding_Spec (N, Rename_Spec); |
| |
| -- Deal with special case of stream functions of abstract types |
| -- and interfaces. |
| |
| if Nkind (Unit_Declaration_Node (Rename_Spec)) = |
| N_Abstract_Subprogram_Declaration |
| then |
| -- Input stream functions are abstract if the object type is |
| -- abstract. Similarly, all default stream functions for an |
| -- interface type are abstract. However, these subprograms may |
| -- receive explicit declarations in representation clauses, making |
| -- the attribute subprograms usable as defaults in subsequent |
| -- type extensions. |
| -- In this case we rewrite the declaration to make the subprogram |
| -- non-abstract. We remove the previous declaration, and insert |
| -- the new one at the point of the renaming, to prevent premature |
| -- access to unfrozen types. The new declaration reuses the |
| -- specification of the previous one, and must not be analyzed. |
| |
| pragma Assert |
| (Is_Primitive (Entity (Nam)) |
| and then |
| Is_Abstract_Type (Find_Dispatching_Type (Entity (Nam)))); |
| declare |
| Old_Decl : constant Node_Id := |
| Unit_Declaration_Node (Rename_Spec); |
| New_Decl : constant Node_Id := |
| Make_Subprogram_Declaration (Sloc (N), |
| Specification => |
| Relocate_Node (Specification (Old_Decl))); |
| begin |
| Remove (Old_Decl); |
| Insert_After (N, New_Decl); |
| Set_Is_Abstract_Subprogram (Rename_Spec, False); |
| Set_Analyzed (New_Decl); |
| end; |
| end if; |
| |
| Set_Corresponding_Body (Unit_Declaration_Node (Rename_Spec), New_S); |
| |
| if Ada_Version = Ada_83 and then Comes_From_Source (N) then |
| Error_Msg_N ("(Ada 83) renaming cannot serve as a body", N); |
| end if; |
| |
| Set_Convention (New_S, Convention (Rename_Spec)); |
| Check_Fully_Conformant (New_S, Rename_Spec); |
| Set_Public_Status (New_S); |
| |
| if No_Return (Rename_Spec) |
| and then not No_Return (Entity (Nam)) |
| then |
| Error_Msg_NE |
| ("renamed subprogram & must be No_Return", N, Entity (Nam)); |
| Error_Msg_N |
| ("\since renaming subprogram is No_Return (RM 6.5.1(7/2))", N); |
| end if; |
| |
| -- The specification does not introduce new formals, but only |
| -- repeats the formals of the original subprogram declaration. |
| -- For cross-reference purposes, and for refactoring tools, we |
| -- treat the formals of the renaming declaration as body formals. |
| |
| Reference_Body_Formals (Rename_Spec, New_S); |
| |
| -- Indicate that the entity in the declaration functions like the |
| -- corresponding body, and is not a new entity. The body will be |
| -- constructed later at the freeze point, so indicate that the |
| -- completion has not been seen yet. |
| |
| Reinit_Field_To_Zero (New_S, F_Has_Out_Or_In_Out_Parameter); |
| Reinit_Field_To_Zero (New_S, F_Needs_No_Actuals, |
| Old_Ekind => (E_Function | E_Procedure => True, others => False)); |
| Mutate_Ekind (New_S, E_Subprogram_Body); |
| New_S := Rename_Spec; |
| Set_Has_Completion (Rename_Spec, False); |
| |
| -- Ada 2005: check overriding indicator |
| |
| if Present (Overridden_Operation (Rename_Spec)) then |
| if Must_Not_Override (Specification (N)) then |
| Error_Msg_NE |
| ("subprogram& overrides inherited operation", |
| N, Rename_Spec); |
| |
| elsif Style_Check |
| and then not Must_Override (Specification (N)) |
| then |
| Style.Missing_Overriding (N, Rename_Spec); |
| end if; |
| |
| elsif Must_Override (Specification (N)) |
| and then not Can_Override_Operator (Rename_Spec) |
| then |
| Error_Msg_NE ("subprogram& is not overriding", N, Rename_Spec); |
| end if; |
| |
| -- AI12-0132: a renames-as-body freezes the expression of any |
| -- expression function that it renames. |
| |
| if Is_Entity_Name (Nam) |
| and then Is_Expression_Function (Entity (Nam)) |
| and then not Inside_A_Generic |
| then |
| Freeze_Expr_Types |
| (Def_Id => Entity (Nam), |
| Typ => Etype (Entity (Nam)), |
| Expr => |
| Expression |
| (Original_Node (Unit_Declaration_Node (Entity (Nam)))), |
| N => N); |
| end if; |
| |
| -- Normal subprogram renaming (not renaming as body) |
| |
| else |
| Generate_Definition (New_S); |
| New_Overloaded_Entity (New_S); |
| |
| if not (Is_Entity_Name (Nam) |
| and then Is_Intrinsic_Subprogram (Entity (Nam))) |
| then |
| Check_Delayed_Subprogram (New_S); |
| end if; |
| |
| -- Verify that a SPARK renaming does not declare a primitive |
| -- operation of a tagged type. |
| |
| Check_SPARK_Primitive_Operation (New_S); |
| end if; |
| |
| -- There is no need for elaboration checks on the new entity, which may |
| -- be called before the next freezing point where the body will appear. |
| -- Elaboration checks refer to the real entity, not the one created by |
| -- the renaming declaration. |
| |
| Set_Kill_Elaboration_Checks (New_S, True); |
| |
| -- If we had a previous error, indicate a completion is present to stop |
| -- junk cascaded messages, but don't take any further action. |
| |
| if Etype (Nam) = Any_Type then |
| Set_Has_Completion (New_S); |
| return; |
| |
| -- Case where name has the form of a selected component |
| |
| elsif Nkind (Nam) = N_Selected_Component then |
| |
| -- A name which has the form A.B can designate an entry of task A, a |
| -- protected operation of protected object A, or finally a primitive |
| -- operation of object A. In the later case, A is an object of some |
| -- tagged type, or an access type that denotes one such. To further |
| -- distinguish these cases, note that the scope of a task entry or |
| -- protected operation is type of the prefix. |
| |
| -- The prefix could be an overloaded function call that returns both |
| -- kinds of operations. This overloading pathology is left to the |
| -- dedicated reader ??? |
| |
| declare |
| T : constant Entity_Id := Etype (Prefix (Nam)); |
| |
| begin |
| if Present (T) |
| and then |
| (Is_Tagged_Type (T) |
| or else |
| (Is_Access_Type (T) |
| and then Is_Tagged_Type (Designated_Type (T)))) |
| and then Scope (Entity (Selector_Name (Nam))) /= T |
| then |
| Analyze_Renamed_Primitive_Operation |
| (N, New_S, Present (Rename_Spec)); |
| return; |
| |
| else |
| -- Renamed entity is an entry or protected operation. For those |
| -- cases an explicit body is built (at the point of freezing of |
| -- this entity) that contains a call to the renamed entity. |
| |
| -- This is not allowed for renaming as body if the renamed |
| -- spec is already frozen (see RM 8.5.4(5) for details). |
| |
| if Present (Rename_Spec) and then Is_Frozen (Rename_Spec) then |
| Error_Msg_N |
| ("renaming-as-body cannot rename entry as subprogram", N); |
| Error_Msg_NE |
| ("\since & is already frozen (RM 8.5.4(5))", |
| N, Rename_Spec); |
| else |
| Analyze_Renamed_Entry (N, New_S, Present (Rename_Spec)); |
| end if; |
| |
| return; |
| end if; |
| end; |
| |
| -- Case where name is an explicit dereference X.all |
| |
| elsif Nkind (Nam) = N_Explicit_Dereference then |
| |
| -- Renamed entity is designated by access_to_subprogram expression. |
| -- Must build body to encapsulate call, as in the entry case. |
| |
| Analyze_Renamed_Dereference (N, New_S, Present (Rename_Spec)); |
| return; |
| |
| -- Indexed component |
| |
| elsif Nkind (Nam) = N_Indexed_Component then |
| Analyze_Renamed_Family_Member (N, New_S, Present (Rename_Spec)); |
| return; |
| |
| -- Character literal |
| |
| elsif Nkind (Nam) = N_Character_Literal then |
| Analyze_Renamed_Character (N, New_S, Present (Rename_Spec)); |
| return; |
| |
| -- Only remaining case is where we have a non-entity name, or a renaming |
| -- of some other non-overloadable entity. |
| |
| elsif not Is_Entity_Name (Nam) |
| or else not Is_Overloadable (Entity (Nam)) |
| then |
| -- Do not mention the renaming if it comes from an instance |
| |
| if not Is_Actual then |
| Error_Msg_N ("expect valid subprogram name in renaming", N); |
| else |
| Error_Msg_NE ("no visible subprogram for formal&", N, Nam); |
| end if; |
| |
| return; |
| end if; |
| |
| -- Find the renamed entity that matches the given specification. Disable |
| -- Ada_83 because there is no requirement of full conformance between |
| -- renamed entity and new entity, even though the same circuit is used. |
| |
| -- This is a bit of an odd case, which introduces a really irregular use |
| -- of Ada_Version[_Explicit]. Would be nice to find cleaner way to do |
| -- this. ??? |
| |
| Ada_Version := Ada_Version_Type'Max (Ada_Version, Ada_95); |
| Ada_Version_Pragma := Empty; |
| Ada_Version_Explicit := Ada_Version; |
| |
| if No (Old_S) then |
| Old_S := Find_Renamed_Entity (N, Name (N), New_S, Is_Actual); |
| |
| -- The visible operation may be an inherited abstract operation that |
| -- was overridden in the private part, in which case a call will |
| -- dispatch to the overriding operation. Use the overriding one in |
| -- the renaming declaration, to prevent spurious errors below. |
| |
| if Is_Overloadable (Old_S) |
| and then Is_Abstract_Subprogram (Old_S) |
| and then No (DTC_Entity (Old_S)) |
| and then Present (Alias (Old_S)) |
| and then not Is_Abstract_Subprogram (Alias (Old_S)) |
| and then Present (Overridden_Operation (Alias (Old_S))) |
| then |
| Old_S := Alias (Old_S); |
| end if; |
| |
| -- When the renamed subprogram is overloaded and used as an actual |
| -- of a generic, its entity is set to the first available homonym. |
| -- We must first disambiguate the name, then set the proper entity. |
| |
| if Is_Actual and then Is_Overloaded (Nam) then |
| Set_Entity (Nam, Old_S); |
| end if; |
| end if; |
| |
| -- Most common case: subprogram renames subprogram. No body is generated |
| -- in this case, so we must indicate the declaration is complete as is. |
| -- and inherit various attributes of the renamed subprogram. |
| |
| if No (Rename_Spec) then |
| Set_Has_Completion (New_S); |
| Set_Is_Imported (New_S, Is_Imported (Entity (Nam))); |
| Set_Is_Pure (New_S, Is_Pure (Entity (Nam))); |
| Set_Is_Preelaborated (New_S, Is_Preelaborated (Entity (Nam))); |
| |
| -- Ada 2005 (AI-423): Check the consistency of null exclusions |
| -- between a subprogram and its correct renaming. |
| |
| -- Note: the Any_Id check is a guard that prevents compiler crashes |
| -- when performing a null exclusion check between a renaming and a |
| -- renamed subprogram that has been found to be illegal. |
| |
| if Ada_Version >= Ada_2005 and then Entity (Nam) /= Any_Id then |
| Check_Null_Exclusion |
| (Ren => New_S, |
| Sub => Entity (Nam)); |
| end if; |
| |
| -- Enforce the Ada 2005 rule that the renamed entity cannot require |
| -- overriding. The flag Requires_Overriding is set very selectively |
| -- and misses some other illegal cases. The additional conditions |
| -- checked below are sufficient but not necessary ??? |
| |
| -- The rule does not apply to the renaming generated for an actual |
| -- subprogram in an instance. |
| |
| if Is_Actual then |
| null; |
| |
| -- Guard against previous errors, and omit renamings of predefined |
| -- operators. |
| |
| elsif Ekind (Old_S) not in E_Function | E_Procedure then |
| null; |
| |
| elsif Requires_Overriding (Old_S) |
| or else |
| (Is_Abstract_Subprogram (Old_S) |
| and then Present (Find_Dispatching_Type (Old_S)) |
| and then not Is_Abstract_Type (Find_Dispatching_Type (Old_S))) |
| then |
| Error_Msg_N |
| ("renamed entity cannot be subprogram that requires overriding " |
| & "(RM 8.5.4 (5.1))", N); |
| end if; |
| |
| declare |
| Prev : constant Entity_Id := Overridden_Operation (New_S); |
| begin |
| if Present (Prev) |
| and then |
| (Has_Non_Trivial_Precondition (Prev) |
| or else Has_Non_Trivial_Precondition (Old_S)) |
| then |
| Error_Msg_NE |
| ("conflicting inherited classwide preconditions in renaming " |
| & "of& (RM 6.1.1 (17)", N, Old_S); |
| end if; |
| end; |
| end if; |
| |
| if Old_S /= Any_Id then |
| if Is_Actual and then From_Default (N) then |
| |
| -- This is an implicit reference to the default actual |
| |
| Generate_Reference (Old_S, Nam, Typ => 'i', Force => True); |
| |
| else |
| Generate_Reference (Old_S, Nam); |
| end if; |
| |
| Check_Internal_Protected_Use (N, Old_S); |
| |
| -- For a renaming-as-body, require subtype conformance, but if the |
| -- declaration being completed has not been frozen, then inherit the |
| -- convention of the renamed subprogram prior to checking conformance |
| -- (unless the renaming has an explicit convention established; the |
| -- rule stated in the RM doesn't seem to address this ???). |
| |
| if Present (Rename_Spec) then |
| Generate_Reference (Rename_Spec, Defining_Entity (Spec), 'b'); |
| Style.Check_Identifier (Defining_Entity (Spec), Rename_Spec); |
| |
| if not Is_Frozen (Rename_Spec) then |
| if not Has_Convention_Pragma (Rename_Spec) then |
| Set_Convention (New_S, Convention (Old_S)); |
| end if; |
| |
| if Ekind (Old_S) /= E_Operator then |
| Check_Mode_Conformant (New_S, Old_S, Spec); |
| end if; |
| |
| if Original_Subprogram (Old_S) = Rename_Spec then |
| Error_Msg_N ("unfrozen subprogram cannot rename itself", N); |
| else |
| Check_Formal_Subprogram_Conformance (New_S, Old_S, Spec); |
| end if; |
| else |
| Check_Subtype_Conformant (New_S, Old_S, Spec); |
| end if; |
| |
| Check_Frozen_Renaming (N, Rename_Spec); |
| |
| -- Check explicitly that renamed entity is not intrinsic, because |
| -- in a generic the renamed body is not built. In this case, |
| -- the renaming_as_body is a completion. |
| |
| if Inside_A_Generic then |
| if Is_Frozen (Rename_Spec) |
| and then Is_Intrinsic_Subprogram (Old_S) |
| then |
| Error_Msg_N |
| ("subprogram in renaming_as_body cannot be intrinsic", |
| Name (N)); |
| end if; |
| |
| Set_Has_Completion (Rename_Spec); |
| end if; |
| |
| elsif Ekind (Old_S) /= E_Operator then |
| |
| -- If this a defaulted subprogram for a class-wide actual there is |
| -- no check for mode conformance, given that the signatures don't |
| -- match (the source mentions T but the actual mentions T'Class). |
| |
| if CW_Actual then |
| null; |
| |
| -- No need for a redundant error message if this is a nested |
| -- instance, unless the current instantiation (of a child unit) |
| -- is a compilation unit, which is not analyzed when the parent |
| -- generic is analyzed. |
| |
| elsif not Is_Actual |
| or else No (Enclosing_Instance) |
| or else Is_Compilation_Unit (Current_Scope) |
| then |
| Check_Mode_Conformant (New_S, Old_S); |
| end if; |
| end if; |
| |
| if No (Rename_Spec) then |
| |
| -- The parameter profile of the new entity is that of the renamed |
| -- entity: the subtypes given in the specification are irrelevant. |
| |
| Inherit_Renamed_Profile (New_S, Old_S); |
| |
| -- A call to the subprogram is transformed into a call to the |
| -- renamed entity. This is transitive if the renamed entity is |
| -- itself a renaming. |
| |
| if Present (Alias (Old_S)) then |
| Set_Alias (New_S, Alias (Old_S)); |
| else |
| Set_Alias (New_S, Old_S); |
| end if; |
| |
| -- Note that we do not set Is_Intrinsic_Subprogram if we have a |
| -- renaming as body, since the entity in this case is not an |
| -- intrinsic (it calls an intrinsic, but we have a real body for |
| -- this call, and it is in this body that the required intrinsic |
| -- processing will take place). |
| |
| -- Also, if this is a renaming of inequality, the renamed operator |
| -- is intrinsic, but what matters is the corresponding equality |
| -- operator, which may be user-defined. |
| |
| Set_Is_Intrinsic_Subprogram |
| (New_S, |
| Is_Intrinsic_Subprogram (Old_S) |
| and then |
| (Chars (Old_S) /= Name_Op_Ne |
| or else Ekind (Old_S) = E_Operator |
| or else Is_Intrinsic_Subprogram |
| (Corresponding_Equality (Old_S)))); |
| |
| if Ekind (Alias (New_S)) = E_Operator then |
| Set_Has_Delayed_Freeze (New_S, False); |
| end if; |
| |
| -- If the renaming corresponds to an association for an abstract |
| -- formal subprogram, then various attributes must be set to |
| -- indicate that the renaming is an abstract dispatching operation |
| -- with a controlling type. |
| |
| -- Skip this decoration when the renaming corresponds to an |
| -- association with class-wide wrapper (see above) because such |
| -- wrapper is neither abstract nor a dispatching operation (its |
| -- body has the dispatching call to the wrapped primitive). |
| |
| if Is_Actual |
| and then Is_Abstract_Subprogram (Formal_Spec) |
| and then No (Wrapped_Prim) |
| then |
| |
| -- Mark the renaming as abstract here, so Find_Dispatching_Type |
| -- see it as corresponding to a generic association for a |
| -- formal abstract subprogram |
| |
| Set_Is_Abstract_Subprogram (New_S); |
| |
| declare |
| New_S_Ctrl_Type : constant Entity_Id := |
| Find_Dispatching_Type (New_S); |
| Old_S_Ctrl_Type : constant Entity_Id := |
| Find_Dispatching_Type (Old_S); |
| |
| begin |
| |
| -- The actual must match the (instance of the) formal, |
| -- and must be a controlling type. |
| |
| if Old_S_Ctrl_Type /= New_S_Ctrl_Type |
| or else No (New_S_Ctrl_Type) |
| then |
| if No (New_S_Ctrl_Type) then |
| Error_Msg_N |
| ("actual must be dispatching subprogram", Nam); |
| else |
| Error_Msg_NE |
| ("actual must be dispatching subprogram for type&", |
| Nam, New_S_Ctrl_Type); |
| end if; |
| |
| else |
| Set_Is_Dispatching_Operation (New_S); |
| Check_Controlling_Formals (New_S_Ctrl_Type, New_S); |
| |
| -- If the actual in the formal subprogram is itself a |
| -- formal abstract subprogram association, there's no |
| -- dispatch table component or position to inherit. |
| |
| if Present (DTC_Entity (Old_S)) then |
| Set_DTC_Entity (New_S, DTC_Entity (Old_S)); |
| Set_DT_Position_Value (New_S, DT_Position (Old_S)); |
| end if; |
| end if; |
| end; |
| end if; |
| end if; |
| |
| if Is_Actual then |
| null; |
| |
| -- The following is illegal, because F hides whatever other F may |
| -- be around: |
| -- function F (...) renames F; |
| |
| elsif Old_S = New_S |
| or else (Nkind (Nam) /= N_Expanded_Name |
| and then Chars (Old_S) = Chars (New_S)) |
| then |
| Error_Msg_N ("subprogram cannot rename itself", N); |
| |
| -- This is illegal even if we use a selector: |
| -- function F (...) renames Pkg.F; |
| -- because F is still hidden. |
| |
| elsif Nkind (Nam) = N_Expanded_Name |
| and then Entity (Prefix (Nam)) = Current_Scope |
| and then Chars (Selector_Name (Nam)) = Chars (New_S) |
| then |
| -- This is an error, but we overlook the error and accept the |
| -- renaming if the special Overriding_Renamings mode is in effect. |
| |
| if not Overriding_Renamings then |
| Error_Msg_NE |
| ("implicit operation& is not visible (RM 8.3 (15))", |
| Nam, Old_S); |
| end if; |
| |
| -- Check whether an expanded name used for the renamed subprogram |
| -- begins with the same name as the renaming itself, and if so, |
| -- issue an error about the prefix being hidden by the renaming. |
| -- We exclude generic instances from this checking, since such |
| -- normally illegal renamings can be constructed when expanding |
| -- instantiations. |
| |
| elsif Nkind (Nam) = N_Expanded_Name and then not In_Instance then |
| declare |
| function Ult_Expanded_Prefix (N : Node_Id) return Node_Id is |
| (if Nkind (N) /= N_Expanded_Name |
| then N |
| else Ult_Expanded_Prefix (Prefix (N))); |
| -- Returns the ultimate prefix of an expanded name |
| |
| begin |
| if Chars (Entity (Ult_Expanded_Prefix (Nam))) = Chars (New_S) |
| then |
| Error_Msg_Sloc := Sloc (N); |
| Error_Msg_NE |
| ("& is hidden by declaration#", Nam, New_S); |
| end if; |
| end; |
| end if; |
| |
| Set_Convention (New_S, Convention (Old_S)); |
| |
| if Is_Abstract_Subprogram (Old_S) then |
| if Present (Rename_Spec) then |
| Error_Msg_N |
| ("a renaming-as-body cannot rename an abstract subprogram", |
| N); |
| Set_Has_Completion (Rename_Spec); |
| else |
| Set_Is_Abstract_Subprogram (New_S); |
| end if; |
| end if; |
| |
| Check_Library_Unit_Renaming (N, Old_S); |
| |
| -- Pathological case: procedure renames entry in the scope of its |
| -- task. Entry is given by simple name, but body must be built for |
| -- procedure. Of course if called it will deadlock. |
| |
| if Ekind (Old_S) = E_Entry then |
| Set_Has_Completion (New_S, False); |
| Set_Alias (New_S, Empty); |
| end if; |
| |
| -- Do not freeze the renaming nor the renamed entity when the context |
| -- is an enclosing generic. Freezing is an expansion activity, and in |
| -- addition the renamed entity may depend on the generic formals of |
| -- the enclosing generic. |
| |
| if Is_Actual and not Inside_A_Generic then |
| Freeze_Before (N, Old_S); |
| Freeze_Actual_Profile; |
| Set_Has_Delayed_Freeze (New_S, False); |
| Freeze_Before (N, New_S); |
| |
| if (Ekind (Old_S) = E_Procedure or else Ekind (Old_S) = E_Function) |
| and then not Is_Abstract_Subprogram (Formal_Spec) |
| then |
| -- An abstract subprogram is only allowed as an actual in the |
| -- case where the formal subprogram is also abstract. |
| |
| if Is_Abstract_Subprogram (Old_S) then |
| Error_Msg_N |
| ("abstract subprogram not allowed as generic actual", Nam); |
| end if; |
| |
| -- AI12-0412: A primitive of an abstract type with Pre'Class |
| -- or Post'Class aspects specified with nonstatic expressions |
| -- is not allowed as actual for a nonabstract formal subprogram |
| -- (see RM 6.1.1(18.2/5). |
| |
| if Is_Dispatching_Operation (Old_S) |
| and then |
| Is_Prim_Of_Abst_Type_With_Nonstatic_CW_Pre_Post (Old_S) |
| then |
| Error_Msg_N |
| ("primitive of abstract type with nonstatic class-wide " |
| & "pre/postconditions not allowed as actual", |
| Nam); |
| end if; |
| end if; |
| end if; |
| |
| else |
| -- A common error is to assume that implicit operators for types are |
| -- defined in Standard, or in the scope of a subtype. In those cases |
| -- where the renamed entity is given with an expanded name, it is |
| -- worth mentioning that operators for the type are not declared in |
| -- the scope given by the prefix. |
| |
| if Nkind (Nam) = N_Expanded_Name |
| and then Nkind (Selector_Name (Nam)) = N_Operator_Symbol |
| and then Scope (Entity (Nam)) = Standard_Standard |
| then |
| declare |
| T : constant Entity_Id := |
| Base_Type (Etype (First_Formal (New_S))); |
| begin |
| Error_Msg_Node_2 := Prefix (Nam); |
| Error_Msg_NE |
| ("operator for type& is not declared in&", Prefix (Nam), T); |
| end; |
| |
| else |
| Error_Msg_NE |
| ("no visible subprogram matches the specification for&", |
| Spec, New_S); |
| end if; |
| |
| if Present (Candidate_Renaming) then |
| declare |
| F1 : Entity_Id; |
| F2 : Entity_Id; |
| T1 : Entity_Id; |
| |
| begin |
| F1 := First_Formal (Candidate_Renaming); |
| F2 := First_Formal (New_S); |
| T1 := First_Subtype (Etype (F1)); |
| while Present (F1) and then Present (F2) loop |
| Next_Formal (F1); |
| Next_Formal (F2); |
| end loop; |
| |
| if Present (F1) and then Present (Default_Value (F1)) then |
| if Present (Next_Formal (F1)) then |
| Error_Msg_NE |
| ("\missing specification for & and other formals with " |
| & "defaults", Spec, F1); |
| else |
| Error_Msg_NE ("\missing specification for &", Spec, F1); |
| end if; |
| end if; |
| |
| if Nkind (Nam) = N_Operator_Symbol |
| and then From_Default (N) |
| then |
| Error_Msg_Node_2 := T1; |
| Error_Msg_NE |
| ("default & on & is not directly visible", Nam, Nam); |
| end if; |
| end; |
| end if; |
| end if; |
| |
| -- Ada 2005 AI 404: if the new subprogram is dispatching, verify that |
| -- controlling access parameters are known non-null for the renamed |
| -- subprogram. Test also applies to a subprogram instantiation that |
| -- is dispatching. Test is skipped if some previous error was detected |
| -- that set Old_S to Any_Id. |
| |
| if Ada_Version >= Ada_2005 |
| and then Old_S /= Any_Id |
| and then not Is_Dispatching_Operation (Old_S) |
| and then Is_Dispatching_Operation (New_S) |
| then |
| declare |
| Old_F : Entity_Id; |
| New_F : Entity_Id; |
| |
| begin |
| Old_F := First_Formal (Old_S); |
| New_F := First_Formal (New_S); |
| while Present (Old_F) loop |
| if Ekind (Etype (Old_F)) = E_Anonymous_Access_Type |
| and then Is_Controlling_Formal (New_F) |
| and then not Can_Never_Be_Null (Old_F) |
| then |
| Error_Msg_N ("access parameter is controlling,", New_F); |
| Error_Msg_NE |
| ("\corresponding parameter of& must be explicitly null " |
| & "excluding", New_F, Old_S); |
| end if; |
| |
| Next_Formal (Old_F); |
| Next_Formal (New_F); |
| end loop; |
| end; |
| end if; |
| |
| -- A useful warning, suggested by Ada Bug Finder (Ada-Europe 2005) |
| -- is to warn if an operator is being renamed as a different operator. |
| -- If the operator is predefined, examine the kind of the entity, not |
| -- the abbreviated declaration in Standard. |
| |
| if Comes_From_Source (N) |
| and then Present (Old_S) |
| and then (Nkind (Old_S) = N_Defining_Operator_Symbol |
| or else Ekind (Old_S) = E_Operator) |
| and then Nkind (New_S) = N_Defining_Operator_Symbol |
| and then Chars (Old_S) /= Chars (New_S) |
| then |
| Error_Msg_NE |
| ("& is being renamed as a different operator??", N, Old_S); |
| end if; |
| |
| -- Check for renaming of obsolescent subprogram |
| |
| Check_Obsolescent_2005_Entity (Entity (Nam), Nam); |
| |
| -- Another warning or some utility: if the new subprogram as the same |
| -- name as the old one, the old one is not hidden by an outer homograph, |
| -- the new one is not a public symbol, and the old one is otherwise |
| -- directly visible, the renaming is superfluous. |
| |
| if Chars (Old_S) = Chars (New_S) |
| and then Comes_From_Source (N) |
| and then Scope (Old_S) /= Standard_Standard |
| and then Warn_On_Redundant_Constructs |
| and then (Is_Immediately_Visible (Old_S) |
| or else Is_Potentially_Use_Visible (Old_S)) |
| and then Is_Overloadable (Current_Scope) |
| and then Chars (Current_Scope) /= Chars (Old_S) |
| then |
| Error_Msg_N |
| ("redundant renaming, entity is directly visible?r?", Name (N)); |
| end if; |
| |
| -- Implementation-defined aspect specifications can appear in a renaming |
| -- declaration, but not language-defined ones. The call to procedure |
| -- Analyze_Aspect_Specifications will take care of this error check. |
| |
| if Has_Aspects (N) then |
| Analyze_Aspect_Specifications (N, New_S); |
| end if; |
| |
| -- AI12-0279 |
| |
| if Is_Actual |
| and then Has_Yield_Aspect (Formal_Spec) |
| and then not Has_Yield_Aspect (Old_S) |
| then |
| Error_Msg_Name_1 := Name_Yield; |
| Error_Msg_N |
| ("actual subprogram& must have aspect% to match formal", Name (N)); |
| end if; |
| |
| Ada_Version := Save_AV; |
| Ada_Version_Pragma := Save_AVP; |
| Ada_Version_Explicit := Save_AV_Exp; |
| |
| -- Check if we are looking at an Ada 2012 defaulted formal subprogram |
| -- and mark any use_package_clauses that affect the visibility of the |
| -- implicit generic actual. |
| |
| -- Also, we may be looking at an internal renaming of a user-defined |
| -- subprogram created for a generic formal subprogram association, |
| -- which will also have to be marked here. This can occur when the |
| -- corresponding formal subprogram contains references to other generic |
| -- formals. |
| |
| if Is_Generic_Actual_Subprogram (New_S) |
| and then (Is_Intrinsic_Subprogram (New_S) |
| or else From_Default (N) |
| or else Nkind (N) = N_Subprogram_Renaming_Declaration) |
| then |
| Mark_Use_Clauses (New_S); |
| |
| -- Handle overloaded subprograms |
| |
| if Present (Alias (New_S)) then |
| Mark_Use_Clauses (Alias (New_S)); |
| end if; |
| end if; |
| end Analyze_Subprogram_Renaming; |
| |
| ------------------------- |
| -- Analyze_Use_Package -- |
| ------------------------- |
| |
| -- Resolve the package names in the use clause, and make all the visible |
| -- entities defined in the package potentially use-visible. If the package |
| -- is already in use from a previous use clause, its visible entities are |
| -- already use-visible. In that case, mark the occurrence as a redundant |
| -- use. If the package is an open scope, i.e. if the use clause occurs |
| -- within the package itself, ignore it. |
| |
| procedure Analyze_Use_Package (N : Node_Id; Chain : Boolean := True) is |
| procedure Analyze_Package_Name (Clause : Node_Id); |
| -- Perform analysis on a package name from a use_package_clause |
| |
| procedure Analyze_Package_Name_List (Head_Clause : Node_Id); |
| -- Similar to Analyze_Package_Name but iterates over all the names |
| -- in a use clause. |
| |
| -------------------------- |
| -- Analyze_Package_Name -- |
| -------------------------- |
| |
| procedure Analyze_Package_Name (Clause : Node_Id) is |
| Pack : constant Node_Id := Name (Clause); |
| Pref : Node_Id; |
| |
| begin |
| pragma Assert (Nkind (Clause) = N_Use_Package_Clause); |
| Analyze (Pack); |
| |
| -- Verify that the package standard is not directly named in a |
| -- use_package_clause. |
| |
| if Nkind (Parent (Clause)) = N_Compilation_Unit |
| and then Nkind (Pack) = N_Expanded_Name |
| then |
| Pref := Prefix (Pack); |
| |
| while Nkind (Pref) = N_Expanded_Name loop |
| Pref := Prefix (Pref); |
| end loop; |
| |
| if Entity (Pref) = Standard_Standard then |
| Error_Msg_N |
| ("predefined package Standard cannot appear in a context " |
| & "clause", Pref); |
| end if; |
| end if; |
| end Analyze_Package_Name; |
| |
| ------------------------------- |
| -- Analyze_Package_Name_List -- |
| ------------------------------- |
| |
| procedure Analyze_Package_Name_List (Head_Clause : Node_Id) is |
| Curr : Node_Id; |
| |
| begin |
| -- Due to the way source use clauses are split during parsing we are |
| -- forced to simply iterate through all entities in scope until the |
| -- clause representing the last name in the list is found. |
| |
| Curr := Head_Clause; |
| while Present (Curr) loop |
| Analyze_Package_Name (Curr); |
| |
| -- Stop iterating over the names in the use clause when we are at |
| -- the last one. |
| |
| exit when not More_Ids (Curr) and then Prev_Ids (Curr); |
| Next (Curr); |
| end loop; |
| end Analyze_Package_Name_List; |
| |
| -- Local variables |
| |
| Pack : Entity_Id; |
| |
| -- Start of processing for Analyze_Use_Package |
| |
| begin |
| Set_Hidden_By_Use_Clause (N, No_Elist); |
| |
| -- Use clause not allowed in a spec of a predefined package declaration |
| -- except that packages whose file name starts a-n are OK (these are |
| -- children of Ada.Numerics, which are never loaded by Rtsfind). |
| |
| if Is_Predefined_Unit (Current_Sem_Unit) |
| and then Get_Name_String |
| (Unit_File_Name (Current_Sem_Unit)) (1 .. 3) /= "a-n" |
| and then Nkind (Unit (Cunit (Current_Sem_Unit))) = |
| N_Package_Declaration |
| then |
| Error_Msg_N ("use clause not allowed in predefined spec", N); |
| end if; |
| |
| -- Loop through all package names from the original use clause in |
| -- order to analyze referenced packages. A use_package_clause with only |
| -- one name does not have More_Ids or Prev_Ids set, while a clause with |
| -- More_Ids only starts the chain produced by the parser. |
| |
| if not More_Ids (N) and then not Prev_Ids (N) then |
| Analyze_Package_Name (N); |
| |
| elsif More_Ids (N) and then not Prev_Ids (N) then |
| Analyze_Package_Name_List (N); |
| end if; |
| |
| if not Is_Entity_Name (Name (N)) then |
| Error_Msg_N ("& is not a package", Name (N)); |
| |
| return; |
| end if; |
| |
| if Chain then |
| Chain_Use_Clause (N); |
| end if; |
| |
| Pack := Entity (Name (N)); |
| |
| -- There are many cases where scopes are manipulated during analysis, so |
| -- check that Pack's current use clause has not already been chained |
| -- before setting its previous use clause. |
| |
| if Ekind (Pack) = E_Package |
| and then Present (Current_Use_Clause (Pack)) |
| and then Current_Use_Clause (Pack) /= N |
| and then No (Prev_Use_Clause (N)) |
| and then Prev_Use_Clause (Current_Use_Clause (Pack)) /= N |
| then |
| Set_Prev_Use_Clause (N, Current_Use_Clause (Pack)); |
| end if; |
| |
| -- Mark all entities as potentially use visible |
| |
| if Ekind (Pack) /= E_Package and then Etype (Pack) /= Any_Type then |
| if Ekind (Pack) = E_Generic_Package then |
| Error_Msg_N -- CODEFIX |
| ("a generic package is not allowed in a use clause", Name (N)); |
| |
| elsif Is_Generic_Subprogram (Pack) then |
| Error_Msg_N -- CODEFIX |
| ("a generic subprogram is not allowed in a use clause", |
| Name (N)); |
| |
| elsif Is_Subprogram (Pack) then |
| Error_Msg_N -- CODEFIX |
| ("a subprogram is not allowed in a use clause", Name (N)); |
| |
| else |
| Error_Msg_N ("& is not allowed in a use clause", Name (N)); |
| end if; |
| |
| else |
| if Nkind (Parent (N)) = N_Compilation_Unit then |
| Check_In_Previous_With_Clause (N, Name (N)); |
| end if; |
| |
| Use_One_Package (N, Name (N)); |
| end if; |
| |
| Mark_Ghost_Clause (N); |
| end Analyze_Use_Package; |
| |
| ---------------------- |
| -- Analyze_Use_Type -- |
| ---------------------- |
| |
| procedure Analyze_Use_Type (N : Node_Id; Chain : Boolean := True) is |
| E : Entity_Id; |
| Id : Node_Id; |
| |
| begin |
| Set_Hidden_By_Use_Clause (N, No_Elist); |
| |
| -- Chain clause to list of use clauses in current scope when flagged |
| |
| if Chain then |
| Chain_Use_Clause (N); |
| end if; |
| |
| -- Obtain the base type of the type denoted within the use_type_clause's |
| -- subtype mark. |
| |
| Id := Subtype_Mark (N); |
| Find_Type (Id); |
| E := Base_Type (Entity (Id)); |
| |
| -- There are many cases where a use_type_clause may be reanalyzed due to |
| -- manipulation of the scope stack so we much guard against those cases |
| -- here, otherwise, we must add the new use_type_clause to the previous |
| -- use_type_clause chain in order to mark redundant use_type_clauses as |
| -- used. When the redundant use-type clauses appear in a parent unit and |
| -- a child unit we must prevent a circularity in the chain that would |
| -- otherwise result from the separate steps of analysis and installation |
| -- of the parent context. |
| |
| if Present (Current_Use_Clause (E)) |
| and then Current_Use_Clause (E) /= N |
| and then Prev_Use_Clause (Current_Use_Clause (E)) /= N |
| and then No (Prev_Use_Clause (N)) |
| then |
| Set_Prev_Use_Clause (N, Current_Use_Clause (E)); |
| end if; |
| |
| -- If the Used_Operations list is already initialized, the clause has |
| -- been analyzed previously, and it is being reinstalled, for example |
| -- when the clause appears in a package spec and we are compiling the |
| -- corresponding package body. In that case, make the entities on the |
| -- existing list use_visible, and mark the corresponding types In_Use. |
| |
| if Present (Used_Operations (N)) then |
| declare |
| Elmt : Elmt_Id; |
| |
| begin |
| Use_One_Type (Subtype_Mark (N), Installed => True); |
| |
| Elmt := First_Elmt (Used_Operations (N)); |
| while Present (Elmt) loop |
| Set_Is_Potentially_Use_Visible (Node (Elmt)); |
| Next_Elmt (Elmt); |
| end loop; |
| end; |
| |
| return; |
| end if; |
| |
| -- Otherwise, create new list and attach to it the operations that are |
| -- made use-visible by the clause. |
| |
| Set_Used_Operations (N, New_Elmt_List); |
| E := Entity (Id); |
| |
| if E /= Any_Type then |
| Use_One_Type (Id); |
| |
| if Nkind (Parent (N)) = N_Compilation_Unit then |
| if Nkind (Id) = N_Identifier then |
| Error_Msg_N ("type is not directly visible", Id); |
| |
| elsif Is_Child_Unit (Scope (E)) |
| and then Scope (E) /= System_Aux_Id |
| then |
| Check_In_Previous_With_Clause (N, Prefix (Id)); |
| end if; |
| end if; |
| |
| else |
| -- If the use_type_clause appears in a compilation unit context, |
| -- check whether it comes from a unit that may appear in a |
| -- limited_with_clause, for a better error message. |
| |
| if Nkind (Parent (N)) = N_Compilation_Unit |
| and then Nkind (Id) /= N_Identifier |
| then |
| declare |
| Item : Node_Id; |
| Pref : Node_Id; |
| |
| function Mentioned (Nam : Node_Id) return Boolean; |
| -- Check whether the prefix of expanded name for the type |
| -- appears in the prefix of some limited_with_clause. |
| |
| --------------- |
| -- Mentioned -- |
| --------------- |
| |
| function Mentioned (Nam : Node_Id) return Boolean is |
| begin |
| return Nkind (Name (Item)) = N_Selected_Component |
| and then Chars (Prefix (Name (Item))) = Chars (Nam); |
| end Mentioned; |
| |
| begin |
| Pref := Prefix (Id); |
| Item := First (Context_Items (Parent (N))); |
| while Present (Item) and then Item /= N loop |
| if Nkind (Item) = N_With_Clause |
| and then Limited_Present (Item) |
| and then Mentioned (Pref) |
| then |
| Change_Error_Text |
| (Get_Msg_Id, "premature usage of incomplete type"); |
| end if; |
| |
| Next (Item); |
| end loop; |
| end; |
| end if; |
| end if; |
| |
| Mark_Ghost_Clause (N); |
| end Analyze_Use_Type; |
| |
| ------------------------ |
| -- Attribute_Renaming -- |
| ------------------------ |
| |
| procedure Attribute_Renaming (N : Node_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| Nam : constant Node_Id := Name (N); |
| Spec : constant Node_Id := Specification (N); |
| New_S : constant Entity_Id := Defining_Unit_Name (Spec); |
| Aname : constant Name_Id := Attribute_Name (Nam); |
| |
| Form_Num : Nat := 0; |
| Expr_List : List_Id := No_List; |
| |
| Attr_Node : Node_Id; |
| Body_Node : Node_Id; |
| Param_Spec : Node_Id; |
| |
| begin |
| Generate_Definition (New_S); |
| |
| -- This procedure is called in the context of subprogram renaming, and |
| -- thus the attribute must be one that is a subprogram. All of those |
| -- have at least one formal parameter, with the exceptions of the GNAT |
| -- attribute 'Img, which GNAT treats as renameable. |
| |
| if Is_Empty_List (Parameter_Specifications (Spec)) then |
| if Aname /= Name_Img then |
| Error_Msg_N |
| ("subprogram renaming an attribute must have formals", N); |
| return; |
| end if; |
| |
| else |
| Param_Spec := First (Parameter_Specifications (Spec)); |
| while Present (Param_Spec) loop |
| Form_Num := Form_Num + 1; |
| |
| if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then |
| Find_Type (Parameter_Type (Param_Spec)); |
| |
| -- The profile of the new entity denotes the base type (s) of |
| -- the types given in the specification. For access parameters |
| -- there are no subtypes involved. |
| |
| Rewrite (Parameter_Type (Param_Spec), |
| New_Occurrence_Of |
| (Base_Type (Entity (Parameter_Type (Param_Spec))), Loc)); |
| end if; |
| |
| if No (Expr_List) then |
| Expr_List := New_List; |
| end if; |
| |
| Append_To (Expr_List, |
| Make_Identifier (Loc, |
| Chars => Chars (Defining_Identifier (Param_Spec)))); |
| |
| -- The expressions in the attribute reference are not freeze |
| -- points. Neither is the attribute as a whole, see below. |
| |
| Set_Must_Not_Freeze (Last (Expr_List)); |
| Next (Param_Spec); |
| end loop; |
| end if; |
| |
| -- Immediate error if too many formals. Other mismatches in number or |
| -- types of parameters are detected when we analyze the body of the |
| -- subprogram that we construct. |
| |
| if Form_Num > 2 then |
| Error_Msg_N ("too many formals for attribute", N); |
| |
| -- Error if the attribute reference has expressions that look like |
| -- formal parameters. |
| |
| elsif Present (Expressions (Nam)) then |
| Error_Msg_N ("illegal expressions in attribute reference", Nam); |
| |
| elsif Aname in Name_Compose | Name_Exponent | Name_Leading_Part | |
| Name_Pos | Name_Round | Name_Scaling | |
| Name_Val |
| then |
| if Nkind (N) = N_Subprogram_Renaming_Declaration |
| and then Present (Corresponding_Formal_Spec (N)) |
| then |
| Error_Msg_N |
| ("generic actual cannot be attribute involving universal type", |
| Nam); |
| else |
| Error_Msg_N |
| ("attribute involving a universal type cannot be renamed", |
| Nam); |
| end if; |
| end if; |
| |
| -- Rewrite attribute node to have a list of expressions corresponding to |
| -- the subprogram formals. A renaming declaration is not a freeze point, |
| -- and the analysis of the attribute reference should not freeze the |
| -- type of the prefix. We use the original node in the renaming so that |
| -- its source location is preserved, and checks on stream attributes are |
| -- properly applied. |
| |
| Attr_Node := Relocate_Node (Nam); |
| Set_Expressions (Attr_Node, Expr_List); |
| |
| Set_Must_Not_Freeze (Attr_Node); |
| Set_Must_Not_Freeze (Prefix (Nam)); |
| |
| -- Case of renaming a function |
| |
| if Nkind (Spec) = N_Function_Specification then |
| if Is_Procedure_Attribute_Name (Aname) then |
| Error_Msg_N ("attribute can only be renamed as procedure", Nam); |
| return; |
| end if; |
| |
| Find_Type (Result_Definition (Spec)); |
| Rewrite (Result_Definition (Spec), |
| New_Occurrence_Of |
| (Base_Type (Entity (Result_Definition (Spec))), Loc)); |
| |
| Body_Node := |
| Make_Subprogram_Body (Loc, |
| Specification => Spec, |
| Declarations => New_List, |
| Handled_Statement_Sequence => |
| Make_Handled_Sequence_Of_Statements (Loc, |
| Statements => New_List ( |
| Make_Simple_Return_Statement (Loc, |
| Expression => Attr_Node)))); |
| |
| -- Case of renaming a procedure |
| |
| else |
| if not Is_Procedure_Attribute_Name (Aname) then |
| Error_Msg_N ("attribute can only be renamed as function", Nam); |
| return; |
| end if; |
| |
| Body_Node := |
| Make_Subprogram_Body (Loc, |
| Specification => Spec, |
| Declarations => New_List, |
| Handled_Statement_Sequence => |
| Make_Handled_Sequence_Of_Statements (Loc, |
| Statements => New_List (Attr_Node))); |
| end if; |
| |
| -- Signal the ABE mechanism that the generated subprogram body has not |
| -- ABE ramifications. |
| |
| Set_Was_Attribute_Reference (Body_Node); |
| |
| -- In case of tagged types we add the body of the generated function to |
| -- the freezing actions of the type (because in the general case such |
| -- type is still not frozen). We exclude from this processing generic |
| -- formal subprograms found in instantiations. |
| |
| -- We must exclude restricted run-time libraries because |
| -- entity AST_Handler is defined in package System.Aux_Dec which is not |
| -- available in those platforms. Note that we cannot use the function |
| -- Restricted_Profile (instead of Configurable_Run_Time_Mode) because |
| -- the ZFP run-time library is not defined as a profile, and we do not |
| -- want to deal with AST_Handler in ZFP mode. |
| |
| if not Configurable_Run_Time_Mode |
| and then No (Corresponding_Formal_Spec (N)) |
| and then not Is_RTE (Etype (Nam), RE_AST_Handler) |
| then |
| declare |
| P : constant Node_Id := Prefix (Nam); |
| |
| begin |
| -- The prefix of 'Img is an object that is evaluated for each call |
| -- of the function that renames it. |
| |
| if Aname = Name_Img then |
| Preanalyze_And_Resolve (P); |
| |
| -- For all other attribute renamings, the prefix is a subtype |
| |
| else |
| Find_Type (P); |
| end if; |
| |
| -- If the target type is not yet frozen, add the body to the |
| -- actions to be elaborated at freeze time. |
| |
| if Is_Tagged_Type (Etype (P)) |
| and then In_Open_Scopes (Scope (Etype (P))) |
| then |
| Append_Freeze_Action (Etype (P), Body_Node); |
| else |
| Rewrite (N, Body_Node); |
| Analyze (N); |
| Set_Etype (New_S, Base_Type (Etype (New_S))); |
| end if; |
| end; |
| |
| -- Generic formal subprograms or AST_Handler renaming |
| |
| else |
| Rewrite (N, Body_Node); |
| Analyze (N); |
| Set_Etype (New_S, Base_Type (Etype (New_S))); |
| end if; |
| |
| if Is_Compilation_Unit (New_S) then |
| Error_Msg_N |
| ("a library unit can only rename another library unit", N); |
| end if; |
| |
| -- We suppress elaboration warnings for the resulting entity, since |
| -- clearly they are not needed, and more particularly, in the case |
| -- of a generic formal subprogram, the resulting entity can appear |
| -- after the instantiation itself, and thus look like a bogus case |
| -- of access before elaboration. |
| |
| if Legacy_Elaboration_Checks then |
| Set_Suppress_Elaboration_Warnings (New_S); |
| end if; |
| end Attribute_Renaming; |
| |
| ---------------------- |
| -- Chain_Use_Clause -- |
| ---------------------- |
| |
| procedure Chain_Use_Clause (N : Node_Id) is |
| Level : Int := Scope_Stack.Last; |
| Pack : Entity_Id; |
| |
| begin |
| -- Common case |
| |
| if not Is_Compilation_Unit (Current_Scope) |
| or else not Is_Child_Unit (Current_Scope) |
| then |
| null; |
| |
| -- Common case for compilation unit |
| |
| elsif Defining_Entity (Parent (N)) = Current_Scope then |
| null; |
| |
| else |
| -- If declaration appears in some other scope, it must be in some |
| -- parent unit when compiling a child. |
| |
| Pack := Defining_Entity (Parent (N)); |
| |
| if not In_Open_Scopes (Pack) then |
| null; |
| |
| -- If the use clause appears in an ancestor and we are in the |
| -- private part of the immediate parent, the use clauses are |
| -- already installed. |
| |
| elsif Pack /= Scope (Current_Scope) |
| and then In_Private_Part (Scope (Current_Scope)) |
| then |
| null; |
| |
| else |
| -- Find entry for parent unit in scope stack |
| |
| while Scope_Stack.Table (Level).Entity /= Pack loop |
| Level := Level - 1; |
| end loop; |
| end if; |
| end if; |
| |
| Set_Next_Use_Clause (N, |
| Scope_Stack.Table (Level).First_Use_Clause); |
| Scope_Stack.Table (Level).First_Use_Clause := N; |
| end Chain_Use_Clause; |
| |
| --------------------------- |
| -- Check_Frozen_Renaming -- |
| --------------------------- |
| |
| procedure Check_Frozen_Renaming (N : Node_Id; Subp : Entity_Id) is |
| B_Node : Node_Id; |
| Old_S : Entity_Id; |
| |
| begin |
| if Is_Frozen (Subp) and then not Has_Completion (Subp) then |
| B_Node := |
| Build_Renamed_Body |
| (Parent (Declaration_Node (Subp)), Defining_Entity (N)); |
| |
| if Is_Entity_Name (Name (N)) then |
| Old_S := Entity (Name (N)); |
| |
| if not Is_Frozen (Old_S) |
| and then Operating_Mode /= Check_Semantics |
| then |
| Append_Freeze_Action (Old_S, B_Node); |
| else |
| Insert_After (N, B_Node); |
| Analyze (B_Node); |
| end if; |
| |
| if Is_Intrinsic_Subprogram (Old_S) |
| and then not In_Instance |
| and then not Relaxed_RM_Semantics |
| then |
| Error_Msg_N |
| ("subprogram used in renaming_as_body cannot be intrinsic", |
| Name (N)); |
| end if; |
| |
| else |
| Insert_After (N, B_Node); |
| Analyze (B_Node); |
| end if; |
| end if; |
| end Check_Frozen_Renaming; |
| |
| ------------------------------- |
| -- Set_Entity_Or_Discriminal -- |
| ------------------------------- |
| |
| procedure Set_Entity_Or_Discriminal (N : Node_Id; E : Entity_Id) is |
| P : Node_Id; |
| |
| begin |
| -- If the entity is not a discriminant, or else expansion is disabled, |
| -- simply set the entity. |
| |
| if not In_Spec_Expression |
| or else Ekind (E) /= E_Discriminant |
| or else Inside_A_Generic |
| then |
| Set_Entity_With_Checks (N, E); |
| |
| -- The replacement of a discriminant by the corresponding discriminal |
| -- is not done for a task discriminant that appears in a default |
| -- expression of an entry parameter. See Exp_Ch2.Expand_Discriminant |
| -- for details on their handling. |
| |
| elsif Is_Concurrent_Type (Scope (E)) then |
| P := Parent (N); |
| while Present (P) |
| and then Nkind (P) not in |
| N_Parameter_Specification | N_Component_Declaration |
| loop |
| P := Parent (P); |
| end loop; |
| |
| if Present (P) |
| and then Nkind (P) = N_Parameter_Specification |
| then |
| null; |
| |
| else |
| Set_Entity (N, Discriminal (E)); |
| end if; |
| |
| -- Otherwise, this is a discriminant in a context in which |
| -- it is a reference to the corresponding parameter of the |
| -- init proc for the enclosing type. |
| |
| else |
| Set_Entity (N, Discriminal (E)); |
| end if; |
| end Set_Entity_Or_Discriminal; |
| |
| ----------------------------------- |
| -- Check_In_Previous_With_Clause -- |
| ----------------------------------- |
| |
| procedure Check_In_Previous_With_Clause (N, Nam : Node_Id) is |
| Pack : constant Entity_Id := Entity (Original_Node (Nam)); |
| Item : Node_Id; |
| Par : Node_Id; |
| |
| begin |
| Item := First (Context_Items (Parent (N))); |
| while Present (Item) and then Item /= N loop |
| if Nkind (Item) = N_With_Clause |
| |
| -- Protect the frontend against previous critical errors |
| |
| and then Nkind (Name (Item)) /= N_Selected_Component |
| and then Entity (Name (Item)) = Pack |
| then |
| Par := Nam; |
| |
| -- Find root library unit in with_clause |
| |
| while Nkind (Par) = N_Expanded_Name loop |
| Par := Prefix (Par); |
| end loop; |
| |
| if Is_Child_Unit (Entity (Original_Node (Par))) then |
| Error_Msg_NE ("& is not directly visible", Par, Entity (Par)); |
| else |
| return; |
| end if; |
| end if; |
| |
| Next (Item); |
| end loop; |
| |
| -- On exit, package is not mentioned in a previous with_clause. |
| -- Check if its prefix is. |
| |
| if Nkind (Nam) = N_Expanded_Name then |
| Check_In_Previous_With_Clause (N, Prefix (Nam)); |
| |
| elsif Pack /= Any_Id then |
| Error_Msg_NE ("& is not visible", Nam, Pack); |
| end if; |
| end Check_In_Previous_With_Clause; |
| |
| --------------------------------- |
| -- Check_Library_Unit_Renaming -- |
| --------------------------------- |
| |
| procedure Check_Library_Unit_Renaming (N : Node_Id; Old_E : Entity_Id) is |
| New_E : Entity_Id; |
| |
| begin |
| if Nkind (Parent (N)) /= N_Compilation_Unit then |
| return; |
| |
| -- Check for library unit. Note that we used to check for the scope |
| -- being Standard here, but that was wrong for Standard itself. |
| |
| elsif not Is_Compilation_Unit (Old_E) |
| and then not Is_Child_Unit (Old_E) |
| then |
| Error_Msg_N ("renamed unit must be a library unit", Name (N)); |
| |
| -- Entities defined in Standard (operators and boolean literals) cannot |
| -- be renamed as library units. |
| |
| elsif Scope (Old_E) = Standard_Standard |
| and then Sloc (Old_E) = Standard_Location |
| then |
| Error_Msg_N ("renamed unit must be a library unit", Name (N)); |
| |
| elsif Present (Parent_Spec (N)) |
| and then Nkind (Unit (Parent_Spec (N))) = N_Generic_Package_Declaration |
| and then not Is_Child_Unit (Old_E) |
| then |
| Error_Msg_N |
| ("renamed unit must be a child unit of generic parent", Name (N)); |
| |
| elsif Nkind (N) in N_Generic_Renaming_Declaration |
| and then Nkind (Name (N)) = N_Expanded_Name |
| and then Is_Generic_Instance (Entity (Prefix (Name (N)))) |
| and then Is_Generic_Unit (Old_E) |
| then |
| Error_Msg_N |
| ("renamed generic unit must be a library unit", Name (N)); |
| |
| elsif Is_Package_Or_Generic_Package (Old_E) then |
| |
| -- Inherit categorization flags |
| |
| New_E := Defining_Entity (N); |
| Set_Is_Pure (New_E, Is_Pure (Old_E)); |
| Set_Is_Preelaborated (New_E, Is_Preelaborated (Old_E)); |
| Set_Is_Remote_Call_Interface (New_E, |
| Is_Remote_Call_Interface (Old_E)); |
| Set_Is_Remote_Types (New_E, Is_Remote_Types (Old_E)); |
| Set_Is_Shared_Passive (New_E, Is_Shared_Passive (Old_E)); |
| end if; |
| end Check_Library_Unit_Renaming; |
| |
| ------------------------ |
| -- Enclosing_Instance -- |
| ------------------------ |
| |
| function Enclosing_Instance return Entity_Id is |
| S : Entity_Id; |
| |
| begin |
| if not Is_Generic_Instance (Current_Scope) then |
| return Empty; |
| end if; |
| |
| S := Scope (Current_Scope); |
| while S /= Standard_Standard loop |
| if Is_Generic_Instance (S) then |
| return S; |
| end if; |
| |
| S := Scope (S); |
| end loop; |
| |
| return Empty; |
| end Enclosing_Instance; |
| |
| --------------- |
| -- End_Scope -- |
| --------------- |
| |
| procedure End_Scope is |
| Id : Entity_Id; |
| Prev : Entity_Id; |
| Outer : Entity_Id; |
| |
| begin |
| Id := First_Entity (Current_Scope); |
| while Present (Id) loop |
| -- An entity in the current scope is not necessarily the first one |
| -- on its homonym chain. Find its predecessor if any, |
| -- If it is an internal entity, it will not be in the visibility |
| -- chain altogether, and there is nothing to unchain. |
| |
| if Id /= Current_Entity (Id) then |
| Prev := Current_Entity (Id); |
| while Present (Prev) |
| and then Present (Homonym (Prev)) |
| and then Homonym (Prev) /= Id |
| loop |
| Prev := Homonym (Prev); |
| end loop; |
| |
| -- Skip to end of loop if Id is not in the visibility chain |
| |
| if No (Prev) or else Homonym (Prev) /= Id then |
| goto Next_Ent; |
| end if; |
| |
| else |
| Prev := Empty; |
| end if; |
| |
| Set_Is_Immediately_Visible (Id, False); |
| |
| Outer := Homonym (Id); |
| while Present (Outer) and then Scope (Outer) = Current_Scope loop |
| Outer := Homonym (Outer); |
| end loop; |
| |
| -- Reset homonym link of other entities, but do not modify link |
| -- between entities in current scope, so that the back-end can have |
| -- a proper count of local overloadings. |
| |
| if No (Prev) then |
| Set_Name_Entity_Id (Chars (Id), Outer); |
| |
| elsif Scope (Prev) /= Scope (Id) then |
| Set_Homonym (Prev, Outer); |
| end if; |
| |
| <<Next_Ent>> |
| Next_Entity (Id); |
| end loop; |
| |
| -- If the scope generated freeze actions, place them before the |
| -- current declaration and analyze them. Type declarations and |
| -- the bodies of initialization procedures can generate such nodes. |
| -- We follow the parent chain until we reach a list node, which is |
| -- the enclosing list of declarations. If the list appears within |
| -- a protected definition, move freeze nodes outside the protected |
| -- type altogether. |
| |
| if Present |
| (Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions) |
| then |
| declare |
| Decl : Node_Id; |
| L : constant List_Id := Scope_Stack.Table |
| (Scope_Stack.Last).Pending_Freeze_Actions; |
| |
| begin |
| if Is_Itype (Current_Scope) then |
| Decl := Associated_Node_For_Itype (Current_Scope); |
| else |
| Decl := Parent (Current_Scope); |
| end if; |
| |
| Pop_Scope; |
| |
| while not Is_List_Member (Decl) |
| or else Nkind (Parent (Decl)) in N_Protected_Definition |
| | N_Task_Definition |
| loop |
| Decl := Parent (Decl); |
| end loop; |
| |
| Insert_List_Before_And_Analyze (Decl, L); |
| end; |
| |
| else |
| Pop_Scope; |
| end if; |
| end End_Scope; |
| |
| --------------------- |
| -- End_Use_Clauses -- |
| --------------------- |
| |
| procedure End_Use_Clauses (Clause : Node_Id) is |
| U : Node_Id; |
| |
| begin |
| -- Remove use_type_clauses first, because they affect the visibility of |
| -- operators in subsequent used packages. |
| |
| U := Clause; |
| while Present (U) loop |
| if Nkind (U) = N_Use_Type_Clause then |
| End_Use_Type (U); |
| end if; |
| |
| Next_Use_Clause (U); |
| end loop; |
| |
| U := Clause; |
| while Present (U) loop |
| if Nkind (U) = N_Use_Package_Clause then |
| End_Use_Package (U); |
| end if; |
| |
| Next_Use_Clause (U); |
| end loop; |
| end End_Use_Clauses; |
| |
| --------------------- |
| -- End_Use_Package -- |
| --------------------- |
| |
| procedure End_Use_Package (N : Node_Id) is |
| Pack : Entity_Id; |
| Pack_Name : Node_Id; |
| Id : Entity_Id; |
| Elmt : Elmt_Id; |
| |
| function Is_Primitive_Operator_In_Use |
| (Op : Entity_Id; |
| F : Entity_Id) return Boolean; |
| -- Check whether Op is a primitive operator of a use-visible type |
| |
| ---------------------------------- |
| -- Is_Primitive_Operator_In_Use -- |
| ---------------------------------- |
| |
| function Is_Primitive_Operator_In_Use |
| (Op : Entity_Id; |
| F : Entity_Id) return Boolean |
| is |
| T : constant Entity_Id := Base_Type (Etype (F)); |
| begin |
| return In_Use (T) and then Scope (T) = Scope (Op); |
| end Is_Primitive_Operator_In_Use; |
| |
| -- Start of processing for End_Use_Package |
| |
| begin |
| Pack_Name := Name (N); |
| |
| -- Test that Pack_Name actually denotes a package before processing |
| |
| if Is_Entity_Name (Pack_Name) |
| and then Ekind (Entity (Pack_Name)) = E_Package |
| then |
| Pack := Entity (Pack_Name); |
| |
| if In_Open_Scopes (Pack) then |
| null; |
| |
| elsif not Redundant_Use (Pack_Name) then |
| Set_In_Use (Pack, False); |
| Set_Current_Use_Clause (Pack, Empty); |
| |
| Id := First_Entity (Pack); |
| while Present (Id) loop |
| |
| -- Preserve use-visibility of operators that are primitive |
| -- operators of a type that is use-visible through an active |
| -- use_type_clause. |
| |
| if Nkind (Id) = N_Defining_Operator_Symbol |
| and then |
| (Is_Primitive_Operator_In_Use (Id, First_Formal (Id)) |
| or else |
| (Present (Next_Formal (First_Formal (Id))) |
| and then |
| Is_Primitive_Operator_In_Use |
| (Id, Next_Formal (First_Formal (Id))))) |
| then |
| null; |
| else |
| Set_Is_Potentially_Use_Visible (Id, False); |
| end if; |
| |
| if Is_Private_Type (Id) |
| and then Present (Full_View (Id)) |
| then |
| Set_Is_Potentially_Use_Visible (Full_View (Id), False); |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| if Present (Renamed_Entity (Pack)) then |
| Set_In_Use (Renamed_Entity (Pack), False); |
| Set_Current_Use_Clause (Renamed_Entity (Pack), Empty); |
| end if; |
| |
| if Chars (Pack) = Name_System |
| and then Scope (Pack) = Standard_Standard |
| and then Present_System_Aux |
| then |
| Id := First_Entity (System_Aux_Id); |
| while Present (Id) loop |
| Set_Is_Potentially_Use_Visible (Id, False); |
| |
| if Is_Private_Type (Id) |
| and then Present (Full_View (Id)) |
| then |
| Set_Is_Potentially_Use_Visible (Full_View (Id), False); |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| Set_In_Use (System_Aux_Id, False); |
| end if; |
| else |
| Set_Redundant_Use (Pack_Name, False); |
| end if; |
| end if; |
| |
| if Present (Hidden_By_Use_Clause (N)) then |
| Elmt := First_Elmt (Hidden_By_Use_Clause (N)); |
| while Present (Elmt) loop |
| declare |
| E : constant Entity_Id := Node (Elmt); |
| |
| begin |
| -- Reset either Use_Visibility or Direct_Visibility, depending |
| -- on how the entity was hidden by the use clause. |
| |
| if In_Use (Scope (E)) |
| and then Used_As_Generic_Actual (Scope (E)) |
| then |
| Set_Is_Potentially_Use_Visible (Node (Elmt)); |
| else |
| Set_Is_Immediately_Visible (Node (Elmt)); |
| end if; |
| |
| Next_Elmt (Elmt); |
| end; |
| end loop; |
| |
| Set_Hidden_By_Use_Clause (N, No_Elist); |
| end if; |
| end End_Use_Package; |
| |
| ------------------ |
| -- End_Use_Type -- |
| ------------------ |
| |
| procedure End_Use_Type (N : Node_Id) is |
| Elmt : Elmt_Id; |
| Id : Entity_Id; |
| T : Entity_Id; |
| |
| -- Start of processing for End_Use_Type |
| |
| begin |
| Id := Subtype_Mark (N); |
| |
| -- A call to Rtsfind may occur while analyzing a use_type_clause, in |
| -- which case the type marks are not resolved yet, so guard against that |
| -- here. |
| |
| if Is_Entity_Name (Id) and then Present (Entity (Id)) then |
| T := Entity (Id); |
| |
| if T = Any_Type or else From_Limited_With (T) then |
| null; |
| |
| -- Note that the use_type_clause may mention a subtype of the type |
| -- whose primitive operations have been made visible. Here as |
| -- elsewhere, it is the base type that matters for visibility. |
| |
| elsif In_Open_Scopes (Scope (Base_Type (T))) then |
| null; |
| |
| elsif not Redundant_Use (Id) then |
| Set_In_Use (T, False); |
| Set_In_Use (Base_Type (T), False); |
| Set_Current_Use_Clause (T, Empty); |
| Set_Current_Use_Clause (Base_Type (T), Empty); |
| |
| -- See Use_One_Type for the rationale. This is a bit on the naive |
| -- side, but should be good enough in practice. |
| |
| if Is_Tagged_Type (T) then |
| Set_In_Use (Class_Wide_Type (T), False); |
| end if; |
| end if; |
| end if; |
| |
| if Is_Empty_Elmt_List (Used_Operations (N)) then |
| return; |
| |
| else |
| Elmt := First_Elmt (Used_Operations (N)); |
| while Present (Elmt) loop |
| Set_Is_Potentially_Use_Visible (Node (Elmt), False); |
| Next_Elmt (Elmt); |
| end loop; |
| end if; |
| end End_Use_Type; |
| |
| -------------------- |
| -- Entity_Of_Unit -- |
| -------------------- |
| |
| function Entity_Of_Unit (U : Node_Id) return Entity_Id is |
| begin |
| if Nkind (U) = N_Package_Instantiation and then Analyzed (U) then |
| return Defining_Entity (Instance_Spec (U)); |
| else |
| return Defining_Entity (U); |
| end if; |
| end Entity_Of_Unit; |
| |
| -------------------------------------- |
| -- Error_Missing_With_Of_Known_Unit -- |
| -------------------------------------- |
| |
| procedure Error_Missing_With_Of_Known_Unit (Pkg : Node_Id) is |
| Selectors : array (1 .. 6) of Node_Id; |
| -- Contains the chars of the full package name up to maximum number |
| -- allowed as per Errout.Error_Msg_Name_# variables. |
| |
| Count : Integer := Selectors'First; |
| -- Count of selector names forming the full package name |
| |
| Current_Pkg : Node_Id := Parent (Pkg); |
| |
| begin |
| Selectors (Count) := Pkg; |
| |
| -- Gather all the selectors we can display |
| |
| while Nkind (Current_Pkg) = N_Selected_Component |
| and then Is_Known_Unit (Current_Pkg) |
| and then Count < Selectors'Length |
| loop |
| Count := Count + 1; |
| Selectors (Count) := Selector_Name (Current_Pkg); |
| Current_Pkg := Parent (Current_Pkg); |
| end loop; |
| |
| -- Display the error message based on the number of selectors found |
| |
| case Count is |
| when 1 => |
| Error_Msg_Node_1 := Selectors (1); |
| Error_Msg_N -- CODEFIX |
| ("\\missing `WITH &;`", Pkg); |
| when 2 => |
| Error_Msg_Node_1 := Selectors (1); |
| Error_Msg_Node_2 := Selectors (2); |
| Error_Msg_N -- CODEFIX |
| ("\\missing `WITH &.&;`", Pkg); |
| when 3 => |
| Error_Msg_Node_1 := Selectors (1); |
| Error_Msg_Node_2 := Selectors (2); |
| Error_Msg_Node_3 := Selectors (3); |
| Error_Msg_N -- CODEFIX |
| ("\\missing `WITH &.&.&;`", Pkg); |
| when 4 => |
| Error_Msg_Node_1 := Selectors (1); |
| Error_Msg_Node_2 := Selectors (2); |
| Error_Msg_Node_3 := Selectors (3); |
| Error_Msg_Node_3 := Selectors (4); |
| Error_Msg_N -- CODEFIX |
| ("\\missing `WITH &.&.&.&;`", Pkg); |
| when 5 => |
| Error_Msg_Node_1 := Selectors (1); |
| Error_Msg_Node_2 := Selectors (2); |
| Error_Msg_Node_3 := Selectors (3); |
| Error_Msg_Node_3 := Selectors (4); |
| Error_Msg_Node_3 := Selectors (5); |
| Error_Msg_N -- CODEFIX |
| ("\\missing `WITH &.&.&.&.&;`", Pkg); |
| when 6 => |
| Error_Msg_Node_1 := Selectors (1); |
| Error_Msg_Node_2 := Selectors (2); |
| Error_Msg_Node_3 := Selectors (3); |
| Error_Msg_Node_4 := Selectors (4); |
| Error_Msg_Node_5 := Selectors (5); |
| Error_Msg_Node_6 := Selectors (6); |
| Error_Msg_N -- CODEFIX |
| ("\\missing `WITH &.&.&.&.&.&;`", Pkg); |
| when others => |
| raise Program_Error; |
| end case; |
| end Error_Missing_With_Of_Known_Unit; |
| |
| ---------------------- |
| -- Find_Direct_Name -- |
| ---------------------- |
| |
| procedure Find_Direct_Name (N : Node_Id) is |
| E : Entity_Id; |
| E2 : Entity_Id; |
| Msg : Boolean; |
| |
| Homonyms : Entity_Id; |
| -- Saves start of homonym chain |
| |
| Inst : Entity_Id := Empty; |
| -- Enclosing instance, if any |
| |
| Nvis_Entity : Boolean; |
| -- Set True to indicate that there is at least one entity on the homonym |
| -- chain which, while not visible, is visible enough from the user point |
| -- of view to warrant an error message of "not visible" rather than |
| -- undefined. |
| |
| Nvis_Is_Private_Subprg : Boolean := False; |
| -- Ada 2005 (AI-262): Set True to indicate that a form of Beaujolais |
| -- effect concerning library subprograms has been detected. Used to |
| -- generate the precise error message. |
| |
| function From_Actual_Package (E : Entity_Id) return Boolean; |
| -- Returns true if the entity is an actual for a package that is itself |
| -- an actual for a formal package of the current instance. Such an |
| -- entity requires special handling because it may be use-visible but |
| -- hides directly visible entities defined outside the instance, because |
| -- the corresponding formal did so in the generic. |
| |
| function Is_Actual_Parameter return Boolean; |
| -- This function checks if the node N is an identifier that is an actual |
| -- parameter of a procedure call. If so it returns True, otherwise it |
| -- return False. The reason for this check is that at this stage we do |
| -- not know what procedure is being called if the procedure might be |
| -- overloaded, so it is premature to go setting referenced flags or |
| -- making calls to Generate_Reference. We will wait till Resolve_Actuals |
| -- for that processing. |
| -- Note: there is a similar routine Sem_Util.Is_Actual_Parameter, but |
| -- it works for both function and procedure calls, while here we are |
| -- only concerned with procedure calls (and with entry calls as well, |
| -- but they are parsed as procedure calls and only later rewritten to |
| -- entry calls). |
| |
| function Known_But_Invisible (E : Entity_Id) return Boolean; |
| -- This function determines whether a reference to the entity E, which |
| -- is not visible, can reasonably be considered to be known to the |
| -- writer of the reference. This is a heuristic test, used only for |
| -- the purposes of figuring out whether we prefer to complain that an |
| -- entity is undefined or invisible (and identify the declaration of |
| -- the invisible entity in the latter case). The point here is that we |
| -- don't want to complain that something is invisible and then point to |
| -- something entirely mysterious to the writer. |
| |
| procedure Nvis_Messages; |
| -- Called if there are no visible entries for N, but there is at least |
| -- one non-directly visible, or hidden declaration. This procedure |
| -- outputs an appropriate set of error messages. |
| |
| procedure Undefined (Nvis : Boolean); |
| -- This function is called if the current node has no corresponding |
| -- visible entity or entities. The value set in Msg indicates whether |
| -- an error message was generated (multiple error messages for the |
| -- same variable are generally suppressed, see body for details). |
| -- Msg is True if an error message was generated, False if not. This |
| -- value is used by the caller to determine whether or not to output |
| -- additional messages where appropriate. The parameter is set False |
| -- to get the message "X is undefined", and True to get the message |
| -- "X is not visible". |
| |
| ------------------------- |
| -- From_Actual_Package -- |
| ------------------------- |
| |
| function From_Actual_Package (E : Entity_Id) return Boolean is |
| Scop : constant Entity_Id := Scope (E); |
| -- Declared scope of candidate entity |
| |
| function Declared_In_Actual (Pack : Entity_Id) return Boolean; |
| -- Recursive function that does the work and examines actuals of |
| -- actual packages of current instance. |
| |
| ------------------------ |
| -- Declared_In_Actual -- |
| ------------------------ |
| |
| function Declared_In_Actual (Pack : Entity_Id) return Boolean is |
| pragma Assert (Ekind (Pack) = E_Package); |
| Act : Entity_Id; |
| begin |
| if No (Associated_Formal_Package (Pack)) then |
| return False; |
| |
| else |
| Act := First_Entity (Pack); |
| while Present (Act) loop |
| if Renamed_Entity (Pack) = Scop then |
| return True; |
| |
| -- Check for end of list of actuals |
| |
| elsif Ekind (Act) = E_Package |
| and then Renamed_Entity (Act) = Pack |
| then |
| return False; |
| |
| elsif Ekind (Act) = E_Package |
| and then Declared_In_Actual (Act) |
| then |
| return True; |
| end if; |
| |
| Next_Entity (Act); |
| end loop; |
| |
| return False; |
| end if; |
| end Declared_In_Actual; |
| |
| -- Local variables |
| |
| Act : Entity_Id; |
| |
| -- Start of processing for From_Actual_Package |
| |
| begin |
| if not In_Instance then |
| return False; |
| |
| else |
| Inst := Current_Scope; |
| while Present (Inst) |
| and then Ekind (Inst) /= E_Package |
| and then not Is_Generic_Instance (Inst) |
| loop |
| Inst := Scope (Inst); |
| end loop; |
| |
| if No (Inst) then |
| return False; |
| end if; |
| |
| Act := First_Entity (Inst); |
| while Present (Act) loop |
| if Ekind (Act) = E_Package |
| and then Declared_In_Actual (Act) |
| then |
| return True; |
| end if; |
| |
| Next_Entity (Act); |
| end loop; |
| |
| return False; |
| end if; |
| end From_Actual_Package; |
| |
| ------------------------- |
| -- Is_Actual_Parameter -- |
| ------------------------- |
| |
| function Is_Actual_Parameter return Boolean is |
| begin |
| if Nkind (N) = N_Identifier then |
| case Nkind (Parent (N)) is |
| when N_Procedure_Call_Statement => |
| return Is_List_Member (N) |
| and then List_Containing (N) = |
| Parameter_Associations (Parent (N)); |
| |
| when N_Parameter_Association => |
| return N = Explicit_Actual_Parameter (Parent (N)) |
| and then Nkind (Parent (Parent (N))) = |
| N_Procedure_Call_Statement; |
| |
| when others => |
| return False; |
| end case; |
| else |
| return False; |
| end if; |
| end Is_Actual_Parameter; |
| |
| ------------------------- |
| -- Known_But_Invisible -- |
| ------------------------- |
| |
| function Known_But_Invisible (E : Entity_Id) return Boolean is |
| Fname : File_Name_Type; |
| |
| begin |
| -- Entities in Standard are always considered to be known |
| |
| if Sloc (E) <= Standard_Location then |
| return True; |
| |
| -- An entity that does not come from source is always considered |
| -- to be unknown, since it is an artifact of code expansion. |
| |
| elsif not Comes_From_Source (E) then |
| return False; |
| end if; |
| |
| -- Here we have an entity that is not from package Standard, and |
| -- which comes from Source. See if it comes from an internal file. |
| |
| Fname := Unit_File_Name (Get_Source_Unit (E)); |
| |
| -- Case of from internal file |
| |
| if In_Internal_Unit (E) then |
| |
| -- Private part entities in internal files are never considered |
| -- to be known to the writer of normal application code. |
| |
| if Is_Hidden (E) then |
| return False; |
| end if; |
| |
| -- Entities from System packages other than System and |
| -- System.Storage_Elements are not considered to be known. |
| -- System.Auxxxx files are also considered known to the user. |
| |
| -- Should refine this at some point to generally distinguish |
| -- between known and unknown internal files ??? |
| |
| Get_Name_String (Fname); |
| |
| return |
| Name_Len < 2 |
| or else |
| Name_Buffer (1 .. 2) /= "s-" |
| or else |
| Name_Buffer (3 .. 8) = "stoele" |
| or else |
| Name_Buffer (3 .. 5) = "aux"; |
| |
| -- If not an internal file, then entity is definitely known, even if |
| -- it is in a private part (the message generated will note that it |
| -- is in a private part). |
| |
| else |
| return True; |
| end if; |
| end Known_But_Invisible; |
| |
| ------------------- |
| -- Nvis_Messages -- |
| ------------------- |
| |
| procedure Nvis_Messages is |
| Comp_Unit : Node_Id; |
| Ent : Entity_Id; |
| Found : Boolean := False; |
| Hidden : Boolean := False; |
| Item : Node_Id; |
| |
| begin |
| -- Ada 2005 (AI-262): Generate a precise error concerning the |
| -- Beaujolais effect that was previously detected |
| |
| if Nvis_Is_Private_Subprg then |
| |
| pragma Assert (Nkind (E2) = N_Defining_Identifier |
| and then Ekind (E2) = E_Function |
| and then Scope (E2) = Standard_Standard |
| and then Has_Private_With (E2)); |
| |
| -- Find the sloc corresponding to the private with'ed unit |
| |
| Comp_Unit := Cunit (Current_Sem_Unit); |
| Error_Msg_Sloc := No_Location; |
| |
| Item := First (Context_Items (Comp_Unit)); |
| while Present (Item) loop |
| if Nkind (Item) = N_With_Clause |
| and then Private_Present (Item) |
| and then Entity (Name (Item)) = E2 |
| then |
| Error_Msg_Sloc := Sloc (Item); |
| exit; |
| end if; |
| |
| Next (Item); |
| end loop; |
| |
| pragma Assert (Error_Msg_Sloc /= No_Location); |
| |
| Error_Msg_N ("(Ada 2005): hidden by private with clause #", N); |
| return; |
| end if; |
| |
| Undefined (Nvis => True); |
| |
| if Msg then |
| |
| -- First loop does hidden declarations |
| |
| Ent := Homonyms; |
| while Present (Ent) loop |
| if Is_Potentially_Use_Visible (Ent) then |
| if not Hidden then |
| Error_Msg_N -- CODEFIX |
| ("multiple use clauses cause hiding!", N); |
| Hidden := True; |
| end if; |
| |
| Error_Msg_Sloc := Sloc (Ent); |
| Error_Msg_N -- CODEFIX |
| ("hidden declaration#!", N); |
| end if; |
| |
| Ent := Homonym (Ent); |
| end loop; |
| |
| -- If we found hidden declarations, then that's enough, don't |
| -- bother looking for non-visible declarations as well. |
| |
| if Hidden then |
| return; |
| end if; |
| |
| -- Second loop does non-directly visible declarations |
| |
| Ent := Homonyms; |
| while Present (Ent) loop |
| if not Is_Potentially_Use_Visible (Ent) then |
| |
| -- Do not bother the user with unknown entities |
| |
| if not Known_But_Invisible (Ent) then |
| goto Continue; |
| end if; |
| |
| Error_Msg_Sloc := Sloc (Ent); |
| |
| -- Output message noting that there is a non-visible |
| -- declaration, distinguishing the private part case. |
| |
| if Is_Hidden (Ent) then |
| Error_Msg_N ("non-visible (private) declaration#!", N); |
| |
| -- If the entity is declared in a generic package, it |
| -- cannot be visible, so there is no point in adding it |
| -- to the list of candidates if another homograph from a |
| -- non-generic package has been seen. |
| |
| elsif Ekind (Scope (Ent)) = E_Generic_Package |
| and then Found |
| then |
| null; |
| |
| else |
| -- When the entity comes from a generic instance the |
| -- normal error message machinery will give the line |
| -- number of the generic package and the location of |
| -- the generic instance, but not the name of the |
| -- the instance. |
| |
| -- So, in order to give more descriptive error messages |
| -- in this case, we include the name of the generic |
| -- package. |
| |
| if Is_Generic_Instance (Scope (Ent)) then |
| Error_Msg_Name_1 := Chars (Scope (Ent)); |
| Error_Msg_N -- CODEFIX |
| ("non-visible declaration from %#!", N); |
| |
| -- Otherwise print the message normally |
| |
| else |
| Error_Msg_N -- CODEFIX |
| ("non-visible declaration#!", N); |
| end if; |
| |
| if Ekind (Scope (Ent)) /= E_Generic_Package then |
| Found := True; |
| end if; |
| |
| if Is_Compilation_Unit (Ent) |
| and then |
| Nkind (Parent (Parent (N))) = N_Use_Package_Clause |
| then |
| Error_Msg_Qual_Level := 99; |
| Error_Msg_NE -- CODEFIX |
| ("\\missing `WITH &;`", N, Ent); |
| Error_Msg_Qual_Level := 0; |
| end if; |
| |
| if Ekind (Ent) = E_Discriminant |
| and then Present (Corresponding_Discriminant (Ent)) |
| and then Scope (Corresponding_Discriminant (Ent)) = |
| Etype (Scope (Ent)) |
| then |
| Error_Msg_N |
| ("inherited discriminant not allowed here" & |
| " (RM 3.8 (12), 3.8.1 (6))!", N); |
| end if; |
| end if; |
| |
| -- Set entity and its containing package as referenced. We |
| -- can't be sure of this, but this seems a better choice |
| -- to avoid unused entity messages. |
| |
| if Comes_From_Source (Ent) then |
| Set_Referenced (Ent); |
| Set_Referenced (Cunit_Entity (Get_Source_Unit (Ent))); |
| end if; |
| end if; |
| |
| <<Continue>> |
| Ent := Homonym (Ent); |
| end loop; |
| end if; |
| end Nvis_Messages; |
| |
| --------------- |
| -- Undefined -- |
| --------------- |
| |
| procedure Undefined (Nvis : Boolean) is |
| Emsg : Error_Msg_Id; |
| |
| begin |
| -- We should never find an undefined internal name. If we do, then |
| -- see if we have previous errors. If so, ignore on the grounds that |
| -- it is probably a cascaded message (e.g. a block label from a badly |
| -- formed block). If no previous errors, then we have a real internal |
| -- error of some kind so raise an exception. |
| |
| if Is_Internal_Name (Chars (N)) then |
| if Total_Errors_Detected /= 0 then |
| return; |
| else |
| raise Program_Error; |
| end if; |
| end if; |
| |
| -- A very specialized error check, if the undefined variable is |
| -- a case tag, and the case type is an enumeration type, check |
| -- for a possible misspelling, and if so, modify the identifier |
| |
| -- Named aggregate should also be handled similarly ??? |
| |
| if Nkind (N) = N_Identifier |
| and then Nkind (Parent (N)) = N_Case_Statement_Alternative |
| then |
| declare |
| Case_Stm : constant Node_Id := Parent (Parent (N)); |
| Case_Typ : constant Entity_Id := Etype (Expression (Case_Stm)); |
| |
| Lit : Node_Id; |
| |
| begin |
| if Is_Enumeration_Type (Case_Typ) |
| and then not Is_Standard_Character_Type (Case_Typ) |
| then |
| Lit := First_Literal (Case_Typ); |
| Get_Name_String (Chars (Lit)); |
| |
| if Chars (Lit) /= Chars (N) |
| and then Is_Bad_Spelling_Of (Chars (N), Chars (Lit)) |
| then |
| Error_Msg_Node_2 := Lit; |
| Error_Msg_N -- CODEFIX |
| ("& is undefined, assume misspelling of &", N); |
| Rewrite (N, New_Occurrence_Of (Lit, Sloc (N))); |
| return; |
| end if; |
| |
| Next_Literal (Lit); |
| end if; |
| end; |
| end if; |
| |
| -- Normal processing |
| |
| Set_Entity (N, Any_Id); |
| Set_Etype (N, Any_Type); |
| |
| -- We use the table Urefs to keep track of entities for which we |
| -- have issued errors for undefined references. Multiple errors |
| -- for a single name are normally suppressed, however we modify |
| -- the error message to alert the programmer to this effect. |
| |
| for J in Urefs.First .. Urefs.Last loop |
| if Chars (N) = Chars (Urefs.Table (J).Node) then |
| if Urefs.Table (J).Err /= No_Error_Msg |
| and then Sloc (N) /= Urefs.Table (J).Loc |
| then |
| Error_Msg_Node_1 := Urefs.Table (J).Node; |
| |
| if Urefs.Table (J).Nvis then |
| Change_Error_Text (Urefs.Table (J).Err, |
| "& is not visible (more references follow)"); |
| else |
| Change_Error_Text (Urefs.Table (J).Err, |
| "& is undefined (more references follow)"); |
| end if; |
| |
| Urefs.Table (J).Err := No_Error_Msg; |
| end if; |
| |
| -- Although we will set Msg False, and thus suppress the |
| -- message, we also set Error_Posted True, to avoid any |
| -- cascaded messages resulting from the undefined reference. |
| |
| Msg := False; |
| Set_Error_Posted (N); |
| return; |
| end if; |
| end loop; |
| |
| -- If entry not found, this is first undefined occurrence |
| |
| if Nvis then |
| Error_Msg_N ("& is not visible!", N); |
| Emsg := Get_Msg_Id; |
| |
| else |
| Error_Msg_N ("& is undefined!", N); |
| Emsg := Get_Msg_Id; |
| |
| -- A very bizarre special check, if the undefined identifier |
| -- is Put or Put_Line, then add a special error message (since |
| -- this is a very common error for beginners to make). |
| |
| if Chars (N) in Name_Put | Name_Put_Line then |
| Error_Msg_N -- CODEFIX |
| ("\\possible missing `WITH Ada.Text_'I'O; " & |
| "USE Ada.Text_'I'O`!", N); |
| |
| -- Another special check if N is the prefix of a selected |
| -- component which is a known unit: add message complaining |
| -- about missing with for this unit. |
| |
| elsif Nkind (Parent (N)) = N_Selected_Component |
| and then N = Prefix (Parent (N)) |
| and then Is_Known_Unit (Parent (N)) |
| then |
| Error_Missing_With_Of_Known_Unit (N); |
| end if; |
| |
| -- Now check for possible misspellings |
| |
| declare |
| E : Entity_Id; |
| Ematch : Entity_Id := Empty; |
| begin |
| for Nam in First_Name_Id .. Last_Name_Id loop |
| E := Get_Name_Entity_Id (Nam); |
| |
| if Present (E) |
| and then (Is_Immediately_Visible (E) |
| or else |
| Is_Potentially_Use_Visible (E)) |
| then |
| if Is_Bad_Spelling_Of (Chars (N), Nam) then |
| Ematch := E; |
| exit; |
| end if; |
| end if; |
| end loop; |
| |
| if Present (Ematch) then |
| Error_Msg_NE -- CODEFIX |
| ("\possible misspelling of&", N, Ematch); |
| end if; |
| end; |
| end if; |
| |
| -- Make entry in undefined references table unless the full errors |
| -- switch is set, in which case by refraining from generating the |
| -- table entry we guarantee that we get an error message for every |
| -- undefined reference. The entry is not added if we are ignoring |
| -- errors. |
| |
| if not All_Errors_Mode |
| and then Ignore_Errors_Enable = 0 |
| and then not Get_Ignore_Errors |
| then |
| Urefs.Append ( |
| (Node => N, |
| Err => Emsg, |
| Nvis => Nvis, |
| Loc => Sloc (N))); |
| end if; |
| |
| Msg := True; |
| end Undefined; |
| |
| -- Local variables |
| |
| Nested_Inst : Entity_Id := Empty; |
| -- The entity of a nested instance which appears within Inst (if any) |
| |
| -- Start of processing for Find_Direct_Name |
| |
| begin |
| -- If the entity pointer is already set, this is an internal node, or |
| -- a node that is analyzed more than once, after a tree modification. |
| -- In such a case there is no resolution to perform, just set the type. |
| |
| if Present (Entity (N)) then |
| if Is_Type (Entity (N)) then |
| Set_Etype (N, Entity (N)); |
| |
| -- The exception to this general rule are constants associated with |
| -- discriminals of protected types because for each protected op |
| -- a new set of discriminals is internally created by the frontend |
| -- (see Exp_Ch9.Set_Discriminals), and the current decoration of the |
| -- entity pointer may have been set as part of a preanalysis, where |
| -- discriminals still reference the first subprogram or entry to be |
| -- expanded (see Expand_Protected_Body_Declarations). |
| |
| elsif Full_Analysis |
| and then Ekind (Entity (N)) = E_Constant |
| and then Present (Discriminal_Link (Entity (N))) |
| and then Is_Protected_Type (Scope (Discriminal_Link (Entity (N)))) |
| then |
| goto Find_Name; |
| |
| else |
| declare |
| Entyp : constant Entity_Id := Etype (Entity (N)); |
| |
| begin |
| -- One special case here. If the Etype field is already set, |
| -- and references the packed array type corresponding to the |
| -- etype of the referenced entity, then leave it alone. This |
| -- happens for trees generated from Exp_Pakd, where expressions |
| -- can be deliberately "mis-typed" to the packed array type. |
| |
| if Is_Packed_Array (Entyp) |
| and then Present (Etype (N)) |
| and then Etype (N) = Packed_Array_Impl_Type (Entyp) |
| then |
| null; |
| |
| -- If not that special case, then just reset the Etype |
| |
| else |
| Set_Etype (N, Entyp); |
| end if; |
| end; |
| end if; |
| |
| -- Although the marking of use clauses happens at the end of |
| -- Find_Direct_Name, a certain case where a generic actual satisfies |
| -- a use clause must be checked here due to how the generic machinery |
| -- handles the analysis of said actuals. |
| |
| if In_Instance |
| and then Nkind (Parent (N)) = N_Generic_Association |
| then |
| Mark_Use_Clauses (Entity (N)); |
| end if; |
| |
| return; |
| end if; |
| |
| <<Find_Name>> |
| |
| -- Preserve relevant elaboration-related attributes of the context which |
| -- are no longer available or very expensive to recompute once analysis, |
| -- resolution, and expansion are over. |
| |
| if Nkind (N) = N_Identifier then |
| Mark_Elaboration_Attributes |
| (N_Id => N, |
| Checks => True, |
| Modes => True, |
| Warnings => True); |
| end if; |
| |
| -- Here if Entity pointer was not set, we need full visibility analysis |
| -- First we generate debugging output if the debug E flag is set. |
| |
| if Debug_Flag_E then |
| Write_Str ("Looking for "); |
| Write_Name (Chars (N)); |
| Write_Eol; |
| end if; |
| |
| Homonyms := Current_Entity (N); |
| Nvis_Entity := False; |
| |
| E := Homonyms; |
| while Present (E) loop |
| |
| -- If entity is immediately visible or potentially use visible, then |
| -- process the entity and we are done. |
| |
| if Is_Immediately_Visible (E) then |
| goto Immediately_Visible_Entity; |
| |
| elsif Is_Potentially_Use_Visible (E) then |
| goto Potentially_Use_Visible_Entity; |
| |
| -- Note if a known but invisible entity encountered |
| |
| elsif Known_But_Invisible (E) then |
| Nvis_Entity := True; |
| end if; |
| |
| -- Move to next entity in chain and continue search |
| |
| E := Homonym (E); |
| end loop; |
| |
| -- If no entries on homonym chain that were potentially visible, |
| -- and no entities reasonably considered as non-visible, then |
| -- we have a plain undefined reference, with no additional |
| -- explanation required. |
| |
| if not Nvis_Entity then |
| Undefined (Nvis => False); |
| |
| -- Otherwise there is at least one entry on the homonym chain that |
| -- is reasonably considered as being known and non-visible. |
| |
| else |
| Nvis_Messages; |
| end if; |
| |
| goto Done; |
| |
| -- Processing for a potentially use visible entry found. We must search |
| -- the rest of the homonym chain for two reasons. First, if there is a |
| -- directly visible entry, then none of the potentially use-visible |
| -- entities are directly visible (RM 8.4(10)). Second, we need to check |
| -- for the case of multiple potentially use-visible entries hiding one |
| -- another and as a result being non-directly visible (RM 8.4(11)). |
| |
| <<Potentially_Use_Visible_Entity>> declare |
| Only_One_Visible : Boolean := True; |
| All_Overloadable : Boolean := Is_Overloadable (E); |
| |
| begin |
| E2 := Homonym (E); |
| while Present (E2) loop |
| if Is_Immediately_Visible (E2) then |
| |
| -- If the use-visible entity comes from the actual for a |
| -- formal package, it hides a directly visible entity from |
| -- outside the instance. |
| |
| if From_Actual_Package (E) |
| and then Scope_Depth (Scope (E2)) < Scope_Depth (Inst) |
| then |
| goto Found; |
| else |
| E := E2; |
| goto Immediately_Visible_Entity; |
| end if; |
| |
| elsif Is_Potentially_Use_Visible (E2) then |
| Only_One_Visible := False; |
| All_Overloadable := All_Overloadable and Is_Overloadable (E2); |
| |
| -- Ada 2005 (AI-262): Protect against a form of Beaujolais effect |
| -- that can occur in private_with clauses. Example: |
| |
| -- with A; |
| -- private with B; package A is |
| -- package C is function B return Integer; |
| -- use A; end A; |
| -- V1 : Integer := B; |
| -- private function B return Integer; |
| -- V2 : Integer := B; |
| -- end C; |
| |
| -- V1 resolves to A.B, but V2 resolves to library unit B |
| |
| elsif Ekind (E2) = E_Function |
| and then Scope (E2) = Standard_Standard |
| and then Has_Private_With (E2) |
| then |
| Only_One_Visible := False; |
| All_Overloadable := False; |
| Nvis_Is_Private_Subprg := True; |
| exit; |
| end if; |
| |
| E2 := Homonym (E2); |
| end loop; |
| |
| -- On falling through this loop, we have checked that there are no |
| -- immediately visible entities. Only_One_Visible is set if exactly |
| -- one potentially use visible entity exists. All_Overloadable is |
| -- set if all the potentially use visible entities are overloadable. |
| -- The condition for legality is that either there is one potentially |
| -- use visible entity, or if there is more than one, then all of them |
| -- are overloadable. |
| |
| if Only_One_Visible or All_Overloadable then |
| goto Found; |
| |
| -- If there is more than one potentially use-visible entity and at |
| -- least one of them non-overloadable, we have an error (RM 8.4(11)). |
| -- Note that E points to the first such entity on the homonym list. |
| |
| else |
| -- If one of the entities is declared in an actual package, it |
| -- was visible in the generic, and takes precedence over other |
| -- entities that are potentially use-visible. The same applies |
| -- if the entity is declared in a local instantiation of the |
| -- current instance. |
| |
| if In_Instance then |
| |
| -- Find the current instance |
| |
| Inst := Current_Scope; |
| while Present (Inst) and then Inst /= Standard_Standard loop |
| if Is_Generic_Instance (Inst) then |
| exit; |
| end if; |
| |
| Inst := Scope (Inst); |
| end loop; |
| |
| -- Reexamine the candidate entities, giving priority to those |
| -- that were visible within the generic. |
| |
| E2 := E; |
| while Present (E2) loop |
| Nested_Inst := Nearest_Enclosing_Instance (E2); |
| |
| -- The entity is declared within an actual package, or in a |
| -- nested instance. The ">=" accounts for the case where the |
| -- current instance and the nested instance are the same. |
| |
| if From_Actual_Package (E2) |
| or else (Present (Nested_Inst) |
| and then Scope_Depth (Nested_Inst) >= |
| Scope_Depth (Inst)) |
| then |
| E := E2; |
| goto Found; |
| end if; |
| |
| E2 := Homonym (E2); |
| end loop; |
| |
| Nvis_Messages; |
| goto Done; |
| |
| elsif Is_Predefined_Unit (Current_Sem_Unit) then |
| -- A use clause in the body of a system file creates conflict |
| -- with some entity in a user scope, while rtsfind is active. |
| -- Keep only the entity coming from another predefined unit. |
| |
| E2 := E; |
| while Present (E2) loop |
| if In_Predefined_Unit (E2) then |
| E := E2; |
| goto Found; |
| end if; |
| |
| E2 := Homonym (E2); |
| end loop; |
| |
| -- Entity must exist because predefined unit is correct |
| |
| raise Program_Error; |
| |
| else |
| Nvis_Messages; |
| goto Done; |
| end if; |
| end if; |
| end; |
| |
| -- Come here with E set to the first immediately visible entity on |
| -- the homonym chain. This is the one we want unless there is another |
| -- immediately visible entity further on in the chain for an inner |
| -- scope (RM 8.3(8)). |
| |
| <<Immediately_Visible_Entity>> declare |
| Level : Int; |
| Scop : Entity_Id; |
| |
| begin |
| -- Find scope level of initial entity. When compiling through |
| -- Rtsfind, the previous context is not completely invisible, and |
| -- an outer entity may appear on the chain, whose scope is below |
| -- the entry for Standard that delimits the current scope stack. |
| -- Indicate that the level for this spurious entry is outside of |
| -- the current scope stack. |
| |
| Level := Scope_Stack.Last; |
| loop |
| Scop := Scope_Stack.Table (Level).Entity; |
| exit when Scop = Scope (E); |
| Level := Level - 1; |
| exit when Scop = Standard_Standard; |
| end loop; |
| |
| -- Now search remainder of homonym chain for more inner entry |
| -- If the entity is Standard itself, it has no scope, and we |
| -- compare it with the stack entry directly. |
| |
| E2 := Homonym (E); |
| while Present (E2) loop |
| if Is_Immediately_Visible (E2) then |
| |
| -- If a generic package contains a local declaration that |
| -- has the same name as the generic, there may be a visibility |
| -- conflict in an instance, where the local declaration must |
| -- also hide the name of the corresponding package renaming. |
| -- We check explicitly for a package declared by a renaming, |
| -- whose renamed entity is an instance that is on the scope |
| -- stack, and that contains a homonym in the same scope. Once |
| -- we have found it, we know that the package renaming is not |
| -- immediately visible, and that the identifier denotes the |
| -- other entity (and its homonyms if overloaded). |
| |
| if Scope (E) = Scope (E2) |
| and then Ekind (E) = E_Package |
| and then Present (Renamed_Entity (E)) |
| and then Is_Generic_Instance (Renamed_Entity (E)) |
| and then In_Open_Scopes (Renamed_Entity (E)) |
| and then Comes_From_Source (N) |
| then |
| Set_Is_Immediately_Visible (E, False); |
| E := E2; |
| |
| else |
| for J in Level + 1 .. Scope_Stack.Last loop |
| if Scope_Stack.Table (J).Entity = Scope (E2) |
| or else Scope_Stack.Table (J).Entity = E2 |
| then |
| Level := J; |
| E := E2; |
| exit; |
| end if; |
| end loop; |
| end if; |
| end if; |
| |
| E2 := Homonym (E2); |
| end loop; |
| |
| -- At the end of that loop, E is the innermost immediately |
| -- visible entity, so we are all set. |
| end; |
| |
| -- Come here with entity found, and stored in E |
| |
| <<Found>> begin |
| |
| -- Check violation of No_Wide_Characters restriction |
| |
| Check_Wide_Character_Restriction (E, N); |
| |
| -- When distribution features are available (Get_PCS_Name /= |
| -- Name_No_DSA), a remote access-to-subprogram type is converted |
| -- into a record type holding whatever information is needed to |
| -- perform a remote call on an RCI subprogram. In that case we |
| -- rewrite any occurrence of the RAS type into the equivalent record |
| -- type here. 'Access attribute references and RAS dereferences are |
| -- then implemented using specific TSSs. However when distribution is |
| -- not available (case of Get_PCS_Name = Name_No_DSA), we bypass the |
| -- generation of these TSSs, and we must keep the RAS type in its |
| -- original access-to-subprogram form (since all calls through a |
| -- value of such type will be local anyway in the absence of a PCS). |
| |
| if Comes_From_Source (N) |
| and then Is_Remote_Access_To_Subprogram_Type (E) |
| and then Ekind (E) = E_Access_Subprogram_Type |
| and then Expander_Active |
| and then Get_PCS_Name /= Name_No_DSA |
| then |
| Rewrite (N, New_Occurrence_Of (Equivalent_Type (E), Sloc (N))); |
| goto Done; |
| end if; |
| |
| -- Set the entity. Note that the reason we call Set_Entity for the |
| -- overloadable case, as opposed to Set_Entity_With_Checks is |
| -- that in the overloaded case, the initial call can set the wrong |
| -- homonym. The call that sets the right homonym is in Sem_Res and |
| -- that call does use Set_Entity_With_Checks, so we don't miss |
| -- a style check. |
| |
| if Is_Overloadable (E) then |
| Set_Entity (N, E); |
| else |
| Set_Entity_With_Checks (N, E); |
| end if; |
| |
| if Is_Type (E) then |
| Set_Etype (N, E); |
| else |
| Set_Etype (N, Get_Full_View (Etype (E))); |
| end if; |
| |
| if Debug_Flag_E then |
| Write_Str (" found "); |
| Write_Entity_Info (E, " "); |
| end if; |
| |
| -- If the Ekind of the entity is Void, it means that all homonyms |
| -- are hidden from all visibility (RM 8.3(5,14-20)). However, this |
| -- test is skipped if the current scope is a record and the name is |
| -- a pragma argument expression (case of Atomic and Volatile pragmas |
| -- and possibly other similar pragmas added later, which are allowed |
| -- to reference components in the current record). |
| |
| if Ekind (E) = E_Void |
| and then |
| (not Is_Record_Type (Current_Scope) |
| or else Nkind (Parent (N)) /= N_Pragma_Argument_Association) |
| then |
| Premature_Usage (N); |
| |
| -- If the entity is overloadable, collect all interpretations of the |
| -- name for subsequent overload resolution. We optimize a bit here to |
| -- do this only if we have an overloadable entity that is not on its |
| -- own on the homonym chain. |
| |
| elsif Is_Overloadable (E) |
| and then (Present (Homonym (E)) or else Current_Entity (N) /= E) |
| then |
| Collect_Interps (N); |
| |
| -- If no homonyms were visible, the entity is unambiguous |
| |
| if not Is_Overloaded (N) then |
| if not Is_Actual_Parameter then |
| Generate_Reference (E, N); |
| end if; |
| end if; |
| |
| -- Case of non-overloadable entity, set the entity providing that |
| -- we do not have the case of a discriminant reference within a |
| -- default expression. Such references are replaced with the |
| -- corresponding discriminal, which is the formal corresponding to |
| -- to the discriminant in the initialization procedure. |
| |
| else |
| -- Entity is unambiguous, indicate that it is referenced here |
| |
| -- For a renaming of an object, always generate simple reference, |
| -- we don't try to keep track of assignments in this case, except |
| -- in SPARK mode where renamings are traversed for generating |
| -- local effects of subprograms. |
| |
| if Is_Object (E) |
| and then Present (Renamed_Object (E)) |
| and then not GNATprove_Mode |
| then |
| Generate_Reference (E, N); |
| |
| -- If the renamed entity is a private protected component, |
| -- reference the original component as well. This needs to be |
| -- done because the private renamings are installed before any |
| -- analysis has occurred. Reference to a private component will |
| -- resolve to the renaming and the original component will be |
| -- left unreferenced, hence the following. |
| |
| if Is_Prival (E) then |
| Generate_Reference (Prival_Link (E), N); |
| end if; |
| |
| -- One odd case is that we do not want to set the Referenced flag |
| -- if the entity is a label, and the identifier is the label in |
| -- the source, since this is not a reference from the point of |
| -- view of the user. |
| |
| elsif Nkind (Parent (N)) = N_Label then |
| declare |
| R : constant Boolean := Referenced (E); |
| |
| begin |
| -- Generate reference unless this is an actual parameter |
| -- (see comment below). |
| |
| if not Is_Actual_Parameter then |
| Generate_Reference (E, N); |
| Set_Referenced (E, R); |
| end if; |
| end; |
| |
| -- Normal case, not a label: generate reference |
| |
| else |
| if not Is_Actual_Parameter then |
| |
| -- Package or generic package is always a simple reference |
| |
| if Is_Package_Or_Generic_Package (E) then |
| Generate_Reference (E, N, 'r'); |
| |
| -- Else see if we have a left hand side |
| |
| else |
| case Known_To_Be_Assigned (N, Only_LHS => True) is |
| when True => |
| Generate_Reference (E, N, 'm'); |
| |
| when False => |
| Generate_Reference (E, N, 'r'); |
| |
| end case; |
| end if; |
| end if; |
| end if; |
| |
| Set_Entity_Or_Discriminal (N, E); |
| |
| -- The name may designate a generalized reference, in which case |
| -- the dereference interpretation will be included. Context is |
| -- one in which a name is legal. |
| |
| if Ada_Version >= Ada_2012 |
| and then |
| (Nkind (Parent (N)) in N_Subexpr |
| or else Nkind (Parent (N)) in N_Assignment_Statement |
| | N_Object_Declaration |
| | N_Parameter_Association) |
| then |
| Check_Implicit_Dereference (N, Etype (E)); |
| end if; |
| end if; |
| end; |
| |
| -- Mark relevant use-type and use-package clauses as effective if the |
| -- node in question is not overloaded and therefore does not require |
| -- resolution. |
| -- |
| -- Note: Generic actual subprograms do not follow the normal resolution |
| -- path, so ignore the fact that they are overloaded and mark them |
| -- anyway. |
| |
| if Nkind (N) not in N_Subexpr or else not Is_Overloaded (N) then |
| Mark_Use_Clauses (N); |
| end if; |
| |
| -- Come here with entity set |
| |
| <<Done>> |
| Check_Restriction_No_Use_Of_Entity (N); |
| |
| -- Annotate the tree by creating a variable reference marker in case the |
| -- original variable reference is folded or optimized away. The variable |
| -- reference marker is automatically saved for later examination by the |
| -- ABE Processing phase. Variable references which act as actuals in a |
| -- call require special processing and are left to Resolve_Actuals. The |
| -- reference is a write when it appears on the left hand side of an |
| -- assignment. |
| |
| if Needs_Variable_Reference_Marker (N => N, Calls_OK => False) then |
| declare |
| Is_Assignment_LHS : constant Boolean := Known_To_Be_Assigned (N); |
| |
| begin |
| Build_Variable_Reference_Marker |
| (N => N, |
| Read => not Is_Assignment_LHS, |
| Write => Is_Assignment_LHS); |
| end; |
| end if; |
| end Find_Direct_Name; |
| |
| ------------------------ |
| -- Find_Expanded_Name -- |
| ------------------------ |
| |
| -- This routine searches the homonym chain of the entity until it finds |
| -- an entity declared in the scope denoted by the prefix. If the entity |
| -- is private, it may nevertheless be immediately visible, if we are in |
| -- the scope of its declaration. |
| |
| procedure Find_Expanded_Name (N : Node_Id) is |
| function In_Abstract_View_Pragma (Nod : Node_Id) return Boolean; |
| -- Determine whether expanded name Nod appears within a pragma which is |
| -- a suitable context for an abstract view of a state or variable. The |
| -- following pragmas fall in this category: |
| -- Depends |
| -- Global |
| -- Initializes |
| -- Refined_Depends |
| -- Refined_Global |
| -- |
| -- In addition, pragma Abstract_State is also considered suitable even |
| -- though it is an illegal context for an abstract view as this allows |
| -- for proper resolution of abstract views of variables. This illegal |
| -- context is later flagged in the analysis of indicator Part_Of. |
| |
| ----------------------------- |
| -- In_Abstract_View_Pragma -- |
| ----------------------------- |
| |
| function In_Abstract_View_Pragma (Nod : Node_Id) return Boolean is |
| Par : Node_Id; |
| |
| begin |
| -- Climb the parent chain looking for a pragma |
| |
| Par := Nod; |
| while Present (Par) loop |
| if Nkind (Par) = N_Pragma then |
| if Pragma_Name_Unmapped (Par) |
| in Name_Abstract_State |
| | Name_Depends |
| | Name_Global |
| | Name_Initializes |
| | Name_Refined_Depends |
| | Name_Refined_Global |
| then |
| return True; |
| |
| -- Otherwise the pragma is not a legal context for an abstract |
| -- view. |
| |
| else |
| exit; |
| end if; |
| |
| -- Prevent the search from going too far |
| |
| elsif Is_Body_Or_Package_Declaration (Par) then |
| exit; |
| end if; |
| |
| Par := Parent (Par); |
| end loop; |
| |
| return False; |
| end In_Abstract_View_Pragma; |
| |
| -- Local variables |
| |
| Selector : constant Node_Id := Selector_Name (N); |
| |
| Candidate : Entity_Id := Empty; |
| P_Name : Entity_Id; |
| Id : Entity_Id; |
| |
| -- Start of processing for Find_Expanded_Name |
| |
| begin |
| P_Name := Entity (Prefix (N)); |
| |
| -- If the prefix is a renamed package, look for the entity in the |
| -- original package. |
| |
| if Ekind (P_Name) = E_Package |
| and then Present (Renamed_Entity (P_Name)) |
| then |
| P_Name := Renamed_Entity (P_Name); |
| |
| if From_Limited_With (P_Name) |
| and then not Unit_Is_Visible (Cunit (Get_Source_Unit (P_Name))) |
| then |
| Error_Msg_NE |
| ("renaming of limited view of package & not usable in this" |
| & " context (RM 8.5.3(3.1/2))", Prefix (N), P_Name); |
| |
| elsif Has_Limited_View (P_Name) |
| and then not Unit_Is_Visible (Cunit (Get_Source_Unit (P_Name))) |
| and then not Is_Visible_Through_Renamings (P_Name) |
| then |
| Error_Msg_NE |
| ("renaming of limited view of package & not usable in this" |
| & " context (RM 8.5.3(3.1/2))", Prefix (N), P_Name); |
| end if; |
| |
| -- Rewrite node with entity field pointing to renamed object |
| |
| Rewrite (Prefix (N), New_Copy (Prefix (N))); |
| Set_Entity (Prefix (N), P_Name); |
| |
| -- If the prefix is an object of a concurrent type, look for |
| -- the entity in the associated task or protected type. |
| |
| elsif Is_Concurrent_Type (Etype (P_Name)) then |
| P_Name := Etype (P_Name); |
| end if; |
| |
| Id := Current_Entity (Selector); |
| |
| declare |
| Is_New_Candidate : Boolean; |
| |
| begin |
| while Present (Id) loop |
| if Scope (Id) = P_Name then |
| Candidate := Id; |
| Is_New_Candidate := True; |
| |
| -- Handle abstract views of states and variables. These are |
| -- acceptable candidates only when the reference to the view |
| -- appears in certain pragmas. |
| |
| if Ekind (Id) = E_Abstract_State |
| and then From_Limited_With (Id) |
| and then Present (Non_Limited_View (Id)) |
| then |
| if In_Abstract_View_Pragma (N) then |
| Candidate := Non_Limited_View (Id); |
| Is_New_Candidate := True; |
| |
| -- Hide the candidate because it is not used in a proper |
| -- context. |
| |
| else |
| Candidate := Empty; |
| Is_New_Candidate := False; |
| end if; |
| end if; |
| |
| -- Ada 2005 (AI-217): Handle shadow entities associated with |
| -- types declared in limited-withed nested packages. We don't need |
| -- to handle E_Incomplete_Subtype entities because the entities |
| -- in the limited view are always E_Incomplete_Type and |
| -- E_Class_Wide_Type entities (see Build_Limited_Views). |
| |
| -- Regarding the expression used to evaluate the scope, it |
| -- is important to note that the limited view also has shadow |
| -- entities associated nested packages. For this reason the |
| -- correct scope of the entity is the scope of the real entity. |
| -- The non-limited view may itself be incomplete, in which case |
| -- get the full view if available. |
| |
| elsif Ekind (Id) in E_Incomplete_Type | E_Class_Wide_Type |
| and then From_Limited_With (Id) |
| and then Present (Non_Limited_View (Id)) |
| and then Scope (Non_Limited_View (Id)) = P_Name |
| then |
| Candidate := Get_Full_View (Non_Limited_View (Id)); |
| Is_New_Candidate := True; |
| |
| -- Handle special case where the prefix is a renaming of a shadow |
| -- package which is visible. Required to avoid reporting spurious |
| -- errors. |
| |
| elsif Ekind (P_Name) = E_Package |
| and then From_Limited_With (P_Name) |
| and then not From_Limited_With (Id) |
| and then Sloc (Scope (Id)) = Sloc (P_Name) |
| and then Unit_Is_Visible (Cunit (Get_Source_Unit (P_Name))) |
| then |
| Candidate := Get_Full_View (Id); |
| Is_New_Candidate := True; |
| |
| -- An unusual case arises with a fully qualified name for an |
| -- entity local to a generic child unit package, within an |
| -- instantiation of that package. The name of the unit now |
| -- denotes the renaming created within the instance. This is |
| -- only relevant in an instance body, see below. |
| |
| elsif Is_Generic_Instance (Scope (Id)) |
| and then In_Open_Scopes (Scope (Id)) |
| and then In_Instance_Body |
| and then Ekind (Scope (Id)) = E_Package |
| and then Ekind (Id) = E_Package |
| and then Renamed_Entity (Id) = Scope (Id) |
| and then Is_Immediately_Visible (P_Name) |
| then |
| Is_New_Candidate := True; |
| |
| else |
| Is_New_Candidate := False; |
| end if; |
| |
| if Is_New_Candidate then |
| |
| -- If entity is a child unit, either it is a visible child of |
| -- the prefix, or we are in the body of a generic prefix, as |
| -- will happen when a child unit is instantiated in the body |
| -- of a generic parent. This is because the instance body does |
| -- not restore the full compilation context, given that all |
| -- non-local references have been captured. |
| |
| if Is_Child_Unit (Id) or else P_Name = Standard_Standard then |
| exit when Is_Visible_Lib_Unit (Id) |
| or else (Is_Child_Unit (Id) |
| and then In_Open_Scopes (Scope (Id)) |
| and then In_Instance_Body); |
| else |
| exit when not Is_Hidden (Id); |
| end if; |
| |
| exit when Is_Immediately_Visible (Id); |
| end if; |
| |
| Id := Homonym (Id); |
| end loop; |
| end; |
| |
| if No (Id) |
| and then Ekind (P_Name) in E_Procedure | E_Function |
| and then Is_Generic_Instance (P_Name) |
| then |
| -- Expanded name denotes entity in (instance of) generic subprogram. |
| -- The entity may be in the subprogram instance, or may denote one of |
| -- the formals, which is declared in the enclosing wrapper package. |
| |
| P_Name := Scope (P_Name); |
| |
| Id := Current_Entity (Selector); |
| while Present (Id) loop |
| exit when Scope (Id) = P_Name; |
| Id := Homonym (Id); |
| end loop; |
| end if; |
| |
| if No (Id) or else Chars (Id) /= Chars (Selector) then |
| Set_Etype (N, Any_Type); |
| |
| -- If we are looking for an entity defined in System, try to find it |
| -- in the child package that may have been provided as an extension |
| -- to System. The Extend_System pragma will have supplied the name of |
| -- the extension, which may have to be loaded. |
| |
| if Chars (P_Name) = Name_System |
| and then Scope (P_Name) = Standard_Standard |
| and then Present (System_Extend_Unit) |
| and then Present_System_Aux (N) |
| then |
| Set_Entity (Prefix (N), System_Aux_Id); |
| Find_Expanded_Name (N); |
| return; |
| |
| -- There is an implicit instance of the predefined operator in |
| -- the given scope. The operator entity is defined in Standard. |
| -- Has_Implicit_Operator makes the node into an Expanded_Name. |
| |
| elsif Nkind (Selector) = N_Operator_Symbol |
| and then Has_Implicit_Operator (N) |
| then |
| return; |
| |
| -- If there is no literal defined in the scope denoted by the |
| -- prefix, the literal may belong to (a type derived from) |
| -- Standard_Character, for which we have no explicit literals. |
| |
| elsif Nkind (Selector) = N_Character_Literal |
| and then Has_Implicit_Character_Literal (N) |
| then |
| return; |
| |
| else |
| -- If the prefix is a single concurrent object, use its name in |
| -- the error message, rather than that of the anonymous type. |
| |
| if Is_Concurrent_Type (P_Name) |
| and then Is_Internal_Name (Chars (P_Name)) |
| then |
| Error_Msg_Node_2 := Entity (Prefix (N)); |
| else |
| Error_Msg_Node_2 := P_Name; |
| end if; |
| |
| if P_Name = System_Aux_Id then |
| P_Name := Scope (P_Name); |
| Set_Entity (Prefix (N), P_Name); |
| end if; |
| |
| if Present (Candidate) then |
| |
| -- If we know that the unit is a child unit we can give a more |
| -- accurate error message. |
| |
| if Is_Child_Unit (Candidate) then |
| |
| -- If the candidate is a private child unit and we are in |
| -- the visible part of a public unit, specialize the error |
| -- message. There might be a private with_clause for it, |
| -- but it is not currently active. |
| |
| if Is_Private_Descendant (Candidate) |
| and then Ekind (Current_Scope) = E_Package |
| and then not In_Private_Part (Current_Scope) |
| and then not Is_Private_Descendant (Current_Scope) |
| then |
| Error_Msg_N |
| ("private child unit& is not visible here", Selector); |
| |
| -- Normal case where we have a missing with for a child unit |
| |
| else |
| Error_Msg_Qual_Level := 99; |
| Error_Msg_NE -- CODEFIX |
| ("missing `WITH &;`", Selector, Candidate); |
| Error_Msg_Qual_Level := 0; |
| end if; |
| |
| -- Here we don't know that this is a child unit |
| |
| else |
| Error_Msg_NE ("& is not a visible entity of&", N, Selector); |
| end if; |
| |
| else |
| -- Within the instantiation of a child unit, the prefix may |
| -- denote the parent instance, but the selector has the name |
| -- of the original child. That is to say, when A.B appears |
| -- within an instantiation of generic child unit B, the scope |
| -- stack includes an instance of A (P_Name) and an instance |
| -- of B under some other name. We scan the scope to find this |
| -- child instance, which is the desired entity. |
| -- Note that the parent may itself be a child instance, if |
| -- the reference is of the form A.B.C, in which case A.B has |
| -- already been rewritten with the proper entity. |
| |
| if In_Open_Scopes (P_Name) |
| and then Is_Generic_Instance (P_Name) |
| then |
| declare |
| Gen_Par : constant Entity_Id := |
| Generic_Parent (Specification |
| (Unit_Declaration_Node (P_Name))); |
| S : Entity_Id := Current_Scope; |
| P : Entity_Id; |
| |
| begin |
| for J in reverse 0 .. Scope_Stack.Last loop |
| S := Scope_Stack.Table (J).Entity; |
| |
| exit when S = Standard_Standard; |
| |
| if Ekind (S) in E_Function | E_Package | E_Procedure |
| then |
| P := |
| Generic_Parent (Specification |
| (Unit_Declaration_Node (S))); |
| |
| -- Check that P is a generic child of the generic |
| -- parent of the prefix. |
| |
| if Present (P) |
| and then Chars (P) = Chars (Selector) |
| and then Scope (P) = Gen_Par |
| then |
| Id := S; |
| goto Found; |
| end if; |
| end if; |
| |
| end loop; |
| end; |
| end if; |
| |
| -- If this is a selection from Ada, System or Interfaces, then |
| -- we assume a missing with for the corresponding package. |
| |
| if Is_Known_Unit (N) |
| and then not (Present (Entity (Prefix (N))) |
| and then Scope (Entity (Prefix (N))) /= |
| Standard_Standard) |
| then |
| if not Error_Posted (N) then |
| Error_Msg_NE |
| ("& is not a visible entity of&", Prefix (N), Selector); |
| Error_Missing_With_Of_Known_Unit (Prefix (N)); |
| end if; |
| |
| -- If this is a selection from a dummy package, then suppress |
| -- the error message, of course the entity is missing if the |
| -- package is missing. |
| |
| elsif Sloc (Error_Msg_Node_2) = No_Location then |
| null; |
| |
| -- Here we have the case of an undefined component |
| |
| else |
| -- The prefix may hide a homonym in the context that |
| -- declares the desired entity. This error can use a |
| -- specialized message. |
| |
| if In_Open_Scopes (P_Name) then |
| declare |
| H : constant Entity_Id := Homonym (P_Name); |
| |
| begin |
| if Present (H) |
| and then Is_Compilation_Unit (H) |
| and then |
| (Is_Immediately_Visible (H) |
| or else Is_Visible_Lib_Unit (H)) |
| then |
| Id := First_Entity (H); |
| while Present (Id) loop |
| if Chars (Id) = Chars (Selector) then |
| Error_Msg_Qual_Level := 99; |
| Error_Msg_Name_1 := Chars (Selector); |
| Error_Msg_NE |
| ("% not declared in&", N, P_Name); |
| Error_Msg_NE |
| ("\use fully qualified name starting with " |
| & "Standard to make& visible", N, H); |
| Error_Msg_Qual_Level := 0; |
| goto Done; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| end if; |
| |
| -- If not found, standard error message |
| |
| Error_Msg_NE ("& not declared in&", N, Selector); |
| |
| <<Done>> null; |
| end; |
| |
| else |
| -- Might be worth specializing the case when the prefix |
| -- is a limited view. |
| -- ... not declared in limited view of... |
| |
| Error_Msg_NE ("& not declared in&", N, Selector); |
| end if; |
| |
| -- Check for misspelling of some entity in prefix |
| |
| Id := First_Entity (P_Name); |
| while Present (Id) loop |
| if Is_Bad_Spelling_Of (Chars (Id), Chars (Selector)) |
| and then not Is_Internal_Name (Chars (Id)) |
| then |
| Error_Msg_NE -- CODEFIX |
| ("possible misspelling of&", Selector, Id); |
| exit; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| -- Specialize the message if this may be an instantiation |
| -- of a child unit that was not mentioned in the context. |
| |
| if Nkind (Parent (N)) = N_Package_Instantiation |
| and then Is_Generic_Instance (Entity (Prefix (N))) |
| and then Is_Compilation_Unit |
| (Generic_Parent (Parent (Entity (Prefix (N))))) |
| then |
| Error_Msg_Node_2 := Selector; |
| Error_Msg_N -- CODEFIX |
| ("\missing `WITH &.&;`", Prefix (N)); |
| end if; |
| end if; |
| end if; |
| |
| Id := Any_Id; |
| end if; |
| end if; |
| |
| <<Found>> |
| if Comes_From_Source (N) |
| and then Is_Remote_Access_To_Subprogram_Type (Id) |
| and then Ekind (Id) = E_Access_Subprogram_Type |
| and then Present (Equivalent_Type (Id)) |
| then |
| -- If we are not actually generating distribution code (i.e. the |
| -- current PCS is the dummy non-distributed version), then the |
| -- Equivalent_Type will be missing, and Id should be treated as |
| -- a regular access-to-subprogram type. |
| |
| Id := Equivalent_Type (Id); |
| Set_Chars (Selector, Chars (Id)); |
| end if; |
| |
| -- Ada 2005 (AI-50217): Check usage of entities in limited withed units |
| |
| if Ekind (P_Name) = E_Package and then From_Limited_With (P_Name) then |
| if From_Limited_With (Id) |
| or else Is_Type (Id) |
| or else Ekind (Id) = E_Package |
| then |
| null; |
| else |
| Error_Msg_N |
| ("limited withed package can only be used to access incomplete " |
| & "types", N); |
| end if; |
| end if; |
| |
| if Is_Task_Type (P_Name) |
| and then ((Ekind (Id) = E_Entry |
| and then Nkind (Parent (N)) /= N_Attribute_Reference) |
| or else |
| (Ekind (Id) = E_Entry_Family |
| and then |
| Nkind (Parent (Parent (N))) /= N_Attribute_Reference)) |
| then |
| -- If both the task type and the entry are in scope, this may still |
| -- be the expanded name of an entry formal. |
| |
| if In_Open_Scopes (Id) |
| and then Nkind (Parent (N)) = N_Selected_Component |
| then |
| null; |
| |
| else |
| -- It is an entry call after all, either to the current task |
| -- (which will deadlock) or to an enclosing task. |
| |
| Analyze_Selected_Component (N); |
| return; |
| end if; |
| end if; |
| |
| case Nkind (N) is |
| when N_Selected_Component => |
| Reinit_Field_To_Zero (N, F_Is_Prefixed_Call); |
| Change_Selected_Component_To_Expanded_Name (N); |
| |
| when N_Expanded_Name => |
| null; |
| |
| when others => |
| pragma Assert (False); |
| end case; |
| |
| -- Preserve relevant elaboration-related attributes of the context which |
| -- are no longer available or very expensive to recompute once analysis, |
| -- resolution, and expansion are over. |
| |
| Mark_Elaboration_Attributes |
| (N_Id => N, |
| Checks => True, |
| Modes => True, |
| Warnings => True); |
| |
| -- Set appropriate type |
| |
| if Is_Type (Id) then |
| Set_Etype (N, Id); |
| else |
| Set_Etype (N, Get_Full_View (Etype (Id))); |
| end if; |
| |
| -- Do style check and generate reference, but skip both steps if this |
| -- entity has homonyms, since we may not have the right homonym set yet. |
| -- The proper homonym will be set during the resolve phase. |
| |
| if Has_Homonym (Id) then |
| Set_Entity (N, Id); |
| |
| else |
| Set_Entity_Or_Discriminal (N, Id); |
| |
| case Known_To_Be_Assigned (N, Only_LHS => True) is |
| when True => |
| Generate_Reference (Id, N, 'm'); |
| |
| when False => |
| Generate_Reference (Id, N, 'r'); |
| |
| end case; |
| end if; |
| |
| -- Check for violation of No_Wide_Characters |
| |
| Check_Wide_Character_Restriction (Id, N); |
| |
| -- If the Ekind of the entity is Void, it means that all homonyms are |
| -- hidden from all visibility (RM 8.3(5,14-20)). |
| |
| if Ekind (Id) = E_Void then |
| Premature_Usage (N); |
| |
| elsif Is_Overloadable (Id) and then Present (Homonym (Id)) then |
| declare |
| H : Entity_Id := Homonym (Id); |
| |
| begin |
| while Present (H) loop |
| if Scope (H) = Scope (Id) |
| and then (not Is_Hidden (H) |
| or else Is_Immediately_Visible (H)) |
| then |
| Collect_Interps (N); |
| exit; |
| end if; |
| |
| H := Homonym (H); |
| end loop; |
| |
| -- If an extension of System is present, collect possible explicit |
| -- overloadings declared in the extension. |
| |
| if Chars (P_Name) = Name_System |
| and then Scope (P_Name) = Standard_Standard |
| and then Present (System_Extend_Unit) |
| and then Present_System_Aux (N) |
| then |
| H := Current_Entity (Id); |
| |
| while Present (H) loop |
| if Scope (H) = System_Aux_Id then |
| Add_One_Interp (N, H, Etype (H)); |
| end if; |
| |
| H := Homonym (H); |
| end loop; |
| end if; |
| end; |
| end if; |
| |
| if Nkind (Selector_Name (N)) = N_Operator_Symbol |
| and then Scope (Id) /= Standard_Standard |
| then |
| -- In addition to user-defined operators in the given scope, there |
| -- may be an implicit instance of the predefined operator. The |
| -- operator (defined in Standard) is found in Has_Implicit_Operator, |
| -- and added to the interpretations. Procedure Add_One_Interp will |
| -- determine which hides which. |
| |
| if Has_Implicit_Operator (N) then |
| null; |
| end if; |
| end if; |
| |
| -- If there is a single interpretation for N we can generate a |
| -- reference to the unique entity found. |
| |
| if Is_Overloadable (Id) and then not Is_Overloaded (N) then |
| Generate_Reference (Id, N); |
| end if; |
| |
| -- Mark relevant use-type and use-package clauses as effective if the |
| -- node in question is not overloaded and therefore does not require |
| -- resolution. |
| |
| if Nkind (N) not in N_Subexpr or else not Is_Overloaded (N) then |
| Mark_Use_Clauses (N); |
| end if; |
| |
| Check_Restriction_No_Use_Of_Entity (N); |
| |
| -- Annotate the tree by creating a variable reference marker in case the |
| -- original variable reference is folded or optimized away. The variable |
| -- reference marker is automatically saved for later examination by the |
| -- ABE Processing phase. Variable references which act as actuals in a |
| -- call require special processing and are left to Resolve_Actuals. The |
| -- reference is a write when it appears on the left hand side of an |
| -- assignment. |
| |
| if Needs_Variable_Reference_Marker |
| (N => N, |
| Calls_OK => False) |
| then |
| declare |
| Is_Assignment_LHS : constant Boolean := Known_To_Be_Assigned (N); |
| |
| begin |
| Build_Variable_Reference_Marker |
| (N => N, |
| Read => not Is_Assignment_LHS, |
| Write => Is_Assignment_LHS); |
| end; |
| end if; |
| end Find_Expanded_Name; |
| |
| -------------------- |
| -- Find_First_Use -- |
| -------------------- |
| |
| function Find_First_Use (Use_Clause : Node_Id) return Node_Id is |
| Curr : Node_Id; |
| |
| begin |
| -- Loop through the Prev_Use_Clause chain |
| |
| Curr := Use_Clause; |
| while Present (Prev_Use_Clause (Curr)) loop |
| Curr := Prev_Use_Clause (Curr); |
| end loop; |
| |
| return Curr; |
| end Find_First_Use; |
| |
| ------------------------- |
| -- Find_Renamed_Entity -- |
| ------------------------- |
| |
| function Find_Renamed_Entity |
| (N : Node_Id; |
| Nam : Node_Id; |
| New_S : Entity_Id; |
| Is_Actual : Boolean := False) return Entity_Id |
| is |
| Ind : Interp_Index; |
| I1 : Interp_Index := 0; -- Suppress junk warnings |
| It : Interp; |
| It1 : Interp; |
| Old_S : Entity_Id; |
| Inst : Entity_Id; |
| |
| function Find_Nearer_Entity |
| (New_S : Entity_Id; |
| Old1_S : Entity_Id; |
| Old2_S : Entity_Id) return Entity_Id; |
| -- Determine whether one of Old_S1 and Old_S2 is nearer to New_S than |
| -- the other, and return it if so. Return Empty otherwise. We use this |
| -- in conjunction with Inherit_Renamed_Profile to simplify later type |
| -- disambiguation for actual subprograms in instances. |
| |
| function Is_Visible_Operation (Op : Entity_Id) return Boolean; |
| -- If the renamed entity is an implicit operator, check whether it is |
| -- visible because its operand type is properly visible. This check |
| -- applies to explicit renamed entities that appear in the source in a |
| -- renaming declaration or a formal subprogram instance, but not to |
| -- default generic actuals with a name. |
| |
| function Report_Overload return Entity_Id; |
| -- List possible interpretations, and specialize message in the |
| -- case of a generic actual. |
| |
| function Within (Inner, Outer : Entity_Id) return Boolean; |
| -- Determine whether a candidate subprogram is defined within the |
| -- enclosing instance. If yes, it has precedence over outer candidates. |
| |
| -------------------------- |
| -- Find_Nearer_Entity -- |
| -------------------------- |
| |
| function Find_Nearer_Entity |
| (New_S : Entity_Id; |
| Old1_S : Entity_Id; |
| Old2_S : Entity_Id) return Entity_Id |
| is |
| New_F : Entity_Id; |
| Old1_F : Entity_Id; |
| Old2_F : Entity_Id; |
| Anc_T : Entity_Id; |
| |
| begin |
| New_F := First_Formal (New_S); |
| Old1_F := First_Formal (Old1_S); |
| Old2_F := First_Formal (Old2_S); |
| |
| -- The criterion is whether the type of the formals of one of Old1_S |
| -- and Old2_S is an ancestor subtype of the type of the corresponding |
| -- formals of New_S while the other is not (we already know that they |
| -- are all subtypes of the same base type). |
| |
| -- This makes it possible to find the more correct renamed entity in |
| -- the case of a generic instantiation nested in an enclosing one for |
| -- which different formal types get the same actual type, which will |
| -- in turn make it possible for Inherit_Renamed_Profile to preserve |
| -- types on formal parameters and ultimately simplify disambiguation. |
| |
| -- Consider the follow package G: |
| |
| -- generic |
| -- type Item_T is private; |
| -- with function Compare (L, R: Item_T) return Boolean is <>; |
| |
| -- type Bound_T is private; |
| -- with function Compare (L, R : Bound_T) return Boolean is <>; |
| -- package G is |
| -- ... |
| -- end G; |
| |
| -- package body G is |
| -- package My_Inner is Inner_G (Bound_T); |
| -- ... |
| -- end G; |
| |
| -- with the following package Inner_G: |
| |
| -- generic |
| -- type T is private; |
| -- with function Compare (L, R: T) return Boolean is <>; |
| -- package Inner_G is |
| -- function "<" (L, R: T) return Boolean is (Compare (L, R)); |
| -- end Inner_G; |
| |
| -- If G is instantiated on the same actual type with a single Compare |
| -- function: |
| |
| -- type T is ... |
| -- function Compare (L, R : T) return Boolean; |
| -- package My_G is new (T, T); |
| |
| -- then the renaming generated for Compare in the inner instantiation |
| -- is ambiguous: it can rename either of the renamings generated for |
| -- the outer instantiation. Now if the first one is picked up, then |
| -- the subtypes of the formal parameters of the renaming will not be |
| -- preserved in Inherit_Renamed_Profile because they are subtypes of |
| -- the Bound_T formal type and not of the Item_T formal type, so we |
| -- need to arrange for the second one to be picked up instead. |
| |
| while Present (New_F) loop |
| if Etype (Old1_F) /= Etype (Old2_F) then |
| Anc_T := Ancestor_Subtype (Etype (New_F)); |
| |
| if Etype (Old1_F) = Anc_T then |
| return Old1_S; |
| elsif Etype (Old2_F) = Anc_T then |
| return Old2_S; |
| end if; |
| end if; |
| |
| Next_Formal (New_F); |
| Next_Formal (Old1_F); |
| Next_Formal (Old2_F); |
| end loop; |
| |
| pragma Assert (No (Old1_F)); |
| pragma Assert (No (Old2_F)); |
| |
| return Empty; |
| end Find_Nearer_Entity; |
| |
| -------------------------- |
| -- Is_Visible_Operation -- |
| -------------------------- |
| |
| function Is_Visible_Operation (Op : Entity_Id) return Boolean is |
| Scop : Entity_Id; |
| Typ : Entity_Id; |
| Btyp : Entity_Id; |
| |
| begin |
| if Ekind (Op) /= E_Operator |
| or else Scope (Op) /= Standard_Standard |
| or else (In_Instance |
| and then (not Is_Actual |
| or else Present (Enclosing_Instance))) |
| then |
| return True; |
| |
| else |
| -- For a fixed point type operator, check the resulting type, |
| -- because it may be a mixed mode integer * fixed operation. |
| |
| if Present (Next_Formal (First_Formal (New_S))) |
| and then Is_Fixed_Point_Type (Etype (New_S)) |
| then |
| Typ := Etype (New_S); |
| else |
| Typ := Etype (First_Formal (New_S)); |
| end if; |
| |
| Btyp := Base_Type (Typ); |
| |
| if Nkind (Nam) /= N_Expanded_Name then |
| return (In_Open_Scopes (Scope (Btyp)) |
| or else Is_Potentially_Use_Visible (Btyp) |
| or else In_Use (Btyp) |
| or else In_Use (Scope (Btyp))); |
| |
| else |
| Scop := Entity (Prefix (Nam)); |
| |
| if Ekind (Scop) = E_Package |
| and then Present (Renamed_Entity (Scop)) |
| then |
| Scop := Renamed_Entity (Scop); |
| end if; |
| |
| -- Operator is visible if prefix of expanded name denotes |
| -- scope of type, or else type is defined in System_Aux |
| -- and the prefix denotes System. |
| |
| return Scope (Btyp) = Scop |
| or else (Scope (Btyp) = System_Aux_Id |
| and then Scope (Scope (Btyp)) = Scop); |
| end if; |
| end if; |
| end Is_Visible_Operation; |
| |
| ------------ |
| -- Within -- |
| ------------ |
| |
| function Within (Inner, Outer : Entity_Id) return Boolean is |
| Sc : Entity_Id; |
| |
| begin |
| Sc := Scope (Inner); |
| while Sc /= Standard_Standard loop |
| if Sc = Outer then |
| return True; |
| else |
| Sc := Scope (Sc); |
| end if; |
| end loop; |
| |
| return False; |
| end Within; |
| |
| --------------------- |
| -- Report_Overload -- |
| --------------------- |
| |
| function Report_Overload return Entity_Id is |
| begin |
| if Is_Actual then |
| Error_Msg_NE -- CODEFIX |
| ("ambiguous actual subprogram&, " & |
| "possible interpretations:", N, Nam); |
| else |
| Error_Msg_N -- CODEFIX |
| ("ambiguous subprogram, " & |
| "possible interpretations:", N); |
| end if; |
| |
| List_Interps (Nam, N); |
| return Old_S; |
| end Report_Overload; |
| |
| -- Start of processing for Find_Renamed_Entity |
| |
| begin |
| Old_S := Any_Id; |
| Candidate_Renaming := Empty; |
| |
| if Is_Overloaded (Nam) then |
| Get_First_Interp (Nam, Ind, It); |
| while Present (It.Nam) loop |
| if Entity_Matches_Spec (It.Nam, New_S) |
| and then Is_Visible_Operation (It.Nam) |
| then |
| if Old_S /= Any_Id then |
| |
| -- Note: The call to Disambiguate only happens if a |
| -- previous interpretation was found, in which case I1 |
| -- has received a value. |
| |
| It1 := Disambiguate (Nam, I1, Ind, Etype (Old_S)); |
| |
| if It1 = No_Interp then |
| Inst := Enclosing_Instance; |
| |
| if Present (Inst) then |
| if Within (It.Nam, Inst) then |
| if Within (Old_S, Inst) then |
| declare |
| It_D : constant Uint := |
| Scope_Depth_Default_0 (It.Nam); |
| Old_D : constant Uint := |
| Scope_Depth_Default_0 (Old_S); |
| N_Ent : Entity_Id; |
| begin |
| -- Choose the innermost subprogram, which |
| -- would hide the outer one in the generic. |
| |
| if Old_D > It_D then |
| return Old_S; |
| elsif It_D > Old_D then |
| return It.Nam; |
| end if; |
| |
| -- Otherwise, if we can determine that one |
| -- of the entities is nearer to the renaming |
| -- than the other, choose it. If not, then |
| -- return the newer one as done historically. |
| |
| N_Ent := |
| Find_Nearer_Entity (New_S, Old_S, It.Nam); |
| if Present (N_Ent) then |
| return N_Ent; |
| else |
| return It.Nam; |
| end if; |
| end; |
| end if; |
| |
| elsif Within (Old_S, Inst) then |
| return Old_S; |
| |
| else |
| return Report_Overload; |
| end if; |
| |
| -- If not within an instance, ambiguity is real |
| |
| else |
| return Report_Overload; |
| end if; |
| |
| else |
| Old_S := It1.Nam; |
| exit; |
| end if; |
| |
| else |
| I1 := Ind; |
| Old_S := It.Nam; |
| end if; |
| |
| elsif |
| Present (First_Formal (It.Nam)) |
| and then Present (First_Formal (New_S)) |
| and then (Base_Type (Etype (First_Formal (It.Nam))) = |
| Base_Type (Etype (First_Formal (New_S)))) |
| then |
| Candidate_Renaming := It.Nam; |
| end if; |
| |
| Get_Next_Interp (Ind, It); |
| end loop; |
| |
| Set_Entity (Nam, Old_S); |
| |
| if Old_S /= Any_Id then |
| Set_Is_Overloaded (Nam, False); |
| end if; |
| |
| -- Non-overloaded case |
| |
| else |
| if Is_Actual |
| and then Present (Enclosing_Instance) |
| and then Entity_Matches_Spec (Entity (Nam), New_S) |
| then |
| Old_S := Entity (Nam); |
| |
| elsif Entity_Matches_Spec (Entity (Nam), New_S) then |
| Candidate_Renaming := New_S; |
| |
| if Is_Visible_Operation (Entity (Nam)) then |
| Old_S := Entity (Nam); |
| end if; |
| |
| elsif Present (First_Formal (Entity (Nam))) |
| and then Present (First_Formal (New_S)) |
| and then (Base_Type (Etype (First_Formal (Entity (Nam)))) = |
| Base_Type (Etype (First_Formal (New_S)))) |
| then |
| Candidate_Renaming := Entity (Nam); |
| end if; |
| end if; |
| |
| return Old_S; |
| end Find_Renamed_Entity; |
| |
| ----------------------------- |
| -- Find_Selected_Component -- |
| ----------------------------- |
| |
| procedure Find_Selected_Component (N : Node_Id) is |
| P : constant Node_Id := Prefix (N); |
| |
| P_Name : Entity_Id; |
| -- Entity denoted by prefix |
| |
| P_Type : Entity_Id; |
| -- and its type |
| |
| Nam : Node_Id; |
| |
| function Available_Subtype return Boolean; |
| -- A small optimization: if the prefix is constrained and the component |
| -- is an array type we may already have a usable subtype for it, so we |
| -- can use it rather than generating a new one, because the bounds |
| -- will be the values of the discriminants and not discriminant refs. |
| -- This simplifies value tracing in GNATprove. For consistency, both |
| -- the entity name and the subtype come from the constrained component. |
| |
| -- This is only used in GNATprove mode: when generating code it may be |
| -- necessary to create an itype in the scope of use of the selected |
| -- component, e.g. in the context of a expanded record equality. |
| |
| function Is_Reference_In_Subunit return Boolean; |
| -- In a subunit, the scope depth is not a proper measure of hiding, |
| -- because the context of the proper body may itself hide entities in |
| -- parent units. This rare case requires inspecting the tree directly |
| -- because the proper body is inserted in the main unit and its context |
| -- is simply added to that of the parent. |
| |
| ----------------------- |
| -- Available_Subtype -- |
| ----------------------- |
| |
| function Available_Subtype return Boolean is |
| Comp : Entity_Id; |
| |
| begin |
| if GNATprove_Mode then |
| Comp := First_Entity (Etype (P)); |
| while Present (Comp) loop |
| if Chars (Comp) = Chars (Selector_Name (N)) then |
| Set_Etype (N, Etype (Comp)); |
| Set_Entity (Selector_Name (N), Comp); |
| Set_Etype (Selector_Name (N), Etype (Comp)); |
| return True; |
| end if; |
| |
| Next_Component (Comp); |
| end loop; |
| end if; |
| |
| return False; |
| end Available_Subtype; |
| |
| ----------------------------- |
| -- Is_Reference_In_Subunit -- |
| ----------------------------- |
| |
| function Is_Reference_In_Subunit return Boolean is |
| Clause : Node_Id; |
| Comp_Unit : Node_Id; |
| |
| begin |
| Comp_Unit := N; |
| while Present (Comp_Unit) |
| and then Nkind (Comp_Unit) /= N_Compilation_Unit |
| loop |
| Comp_Unit := Parent (Comp_Unit); |
| end loop; |
| |
| if No (Comp_Unit) or else Nkind (Unit (Comp_Unit)) /= N_Subunit then |
| return False; |
| end if; |
| |
| -- Now check whether the package is in the context of the subunit |
| |
| Clause := First (Context_Items (Comp_Unit)); |
| while Present (Clause) loop |
| if Nkind (Clause) = N_With_Clause |
| and then Entity (Name (Clause)) = P_Name |
| then |
| return True; |
| end if; |
| |
| Next (Clause); |
| end loop; |
| |
| return False; |
| end Is_Reference_In_Subunit; |
| |
| -- Start of processing for Find_Selected_Component |
| |
| begin |
| Analyze (P); |
| |
| if Nkind (P) = N_Error then |
| return; |
| end if; |
| |
| -- If the selector already has an entity, the node has been constructed |
| -- in the course of expansion, and is known to be valid. Do not verify |
| -- that it is defined for the type (it may be a private component used |
| -- in the expansion of record equality). |
| |
| if Present (Entity (Selector_Name (N))) then |
| if No (Etype (N)) or else Etype (N) = Any_Type then |
| declare |
| Sel_Name : constant Node_Id := Selector_Name (N); |
| Selector : constant Entity_Id := Entity (Sel_Name); |
| C_Etype : Node_Id; |
| |
| begin |
| Set_Etype (Sel_Name, Etype (Selector)); |
| |
| if not Is_Entity_Name (P) then |
| Resolve (P); |
| end if; |
| |
| -- Build an actual subtype except for the first parameter |
| -- of an init proc, where this actual subtype is by |
| -- definition incorrect, since the object is uninitialized |
| -- (and does not even have defined discriminants etc.) |
| |
| if Is_Entity_Name (P) |
| and then Ekind (Entity (P)) = E_Function |
| then |
| Nam := New_Copy (P); |
| |
| if Is_Overloaded (P) then |
| Save_Interps (P, Nam); |
| end if; |
| |
| Rewrite (P, Make_Function_Call (Sloc (P), Name => Nam)); |
| Analyze_Call (P); |
| Analyze_Selected_Component (N); |
| return; |
| |
| elsif Ekind (Selector) = E_Component |
| and then (not Is_Entity_Name (P) |
| or else Chars (Entity (P)) /= Name_uInit) |
| then |
| -- Check if we already have an available subtype we can use |
| |
| if Ekind (Etype (P)) = E_Record_Subtype |
| and then Nkind (Parent (Etype (P))) = N_Subtype_Declaration |
| and then Is_Array_Type (Etype (Selector)) |
| and then not Is_Packed (Etype (Selector)) |
| and then Available_Subtype |
| then |
| return; |
| |
| -- Do not build the subtype when referencing components of |
| -- dispatch table wrappers. Required to avoid generating |
| -- elaboration code with HI runtimes. |
| |
| elsif Is_RTE (Scope (Selector), RE_Dispatch_Table_Wrapper) |
| or else |
| Is_RTE (Scope (Selector), RE_No_Dispatch_Table_Wrapper) |
| then |
| C_Etype := Empty; |
| else |
| C_Etype := |
| Build_Actual_Subtype_Of_Component |
| (Etype (Selector), N); |
| end if; |
| |
| else |
| C_Etype := Empty; |
| end if; |
| |
| if No (C_Etype) then |
| C_Etype := Etype (Selector); |
| else |
| Insert_Action (N, C_Etype); |
| C_Etype := Defining_Identifier (C_Etype); |
| end if; |
| |
| Set_Etype (N, C_Etype); |
| end; |
| |
| -- If the selected component appears within a default expression |
| -- and it has an actual subtype, the preanalysis has not yet |
| -- completed its analysis, because Insert_Actions is disabled in |
| -- that context. Within the init proc of the enclosing type we |
| -- must complete this analysis, if an actual subtype was created. |
| |
| elsif Inside_Init_Proc then |
| declare |
| Typ : constant Entity_Id := Etype (N); |
| Decl : constant Node_Id := Declaration_Node (Typ); |
| begin |
| if Nkind (Decl) = N_Subtype_Declaration |
| and then not Analyzed (Decl) |
| and then Is_List_Member (Decl) |
| and then No (Parent (Decl)) |
| then |
| Remove (Decl); |
| Insert_Action (N, Decl); |
| end if; |
| end; |
| end if; |
| |
| return; |
| |
| elsif Is_Entity_Name (P) then |
| P_Name := Entity (P); |
| |
| -- The prefix may denote an enclosing type which is the completion |
| -- of an incomplete type declaration. |
| |
| if Is_Type (P_Name) then |
| Set_Entity (P, Get_Full_View (P_Name)); |
| Set_Etype (P, Entity (P)); |
| P_Name := Entity (P); |
| end if; |
| |
| P_Type := Base_Type (Etype (P)); |
| |
| if Debug_Flag_E then |
| Write_Str ("Found prefix type to be "); |
| Write_Entity_Info (P_Type, " "); Write_Eol; |
| end if; |
| |
| -- If the prefix's type is an access type, get to the record type |
| |
| if Is_Access_Type (P_Type) then |
| P_Type := Implicitly_Designated_Type (P_Type); |
| end if; |
| |
| -- First check for components of a record object (not the result of |
| -- a call, which is handled below). This also covers the case where |
| -- the extension feature that supports the prefixed form of calls |
| -- for primitives of untagged types is enabled (excluding concurrent |
| -- cases, which are handled further below). |
| |
| if Is_Type (P_Type) |
| and then (Has_Components (P_Type) |
| or else (Core_Extensions_Allowed |
| and then not Is_Concurrent_Type (P_Type))) |
| and then not Is_Overloadable (P_Name) |
| and then not Is_Type (P_Name) |
| then |
| -- Selected component of record. Type checking will validate |
| -- name of selector. |
| |
| -- ??? Could we rewrite an implicit dereference into an explicit |
| -- one here? |
| |
| Analyze_Selected_Component (N); |
| |
| -- Reference to type name in predicate/invariant expression |
| |
| elsif Is_Concurrent_Type (P_Type) |
| and then not In_Open_Scopes (P_Name) |
| and then (not Is_Concurrent_Type (Etype (P_Name)) |
| or else not In_Open_Scopes (Etype (P_Name))) |
| then |
| -- Call to protected operation or entry. Type checking is |
| -- needed on the prefix. |
| |
| Analyze_Selected_Component (N); |
| |
| elsif (In_Open_Scopes (P_Name) |
| and then Ekind (P_Name) /= E_Void |
| and then not Is_Overloadable (P_Name)) |
| or else (Is_Concurrent_Type (Etype (P_Name)) |
| and then In_Open_Scopes (Etype (P_Name))) |
| then |
| -- Prefix denotes an enclosing loop, block, or task, i.e. an |
| -- enclosing construct that is not a subprogram or accept. |
| |
| -- A special case: a protected body may call an operation |
| -- on an external object of the same type, in which case it |
| -- is not an expanded name. If the prefix is the type itself, |
| -- or the context is a single synchronized object it can only |
| -- be interpreted as an expanded name. |
| |
| if Is_Concurrent_Type (Etype (P_Name)) then |
| if Is_Type (P_Name) |
| or else Present (Anonymous_Object (Etype (P_Name))) |
| then |
| Find_Expanded_Name (N); |
| |
| else |
| Analyze_Selected_Component (N); |
| return; |
| end if; |
| |
| else |
| Find_Expanded_Name (N); |
| end if; |
| |
| elsif Ekind (P_Name) = E_Package then |
| Find_Expanded_Name (N); |
| |
| elsif Is_Overloadable (P_Name) then |
| |
| -- The subprogram may be a renaming (of an enclosing scope) as |
| -- in the case of the name of the generic within an instantiation. |
| |
| if Ekind (P_Name) in E_Procedure | E_Function |
| and then Present (Alias (P_Name)) |
| and then Is_Generic_Instance (Alias (P_Name)) |
| then |
| P_Name := Alias (P_Name); |
| end if; |
| |
| if Is_Overloaded (P) then |
| |
| -- The prefix must resolve to a unique enclosing construct |
| |
| declare |
| Found : Boolean := False; |
| Ind : Interp_Index; |
| It : Interp; |
| |
| begin |
| Get_First_Interp (P, Ind, It); |
| while Present (It.Nam) loop |
| if In_Open_Scopes (It.Nam) then |
| if Found then |
| Error_Msg_N ( |
| "prefix must be unique enclosing scope", N); |
| Set_Entity (N, Any_Id); |
| Set_Etype (N, Any_Type); |
| return; |
| |
| else |
| Found := True; |
| P_Name := It.Nam; |
| end if; |
| end if; |
| |
| Get_Next_Interp (Ind, It); |
| end loop; |
| end; |
| end if; |
| |
| if In_Open_Scopes (P_Name) then |
| Set_Entity (P, P_Name); |
| Set_Is_Overloaded (P, False); |
| Find_Expanded_Name (N); |
| |
| else |
| -- If no interpretation as an expanded name is possible, it |
| -- must be a selected component of a record returned by a |
| -- function call. Reformat prefix as a function call, the rest |
| -- is done by type resolution. |
| |
| -- Error if the prefix is procedure or entry, as is P.X |
| |
| if Ekind (P_Name) /= E_Function |
| and then |
| (not Is_Overloaded (P) |
| or else Nkind (Parent (N)) = N_Procedure_Call_Statement) |
| then |
| -- Prefix may mention a package that is hidden by a local |
| -- declaration: let the user know. Scan the full homonym |
| -- chain, the candidate package may be anywhere on it. |
| |
| if Present (Homonym (Current_Entity (P_Name))) then |
| P_Name := Current_Entity (P_Name); |
| |
| while Present (P_Name) loop |
| exit when Ekind (P_Name) = E_Package; |
| P_Name := Homonym (P_Name); |
| end loop; |
| |
| if Present (P_Name) then |
| if not Is_Reference_In_Subunit then |
| Error_Msg_Sloc := Sloc (Entity (Prefix (N))); |
| Error_Msg_NE |
| ("package& is hidden by declaration#", N, P_Name); |
| end if; |
| |
| Set_Entity (Prefix (N), P_Name); |
| Find_Expanded_Name (N); |
| return; |
| |
| else |
| P_Name := Entity (Prefix (N)); |
| end if; |
| end if; |
| |
| Error_Msg_NE |
| ("invalid prefix in selected component&", N, P_Name); |
| Change_Selected_Component_To_Expanded_Name (N); |
| Set_Entity (N, Any_Id); |
| Set_Etype (N, Any_Type); |
| |
| -- Here we have a function call, so do the reformatting |
| |
| else |
| Nam := New_Copy (P); |
| Save_Interps (P, Nam); |
| |
| -- We use Replace here because this is one of those cases |
| -- where the parser has missclassified the node, and we fix |
| -- things up and then do the semantic analysis on the fixed |
| -- up node. Normally we do this using one of the Sinfo.CN |
| -- routines, but this is too tricky for that. |
| |
| -- Note that using Rewrite would be wrong, because we would |
| -- have a tree where the original node is unanalyzed. |
| |
| Replace (P, |
| Make_Function_Call (Sloc (P), Name => Nam)); |
| |
| -- Now analyze the reformatted node |
| |
| Analyze_Call (P); |
| |
| -- If the prefix is illegal after this transformation, there |
| -- may be visibility errors on the prefix. The safest is to |
| -- treat the selected component as an error. |
| |
| if Error_Posted (P) then |
| Set_Etype (N, Any_Type); |
| return; |
| |
| else |
| Analyze_Selected_Component (N); |
| end if; |
| end if; |
| end if; |
| |
| -- Remaining cases generate various error messages |
| |
| else |
| -- Format node as expanded name, to avoid cascaded errors |
| |
| Change_Selected_Component_To_Expanded_Name (N); |
| Set_Entity (N, Any_Id); |
| Set_Etype (N, Any_Type); |
| |
| -- Issue error message, but avoid this if error issued already. |
| -- Use identifier of prefix if one is available. |
| |
| if P_Name = Any_Id then |
| null; |
| |
| -- It is not an error if the prefix is the current instance of |
| -- type name, e.g. the expression of a type aspect, when it is |
| -- analyzed within a generic unit. We still have to verify that a |
| -- component of that name exists, and decorate the node |
| -- accordingly. |
| |
| elsif Is_Entity_Name (P) and then Is_Current_Instance (P) then |
| declare |
| Comp : Entity_Id; |
| |
| begin |
| Comp := First_Entity (Entity (P)); |
| while Present (Comp) loop |
| if Chars (Comp) = Chars (Selector_Name (N)) then |
| Set_Entity (N, Comp); |
| Set_Etype (N, Etype (Comp)); |
| Set_Entity (Selector_Name (N), Comp); |
| Set_Etype (Selector_Name (N), Etype (Comp)); |
| return; |
| end if; |
| |
| Next_Entity (Comp); |
| end loop; |
| end; |
| |
| elsif Ekind (P_Name) = E_Void then |
| Premature_Usage (P); |
| |
| elsif Ekind (P_Name) = E_Generic_Package then |
| Error_Msg_N ("prefix must not be a generic package", N); |
| Error_Msg_N ("\use package instantiation as prefix instead", N); |
| |
| elsif Nkind (P) /= N_Attribute_Reference then |
| |
| -- This may have been meant as a prefixed call to a primitive |
| -- of an untagged type. If it is a function call check type of |
| -- its first formal and add explanation. |
| |
| declare |
| F : constant Entity_Id := |
| Current_Entity (Selector_Name (N)); |
| begin |
| if Present (F) |
| and then Is_Overloadable (F) |
| and then Present (First_Entity (F)) |
| and then not Is_Tagged_Type (Etype (First_Entity (F))) |
| then |
| Error_Msg_N |
| ("prefixed call is only allowed for objects of a " |
| & "tagged type unless -gnatX is used", N); |
| |
| if not Core_Extensions_Allowed |
| and then |
| Try_Object_Operation (N, Allow_Extensions => True) |
| then |
| Error_Msg_N |
| ("\using -gnatX would make the prefixed call legal", |
| N); |
| end if; |
| end if; |
| end; |
| |
| Error_Msg_N ("invalid prefix in selected component&", P); |
| |
| if Is_Incomplete_Type (P_Type) |
| and then Is_Access_Type (Etype (P)) |
| then |
| Error_Msg_N |
| ("\dereference must not be of an incomplete type " |
| & "(RM 3.10.1)", P); |
| end if; |
| |
| else |
| Error_Msg_N ("invalid prefix in selected component", P); |
| end if; |
| end if; |
| else |
| -- If prefix is not the name of an entity, it must be an expression, |
| -- whose type is appropriate for a record. This is determined by |
| -- type resolution. |
| |
| Analyze_Selected_Component (N); |
| end if; |
| |
| Analyze_Dimension (N); |
| end Find_Selected_Component; |
| |
| --------------- |
| -- Find_Type -- |
| --------------- |
| |
| procedure Find_Type (N : Node_Id) is |
| C : Entity_Id; |
| Typ : Entity_Id; |
| T : Entity_Id; |
| T_Name : Entity_Id; |
| |
| begin |
| if N = Error then |
| return; |
| |
| elsif Nkind (N) = N_Attribute_Reference then |
| |
| -- Class attribute. This is not valid in Ada 83 mode, but we do not |
| -- need to enforce that at this point, since the declaration of the |
| -- tagged type in the prefix would have been flagged already. |
| |
| if Attribute_Name (N) = Name_Class then |
| Check_Restriction (No_Dispatch, N); |
| Find_Type (Prefix (N)); |
| |
| -- Propagate error from bad prefix |
| |
| if Etype (Prefix (N)) = Any_Type then |
| Set_Entity (N, Any_Type); |
| Set_Etype (N, Any_Type); |
| return; |
| end if; |
| |
| T := Base_Type (Entity (Prefix (N))); |
| |
| -- Case where type is not known to be tagged. Its appearance in |
| -- the prefix of the 'Class attribute indicates that the full view |
| -- will be tagged. |
| |
| if not Is_Tagged_Type (T) then |
| if Ekind (T) = E_Incomplete_Type then |
| |
| -- It is legal to denote the class type of an incomplete |
| -- type. The full type will have to be tagged, of course. |
| -- In Ada 2005 this usage is declared obsolescent, so we |
| -- warn accordingly. This usage is only legal if the type |
| -- is completed in the current scope, and not for a limited |
| -- view of a type. |
| |
| if Ada_Version >= Ada_2005 then |
| |
| -- Test whether the Available_View of a limited type view |
| -- is tagged, since the limited view may not be marked as |
| -- tagged if the type itself has an untagged incomplete |
| -- type view in its package. |
| |
| if From_Limited_With (T) |
| and then not Is_Tagged_Type (Available_View (T)) |
| then |
| Error_Msg_N |
| ("prefix of Class attribute must be tagged", N); |
| Set_Etype (N, Any_Type); |
| Set_Entity (N, Any_Type); |
| return; |
| |
| else |
| if Restriction_Check_Required (No_Obsolescent_Features) |
| then |
| Check_Restriction |
| (No_Obsolescent_Features, Prefix (N)); |
| end if; |
| |
| if Warn_On_Obsolescent_Feature then |
| Error_Msg_N |
| ("applying ''Class to an untagged incomplete type" |
| & " is an obsolescent feature (RM J.11)?r?", N); |
| end if; |
| end if; |
| end if; |
| |
| Set_Is_Tagged_Type (T); |
| Set_Direct_Primitive_Operations (T, New_Elmt_List); |
| Make_Class_Wide_Type (T); |
| Set_Entity (N, Class_Wide_Type (T)); |
| Set_Etype (N, Class_Wide_Type (T)); |
| |
| elsif Ekind (T) = E_Private_Type |
| and then not Is_Generic_Type (T) |
| and then In_Private_Part (Scope (T)) |
| then |
| -- The Class attribute can be applied to an untagged private |
| -- type fulfilled by a tagged type prior to the full type |
| -- declaration (but only within the parent package's private |
| -- part). Create the class-wide type now and check that the |
| -- full type is tagged later during its analysis. Note that |
| -- we do not mark the private type as tagged, unlike the |
| -- case of incomplete types, because the type must still |
| -- appear untagged to outside units. |
| |
| if No (Class_Wide_Type (T)) then |
| Make_Class_Wide_Type (T); |
| end if; |
| |
| Set_Entity (N, Class_Wide_Type (T)); |
| Set_Etype (N, Class_Wide_Type (T)); |
| |
| else |
| -- Should we introduce a type Any_Tagged and use Wrong_Type |
| -- here, it would be a bit more consistent??? |
| |
| Error_Msg_NE |
| ("tagged type required, found}", |
| Prefix (N), First_Subtype (T)); |
| Set_Entity (N, Any_Type); |
| return; |
| end if; |
| |
| -- Case of tagged type |
| |
| else |
| if Is_Concurrent_Type (T) then |
| if No (Corresponding_Record_Type (Entity (Prefix (N)))) then |
| |
| -- Previous error. Create a class-wide type for the |
| -- synchronized type itself, with minimal semantic |
| -- attributes, to catch other errors in some ACATS tests. |
| |
| pragma Assert (Serious_Errors_Detected /= 0); |
| Make_Class_Wide_Type (T); |
| C := Class_Wide_Type (T); |
| Set_First_Entity (C, First_Entity (T)); |
| |
| else |
| C := Class_Wide_Type |
| (Corresponding_Record_Type (Entity (Prefix (N)))); |
| end if; |
| |
| else |
| C := Class_Wide_Type (Entity (Prefix (N))); |
| end if; |
| |
| Set_Entity_With_Checks (N, C); |
| Generate_Reference (C, N); |
| Set_Etype (N, C); |
| end if; |
| |
| -- Base attribute, not allowed in Ada 83 |
| |
| elsif Attribute_Name (N) = Name_Base then |
| if Ada_Version = Ada_83 and then Comes_From_Source (N) then |
| Error_Msg_N |
| ("(Ada 83) Base attribute not allowed in subtype mark", N); |
| |
| else |
| Find_Type (Prefix (N)); |
| Typ := Entity (Prefix (N)); |
| |
| if Ada_Version >= Ada_95 |
| and then not Is_Scalar_Type (Typ) |
| and then not Is_Generic_Type (Typ) |
| then |
| Error_Msg_N |
| ("prefix of Base attribute must be scalar type", |
| Prefix (N)); |
| |
| elsif Warn_On_Redundant_Constructs |
| and then Base_Type (Typ) = Typ |
| then |
| Error_Msg_NE -- CODEFIX |
| ("redundant attribute, & is its own base type?r?", N, Typ); |
| end if; |
| |
| T := Base_Type (Typ); |
| |
| -- Rewrite attribute reference with type itself (see similar |
| -- processing in Analyze_Attribute, case Base). Preserve prefix |
| -- if present, for other legality checks. |
| |
| if Nkind (Prefix (N)) = N_Expanded_Name then |
| Rewrite (N, |
| Make_Expanded_Name (Sloc (N), |
| Chars => Chars (T), |
| Prefix => New_Copy (Prefix (Prefix (N))), |
| Selector_Name => New_Occurrence_Of (T, Sloc (N)))); |
| |
| else |
| Rewrite (N, New_Occurrence_Of (T, Sloc (N))); |
| end if; |
| |
| Set_Entity (N, T); |
| Set_Etype (N, T); |
| end if; |
| |
| elsif Attribute_Name (N) = Name_Stub_Type then |
| |
| -- This is handled in Analyze_Attribute |
| |
| Analyze (N); |
| |
| -- All other attributes are invalid in a subtype mark |
| |
| else |
| Error_Msg_N ("invalid attribute in subtype mark", N); |
| end if; |
| |
| else |
| Analyze (N); |
| |
| if Is_Entity_Name (N) then |
| T_Name := Entity (N); |
| else |
| Error_Msg_N ("subtype mark required in this context", N); |
| Set_Etype (N, Any_Type); |
| return; |
| end if; |
| |
| if T_Name = Any_Id or else Etype (N) = Any_Type then |
| |
| -- Undefined id. Make it into a valid type |
| |
| Set_Entity (N, Any_Type); |
| |
| elsif not Is_Type (T_Name) |
| and then T_Name /= Standard_Void_Type |
| then |
| Error_Msg_Sloc := Sloc (T_Name); |
| Error_Msg_N ("subtype mark required in this context", N); |
| Error_Msg_NE ("\\found & declared#", N, T_Name); |
| Set_Entity (N, Any_Type); |
| |
| else |
| -- If the type is an incomplete type created to handle |
| -- anonymous access components of a record type, then the |
| -- incomplete type is the visible entity and subsequent |
| -- references will point to it. Mark the original full |
| -- type as referenced, to prevent spurious warnings. |
| |
| if Is_Incomplete_Type (T_Name) |
| and then Present (Full_View (T_Name)) |
| and then not Comes_From_Source (T_Name) |
| then |
| Set_Referenced (Full_View (T_Name)); |
| end if; |
| |
| T_Name := Get_Full_View (T_Name); |
| |
| -- Ada 2005 (AI-251, AI-50217): Handle interfaces visible through |
| -- limited-with clauses |
| |
| if From_Limited_With (T_Name) |
| and then Is_Incomplete_Type (T_Name) |
| and then Present (Non_Limited_View (T_Name)) |
| and then Is_Interface (Non_Limited_View (T_Name)) |
| then |
| T_Name := Non_Limited_View (T_Name); |
| end if; |
| |
| if In_Open_Scopes (T_Name) then |
| if Ekind (Base_Type (T_Name)) = E_Task_Type then |
| |
| -- In Ada 2005, a task name can be used in an access |
| -- definition within its own body. |
| |
| if Ada_Version >= Ada_2005 |
| and then Nkind (Parent (N)) = N_Access_Definition |
| then |
| Set_Entity (N, T_Name); |
| Set_Etype (N, T_Name); |
| return; |
| |
| else |
| Error_Msg_N |
| ("task type cannot be used as type mark " & |
| "within its own spec or body", N); |
| end if; |
| |
| elsif Ekind (Base_Type (T_Name)) = E_Protected_Type then |
| |
| -- In Ada 2005, a protected name can be used in an access |
| -- definition within its own body. |
| |
| if Ada_Version >= Ada_2005 |
| and then Nkind (Parent (N)) = N_Access_Definition |
| then |
| Set_Entity (N, T_Name); |
| Set_Etype (N, T_Name); |
| return; |
| |
| else |
| Error_Msg_N |
| ("protected type cannot be used as type mark " & |
| "within its own spec or body", N); |
| end if; |
| |
| else |
| Error_Msg_N ("type declaration cannot refer to itself", N); |
| end if; |
| |
| Set_Etype (N, Any_Type); |
| Set_Entity (N, Any_Type); |
| Set_Error_Posted (T_Name); |
| return; |
| end if; |
| |
| Set_Entity (N, T_Name); |
| Set_Etype (N, T_Name); |
| end if; |
| end if; |
| |
| if Present (Etype (N)) and then Comes_From_Source (N) then |
| if Is_Fixed_Point_Type (Etype (N)) then |
| Check_Restriction (No_Fixed_Point, N); |
| elsif Is_Floating_Point_Type (Etype (N)) then |
| Check_Restriction (No_Floating_Point, N); |
| end if; |
| |
| -- A Ghost type must appear in a specific context |
| |
| if Is_Ghost_Entity (Etype (N)) then |
| Check_Ghost_Context (Etype (N), N); |
| end if; |
| end if; |
| end Find_Type; |
| |
| -------------------- |
| -- Has_Components -- |
| -------------------- |
| |
| function Has_Components (Typ : Entity_Id) return Boolean is |
| begin |
| return Is_Record_Type (Typ) |
| or else (Is_Private_Type (Typ) and then Has_Discriminants (Typ)) |
| or else (Is_Task_Type (Typ) and then Has_Discriminants (Typ)) |
| or else (Is_Incomplete_Type (Typ) |
| and then From_Limited_With (Typ) |
| and then Is_Record_Type (Available_View (Typ))); |
| end Has_Components; |
| |
| ------------------------------------ |
| -- Has_Implicit_Character_Literal -- |
| ------------------------------------ |
| |
| function Has_Implicit_Character_Literal (N : Node_Id) return Boolean is |
| Id : Entity_Id; |
| Found : Boolean := False; |
| P : constant Entity_Id := Entity (Prefix (N)); |
| Priv_Id : Entity_Id := Empty; |
| |
| begin |
| if Ekind (P) = E_Package and then not In_Open_Scopes (P) then |
| Priv_Id := First_Private_Entity (P); |
| end if; |
| |
| if P = Standard_Standard then |
| Change_Selected_Component_To_Expanded_Name (N); |
| Rewrite (N, Selector_Name (N)); |
| Analyze (N); |
| Set_Etype (Original_Node (N), Standard_Character); |
| return True; |
| end if; |
| |
| Id := First_Entity (P); |
| while Present (Id) and then Id /= Priv_Id loop |
| if Is_Standard_Character_Type (Id) and then Is_Base_Type (Id) then |
| |
| -- We replace the node with the literal itself, resolve as a |
| -- character, and set the type correctly. |
| |
| if not Found then |
| Change_Selected_Component_To_Expanded_Name (N); |
| Rewrite (N, Selector_Name (N)); |
| Analyze (N); |
| Set_Etype (N, Id); |
| Set_Etype (Original_Node (N), Id); |
| Found := True; |
| |
| else |
| -- More than one type derived from Character in given scope. |
| -- Collect all possible interpretations. |
| |
| Add_One_Interp (N, Id, Id); |
| end if; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| return Found; |
| end Has_Implicit_Character_Literal; |
| |
| ---------------------- |
| -- Has_Private_With -- |
| ---------------------- |
| |
| function Has_Private_With (E : Entity_Id) return Boolean is |
| Comp_Unit : constant Node_Id := Cunit (Current_Sem_Unit); |
| Item : Node_Id; |
| |
| begin |
| Item := First (Context_Items (Comp_Unit)); |
| while Present (Item) loop |
| if Nkind (Item) = N_With_Clause |
| and then Private_Present (Item) |
| and then Entity (Name (Item)) = E |
| then |
| return True; |
| end if; |
| |
| Next (Item); |
| end loop; |
| |
| return False; |
| end Has_Private_With; |
| |
| --------------------------- |
| -- Has_Implicit_Operator -- |
| --------------------------- |
| |
| function Has_Implicit_Operator (N : Node_Id) return Boolean is |
| Op_Id : constant Name_Id := Chars (Selector_Name (N)); |
| P : constant Entity_Id := Entity (Prefix (N)); |
| Id : Entity_Id; |
| Priv_Id : Entity_Id := Empty; |
| |
| procedure Add_Implicit_Operator |
| (T : Entity_Id; |
| Op_Type : Entity_Id := Empty); |
| -- Add implicit interpretation to node N, using the type for which a |
| -- predefined operator exists. If the operator yields a boolean type, |
| -- the Operand_Type is implicitly referenced by the operator, and a |
| -- reference to it must be generated. |
| |
| --------------------------- |
| -- Add_Implicit_Operator -- |
| --------------------------- |
| |
| procedure Add_Implicit_Operator |
| (T : Entity_Id; |
| Op_Type : Entity_Id := Empty) |
| is |
| Predef_Op : Entity_Id; |
| |
| begin |
| Predef_Op := Current_Entity (Selector_Name (N)); |
| while Present (Predef_Op) |
| and then Scope (Predef_Op) /= Standard_Standard |
| loop |
| Predef_Op := Homonym (Predef_Op); |
| end loop; |
| |
| if Nkind (N) = N_Selected_Component then |
| Change_Selected_Component_To_Expanded_Name (N); |
| end if; |
| |
| -- If the context is an unanalyzed function call, determine whether |
| -- a binary or unary interpretation is required. |
| |
| if Nkind (Parent (N)) = N_Indexed_Component then |
| declare |
| Is_Binary_Call : constant Boolean := |
| Present |
| (Next (First (Expressions (Parent (N))))); |
| Is_Binary_Op : constant Boolean := |
| First_Entity |
| (Predef_Op) /= Last_Entity (Predef_Op); |
| Predef_Op2 : constant Entity_Id := Homonym (Predef_Op); |
| |
| begin |
| if Is_Binary_Call then |
| if Is_Binary_Op then |
| Add_One_Interp (N, Predef_Op, T); |
| else |
| Add_One_Interp (N, Predef_Op2, T); |
| end if; |
| else |
| if not Is_Binary_Op then |
| Add_One_Interp (N, Predef_Op, T); |
| |
| -- Predef_Op2 may be empty in case of previous errors |
| |
| elsif Present (Predef_Op2) then |
| Add_One_Interp (N, Predef_Op2, T); |
| end if; |
| end if; |
| end; |
| |
| else |
| Add_One_Interp (N, Predef_Op, T); |
| |
| -- For operators with unary and binary interpretations, if |
| -- context is not a call, add both |
| |
| if Present (Homonym (Predef_Op)) then |
| Add_One_Interp (N, Homonym (Predef_Op), T); |
| end if; |
| end if; |
| |
| -- The node is a reference to a predefined operator, and |
| -- an implicit reference to the type of its operands. |
| |
| if Present (Op_Type) then |
| Generate_Operator_Reference (N, Op_Type); |
| else |
| Generate_Operator_Reference (N, T); |
| end if; |
| end Add_Implicit_Operator; |
| |
| -- Start of processing for Has_Implicit_Operator |
| |
| begin |
| if Ekind (P) = E_Package and then not In_Open_Scopes (P) then |
| Priv_Id := First_Private_Entity (P); |
| end if; |
| |
| Id := First_Entity (P); |
| |
| case Op_Id is |
| |
| -- Boolean operators: an implicit declaration exists if the scope |
| -- contains a declaration for a derived Boolean type, or for an |
| -- array of Boolean type. |
| |
| when Name_Op_And |
| | Name_Op_Not |
| | Name_Op_Or |
| | Name_Op_Xor |
| => |
| while Id /= Priv_Id loop |
| if Is_Type (Id) |
| and then Valid_Boolean_Arg (Id) |
| and then Is_Base_Type (Id) |
| then |
| Add_Implicit_Operator (Id); |
| return True; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| -- Equality: look for any non-limited type (result is Boolean) |
| |
| when Name_Op_Eq |
| | Name_Op_Ne |
| => |
| while Id /= Priv_Id loop |
| if Is_Type (Id) |
| and then Valid_Equality_Arg (Id) |
| and then Is_Base_Type (Id) |
| then |
| Add_Implicit_Operator (Standard_Boolean, Id); |
| return True; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| -- Comparison operators: scalar type, or array of scalar |
| |
| when Name_Op_Ge |
| | Name_Op_Gt |
| | Name_Op_Le |
| | Name_Op_Lt |
| => |
| while Id /= Priv_Id loop |
| if Is_Type (Id) |
| and then Valid_Comparison_Arg (Id) |
| and then Is_Base_Type (Id) |
| then |
| Add_Implicit_Operator (Standard_Boolean, Id); |
| return True; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| -- Arithmetic operators: any numeric type |
| |
| when Name_Op_Abs |
| | Name_Op_Add |
| | Name_Op_Divide |
| | Name_Op_Expon |
| | Name_Op_Mod |
| | Name_Op_Multiply |
| | Name_Op_Rem |
| | Name_Op_Subtract |
| => |
| while Id /= Priv_Id loop |
| if Is_Numeric_Type (Id) and then Is_Base_Type (Id) then |
| Add_Implicit_Operator (Id); |
| return True; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| -- Concatenation: any one-dimensional array type |
| |
| when Name_Op_Concat => |
| while Id /= Priv_Id loop |
| if Is_Array_Type (Id) |
| and then Number_Dimensions (Id) = 1 |
| and then Is_Base_Type (Id) |
| then |
| Add_Implicit_Operator (Id); |
| return True; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| -- What is the others condition here? Should we be using a |
| -- subtype of Name_Id that would restrict to operators ??? |
| |
| when others => |
| null; |
| end case; |
| |
| -- If we fall through, then we do not have an implicit operator |
| |
| return False; |
| end Has_Implicit_Operator; |
| |
| ----------------------------------- |
| -- Has_Loop_In_Inner_Open_Scopes -- |
| ----------------------------------- |
| |
| function Has_Loop_In_Inner_Open_Scopes (S : Entity_Id) return Boolean is |
| begin |
| -- Several scope stacks are maintained by Scope_Stack. The base of the |
| -- currently active scope stack is denoted by the Is_Active_Stack_Base |
| -- flag in the scope stack entry. Note that the scope stacks used to |
| -- simply be delimited implicitly by the presence of Standard_Standard |
| -- at their base, but there now are cases where this is not sufficient |
| -- because Standard_Standard actually may appear in the middle of the |
| -- active set of scopes. |
| |
| for J in reverse 0 .. Scope_Stack.Last loop |
| |
| -- S was reached without seing a loop scope first |
| |
| if Scope_Stack.Table (J).Entity = S then |
| return False; |
| |
| -- S was not yet reached, so it contains at least one inner loop |
| |
| elsif Ekind (Scope_Stack.Table (J).Entity) = E_Loop then |
| return True; |
| end if; |
| |
| -- Check Is_Active_Stack_Base to tell us when to stop, as there are |
| -- cases where Standard_Standard appears in the middle of the active |
| -- set of scopes. This affects the declaration and overriding of |
| -- private inherited operations in instantiations of generic child |
| -- units. |
| |
| pragma Assert (not Scope_Stack.Table (J).Is_Active_Stack_Base); |
| end loop; |
| |
| raise Program_Error; -- unreachable |
| end Has_Loop_In_Inner_Open_Scopes; |
| |
| -------------------- |
| -- In_Open_Scopes -- |
| -------------------- |
| |
| function In_Open_Scopes (S : Entity_Id) return Boolean is |
| begin |
| -- Several scope stacks are maintained by Scope_Stack. The base of the |
| -- currently active scope stack is denoted by the Is_Active_Stack_Base |
| -- flag in the scope stack entry. Note that the scope stacks used to |
| -- simply be delimited implicitly by the presence of Standard_Standard |
| -- at their base, but there now are cases where this is not sufficient |
| -- because Standard_Standard actually may appear in the middle of the |
| -- active set of scopes. |
| |
| for J in reverse 0 .. Scope_Stack.Last loop |
| if Scope_Stack.Table (J).Entity = S then |
| return True; |
| end if; |
| |
| -- Check Is_Active_Stack_Base to tell us when to stop, as there are |
| -- cases where Standard_Standard appears in the middle of the active |
| -- set of scopes. This affects the declaration and overriding of |
| -- private inherited operations in instantiations of generic child |
| -- units. |
| |
| exit when Scope_Stack.Table (J).Is_Active_Stack_Base; |
| end loop; |
| |
| return False; |
| end In_Open_Scopes; |
| |
| ----------------------------- |
| -- Inherit_Renamed_Profile -- |
| ----------------------------- |
| |
| procedure Inherit_Renamed_Profile (New_S : Entity_Id; Old_S : Entity_Id) is |
| New_F : Entity_Id; |
| Old_F : Entity_Id; |
| Old_T : Entity_Id; |
| New_T : Entity_Id; |
| |
| begin |
| if Ekind (Old_S) = E_Operator then |
| New_F := First_Formal (New_S); |
| |
| while Present (New_F) loop |
| Set_Etype (New_F, Base_Type (Etype (New_F))); |
| Next_Formal (New_F); |
| end loop; |
| |
| Set_Etype (New_S, Base_Type (Etype (New_S))); |
| |
| else |
| New_F := First_Formal (New_S); |
| Old_F := First_Formal (Old_S); |
| |
| while Present (New_F) loop |
| New_T := Etype (New_F); |
| Old_T := Etype (Old_F); |
| |
| -- If the new type is a renaming of the old one, as is the case |
| -- for actuals in instances, retain its name, to simplify later |
| -- disambiguation. |
| |
| if Nkind (Parent (New_T)) = N_Subtype_Declaration |
| and then Is_Entity_Name (Subtype_Indication (Parent (New_T))) |
| and then Entity (Subtype_Indication (Parent (New_T))) = Old_T |
| then |
| null; |
| else |
| Set_Etype (New_F, Old_T); |
| end if; |
| |
| Next_Formal (New_F); |
| Next_Formal (Old_F); |
| end loop; |
| |
| pragma Assert (No (Old_F)); |
| |
| if Ekind (Old_S) in E_Function | E_Enumeration_Literal then |
| Set_Etype (New_S, Etype (Old_S)); |
| end if; |
| end if; |
| end Inherit_Renamed_Profile; |
| |
| ---------------- |
| -- Initialize -- |
| ---------------- |
| |
| procedure Initialize is |
| begin |
| Urefs.Init; |
| end Initialize; |
| |
| ------------------------- |
| -- Install_Use_Clauses -- |
| ------------------------- |
| |
| procedure Install_Use_Clauses |
| (Clause : Node_Id; |
| Force_Installation : Boolean := False) |
| is |
| U : Node_Id; |
| |
| begin |
| U := Clause; |
| while Present (U) loop |
| |
| -- Case of USE package |
| |
| if Nkind (U) = N_Use_Package_Clause then |
| Use_One_Package (U, Name (U), True); |
| |
| -- Case of USE TYPE |
| |
| else |
| Use_One_Type (Subtype_Mark (U), Force => Force_Installation); |
| |
| end if; |
| |
| Next_Use_Clause (U); |
| end loop; |
| end Install_Use_Clauses; |
| |
| ---------------------- |
| -- Mark_Use_Clauses -- |
| ---------------------- |
| |
| procedure Mark_Use_Clauses (Id : Node_Or_Entity_Id) is |
| procedure Mark_Parameters (Call : Entity_Id); |
| -- Perform use_type_clause marking for all parameters in a subprogram |
| -- or operator call. |
| |
| procedure Mark_Use_Package (Pak : Entity_Id); |
| -- Move up the Prev_Use_Clause chain for packages denoted by Pak - |
| -- marking each clause in the chain as effective in the process. |
| |
| procedure Mark_Use_Type (E : Entity_Id); |
| -- Similar to Do_Use_Package_Marking except we move up the |
| -- Prev_Use_Clause chain for the type denoted by E. |
| |
| --------------------- |
| -- Mark_Parameters -- |
| --------------------- |
| |
| procedure Mark_Parameters (Call : Entity_Id) is |
| Curr : Node_Id; |
| |
| begin |
| -- Move through all of the formals |
| |
| Curr := First_Formal (Call); |
| while Present (Curr) loop |
| Mark_Use_Type (Curr); |
| |
| Next_Formal (Curr); |
| end loop; |
| |
| -- Handle the return type |
| |
| Mark_Use_Type (Call); |
| end Mark_Parameters; |
| |
| ---------------------- |
| -- Mark_Use_Package -- |
| ---------------------- |
| |
| procedure Mark_Use_Package (Pak : Entity_Id) is |
| Curr : Node_Id; |
| |
| begin |
| -- Ignore cases where the scope of the type is not a package (e.g. |
| -- Standard_Standard). |
| |
| if Ekind (Pak) /= E_Package then |
| return; |
| end if; |
| |
| Curr := Current_Use_Clause (Pak); |
| while Present (Curr) |
| and then not Is_Effective_Use_Clause (Curr) |
| loop |
| -- We need to mark the previous use clauses as effective, but |
| -- each use clause may in turn render other use_package_clauses |
| -- effective. Additionally, it is possible to have a parent |
| -- package renamed as a child of itself so we must check the |
| -- prefix entity is not the same as the package we are marking. |
| |
| if Nkind (Name (Curr)) /= N_Identifier |
| and then Present (Prefix (Name (Curr))) |
| and then Entity (Prefix (Name (Curr))) /= Pak |
| then |
| Mark_Use_Package (Entity (Prefix (Name (Curr)))); |
| |
| -- It is also possible to have a child package without a prefix |
| -- that relies on a previous use_package_clause. |
| |
| elsif Nkind (Name (Curr)) = N_Identifier |
| and then Is_Child_Unit (Entity (Name (Curr))) |
| then |
| Mark_Use_Package (Scope (Entity (Name (Curr)))); |
| end if; |
| |
| -- Mark the use_package_clause as effective and move up the chain |
| |
| Set_Is_Effective_Use_Clause (Curr); |
| |
| Curr := Prev_Use_Clause (Curr); |
| end loop; |
| end Mark_Use_Package; |
| |
| ------------------- |
| -- Mark_Use_Type -- |
| ------------------- |
| |
| procedure Mark_Use_Type (E : Entity_Id) is |
| Curr : Node_Id; |
| Base : Entity_Id; |
| |
| begin |
| -- Ignore void types and unresolved string literals and primitives |
| |
| if Nkind (E) = N_String_Literal |
| or else Nkind (Etype (E)) not in N_Entity |
| or else not Is_Type (Etype (E)) |
| then |
| return; |
| end if; |
| |
| -- Primitives with class-wide operands might additionally render |
| -- their base type's use_clauses effective - so do a recursive check |
| -- here. |
| |
| Base := Base_Type (Etype (E)); |
| |
| if Ekind (Base) = E_Class_Wide_Type then |
| Mark_Use_Type (Base); |
| end if; |
| |
| -- The package containing the type or operator function being used |
| -- may be in use as well, so mark any use_package_clauses for it as |
| -- effective. There are also additional sanity checks performed here |
| -- for ignoring previous errors. |
| |
| Mark_Use_Package (Scope (Base)); |
| |
| if Nkind (E) in N_Op |
| and then Present (Entity (E)) |
| and then Present (Scope (Entity (E))) |
| then |
| Mark_Use_Package (Scope (Entity (E))); |
| end if; |
| |
| Curr := Current_Use_Clause (Base); |
| while Present (Curr) |
| and then not Is_Effective_Use_Clause (Curr) |
| loop |
| -- Current use_type_clause may render other use_package_clauses |
| -- effective. |
| |
| if Nkind (Subtype_Mark (Curr)) /= N_Identifier |
| and then Present (Prefix (Subtype_Mark (Curr))) |
| then |
| Mark_Use_Package (Entity (Prefix (Subtype_Mark (Curr)))); |
| end if; |
| |
| -- Mark the use_type_clause as effective and move up the chain |
| |
| Set_Is_Effective_Use_Clause (Curr); |
| |
| Curr := Prev_Use_Clause (Curr); |
| end loop; |
| end Mark_Use_Type; |
| |
| -- Start of processing for Mark_Use_Clauses |
| |
| begin |
| -- Use clauses in and of themselves do not count as a "use" of a |
| -- package. |
| |
| if Nkind (Parent (Id)) in N_Use_Package_Clause | N_Use_Type_Clause then |
| return; |
| end if; |
| |
| -- Handle entities |
| |
| if Nkind (Id) in N_Entity then |
| |
| -- Mark the entity's package |
| |
| if Is_Potentially_Use_Visible (Id) then |
| Mark_Use_Package (Scope (Id)); |
| end if; |
| |
| -- Mark enumeration literals |
| |
| if Ekind (Id) = E_Enumeration_Literal then |
| Mark_Use_Type (Id); |
| |
| -- Mark primitives |
| |
| elsif (Is_Overloadable (Id) |
| or else Is_Generic_Subprogram (Id)) |
| and then (Is_Potentially_Use_Visible (Id) |
| or else Is_Intrinsic_Subprogram (Id) |
| or else (Ekind (Id) in E_Function | E_Procedure |
| and then Is_Generic_Actual_Subprogram (Id))) |
| then |
| Mark_Parameters (Id); |
| end if; |
| |
| -- Handle nodes |
| |
| else |
| -- Mark operators |
| |
| if Nkind (Id) in N_Op then |
| |
| -- At this point the left operand may not be resolved if we are |
| -- encountering multiple operators next to eachother in an |
| -- expression. |
| |
| if Nkind (Id) in N_Binary_Op |
| and then not (Nkind (Left_Opnd (Id)) in N_Op) |
| then |
| Mark_Use_Type (Left_Opnd (Id)); |
| end if; |
| |
| Mark_Use_Type (Right_Opnd (Id)); |
| Mark_Use_Type (Id); |
| |
| -- Mark entity identifiers |
| |
| elsif Nkind (Id) in N_Has_Entity |
| and then (Is_Potentially_Use_Visible (Entity (Id)) |
| or else (Is_Generic_Instance (Entity (Id)) |
| and then Is_Immediately_Visible (Entity (Id)))) |
| then |
| -- Ignore fully qualified names as they do not count as a "use" of |
| -- a package. |
| |
| if Nkind (Id) in N_Identifier | N_Operator_Symbol |
| or else (Present (Prefix (Id)) |
| and then Scope (Entity (Id)) /= Entity (Prefix (Id))) |
| then |
| Mark_Use_Clauses (Entity (Id)); |
| end if; |
| end if; |
| end if; |
| end Mark_Use_Clauses; |
| |
| -------------------------------- |
| -- Most_Descendant_Use_Clause -- |
| -------------------------------- |
| |
| function Most_Descendant_Use_Clause |
| (Clause1 : Entity_Id; |
| Clause2 : Entity_Id) return Entity_Id |
| is |
| function Determine_Package_Scope (Clause : Node_Id) return Entity_Id; |
| -- Given a use clause, determine which package it belongs to |
| |
| ----------------------------- |
| -- Determine_Package_Scope -- |
| ----------------------------- |
| |
| function Determine_Package_Scope (Clause : Node_Id) return Entity_Id is |
| begin |
| -- Check if the clause appears in the context area |
| |
| -- Note we cannot employ Enclosing_Packge for use clauses within |
| -- context clauses since they are not actually "enclosed." |
| |
| if Nkind (Parent (Clause)) = N_Compilation_Unit then |
| return Entity_Of_Unit (Unit (Parent (Clause))); |
| end if; |
| |
| -- Otherwise, obtain the enclosing package normally |
| |
| return Enclosing_Package (Clause); |
| end Determine_Package_Scope; |
| |
| Scope1 : Entity_Id; |
| Scope2 : Entity_Id; |
| |
| -- Start of processing for Most_Descendant_Use_Clause |
| |
| begin |
| if Clause1 = Clause2 then |
| return Clause1; |
| end if; |
| |
| -- We determine which one is the most descendant by the scope distance |
| -- to the ultimate parent unit. |
| |
| Scope1 := Determine_Package_Scope (Clause1); |
| Scope2 := Determine_Package_Scope (Clause2); |
| while Scope1 /= Standard_Standard |
| and then Scope2 /= Standard_Standard |
| loop |
| Scope1 := Scope (Scope1); |
| Scope2 := Scope (Scope2); |
| |
| if No (Scope1) then |
| return Clause1; |
| elsif No (Scope2) then |
| return Clause2; |
| end if; |
| end loop; |
| |
| if Scope1 = Standard_Standard then |
| return Clause1; |
| end if; |
| |
| return Clause2; |
| end Most_Descendant_Use_Clause; |
| |
| --------------- |
| -- Pop_Scope -- |
| --------------- |
| |
| procedure Pop_Scope is |
| SST : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last); |
| S : constant Entity_Id := SST.Entity; |
| |
| begin |
| if Debug_Flag_E then |
| Write_Info; |
| end if; |
| |
| -- Set Default_Storage_Pool field of the library unit if necessary |
| |
| if Is_Package_Or_Generic_Package (S) |
| and then |
| Nkind (Parent (Unit_Declaration_Node (S))) = N_Compilation_Unit |
| then |
| declare |
| Aux : constant Node_Id := |
| Aux_Decls_Node (Parent (Unit_Declaration_Node (S))); |
| begin |
| if No (Default_Storage_Pool (Aux)) then |
| Set_Default_Storage_Pool (Aux, Default_Pool); |
| end if; |
| end; |
| end if; |
| |
| Scope_Suppress := SST.Save_Scope_Suppress; |
| Local_Suppress_Stack_Top := SST.Save_Local_Suppress_Stack_Top; |
| Check_Policy_List := SST.Save_Check_Policy_List; |
| Default_Pool := SST.Save_Default_Storage_Pool; |
| No_Tagged_Streams := SST.Save_No_Tagged_Streams; |
| SPARK_Mode := SST.Save_SPARK_Mode; |
| SPARK_Mode_Pragma := SST.Save_SPARK_Mode_Pragma; |
| Default_SSO := SST.Save_Default_SSO; |
| Uneval_Old := SST.Save_Uneval_Old; |
| |
| if Debug_Flag_W then |
| Write_Str ("<-- exiting scope: "); |
| Write_Name (Chars (Current_Scope)); |
| Write_Str (", Depth="); |
| Write_Int (Int (Scope_Stack.Last)); |
| Write_Eol; |
| end if; |
| |
| End_Use_Clauses (SST.First_Use_Clause); |
| |
| -- If the actions to be wrapped are still there they will get lost |
| -- causing incomplete code to be generated. It is better to abort in |
| -- this case (and we do the abort even with assertions off since the |
| -- penalty is incorrect code generation). |
| |
| if SST.Actions_To_Be_Wrapped /= Scope_Actions'(others => No_List) then |
| raise Program_Error; |
| end if; |
| |
| -- Free last subprogram name if allocated, and pop scope |
| |
| Free (SST.Last_Subprogram_Name); |
| Scope_Stack.Decrement_Last; |
| end Pop_Scope; |
| |
| ---------------- |
| -- Push_Scope -- |
| ---------------- |
| |
| procedure Push_Scope (S : Entity_Id) is |
| E : constant Entity_Id := Scope (S); |
| |
| function Component_Alignment_Default return Component_Alignment_Kind; |
| -- Return Component_Alignment_Kind for the newly-pushed scope. |
| |
| function Component_Alignment_Default return Component_Alignment_Kind is |
| begin |
| -- Each new scope pushed onto the scope stack inherits the component |
| -- alignment of the previous scope. This emulates the "visibility" |
| -- semantics of pragma Component_Alignment. |
| |
| if Scope_Stack.Last > Scope_Stack.First then |
| return Scope_Stack.Table |
| (Scope_Stack.Last - 1).Component_Alignment_Default; |
| |
| -- Otherwise, this is the first scope being pushed on the scope |
| -- stack. Inherit the component alignment from the configuration |
| -- form of pragma Component_Alignment (if any). |
| |
| else |
| return Configuration_Component_Alignment; |
| end if; |
| end Component_Alignment_Default; |
| |
| begin |
| if Ekind (S) = E_Void then |
| null; |
| |
| -- Set scope depth if not a nonconcurrent type, and we have not yet set |
| -- the scope depth. This means that we have the first occurrence of the |
| -- scope, and this is where the depth is set. |
| |
| elsif (not Is_Type (S) or else Is_Concurrent_Type (S)) |
| and then not Scope_Depth_Set (S) |
| then |
| if S = Standard_Standard then |
| Set_Scope_Depth_Value (S, Uint_0); |
| |
| elsif Is_Child_Unit (S) then |
| Set_Scope_Depth_Value (S, Uint_1); |
| |
| elsif not Is_Record_Type (Current_Scope) then |
| if Scope_Depth_Set (Current_Scope) then |
| if Ekind (S) = E_Loop then |
| Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope)); |
| else |
| Set_Scope_Depth_Value (S, Scope_Depth (Current_Scope) + 1); |
| end if; |
| end if; |
| end if; |
| end if; |
| |
| Scope_Stack.Increment_Last; |
| |
| Scope_Stack.Table (Scope_Stack.Last) := |
| (Entity => S, |
| Save_Scope_Suppress => Scope_Suppress, |
| Save_Local_Suppress_Stack_Top => Local_Suppress_Stack_Top, |
| Save_Check_Policy_List => Check_Policy_List, |
| Save_Default_Storage_Pool => Default_Pool, |
| Save_No_Tagged_Streams => No_Tagged_Streams, |
| Save_SPARK_Mode => SPARK_Mode, |
| Save_SPARK_Mode_Pragma => SPARK_Mode_Pragma, |
| Save_Default_SSO => Default_SSO, |
| Save_Uneval_Old => Uneval_Old, |
| Component_Alignment_Default => Component_Alignment_Default, |
| Last_Subprogram_Name => null, |
| Is_Transient => False, |
| Node_To_Be_Wrapped => Empty, |
| Pending_Freeze_Actions => No_List, |
| Actions_To_Be_Wrapped => (others => No_List), |
| First_Use_Clause => Empty, |
| Is_Active_Stack_Base => False, |
| Previous_Visibility => False, |
| Locked_Shared_Objects => No_Elist); |
| |
| if Debug_Flag_W then |
| Write_Str ("--> new scope: "); |
| Write_Name (Chars (Current_Scope)); |
| Write_Str (", Id="); |
| Write_Int (Int (Current_Scope)); |
| Write_Str (", Depth="); |
| Write_Int (Int (Scope_Stack.Last)); |
| Write_Eol; |
| end if; |
| |
| -- Deal with copying flags from the previous scope to this one. This is |
| -- not necessary if either scope is standard, or if the new scope is a |
| -- child unit. |
| |
| if S /= Standard_Standard |
| and then Scope (S) /= Standard_Standard |
| and then not Is_Child_Unit (S) |
| then |
| if Nkind (E) not in N_Entity then |
| return; |
| end if; |
| |
| -- Copy categorization flags from Scope (S) to S, this is not done |
| -- when Scope (S) is Standard_Standard since propagation is from |
| -- library unit entity inwards. Copy other relevant attributes as |
| -- well (Discard_Names in particular). |
| |
| -- We only propagate inwards for library level entities, |
| -- inner level subprograms do not inherit the categorization. |
| |
| if Is_Library_Level_Entity (S) then |
| Set_Is_Preelaborated (S, Is_Preelaborated (E)); |
| Set_Is_Shared_Passive (S, Is_Shared_Passive (E)); |
| Set_Discard_Names (S, Discard_Names (E)); |
| Set_Suppress_Value_Tracking_On_Call |
| (S, Suppress_Value_Tracking_On_Call (E)); |
| Set_Categorization_From_Scope (E => S, Scop => E); |
| end if; |
| end if; |
| |
| if Is_Child_Unit (S) |
| and then Present (E) |
| and then Is_Package_Or_Generic_Package (E) |
| and then |
| Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit |
| then |
| declare |
| Aux : constant Node_Id := |
| Aux_Decls_Node (Parent (Unit_Declaration_Node (E))); |
| begin |
| if Present (Default_Storage_Pool (Aux)) then |
| Default_Pool := Default_Storage_Pool (Aux); |
| end if; |
| end; |
| end if; |
| end Push_Scope; |
| |
| --------------------- |
| -- Premature_Usage -- |
| --------------------- |
| |
| procedure Premature_Usage (N : Node_Id) is |
| Kind : constant Node_Kind := Nkind (Parent (Entity (N))); |
| E : Entity_Id := Entity (N); |
| |
| begin |
| -- Within an instance, the analysis of the actual for a formal object |
| -- does not see the name of the object itself. This is significant only |
| -- if the object is an aggregate, where its analysis does not do any |
| -- name resolution on component associations. (see 4717-008). In such a |
| -- case, look for the visible homonym on the chain. |
| |
| if In_Instance and then Present (Homonym (E)) then |
| E := Homonym (E); |
| while Present (E) and then not In_Open_Scopes (Scope (E)) loop |
| E := Homonym (E); |
| end loop; |
| |
| if Present (E) then |
| Set_Entity (N, E); |
| Set_Etype (N, Etype (E)); |
| return; |
| end if; |
| end if; |
| |
| case Kind is |
| when N_Component_Declaration => |
| Error_Msg_N |
| ("component&! cannot be used before end of record declaration", |
| N); |
| |
| when N_Parameter_Specification => |
| Error_Msg_N |
| ("formal parameter&! cannot be used before end of specification", |
| N); |
| |
| when N_Discriminant_Specification => |
| Error_Msg_N |
| ("discriminant&! cannot be used before end of discriminant part", |
| N); |
| |
| when N_Procedure_Specification | N_Function_Specification => |
| Error_Msg_N |
| ("subprogram&! cannot be used before end of its declaration", |
| N); |
| |
| when N_Full_Type_Declaration | N_Subtype_Declaration => |
| Error_Msg_N |
| ("type& cannot be used before end of its declaration!", N); |
| |
| when others => |
| Error_Msg_N |
| ("object& cannot be used before end of its declaration!", N); |
| |
| -- If the premature reference appears as the expression in its own |
| -- declaration, rewrite it to prevent compiler loops in subsequent |
| -- uses of this mangled declaration in address clauses. |
| |
| if Nkind (Parent (N)) = N_Object_Declaration then |
| Set_Entity (N, Any_Id); |
| end if; |
| end case; |
| end Premature_Usage; |
| |
| ------------------------ |
| -- Present_System_Aux -- |
| ------------------------ |
| |
| function Present_System_Aux (N : Node_Id := Empty) return Boolean is |
| Loc : Source_Ptr; |
| Aux_Name : Unit_Name_Type; |
| Unum : Unit_Number_Type; |
| Withn : Node_Id; |
| With_Sys : Node_Id; |
| The_Unit : Node_Id; |
| |
| function Find_System (C_Unit : Node_Id) return Entity_Id; |
| -- Scan context clause of compilation unit to find with_clause |
| -- for System. |
| |
| ----------------- |
| -- Find_System -- |
| ----------------- |
| |
| function Find_System (C_Unit : Node_Id) return Entity_Id is |
| With_Clause : Node_Id; |
| |
| begin |
| With_Clause := First (Context_Items (C_Unit)); |
| while Present (With_Clause) loop |
| if (Nkind (With_Clause) = N_With_Clause |
| and then Chars (Name (With_Clause)) = Name_System) |
| and then Comes_From_Source (With_Clause) |
| then |
| return With_Clause; |
| end if; |
| |
| Next (With_Clause); |
| end loop; |
| |
| return Empty; |
| end Find_System; |
| |
| -- Start of processing for Present_System_Aux |
| |
| begin |
| -- The child unit may have been loaded and analyzed already |
| |
| if Present (System_Aux_Id) then |
| return True; |
| |
| -- If no previous pragma for System.Aux, nothing to load |
| |
| elsif No (System_Extend_Unit) then |
| return False; |
| |
| -- Use the unit name given in the pragma to retrieve the unit. |
| -- Verify that System itself appears in the context clause of the |
| -- current compilation. If System is not present, an error will |
| -- have been reported already. |
| |
| else |
| With_Sys := Find_System (Cunit (Current_Sem_Unit)); |
| |
| The_Unit := Unit (Cunit (Current_Sem_Unit)); |
| |
| if No (With_Sys) |
| and then |
| (Nkind (The_Unit) = N_Package_Body |
| or else (Nkind (The_Unit) = N_Subprogram_Body |
| and then not Acts_As_Spec (Cunit (Current_Sem_Unit)))) |
| then |
| With_Sys := Find_System (Library_Unit (Cunit (Current_Sem_Unit))); |
| end if; |
| |
| if No (With_Sys) and then Present (N) then |
| |
| -- If we are compiling a subunit, we need to examine its |
| -- context as well (Current_Sem_Unit is the parent unit); |
| |
| The_Unit := Parent (N); |
| while Nkind (The_Unit) /= N_Compilation_Unit loop |
| The_Unit := Parent (The_Unit); |
| end loop; |
| |
| if Nkind (Unit (The_Unit)) = N_Subunit then |
| With_Sys := Find_System (The_Unit); |
| end if; |
| end if; |
| |
| if No (With_Sys) then |
| return False; |
| end if; |
| |
| Loc := Sloc (With_Sys); |
| Get_Name_String (Chars (Expression (System_Extend_Unit))); |
| Name_Buffer (8 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len); |
| Name_Buffer (1 .. 7) := "system."; |
| Name_Buffer (Name_Len + 8) := '%'; |
| Name_Buffer (Name_Len + 9) := 's'; |
| Name_Len := Name_Len + 9; |
| Aux_Name := Name_Find; |
| |
| Unum := |
| Load_Unit |
| (Load_Name => Aux_Name, |
| Required => False, |
| Subunit => False, |
| Error_Node => With_Sys); |
| |
| if Unum /= No_Unit then |
| Semantics (Cunit (Unum)); |
| System_Aux_Id := |
| Defining_Entity (Specification (Unit (Cunit (Unum)))); |
| |
| Withn := |
| Make_With_Clause (Loc, |
| Name => |
| Make_Expanded_Name (Loc, |
| Chars => Chars (System_Aux_Id), |
| Prefix => |
| New_Occurrence_Of (Scope (System_Aux_Id), Loc), |
| Selector_Name => New_Occurrence_Of (System_Aux_Id, Loc))); |
| |
| Set_Entity (Name (Withn), System_Aux_Id); |
| |
| Set_Corresponding_Spec (Withn, System_Aux_Id); |
| Set_First_Name (Withn); |
| Set_Implicit_With (Withn); |
| Set_Library_Unit (Withn, Cunit (Unum)); |
| |
| Insert_After (With_Sys, Withn); |
| Mark_Rewrite_Insertion (Withn); |
| Set_Context_Installed (Withn); |
| |
| return True; |
| |
| -- Here if unit load failed |
| |
| else |
| Error_Msg_Name_1 := Name_System; |
| Error_Msg_Name_2 := Chars (Expression (System_Extend_Unit)); |
| Error_Msg_N |
| ("extension package `%.%` does not exist", |
| Opt.System_Extend_Unit); |
| return False; |
| end if; |
| end if; |
| end Present_System_Aux; |
| |
| ------------------------- |
| -- Restore_Scope_Stack -- |
| ------------------------- |
| |
| procedure Restore_Scope_Stack |
| (List : Elist_Id; |
| Handle_Use : Boolean := True) |
| is |
| SS_Last : constant Int := Scope_Stack.Last; |
| Elmt : Elmt_Id; |
| |
| begin |
| -- Restore visibility of previous scope stack, if any, using the list |
| -- we saved (we use Remove, since this list will not be used again). |
| |
| loop |
| Elmt := First_Elmt (List); |
| exit when Elmt = No_Elmt; |
| Set_Is_Immediately_Visible (Node (Elmt)); |
| Remove_Elmt (List, Elmt); |
| end loop; |
| |
| -- Restore use clauses |
| |
| if SS_Last >= Scope_Stack.First |
| and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard |
| and then Handle_Use |
| then |
| Install_Use_Clauses |
| (Scope_Stack.Table (SS_Last).First_Use_Clause, |
| Force_Installation => True); |
| end if; |
| end Restore_Scope_Stack; |
| |
| ---------------------- |
| -- Save_Scope_Stack -- |
| ---------------------- |
| |
| -- Save_Scope_Stack/Restore_Scope_Stack were originally designed to avoid |
| -- consuming any memory. That is, Save_Scope_Stack took care of removing |
| -- from immediate visibility entities and Restore_Scope_Stack took care |
| -- of restoring their visibility analyzing the context of each entity. The |
| -- problem of such approach is that it was fragile and caused unexpected |
| -- visibility problems, and indeed one test was found where there was a |
| -- real problem. |
| |
| -- Furthermore, the following experiment was carried out: |
| |
| -- - Save_Scope_Stack was modified to store in an Elist1 all those |
| -- entities whose attribute Is_Immediately_Visible is modified |
| -- from True to False. |
| |
| -- - Restore_Scope_Stack was modified to store in another Elist2 |
| -- all the entities whose attribute Is_Immediately_Visible is |
| -- modified from False to True. |
| |
| -- - Extra code was added to verify that all the elements of Elist1 |
| -- are found in Elist2 |
| |
| -- This test shows that there may be more occurrences of this problem which |
| -- have not yet been detected. As a result, we replaced that approach by |
| -- the current one in which Save_Scope_Stack returns the list of entities |
| -- whose visibility is changed, and that list is passed to Restore_Scope_ |
| -- Stack to undo that change. This approach is simpler and safer, although |
| -- it consumes more memory. |
| |
| function Save_Scope_Stack (Handle_Use : Boolean := True) return Elist_Id is |
| Result : constant Elist_Id := New_Elmt_List; |
| E : Entity_Id; |
| S : Entity_Id; |
| SS_Last : constant Int := Scope_Stack.Last; |
| |
| procedure Remove_From_Visibility (E : Entity_Id); |
| -- If E is immediately visible then append it to the result and remove |
| -- it temporarily from visibility. |
| |
| ---------------------------- |
| -- Remove_From_Visibility -- |
| ---------------------------- |
| |
| procedure Remove_From_Visibility (E : Entity_Id) is |
| begin |
| if Is_Immediately_Visible (E) then |
| Append_Elmt (E, Result); |
| Set_Is_Immediately_Visible (E, False); |
| end if; |
| end Remove_From_Visibility; |
| |
| -- Start of processing for Save_Scope_Stack |
| |
| begin |
| if SS_Last >= Scope_Stack.First |
| and then Scope_Stack.Table (SS_Last).Entity /= Standard_Standard |
| then |
| if Handle_Use then |
| End_Use_Clauses (Scope_Stack.Table (SS_Last).First_Use_Clause); |
| end if; |
| |
| -- If the call is from within a compilation unit, as when called from |
| -- Rtsfind, make current entries in scope stack invisible while we |
| -- analyze the new unit. |
| |
| for J in reverse 0 .. SS_Last loop |
| exit when Scope_Stack.Table (J).Entity = Standard_Standard |
| or else No (Scope_Stack.Table (J).Entity); |
| |
| S := Scope_Stack.Table (J).Entity; |
| |
| Remove_From_Visibility (S); |
| |
| E := First_Entity (S); |
| while Present (E) loop |
| Remove_From_Visibility (E); |
| Next_Entity (E); |
| end loop; |
| end loop; |
| |
| end if; |
| |
| return Result; |
| end Save_Scope_Stack; |
| |
| ------------- |
| -- Set_Use -- |
| ------------- |
| |
| procedure Set_Use (L : List_Id) is |
| Decl : Node_Id; |
| |
| begin |
| Decl := First (L); |
| while Present (Decl) loop |
| if Nkind (Decl) = N_Use_Package_Clause then |
| Chain_Use_Clause (Decl); |
| Use_One_Package (Decl, Name (Decl)); |
| |
| elsif Nkind (Decl) = N_Use_Type_Clause then |
| Chain_Use_Clause (Decl); |
| Use_One_Type (Subtype_Mark (Decl)); |
| |
| end if; |
| |
| Next (Decl); |
| end loop; |
| end Set_Use; |
| |
| ----------------------------- |
| -- Update_Use_Clause_Chain -- |
| ----------------------------- |
| |
| procedure Update_Use_Clause_Chain is |
| |
| procedure Update_Chain_In_Scope (Level : Int); |
| -- Iterate through one level in the scope stack verifying each use-type |
| -- clause within said level is used then reset the Current_Use_Clause |
| -- to a redundant use clause outside of the current ending scope if such |
| -- a clause exists. |
| |
| --------------------------- |
| -- Update_Chain_In_Scope -- |
| --------------------------- |
| |
| procedure Update_Chain_In_Scope (Level : Int) is |
| Curr : Node_Id; |
| N : Node_Id; |
| |
| begin |
| -- Loop through all use clauses within the scope dictated by Level |
| |
| Curr := Scope_Stack.Table (Level).First_Use_Clause; |
| while Present (Curr) loop |
| |
| -- Retrieve the subtype mark or name within the current current |
| -- use clause. |
| |
| if Nkind (Curr) = N_Use_Type_Clause then |
| N := Subtype_Mark (Curr); |
| else |
| N := Name (Curr); |
| end if; |
| |
| -- If warnings for unreferenced entities are enabled and the |
| -- current use clause has not been marked effective. |
| |
| if Check_Unreferenced |
| and then Comes_From_Source (Curr) |
| and then not Is_Effective_Use_Clause (Curr) |
| and then not In_Instance |
| and then not In_Inlined_Body |
| then |
| -- We are dealing with a potentially unused use_package_clause |
| |
| if Nkind (Curr) = N_Use_Package_Clause then |
| |
| -- Renamings and formal subprograms may cause the associated |
| -- node to be marked as effective instead of the original. |
| |
| if not (Present (Associated_Node (N)) |
| and then Present |
| (Current_Use_Clause |
| (Associated_Node (N))) |
| and then Is_Effective_Use_Clause |
| (Current_Use_Clause |
| (Associated_Node (N)))) |
| then |
| Error_Msg_Node_1 := Entity (N); |
| Error_Msg_NE |
| ("use clause for package & has no effect?u?", |
| Curr, Entity (N)); |
| end if; |
| |
| -- We are dealing with an unused use_type_clause |
| |
| else |
| Error_Msg_Node_1 := Etype (N); |
| Error_Msg_NE |
| ("use clause for } has no effect?u?", Curr, Etype (N)); |
| end if; |
| end if; |
| |
| -- Verify that we haven't already processed a redundant |
| -- use_type_clause within the same scope before we move the |
| -- current use clause up to a previous one for type T. |
| |
| if Present (Prev_Use_Clause (Curr)) then |
| Set_Current_Use_Clause (Entity (N), Prev_Use_Clause (Curr)); |
| end if; |
| |
| Next_Use_Clause (Curr); |
| end loop; |
| end Update_Chain_In_Scope; |
| |
| -- Start of processing for Update_Use_Clause_Chain |
| |
| begin |
| Update_Chain_In_Scope (Scope_Stack.Last); |
| |
| -- Deal with use clauses within the context area if the current |
| -- scope is a compilation unit. |
| |
| if Is_Compilation_Unit (Current_Scope) |
| and then Sloc (Scope_Stack.Table |
| (Scope_Stack.Last - 1).Entity) = Standard_Location |
| then |
| Update_Chain_In_Scope (Scope_Stack.Last - 1); |
| end if; |
| end Update_Use_Clause_Chain; |
| |
| --------------------- |
| -- Use_One_Package -- |
| --------------------- |
| |
| procedure Use_One_Package |
| (N : Node_Id; |
| Pack_Name : Entity_Id := Empty; |
| Force : Boolean := False) |
| is |
| procedure Note_Redundant_Use (Clause : Node_Id); |
| -- Mark the name in a use clause as redundant if the corresponding |
| -- entity is already use-visible. Emit a warning if the use clause comes |
| -- from source and the proper warnings are enabled. |
| |
| ------------------------ |
| -- Note_Redundant_Use -- |
| ------------------------ |
| |
| procedure Note_Redundant_Use (Clause : Node_Id) is |
| Decl : constant Node_Id := Parent (Clause); |
| Pack_Name : constant Entity_Id := Entity (Clause); |
| |
| Cur_Use : Node_Id := Current_Use_Clause (Pack_Name); |
| Prev_Use : Node_Id := Empty; |
| Redundant : Node_Id := Empty; |
| -- The Use_Clause which is actually redundant. In the simplest case |
| -- it is Pack itself, but when we compile a body we install its |
| -- context before that of its spec, in which case it is the |
| -- use_clause in the spec that will appear to be redundant, and we |
| -- want the warning to be placed on the body. Similar complications |
| -- appear when the redundancy is between a child unit and one of its |
| -- ancestors. |
| |
| begin |
| -- Could be renamed... |
| |
| if No (Cur_Use) then |
| Cur_Use := Current_Use_Clause (Renamed_Entity (Pack_Name)); |
| end if; |
| |
| Set_Redundant_Use (Clause, True); |
| |
| -- Do not check for redundant use if clause is generated, or in an |
| -- instance, or in a predefined unit to avoid misleading warnings |
| -- that may occur as part of a rtsfind load. |
| |
| if not Comes_From_Source (Clause) |
| or else In_Instance |
| or else not Warn_On_Redundant_Constructs |
| or else Is_Predefined_Unit (Current_Sem_Unit) |
| then |
| return; |
| end if; |
| |
| if not Is_Compilation_Unit (Current_Scope) then |
| |
| -- If the use_clause is in an inner scope, it is made redundant by |
| -- some clause in the current context, with one exception: If we |
| -- are compiling a nested package body, and the use_clause comes |
| -- from then corresponding spec, the clause is not necessarily |
| -- fully redundant, so we should not warn. If a warning was |
| -- warranted, it would have been given when the spec was |
| -- processed. |
| |
| if Nkind (Parent (Decl)) = N_Package_Specification then |
| declare |
| Package_Spec_Entity : constant Entity_Id := |
| Defining_Unit_Name (Parent (Decl)); |
| begin |
| if In_Package_Body (Package_Spec_Entity) then |
| return; |
| end if; |
| end; |
| end if; |
| |
| Redundant := Clause; |
| Prev_Use := Cur_Use; |
| |
| elsif Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then |
| declare |
| Cur_Unit : constant Unit_Number_Type := |
| Get_Source_Unit (Cur_Use); |
| New_Unit : constant Unit_Number_Type := |
| Get_Source_Unit (Clause); |
| |
| Scop : Entity_Id; |
| |
| begin |
| if Cur_Unit = New_Unit then |
| |
| -- Redundant clause in same body |
| |
| Redundant := Clause; |
| Prev_Use := Cur_Use; |
| |
| elsif Cur_Unit = Current_Sem_Unit then |
| |
| -- If the new clause is not in the current unit it has been |
| -- analyzed first, and it makes the other one redundant. |
| -- However, if the new clause appears in a subunit, Cur_Unit |
| -- is still the parent, and in that case the redundant one |
| -- is the one appearing in the subunit. |
| |
| if Nkind (Unit (Cunit (New_Unit))) = N_Subunit then |
| Redundant := Clause; |
| Prev_Use := Cur_Use; |
| |
| -- Most common case: redundant clause in body, original |
| -- clause in spec. Current scope is spec entity. |
| |
| elsif Current_Scope = Cunit_Entity (Current_Sem_Unit) then |
| Redundant := Cur_Use; |
| Prev_Use := Clause; |
| |
| else |
| -- The new clause may appear in an unrelated unit, when |
| -- the parents of a generic are being installed prior to |
| -- instantiation. In this case there must be no warning. |
| -- We detect this case by checking whether the current |
| -- top of the stack is related to the current |
| -- compilation. |
| |
| Scop := Current_Scope; |
| while Present (Scop) |
| and then Scop /= Standard_Standard |
| loop |
| if Is_Compilation_Unit (Scop) |
| and then not Is_Child_Unit (Scop) |
| then |
| return; |
| |
| elsif Scop = Cunit_Entity (Current_Sem_Unit) then |
| exit; |
| end if; |
| |
| Scop := Scope (Scop); |
| end loop; |
| |
| Redundant := Cur_Use; |
| Prev_Use := Clause; |
| end if; |
| |
| elsif New_Unit = Current_Sem_Unit then |
| Redundant := Clause; |
| Prev_Use := Cur_Use; |
| |
| else |
| -- Neither is the current unit, so they appear in parent or |
| -- sibling units. Warning will be emitted elsewhere. |
| |
| return; |
| end if; |
| end; |
| |
| elsif Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Declaration |
| and then Present (Parent_Spec (Unit (Cunit (Current_Sem_Unit)))) |
| then |
| -- Use_clause is in child unit of current unit, and the child unit |
| -- appears in the context of the body of the parent, so it has |
| -- been installed first, even though it is the redundant one. |
| -- Depending on their placement in the context, the visible or the |
| -- private parts of the two units, either might appear as |
| -- redundant, but the message has to be on the current unit. |
| |
| if Get_Source_Unit (Cur_Use) = Current_Sem_Unit then |
| Redundant := Cur_Use; |
| Prev_Use := Clause; |
| else |
| Redundant := Clause; |
| Prev_Use := Cur_Use; |
| end if; |
| |
| -- If the new use clause appears in the private part of a parent |
| -- unit it may appear to be redundant w.r.t. a use clause in a |
| -- child unit, but the previous use clause was needed in the |
| -- visible part of the child, and no warning should be emitted. |
| |
| if Nkind (Parent (Decl)) = N_Package_Specification |
| and then List_Containing (Decl) = |
| Private_Declarations (Parent (Decl)) |
| then |
| declare |
| Par : constant Entity_Id := |
| Defining_Entity (Parent (Decl)); |
| Spec : constant Node_Id := |
| Specification (Unit (Cunit (Current_Sem_Unit))); |
| Cur_List : constant List_Id := List_Containing (Cur_Use); |
| |
| begin |
| if Is_Compilation_Unit (Par) |
| and then Par /= Cunit_Entity (Current_Sem_Unit) |
| then |
| if Cur_List = Context_Items (Cunit (Current_Sem_Unit)) |
| or else Cur_List = Visible_Declarations (Spec) |
| then |
| return; |
| end if; |
| end if; |
| end; |
| end if; |
| |
| -- Finally, if the current use clause is in the context then the |
| -- clause is redundant when it is nested within the unit. |
| |
| elsif Nkind (Parent (Cur_Use)) = N_Compilation_Unit |
| and then Nkind (Parent (Parent (Clause))) /= N_Compilation_Unit |
| and then Get_Source_Unit (Cur_Use) = Get_Source_Unit (Clause) |
| then |
| Redundant := Clause; |
| Prev_Use := Cur_Use; |
| end if; |
| |
| if Present (Redundant) and then Parent (Redundant) /= Prev_Use then |
| |
| -- Make sure we are looking at most-descendant use_package_clause |
| -- by traversing the chain with Find_First_Use and then verifying |
| -- there is no scope manipulation via Most_Descendant_Use_Clause. |
| |
| if Nkind (Prev_Use) = N_Use_Package_Clause |
| and then |
| (Nkind (Parent (Prev_Use)) /= N_Compilation_Unit |
| or else Most_Descendant_Use_Clause |
| (Prev_Use, Find_First_Use (Prev_Use)) /= Prev_Use) |
| then |
| Prev_Use := Find_First_Use (Prev_Use); |
| end if; |
| |
| Error_Msg_Sloc := Sloc (Prev_Use); |
| Error_Msg_NE -- CODEFIX |
| ("& is already use-visible through previous use_clause #?r?", |
| Redundant, Pack_Name); |
| end if; |
| end Note_Redundant_Use; |
| |
| -- Local variables |
| |
| Current_Instance : Entity_Id := Empty; |
| Id : Entity_Id; |
| P : Entity_Id; |
| Prev : Entity_Id; |
| Private_With_OK : Boolean := False; |
| Real_P : Entity_Id; |
| |
| -- Start of processing for Use_One_Package |
| |
| begin |
| -- Use_One_Package may have been called recursively to handle an |
| -- implicit use for a auxiliary system package, so set P accordingly |
| -- and skip redundancy checks. |
| |
| if No (Pack_Name) and then Present_System_Aux (N) then |
| P := System_Aux_Id; |
| |
| -- Check for redundant use_package_clauses |
| |
| else |
| -- Ignore cases where we are dealing with a non user defined package |
| -- like Standard_Standard or something other than a valid package. |
| |
| if not Is_Entity_Name (Pack_Name) |
| or else No (Entity (Pack_Name)) |
| or else Ekind (Entity (Pack_Name)) /= E_Package |
| then |
| return; |
| end if; |
| |
| -- When a renaming exists we must check it for redundancy. The |
| -- original package would have already been seen at this point. |
| |
| if Present (Renamed_Entity (Entity (Pack_Name))) then |
| P := Renamed_Entity (Entity (Pack_Name)); |
| else |
| P := Entity (Pack_Name); |
| end if; |
| |
| -- Check for redundant clauses then set the current use clause for |
| -- P if were are not "forcing" an installation from a scope |
| -- reinstallation that is done throughout analysis for various |
| -- reasons. |
| |
| if In_Use (P) then |
| Note_Redundant_Use (Pack_Name); |
| |
| if not Force then |
| Set_Current_Use_Clause (P, N); |
| end if; |
| |
| return; |
| |
| -- Warn about detected redundant clauses |
| |
| elsif not Force |
| and then In_Open_Scopes (P) |
| and then not Is_Hidden_Open_Scope (P) |
| then |
| if Warn_On_Redundant_Constructs and then P = Current_Scope then |
| Error_Msg_NE -- CODEFIX |
| ("& is already use-visible within itself?r?", |
| Pack_Name, P); |
| end if; |
| |
| return; |
| end if; |
| |
| -- Set P back to the non-renamed package so that visibility of the |
| -- entities within the package can be properly set below. |
| |
| P := Entity (Pack_Name); |
| end if; |
| |
| Set_In_Use (P); |
| Set_Current_Use_Clause (P, N); |
| |
| -- Ada 2005 (AI-50217): Check restriction |
| |
| if From_Limited_With (P) then |
| Error_Msg_N ("limited withed package cannot appear in use clause", N); |
| end if; |
| |
| -- Find enclosing instance, if any |
| |
| if In_Instance then |
| Current_Instance := Current_Scope; |
| while not Is_Generic_Instance (Current_Instance) loop |
| Current_Instance := Scope (Current_Instance); |
| end loop; |
| |
| if No (Hidden_By_Use_Clause (N)) then |
| Set_Hidden_By_Use_Clause (N, New_Elmt_List); |
| end if; |
| end if; |
| |
| -- If unit is a package renaming, indicate that the renamed package is |
| -- also in use (the flags on both entities must remain consistent, and a |
| -- subsequent use of either of them should be recognized as redundant). |
| |
| if Present (Renamed_Entity (P)) then |
| Set_In_Use (Renamed_Entity (P)); |
| Set_Current_Use_Clause (Renamed_Entity (P), N); |
| Real_P := Renamed_Entity (P); |
| else |
| Real_P := P; |
| end if; |
| |
| -- Ada 2005 (AI-262): Check the use_clause of a private withed package |
| -- found in the private part of a package specification |
| |
| if In_Private_Part (Current_Scope) |
| and then Has_Private_With (P) |
| and then Is_Child_Unit (Current_Scope) |
| and then Is_Child_Unit (P) |
| and then Is_Ancestor_Package (Scope (Current_Scope), P) |
| then |
| Private_With_OK := True; |
| end if; |
| |
| -- Loop through entities in one package making them potentially |
| -- use-visible. |
| |
| Id := First_Entity (P); |
| while Present (Id) |
| and then (Id /= First_Private_Entity (P) |
| or else Private_With_OK) -- Ada 2005 (AI-262) |
| loop |
| Prev := Current_Entity (Id); |
| while Present (Prev) loop |
| if Is_Immediately_Visible (Prev) |
| and then (not Is_Overloadable (Prev) |
| or else not Is_Overloadable (Id) |
| or else (Type_Conformant (Id, Prev))) |
| then |
| if No (Current_Instance) then |
| |
| -- Potentially use-visible entity remains hidden |
| |
| if Warn_On_Hiding then |
| Warn_On_Hiding_Entity (N, Hidden => Id, Visible => Prev, |
| On_Use_Clause => True); |
| end if; |
| |
| goto Next_Usable_Entity; |
| |
| -- A use clause within an instance hides outer global entities, |
| -- which are not used to resolve local entities in the |
| -- instance. Note that the predefined entities in Standard |
| -- could not have been hidden in the generic by a use clause, |
| -- and therefore remain visible. Other compilation units whose |
| -- entities appear in Standard must be hidden in an instance. |
| |
| -- To determine whether an entity is external to the instance |
| -- we compare the scope depth of its scope with that of the |
| -- current instance. However, a generic actual of a subprogram |
| -- instance is declared in the wrapper package but will not be |
| -- hidden by a use-visible entity. similarly, an entity that is |
| -- declared in an enclosing instance will not be hidden by an |
| -- an entity declared in a generic actual, which can only have |
| -- been use-visible in the generic and will not have hidden the |
| -- entity in the generic parent. |
| |
| -- If Id is called Standard, the predefined package with the |
| -- same name is in the homonym chain. It has to be ignored |
| -- because it has no defined scope (being the only entity in |
| -- the system with this mandated behavior). |
| |
| elsif not Is_Hidden (Id) |
| and then Present (Scope (Prev)) |
| and then not Is_Wrapper_Package (Scope (Prev)) |
| and then Scope_Depth (Scope (Prev)) < |
| Scope_Depth (Current_Instance) |
| and then (Scope (Prev) /= Standard_Standard |
| or else Sloc (Prev) > Standard_Location) |
| then |
| if In_Open_Scopes (Scope (Prev)) |
| and then Is_Generic_Instance (Scope (Prev)) |
| and then Present (Associated_Formal_Package (P)) |
| then |
| null; |
| |
| else |
| Set_Is_Potentially_Use_Visible (Id); |
| Set_Is_Immediately_Visible (Prev, False); |
| Append_Elmt (Prev, Hidden_By_Use_Clause (N)); |
| end if; |
| end if; |
| |
| -- A user-defined operator is not use-visible if the predefined |
| -- operator for the type is immediately visible, which is the case |
| -- if the type of the operand is in an open scope. This does not |
| -- apply to user-defined operators that have operands of different |
| -- types, because the predefined mixed mode operations (multiply |
| -- and divide) apply to universal types and do not hide anything. |
| |
| elsif Ekind (Prev) = E_Operator |
| and then Operator_Matches_Spec (Prev, Id) |
| and then In_Open_Scopes |
| (Scope (Base_Type (Etype (First_Formal (Id))))) |
| and then (No (Next_Formal (First_Formal (Id))) |
| or else Etype (First_Formal (Id)) = |
| Etype (Next_Formal (First_Formal (Id))) |
| or else Chars (Prev) = Name_Op_Expon) |
| then |
| goto Next_Usable_Entity; |
| |
| -- In an instance, two homonyms may become use_visible through the |
| -- actuals of distinct formal packages. In the generic, only the |
| -- current one would have been visible, so make the other one |
| -- not use_visible. |
| |
| -- In certain pathological cases it is possible that unrelated |
| -- homonyms from distinct formal packages may exist in an |
| -- uninstalled scope. We must test for that here. |
| |
| elsif Present (Current_Instance) |
| and then Is_Potentially_Use_Visible (Prev) |
| and then not Is_Overloadable (Prev) |
| and then Scope (Id) /= Scope (Prev) |
| and then Used_As_Generic_Actual (Scope (Prev)) |
| and then Used_As_Generic_Actual (Scope (Id)) |
| and then Is_List_Member (Scope (Prev)) |
| and then not In_Same_List (Current_Use_Clause (Scope (Prev)), |
| Current_Use_Clause (Scope (Id))) |
| then |
| Set_Is_Potentially_Use_Visible (Prev, False); |
| Append_Elmt (Prev, Hidden_By_Use_Clause (N)); |
| end if; |
| |
| Prev := Homonym (Prev); |
| end loop; |
| |
| -- On exit, we know entity is not hidden, unless it is private |
| |
| if not Is_Hidden (Id) |
| and then ((not Is_Child_Unit (Id)) or else Is_Visible_Lib_Unit (Id)) |
| then |
| Set_Is_Potentially_Use_Visible (Id); |
| |
| if Is_Private_Type (Id) and then Present (Full_View (Id)) then |
| Set_Is_Potentially_Use_Visible (Full_View (Id)); |
| end if; |
| end if; |
| |
| <<Next_Usable_Entity>> |
| Next_Entity (Id); |
| end loop; |
| |
| -- Child units are also made use-visible by a use clause, but they may |
| -- appear after all visible declarations in the parent entity list. |
| |
| while Present (Id) loop |
| if Is_Child_Unit (Id) and then Is_Visible_Lib_Unit (Id) then |
| Set_Is_Potentially_Use_Visible (Id); |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| |
| if Chars (Real_P) = Name_System |
| and then Scope (Real_P) = Standard_Standard |
| and then Present_System_Aux (N) |
| then |
| Use_One_Package (N); |
| end if; |
| end Use_One_Package; |
| |
| ------------------ |
| -- Use_One_Type -- |
| ------------------ |
| |
| procedure Use_One_Type |
| (Id : Node_Id; |
| Installed : Boolean := False; |
| Force : Boolean := False) |
| is |
| function Spec_Reloaded_For_Body return Boolean; |
| -- Determine whether the compilation unit is a package body and the use |
| -- type clause is in the spec of the same package. Even though the spec |
| -- was analyzed first, its context is reloaded when analysing the body. |
| |
| procedure Use_Class_Wide_Operations (Typ : Entity_Id); |
| -- AI05-150: if the use_type_clause carries the "all" qualifier, |
| -- class-wide operations of ancestor types are use-visible if the |
| -- ancestor type is visible. |
| |
| ---------------------------- |
| -- Spec_Reloaded_For_Body -- |
| ---------------------------- |
| |
| function Spec_Reloaded_For_Body return Boolean is |
| begin |
| if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then |
| declare |
| Spec : constant Node_Id := |
| Parent (List_Containing (Parent (Id))); |
| |
| begin |
| -- Check whether type is declared in a package specification, |
| -- and current unit is the corresponding package body. The |
| -- use clauses themselves may be within a nested package. |
| |
| return |
| Nkind (Spec) = N_Package_Specification |
| and then In_Same_Source_Unit |
| (Corresponding_Body (Parent (Spec)), |
| Cunit_Entity (Current_Sem_Unit)); |
| end; |
| end if; |
| |
| return False; |
| end Spec_Reloaded_For_Body; |
| |
| ------------------------------- |
| -- Use_Class_Wide_Operations -- |
| ------------------------------- |
| |
| procedure Use_Class_Wide_Operations (Typ : Entity_Id) is |
| function Is_Class_Wide_Operation_Of |
| (Op : Entity_Id; |
| T : Entity_Id) return Boolean; |
| -- Determine whether a subprogram has a class-wide parameter or |
| -- result that is T'Class. |
| |
| --------------------------------- |
| -- Is_Class_Wide_Operation_Of -- |
| --------------------------------- |
| |
| function Is_Class_Wide_Operation_Of |
| (Op : Entity_Id; |
| T : Entity_Id) return Boolean |
| is |
| Formal : Entity_Id; |
| |
| begin |
| Formal := First_Formal (Op); |
| while Present (Formal) loop |
| if Etype (Formal) = Class_Wide_Type (T) then |
| return True; |
| end if; |
| |
| Next_Formal (Formal); |
| end loop; |
| |
| if Etype (Op) = Class_Wide_Type (T) then |
| return True; |
| end if; |
| |
| return False; |
| end Is_Class_Wide_Operation_Of; |
| |
| -- Local variables |
| |
| Ent : Entity_Id; |
| Scop : Entity_Id; |
| |
| -- Start of processing for Use_Class_Wide_Operations |
| |
| begin |
| Scop := Scope (Typ); |
| if not Is_Hidden (Scop) then |
| Ent := First_Entity (Scop); |
| while Present (Ent) loop |
| if Is_Overloadable (Ent) |
| and then Is_Class_Wide_Operation_Of (Ent, Typ) |
| and then not Is_Potentially_Use_Visible (Ent) |
| then |
| Set_Is_Potentially_Use_Visible (Ent); |
| Append_Elmt (Ent, Used_Operations (Parent (Id))); |
| end if; |
| |
| Next_Entity (Ent); |
| end loop; |
| end if; |
| |
| if Is_Derived_Type (Typ) then |
| Use_Class_Wide_Operations (Etype (Base_Type (Typ))); |
| end if; |
| end Use_Class_Wide_Operations; |
| |
| -- Local variables |
| |
| Elmt : Elmt_Id; |
| Is_Known_Used : Boolean; |
| Op_List : Elist_Id; |
| T : Entity_Id; |
| |
| -- Start of processing for Use_One_Type |
| |
| begin |
| if Entity (Id) = Any_Type then |
| return; |
| end if; |
| |
| -- It is the type determined by the subtype mark (8.4(8)) whose |
| -- operations become potentially use-visible. |
| |
| T := Base_Type (Entity (Id)); |
| |
| -- Either the type itself is used, the package where it is declared is |
| -- in use or the entity is declared in the current package, thus |
| -- use-visible. |
| |
| Is_Known_Used := |
| (In_Use (T) |
| and then ((Present (Current_Use_Clause (T)) |
| and then All_Present (Current_Use_Clause (T))) |
| or else not All_Present (Parent (Id)))) |
| or else In_Use (Scope (T)) |
| or else Scope (T) = Current_Scope; |
| |
| Set_Redundant_Use (Id, |
| Is_Known_Used or else Is_Potentially_Use_Visible (T)); |
| |
| if Ekind (T) = E_Incomplete_Type then |
| Error_Msg_N ("premature usage of incomplete type", Id); |
| |
| elsif In_Open_Scopes (Scope (T)) then |
| null; |
| |
| -- A limited view cannot appear in a use_type_clause. However, an access |
| -- type whose designated type is limited has the flag but is not itself |
| -- a limited view unless we only have a limited view of its enclosing |
| -- package. |
| |
| elsif From_Limited_With (T) and then From_Limited_With (Scope (T)) then |
| Error_Msg_N |
| ("incomplete type from limited view cannot appear in use clause", |
| Id); |
| |
| -- If the use clause is redundant, Used_Operations will usually be |
| -- empty, but we need to set it to empty here in one case: If we are |
| -- instantiating a generic library unit, then we install the ancestors |
| -- of that unit in the scope stack, which involves reprocessing use |
| -- clauses in those ancestors. Such a use clause will typically have a |
| -- nonempty Used_Operations unless it was redundant in the generic unit, |
| -- even if it is redundant at the place of the instantiation. |
| |
| elsif Redundant_Use (Id) then |
| Set_Used_Operations (Parent (Id), New_Elmt_List); |
| |
| -- If the subtype mark designates a subtype in a different package, |
| -- we have to check that the parent type is visible, otherwise the |
| -- use_type_clause is a no-op. Not clear how to do that??? |
| |
| else |
| Set_Current_Use_Clause (T, Parent (Id)); |
| Set_In_Use (T); |
| |
| -- If T is tagged, primitive operators on class-wide operands are |
| -- also deemed available. Note that this is really necessary only |
| -- in semantics-only mode, because the primitive operators are not |
| -- fully constructed in this mode, but we do it in all modes for the |
| -- sake of uniformity, as this should not matter in practice. |
| |
| if Is_Tagged_Type (T) then |
| Set_In_Use (Class_Wide_Type (T)); |
| end if; |
| |
| -- Iterate over primitive operations of the type. If an operation is |
| -- already use_visible, it is the result of a previous use_clause, |
| -- and already appears on the corresponding entity chain. If the |
| -- clause is being reinstalled, operations are already use-visible. |
| |
| if Installed then |
| null; |
| |
| else |
| Op_List := Collect_Primitive_Operations (T); |
| Elmt := First_Elmt (Op_List); |
| while Present (Elmt) loop |
| if (Nkind (Node (Elmt)) = N_Defining_Operator_Symbol |
| or else Chars (Node (Elmt)) in Any_Operator_Name) |
| and then not Is_Hidden (Node (Elmt)) |
| and then not Is_Potentially_Use_Visible (Node (Elmt)) |
| then |
| Set_Is_Potentially_Use_Visible (Node (Elmt)); |
| Append_Elmt (Node (Elmt), Used_Operations (Parent (Id))); |
| |
| elsif Ada_Version >= Ada_2012 |
| and then All_Present (Parent (Id)) |
| and then not Is_Hidden (Node (Elmt)) |
| and then not Is_Potentially_Use_Visible (Node (Elmt)) |
| then |
| Set_Is_Potentially_Use_Visible (Node (Elmt)); |
| Append_Elmt (Node (Elmt), Used_Operations (Parent (Id))); |
| end if; |
| |
| Next_Elmt (Elmt); |
| end loop; |
| end if; |
| |
| if Ada_Version >= Ada_2012 |
| and then All_Present (Parent (Id)) |
| and then Is_Tagged_Type (T) |
| then |
| Use_Class_Wide_Operations (T); |
| end if; |
| end if; |
| |
| -- If warning on redundant constructs, check for unnecessary WITH |
| |
| if not Force |
| and then Warn_On_Redundant_Constructs |
| and then Is_Known_Used |
| |
| -- with P; with P; use P; |
| -- package P is package X is package body X is |
| -- type T ... use P.T; |
| |
| -- The compilation unit is the body of X. GNAT first compiles the |
| -- spec of X, then proceeds to the body. At that point P is marked |
| -- as use visible. The analysis then reinstalls the spec along with |
| -- its context. The use clause P.T is now recognized as redundant, |
| -- but in the wrong context. Do not emit a warning in such cases. |
| -- Do not emit a warning either if we are in an instance, there is |
| -- no redundancy between an outer use_clause and one that appears |
| -- within the generic. |
| |
| and then not Spec_Reloaded_For_Body |
| and then not In_Instance |
| and then not In_Inlined_Body |
| then |
| -- The type already has a use clause |
| |
| if In_Use (T) then |
| |
| -- Case where we know the current use clause for the type |
| |
| if Present (Current_Use_Clause (T)) then |
| Use_Clause_Known : declare |
| Clause1 : constant Node_Id := |
| Find_First_Use (Current_Use_Clause (T)); |
| Clause2 : constant Node_Id := Parent (Id); |
| Ent1 : Entity_Id; |
| Ent2 : Entity_Id; |
| Err_No : Node_Id; |
| Unit1 : Node_Id; |
| Unit2 : Node_Id; |
| |
| -- Start of processing for Use_Clause_Known |
| |
| begin |
| -- If the unit is a subprogram body that acts as spec, the |
| -- context clause is shared with the constructed subprogram |
| -- spec. Clearly there is no redundancy. |
| |
| if Clause1 = Clause2 then |
| return; |
| end if; |
| |
| Unit1 := Unit (Enclosing_Comp_Unit_Node (Clause1)); |
| Unit2 := Unit (Enclosing_Comp_Unit_Node (Clause2)); |
| |
| -- If both clauses are on same unit, or one is the body of |
| -- the other, or one of them is in a subunit, report |
| -- redundancy on the later one. |
| |
| if Unit1 = Unit2 |
| or else Nkind (Unit1) = N_Subunit |
| or else |
| (Nkind (Unit2) in N_Package_Body | N_Subprogram_Body |
| and then Nkind (Unit1) /= Nkind (Unit2) |
| and then Nkind (Unit1) /= N_Subunit) |
| then |
| Error_Msg_Sloc := Sloc (Clause1); |
| Error_Msg_NE -- CODEFIX |
| ("& is already use-visible through previous " |
| & "use_type_clause #??", Clause2, T); |
| return; |
| end if; |
| |
| -- If there is a redundant use_type_clause in a child unit |
| -- determine which of the units is more deeply nested. If a |
| -- unit is a package instance, retrieve the entity and its |
| -- scope from the instance spec. |
| |
| Ent1 := Entity_Of_Unit (Unit1); |
| Ent2 := Entity_Of_Unit (Unit2); |
| |
| -- When the scope of both units' entities are |
| -- Standard_Standard then neither Unit1 or Unit2 are child |
| -- units - so return in that case. |
| |
| if Scope (Ent1) = Standard_Standard |
| and then Scope (Ent2) = Standard_Standard |
| then |
| return; |
| |
| -- Otherwise, determine if one of the units is not a child |
| |
| elsif Scope (Ent2) = Standard_Standard then |
| Error_Msg_Sloc := Sloc (Clause2); |
| Err_No := Clause1; |
| |
| elsif Scope (Ent1) = Standard_Standard then |
| Error_Msg_Sloc := Sloc (Id); |
| Err_No := Clause2; |
| |
| -- If both units are child units, we determine which one is |
| -- the descendant by the scope distance to the ultimate |
| -- parent unit. |
| |
| else |
| declare |
| S1 : Entity_Id; |
| S2 : Entity_Id; |
| |
| begin |
| S1 := Scope (Ent1); |
| S2 := Scope (Ent2); |
| while Present (S1) |
| and then Present (S2) |
| and then S1 /= Standard_Standard |
| and then S2 /= Standard_Standard |
| loop |
| S1 := Scope (S1); |
| S2 := Scope (S2); |
| end loop; |
| |
| if S1 = Standard_Standard then |
| Error_Msg_Sloc := Sloc (Id); |
| Err_No := Clause2; |
| else |
| Error_Msg_Sloc := Sloc (Clause2); |
| Err_No := Clause1; |
| end if; |
| end; |
| end if; |
| |
| if Parent (Id) /= Err_No then |
| if Most_Descendant_Use_Clause |
| (Err_No, Parent (Id)) = Parent (Id) |
| then |
| Error_Msg_Sloc := Sloc (Err_No); |
| Err_No := Parent (Id); |
| end if; |
| |
| Error_Msg_NE -- CODEFIX |
| ("& is already use-visible through previous " |
| & "use_type_clause #??", Err_No, Id); |
| end if; |
| end Use_Clause_Known; |
| |
| -- Here Current_Use_Clause is not set for T, so we do not have the |
| -- location information available. |
| |
| else |
| Error_Msg_NE -- CODEFIX |
| ("& is already use-visible through previous " |
| & "use_type_clause??", Id, T); |
| end if; |
| |
| -- The package where T is declared is already used |
| |
| elsif In_Use (Scope (T)) then |
| -- Due to expansion of contracts we could be attempting to issue |
| -- a spurious warning - so verify there is a previous use clause. |
| |
| if Current_Use_Clause (Scope (T)) /= |
| Find_First_Use (Current_Use_Clause (Scope (T))) |
| then |
| Error_Msg_Sloc := |
| Sloc (Find_First_Use (Current_Use_Clause (Scope (T)))); |
| Error_Msg_NE -- CODEFIX |
| ("& is already use-visible through package use clause #??", |
| Id, T); |
| end if; |
| |
| -- The current scope is the package where T is declared |
| |
| else |
| Error_Msg_Node_2 := Scope (T); |
| Error_Msg_NE -- CODEFIX |
| ("& is already use-visible inside package &??", Id, T); |
| end if; |
| end if; |
| end Use_One_Type; |
| |
| ---------------- |
| -- Write_Info -- |
| ---------------- |
| |
| procedure Write_Info is |
| Id : Entity_Id := First_Entity (Current_Scope); |
| |
| begin |
| -- No point in dumping standard entities |
| |
| if Current_Scope = Standard_Standard then |
| return; |
| end if; |
| |
| Write_Str ("========================================================"); |
| Write_Eol; |
| Write_Str (" Defined Entities in "); |
| Write_Name (Chars (Current_Scope)); |
| Write_Eol; |
| Write_Str ("========================================================"); |
| Write_Eol; |
| |
| if No (Id) then |
| Write_Str ("-- none --"); |
| Write_Eol; |
| |
| else |
| while Present (Id) loop |
| Write_Entity_Info (Id, " "); |
| Next_Entity (Id); |
| end loop; |
| end if; |
| |
| if Scope (Current_Scope) = Standard_Standard then |
| |
| -- Print information on the current unit itself |
| |
| Write_Entity_Info (Current_Scope, " "); |
| end if; |
| |
| Write_Eol; |
| end Write_Info; |
| |
| -------- |
| -- ws -- |
| -------- |
| |
| procedure ws is |
| S : Entity_Id; |
| begin |
| for J in reverse 1 .. Scope_Stack.Last loop |
| S := Scope_Stack.Table (J).Entity; |
| Write_Int (Int (S)); |
| Write_Str (" === "); |
| Write_Name (Chars (S)); |
| Write_Eol; |
| end loop; |
| end ws; |
| |
| -------- |
| -- we -- |
| -------- |
| |
| procedure we (S : Entity_Id) is |
| E : Entity_Id; |
| begin |
| E := First_Entity (S); |
| while Present (E) loop |
| Write_Int (Int (E)); |
| Write_Str (" === "); |
| Write_Name (Chars (E)); |
| Write_Eol; |
| Next_Entity (E); |
| end loop; |
| end we; |
| end Sem_Ch8; |