| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S E M . C H 8 -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2004, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 2, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- |
| -- MA 02111-1307, USA. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with Atree; use Atree; |
| with Debug; use Debug; |
| with Einfo; use Einfo; |
| with Elists; use Elists; |
| with Errout; use Errout; |
| with Exp_Util; use Exp_Util; |
| with Fname; use Fname; |
| with Freeze; use Freeze; |
| with Lib; use Lib; |
| with Lib.Load; use Lib.Load; |
| with Lib.Xref; use Lib.Xref; |
| with Namet; use Namet; |
| with Nlists; use Nlists; |
| with Nmake; use Nmake; |
| with Opt; use Opt; |
| with Output; use Output; |
| with Restrict; use Restrict; |
| with Rtsfind; use Rtsfind; |
| with Sem; use Sem; |
| with Sem_Cat; use Sem_Cat; |
| with Sem_Ch3; use Sem_Ch3; |
| with Sem_Ch4; use Sem_Ch4; |
| with Sem_Ch6; use Sem_Ch6; |
| with Sem_Ch12; use Sem_Ch12; |
| 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.CN; use Sinfo.CN; |
| with Snames; use Snames; |
| with Style; use Style; |
| with Table; |
| with Tbuild; use Tbuild; |
| with Uintp; use Uintp; |
| |
| with GNAT.Spelling_Checker; use GNAT.Spelling_Checker; |
| |
| package body Sem_Ch8 is |
| |
| ------------------------------------ |
| -- Visibility and Name Resolution -- |
| ------------------------------------ |
| |
| -- This package handles name resolution and the collection of |
| -- 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. |
| |
| function Applicable_Use (Pack_Name : Node_Id) return Boolean; |
| -- Common code to Use_One_Package and Set_Use, to determine whether |
| -- use clause must be processed. Pack_Name is an entity name that |
| -- references the package in question. |
| |
| procedure Attribute_Renaming (N : Node_Id); |
| -- Analyze renaming of attribute as function. The renaming declaration N |
| -- is rewritten as a function body that returns the attribute reference |
| -- applied to the formals of the function. |
| |
| 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 : Node_Id; |
| 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 top scope table entry. |
| |
| 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. |
| |
| procedure Find_Expanded_Name (N : Node_Id); |
| -- Selected component is known to be expanded name. Verify legality |
| -- of selector given the scope denoted by prefix. |
| |
| 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_Operator (N : Node_Id) return Boolean; |
| -- N is an expanded name whose selector is an operator name (eg P."+"). |
| -- A 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 artifact of |
| -- our implementation: 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 Is_Appropriate_For_Record (T : Entity_Id) return Boolean; |
| -- Prefix is appropriate for record if it is of a record type, or |
| -- an access to such. |
| |
| function Is_Appropriate_For_Entry_Prefix (T : Entity_Id) return Boolean; |
| -- True if it is of a task type, a protected type, or else an access |
| -- to one of these types. |
| |
| procedure Premature_Usage (N : Node_Id); |
| -- Diagnose usage of an entity before it is visible. |
| |
| procedure Use_One_Package (P : Entity_Id; N : Node_Id); |
| -- 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); |
| -- Id is the subtype mark from a use type clause. This procedure makes |
| -- the primitive operators of the type potentially use-visible. |
| |
| procedure Write_Info; |
| -- Write debugging information on entities declared in current scope |
| |
| procedure Write_Scopes; |
| pragma Warnings (Off, Write_Scopes); |
| -- Debugging information: dump all entities on scope stack |
| |
| -------------------------------- |
| -- 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 Node_Id := Defining_Identifier (N); |
| Nam : constant Node_Id := Name (N); |
| |
| begin |
| Enter_Name (Id); |
| Analyze (Nam); |
| |
| Set_Ekind (Id, E_Exception); |
| Set_Exception_Code (Id, Uint_0); |
| Set_Etype (Id, Standard_Exception_Type); |
| Set_Is_Pure (Id, Is_Pure (Current_Scope)); |
| |
| if not Is_Entity_Name (Nam) or else |
| Ekind (Entity (Nam)) /= E_Exception |
| then |
| Error_Msg_N ("invalid exception name in renaming", Nam); |
| else |
| if Present (Renamed_Object (Entity (Nam))) then |
| Set_Renamed_Object (Id, Renamed_Object (Entity (Nam))); |
| else |
| Set_Renamed_Object (Id, Entity (Nam)); |
| end if; |
| 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. |
| -- For completeness, analyze prefix as well. |
| |
| 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; |
| |
| Analyze (Prefix (N)); |
| return; |
| else |
| Find_Expanded_Name (N); |
| end if; |
| 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 |
| -- Apply the Text_IO Kludge here, since we may be renaming |
| -- one of the subpackages of Text_IO, then join common routine. |
| |
| Text_IO_Kludge (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); |
| Old_P : Entity_Id; |
| Inst : Boolean := False; -- prevent junk warning |
| |
| 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); |
| Set_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_Object (Old_P)) then |
| Set_Renamed_Object (New_P, Renamed_Object (Old_P)); |
| else |
| Set_Renamed_Object (New_P, Old_P); |
| end if; |
| |
| 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; |
| |
| Check_Library_Unit_Renaming (N, Old_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); |
| Dec : Node_Id; |
| Nam : constant Node_Id := Name (N); |
| S : constant Entity_Id := Subtype_Mark (N); |
| T : Entity_Id; |
| T2 : Entity_Id; |
| |
| 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 |
| 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; |
| |
| else |
| Find_Type (S); |
| T := Entity (S); |
| Analyze_And_Resolve (Nam, T); |
| end if; |
| |
| -- 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; |
| |
| T2 := Etype (Nam); |
| Set_Ekind (Id, E_Variable); |
| Init_Size_Align (Id); |
| |
| if T = Any_Type or else Etype (Nam) = Any_Type then |
| return; |
| |
| -- Verify that the renamed entity is an object or a function call. |
| -- It may have been rewritten in several ways. |
| |
| elsif Is_Object_Reference (Nam) then |
| if Comes_From_Source (N) |
| and then Is_Dependent_Component_Of_Mutable_Object (Nam) |
| then |
| Error_Msg_N |
| ("illegal renaming of discriminant-dependent component", Nam); |
| else |
| null; |
| end if; |
| |
| -- A static function call may have been folded into a literal |
| |
| elsif Nkind (Original_Node (Nam)) = N_Function_Call |
| |
| -- When expansion is disabled, attribute reference is not |
| -- rewritten as function call. Otherwise it may be rewritten |
| -- as a conversion, so check original node. |
| |
| or else (Nkind (Original_Node (Nam)) = N_Attribute_Reference |
| and then Is_Function_Attribute_Name |
| (Attribute_Name (Original_Node (Nam)))) |
| |
| -- Weird but legal, equivalent to renaming a function call. |
| |
| or else (Is_Entity_Name (Nam) |
| and then Ekind (Entity (Nam)) = E_Enumeration_Literal) |
| |
| or else (Nkind (Nam) = N_Type_Conversion |
| and then Is_Tagged_Type (Entity (Subtype_Mark (Nam)))) |
| then |
| null; |
| |
| else |
| if Nkind (Nam) = N_Type_Conversion then |
| Error_Msg_N |
| ("renaming of conversion only allowed for tagged types", Nam); |
| |
| else |
| Error_Msg_N ("expect object name in renaming", Nam); |
| end if; |
| |
| end if; |
| |
| Set_Etype (Id, T2); |
| |
| if not Is_Variable (Nam) then |
| Set_Ekind (Id, E_Constant); |
| Set_Never_Set_In_Source (Id, True); |
| Set_Is_True_Constant (Id, True); |
| end if; |
| |
| Set_Renamed_Object (Id, Nam); |
| 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; |
| |
| -- Apply Text_IO kludge here, since we may be renaming one of |
| -- the children of Text_IO |
| |
| Text_IO_Kludge (Name (N)); |
| |
| 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)); |
| |
| -- Ada0Y (AI-50217): Limited withed packages can not be renamed |
| |
| elsif Ekind (Old_P) = E_Package |
| and then From_With_Type (Old_P) |
| then |
| Error_Msg_N |
| ("limited withed package cannot be renamed", 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. |
| |
| Set_Ekind (New_P, E_Package); |
| Set_Etype (New_P, Standard_Void_Type); |
| |
| else |
| -- Entities in the old package are accessible through the |
| -- renaming entity. The simplest implementation is to have |
| -- both packages share the entity list. |
| |
| Set_Ekind (New_P, E_Package); |
| Set_Etype (New_P, Standard_Void_Type); |
| |
| if Present (Renamed_Object (Old_P)) then |
| Set_Renamed_Object (New_P, Renamed_Object (Old_P)); |
| else |
| Set_Renamed_Object (New_P, Old_P); |
| end if; |
| |
| 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 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 := First_Entity (Old_P); |
| begin |
| 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; |
| |
| 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); |
| 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); |
| end if; |
| |
| Inherit_Renamed_Profile (New_S, Old_S); |
| end if; |
| |
| Set_Convention (New_S, Convention (Old_S)); |
| Set_Has_Completion (New_S, Inside_A_Generic); |
| |
| 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_Subprogram_Renaming -- |
| --------------------------------- |
| |
| procedure Analyze_Subprogram_Renaming (N : Node_Id) is |
| Spec : constant Node_Id := Specification (N); |
| Save_83 : constant Boolean := Ada_83; |
| Nam : constant Node_Id := Name (N); |
| New_S : Entity_Id; |
| Old_S : Entity_Id := Empty; |
| Rename_Spec : Entity_Id; |
| Is_Actual : Boolean := False; |
| Inst_Node : Node_Id := Empty; |
| |
| 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). |
| |
| ------------------------- |
| -- 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; |
| |
| -- 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 |
| Attribute_Renaming (N); |
| return; |
| end if; |
| |
| -- Check whether this declaration corresponds to the instantiation |
| -- of a formal subprogram. This is indicated by the presence of a |
| -- Corresponding_Spec that is the instantiation declaration. |
| |
| -- 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 Present (Corresponding_Spec (N)) then |
| Is_Actual := True; |
| Inst_Node := Unit_Declaration_Node (Corresponding_Spec (N)); |
| |
| if 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); |
| New_S := Analyze_Subprogram_Specification (Spec); |
| |
| if Ekind (Entity (Nam)) = E_Operator |
| and then Box_Present (Inst_Node) |
| then |
| Old_S := Find_Renamed_Entity (N, Name (N), New_S, Is_Actual); |
| end if; |
| |
| else |
| Analyze (Nam); |
| New_S := Analyze_Subprogram_Specification (Spec); |
| end if; |
| |
| Set_Corresponding_Spec (N, Empty); |
| |
| 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 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; |
| |
| Rename_Spec := Find_Corresponding_Spec (N); |
| |
| if Present (Rename_Spec) then |
| |
| -- Renaming_As_Body. Renaming declaration is the completion of |
| -- the declaration of Rename_Spec. We will build an actual body |
| -- for it at the freezing point. |
| |
| Set_Corresponding_Spec (N, Rename_Spec); |
| Set_Corresponding_Body (Unit_Declaration_Node (Rename_Spec), New_S); |
| |
| -- The body is created when the entity is frozen. If the context |
| -- is generic, freeze_all is not invoked, so we need to indicate |
| -- that the entity has a completion. |
| |
| Set_Has_Completion (Rename_Spec, Inside_A_Generic); |
| |
| if 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); |
| |
| -- Indicate that the entity in the declaration functions like |
| -- the corresponding body, and is not a new entity. |
| |
| Set_Ekind (New_S, E_Subprogram_Body); |
| New_S := Rename_Spec; |
| |
| else |
| Generate_Definition (New_S); |
| New_Overloaded_Entity (New_S); |
| if Is_Entity_Name (Nam) |
| and then Is_Intrinsic_Subprogram (Entity (Nam)) |
| then |
| null; |
| else |
| Check_Delayed_Subprogram (New_S); |
| end if; |
| 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 Etype (Nam) = Any_Type then |
| Set_Has_Completion (New_S); |
| return; |
| |
| elsif Nkind (Nam) = N_Selected_Component then |
| |
| -- Renamed entity is an entry or protected subprogram. For those |
| -- cases an explicit body is built (at the point of freezing of |
| -- this entity) that contains a call to the renamed entity. |
| |
| Analyze_Renamed_Entry (N, New_S, Present (Rename_Spec)); |
| return; |
| |
| 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; |
| |
| elsif Nkind (Nam) = N_Indexed_Component then |
| Analyze_Renamed_Family_Member (N, New_S, Present (Rename_Spec)); |
| return; |
| |
| elsif Nkind (Nam) = N_Character_Literal then |
| Analyze_Renamed_Character (N, New_S, Present (Rename_Spec)); |
| return; |
| |
| elsif (not Is_Entity_Name (Nam) |
| and then Nkind (Nam) /= N_Operator_Symbol) |
| or else not Is_Overloadable (Entity (Nam)) |
| then |
| Error_Msg_N ("expect valid subprogram name in renaming", N); |
| return; |
| |
| end if; |
| |
| -- Most common case: subprogram renames subprogram. No body is |
| -- generated in this case, so we must indicate that the declaration |
| -- is complete as is. |
| |
| if No (Rename_Spec) then |
| Set_Has_Completion (New_S); |
| 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. |
| |
| Ada_83 := False; |
| |
| if No (Old_S) then |
| Old_S := Find_Renamed_Entity (N, Name (N), New_S, Is_Actual); |
| end if; |
| |
| if Old_S /= Any_Id then |
| |
| if Is_Actual |
| and then Box_Present (Inst_Node) |
| 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; |
| |
| -- 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); |
| end if; |
| else |
| Check_Subtype_Conformant (New_S, Old_S, Spec); |
| end if; |
| |
| Check_Frozen_Renaming (N, Rename_Spec); |
| |
| elsif Ekind (Old_S) /= E_Operator then |
| Check_Mode_Conformant (New_S, Old_S); |
| |
| if Is_Actual |
| and then Error_Posted (New_S) |
| then |
| Error_Msg_NE ("invalid actual subprogram: & #!", N, 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_Instrinsic_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; |
| |
| end if; |
| |
| if not Is_Actual |
| and then (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); |
| end if; |
| |
| Set_Convention (New_S, Convention (Old_S)); |
| Set_Is_Abstract (New_S, Is_Abstract (Old_S)); |
| 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; |
| |
| if Is_Actual then |
| Freeze_Before (N, Old_S); |
| 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 Is_Abstract (Old_S) |
| then |
| Error_Msg_N |
| ("abstract subprogram not allowed as generic actual", Nam); |
| 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; |
| |
| begin |
| F1 := First_Formal (Candidate_Renaming); |
| F2 := First_Formal (New_S); |
| |
| 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; |
| end; |
| end if; |
| end if; |
| |
| Ada_83 := Save_83; |
| 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) is |
| Pack_Name : Node_Id; |
| Pack : Entity_Id; |
| |
| -- Start of processing for Analyze_Use_Package |
| |
| begin |
| Set_Hidden_By_Use_Clause (N, No_Elist); |
| |
| -- Use clause is 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, and such packages |
| -- are never loaded by Rtsfind). |
| |
| if Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit)) |
| and then Name_Buffer (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; |
| |
| -- Chain clause to list of use clauses in current scope. |
| |
| if Nkind (Parent (N)) /= N_Compilation_Unit then |
| Chain_Use_Clause (N); |
| end if; |
| |
| -- Loop through package names to identify referenced packages |
| |
| Pack_Name := First (Names (N)); |
| |
| while Present (Pack_Name) loop |
| Analyze (Pack_Name); |
| |
| if Nkind (Parent (N)) = N_Compilation_Unit |
| and then Nkind (Pack_Name) = N_Expanded_Name |
| then |
| declare |
| Pref : Node_Id := Prefix (Pack_Name); |
| |
| begin |
| 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; |
| end if; |
| |
| Next (Pack_Name); |
| end loop; |
| |
| -- Loop through package names to mark all entities as potentially |
| -- use visible. |
| |
| Pack_Name := First (Names (N)); |
| |
| while Present (Pack_Name) loop |
| |
| if Is_Entity_Name (Pack_Name) then |
| Pack := Entity (Pack_Name); |
| |
| if Ekind (Pack) /= E_Package |
| and then Etype (Pack) /= Any_Type |
| then |
| if Ekind (Pack) = E_Generic_Package then |
| Error_Msg_N |
| ("a generic package is not allowed in a use clause", |
| Pack_Name); |
| else |
| Error_Msg_N ("& is not a usable package", Pack_Name); |
| end if; |
| |
| else |
| if Nkind (Parent (N)) = N_Compilation_Unit then |
| Check_In_Previous_With_Clause (N, Pack_Name); |
| end if; |
| |
| if Applicable_Use (Pack_Name) then |
| Use_One_Package (Pack, N); |
| end if; |
| end if; |
| end if; |
| |
| Next (Pack_Name); |
| end loop; |
| |
| end Analyze_Use_Package; |
| |
| ---------------------- |
| -- Analyze_Use_Type -- |
| ---------------------- |
| |
| procedure Analyze_Use_Type (N : Node_Id) is |
| Id : Entity_Id; |
| |
| begin |
| Set_Hidden_By_Use_Clause (N, No_Elist); |
| |
| -- Chain clause to list of use clauses in current scope. |
| |
| if Nkind (Parent (N)) /= N_Compilation_Unit then |
| Chain_Use_Clause (N); |
| end if; |
| |
| Id := First (Subtype_Marks (N)); |
| |
| while Present (Id) loop |
| Find_Type (Id); |
| |
| if Entity (Id) /= 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 (Entity (Id))) |
| and then Scope (Entity (Id)) /= System_Aux_Id |
| then |
| Check_In_Previous_With_Clause (N, Prefix (Id)); |
| end if; |
| end if; |
| end if; |
| |
| Next (Id); |
| end loop; |
| end Analyze_Use_Type; |
| |
| -------------------- |
| -- Applicable_Use -- |
| -------------------- |
| |
| function Applicable_Use (Pack_Name : Node_Id) return Boolean is |
| Pack : constant Entity_Id := Entity (Pack_Name); |
| |
| begin |
| if In_Open_Scopes (Pack) then |
| return False; |
| |
| elsif In_Use (Pack) then |
| Set_Redundant_Use (Pack_Name, True); |
| return False; |
| |
| elsif Present (Renamed_Object (Pack)) |
| and then In_Use (Renamed_Object (Pack)) |
| then |
| Set_Redundant_Use (Pack_Name, True); |
| return False; |
| |
| else |
| return True; |
| end if; |
| end Applicable_Use; |
| |
| ------------------------ |
| -- 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 singular |
| -- exception of AST_Entry (which is a real oddity, it is odd that |
| -- this can be renamed at all!) |
| |
| if not Is_Non_Empty_List (Parameter_Specifications (Spec)) then |
| if Aname /= Name_AST_Entry 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_Reference_To |
| (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 numbers |
| -- of number of 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); |
| |
| elsif |
| Aname = Name_Compose or else |
| Aname = Name_Exponent or else |
| Aname = Name_Leading_Part or else |
| Aname = Name_Pos or else |
| Aname = Name_Round or else |
| Aname = Name_Scaling or else |
| Aname = Name_Val |
| then |
| if Nkind (N) = N_Subprogram_Renaming_Declaration |
| and then Present (Corresponding_Spec (N)) |
| and then Nkind (Unit_Declaration_Node (Corresponding_Spec (N))) = |
| N_Formal_Subprogram_Declaration |
| 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; |
| |
| -- AST_Entry is an odd case. It doesn't really make much sense to |
| -- allow it to be renamed, but that's the DEC rule, so we have to |
| -- do it right. The point is that the AST_Entry call should be made |
| -- now, and what the function will return is the returned value. |
| |
| -- Note that there is no Expr_List in this case anyway |
| |
| if Aname = Name_AST_Entry then |
| |
| declare |
| Ent : Entity_Id; |
| Decl : Node_Id; |
| |
| begin |
| Ent := Make_Defining_Identifier (Loc, New_Internal_Name ('R')); |
| |
| Decl := |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Ent, |
| Object_Definition => |
| New_Occurrence_Of (RTE (RE_AST_Handler), Loc), |
| Expression => Nam, |
| Constant_Present => True); |
| |
| Set_Assignment_OK (Decl, True); |
| Insert_Action (N, Decl); |
| Attr_Node := Make_Identifier (Loc, Chars (Ent)); |
| end; |
| |
| -- For all other attributes, we rewrite the 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. |
| |
| else |
| Attr_Node := |
| Make_Attribute_Reference (Loc, |
| Prefix => Prefix (Nam), |
| Attribute_Name => Aname, |
| Expressions => Expr_List); |
| |
| Set_Must_Not_Freeze (Attr_Node); |
| Set_Must_Not_Freeze (Prefix (Nam)); |
| end if; |
| |
| -- 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 (Subtype_Mark (Spec)); |
| Rewrite (Subtype_Mark (Spec), |
| New_Reference_To (Base_Type (Entity (Subtype_Mark (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_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; |
| |
| Rewrite (N, Body_Node); |
| Analyze (N); |
| |
| Set_Etype (New_S, Base_Type (Etype (New_S))); |
| |
| -- 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. |
| |
| Set_Suppress_Elaboration_Warnings (New_S); |
| |
| end Attribute_Renaming; |
| |
| ---------------------- |
| -- Chain_Use_Clause -- |
| ---------------------- |
| |
| procedure Chain_Use_Clause (N : Node_Id) is |
| begin |
| Set_Next_Use_Clause (N, |
| Scope_Stack.Table (Scope_Stack.Last).First_Use_Clause); |
| Scope_Stack.Table (Scope_Stack.Last).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 |
| 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; |
| |
| ----------------------------------- |
| -- Check_In_Previous_With_Clause -- |
| ----------------------------------- |
| |
| procedure Check_In_Previous_With_Clause |
| (N : Node_Id; |
| Nam : Entity_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 |
| 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; |
| |
| elsif Scope (Old_E) /= Standard_Standard |
| and then not Is_Child_Unit (Old_E) |
| 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 Ekind (Old_E) = E_Package |
| or else Ekind (Old_E) = E_Generic_Package |
| 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; |
| |
| --------------- |
| -- 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; |
| |
| Outer := Homonym (Id); |
| Set_Is_Immediately_Visible (Id, False); |
| |
| 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)) = N_Protected_Definition |
| or else Nkind (Parent (Decl)) = 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_Name : Node_Id; |
| Pack : Entity_Id; |
| Id : Entity_Id; |
| Elmt : Elmt_Id; |
| |
| function Is_Primitive_Operator |
| (Op : Entity_Id; |
| F : Entity_Id) |
| return Boolean; |
| -- Check whether Op is a primitive operator of a use-visible type |
| |
| --------------------------- |
| -- Is_Primitive_Operator -- |
| --------------------------- |
| |
| function Is_Primitive_Operator |
| (Op : Entity_Id; |
| F : Entity_Id) |
| return Boolean |
| is |
| T : constant Entity_Id := Etype (F); |
| |
| begin |
| return In_Use (T) |
| and then Scope (T) = Scope (Op); |
| end Is_Primitive_Operator; |
| |
| -- Start of processing for End_Use_Package |
| |
| begin |
| Pack_Name := First (Names (N)); |
| |
| while Present (Pack_Name) loop |
| Pack := Entity (Pack_Name); |
| |
| if Ekind (Pack) = E_Package then |
| |
| if In_Open_Scopes (Pack) then |
| null; |
| |
| elsif not Redundant_Use (Pack_Name) then |
| Set_In_Use (Pack, False); |
| 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 (Id, First_Formal (Id)) |
| or else |
| (Present (Next_Formal (First_Formal (Id))) |
| and then |
| Is_Primitive_Operator |
| (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_Object (Pack)) then |
| Set_In_Use (Renamed_Object (Pack), False); |
| 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; |
| |
| Next (Pack_Name); |
| end loop; |
| |
| if Present (Hidden_By_Use_Clause (N)) then |
| Elmt := First_Elmt (Hidden_By_Use_Clause (N)); |
| |
| while Present (Elmt) loop |
| Set_Is_Immediately_Visible (Node (Elmt)); |
| Next_Elmt (Elmt); |
| 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 |
| Id : Entity_Id; |
| Op_List : Elist_Id; |
| Elmt : Elmt_Id; |
| T : Entity_Id; |
| |
| begin |
| Id := First (Subtype_Marks (N)); |
| |
| while Present (Id) loop |
| |
| -- A call to rtsfind may occur while analyzing a use_type clause, |
| -- in which case the type marks are not resolved yet, and there is |
| -- nothing to remove. |
| |
| if not Is_Entity_Name (Id) |
| or else No (Entity (Id)) |
| then |
| goto Continue; |
| end if; |
| |
| T := Entity (Id); |
| |
| if T = Any_Type 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); |
| Op_List := Collect_Primitive_Operations (T); |
| Elmt := First_Elmt (Op_List); |
| |
| while Present (Elmt) loop |
| |
| if Nkind (Node (Elmt)) = N_Defining_Operator_Symbol then |
| Set_Is_Potentially_Use_Visible (Node (Elmt), False); |
| end if; |
| |
| Next_Elmt (Elmt); |
| end loop; |
| end if; |
| |
| <<Continue>> |
| Next (Id); |
| end loop; |
| end End_Use_Type; |
| |
| ---------------------- |
| -- Find_Direct_Name -- |
| ---------------------- |
| |
| procedure Find_Direct_Name (N : Node_Id) is |
| E : Entity_Id; |
| E2 : Entity_Id; |
| Msg : Boolean; |
| |
| Inst : Entity_Id := Empty; |
| -- Enclosing instance, if any. |
| |
| Homonyms : Entity_Id; |
| -- Saves start of homonym chain |
| |
| Nvis_Entity : Boolean; |
| -- Set True to indicate that at 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. |
| |
| function From_Actual_Package (E : Entity_Id) return Boolean; |
| -- Returns true if the entity is declared in a package that is |
| -- 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. |
| |
| function Known_But_Invisible (E : Entity_Id) return Boolean; |
| -- This function determines whether 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); |
| Act : Entity_Id; |
| |
| 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 then |
| |
| -- Check for end of actuals list |
| |
| if Renamed_Object (Act) = Inst then |
| return False; |
| |
| elsif Present (Associated_Formal_Package (Act)) |
| and then Renamed_Object (Act) = Scop |
| then |
| -- Entity comes from (instance of) formal package |
| |
| return True; |
| |
| else |
| Next_Entity (Act); |
| end if; |
| |
| else |
| Next_Entity (Act); |
| end if; |
| end loop; |
| |
| return False; |
| end if; |
| end From_Actual_Package; |
| |
| ------------------------- |
| -- 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; |
| |
| -- In gnat internal mode, we consider all entities known |
| |
| elsif GNAT_Mode then |
| return True; |
| 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 Is_Internal_File_Name (Fname) 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 |
| Ent : Entity_Id; |
| Hidden : Boolean := False; |
| |
| begin |
| 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 ("multiple use clauses cause hiding!", N); |
| Hidden := True; |
| end if; |
| |
| Error_Msg_Sloc := Sloc (Ent); |
| Error_Msg_N ("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); |
| else |
| Error_Msg_N ("non-visible declaration#!", N); |
| |
| if Is_Compilation_Unit (Ent) |
| and then |
| Nkind (Parent (Parent (N))) = N_Use_Package_Clause |
| then |
| Error_Msg_NE |
| ("\possibly missing with_clause for&", N, Ent); |
| 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 |
| Get_Name_String (Chars (N)); |
| |
| declare |
| Case_Str : constant String := Name_Buffer (1 .. Name_Len); |
| 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 Case_Typ /= Standard_Character |
| and then Case_Typ /= Standard_Wide_Character |
| then |
| Lit := First_Literal (Case_Typ); |
| Get_Name_String (Chars (Lit)); |
| |
| if Chars (Lit) /= Chars (N) |
| and then Is_Bad_Spelling_Of |
| (Case_Str, Name_Buffer (1 .. Name_Len)) |
| then |
| Error_Msg_Node_2 := Lit; |
| Error_Msg_N |
| ("& is undefined, assume misspelling of &", N); |
| Rewrite (N, New_Occurrence_Of (Lit, Sloc (N))); |
| return; |
| end if; |
| |
| Lit := 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, True); |
| 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) = Name_Put or else Chars (N) = Name_Put_Line then |
| Error_Msg_N ("\possible missing with of 'Text_'I'O!", N); |
| end if; |
| |
| -- Now check for possible misspellings |
| |
| Get_Name_String (Chars (N)); |
| |
| declare |
| E : Entity_Id; |
| Ematch : Entity_Id := Empty; |
| |
| Last_Name_Id : constant Name_Id := |
| Name_Id (Nat (First_Name_Id) + |
| Name_Entries_Count - 1); |
| |
| S : constant String (1 .. Name_Len) := |
| Name_Buffer (1 .. Name_Len); |
| |
| begin |
| for N in First_Name_Id .. Last_Name_Id loop |
| E := Get_Name_Entity_Id (N); |
| |
| if Present (E) |
| and then (Is_Immediately_Visible (E) |
| or else |
| Is_Potentially_Use_Visible (E)) |
| then |
| Get_Name_String (N); |
| |
| if Is_Bad_Spelling_Of |
| (Name_Buffer (1 .. Name_Len), S) |
| then |
| Ematch := E; |
| exit; |
| end if; |
| end if; |
| end loop; |
| |
| if Present (Ematch) then |
| Error_Msg_NE ("\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. |
| |
| if not All_Errors_Mode then |
| Urefs.Increment_Last; |
| Urefs.Table (Urefs.Last).Node := N; |
| Urefs.Table (Urefs.Last).Err := Emsg; |
| Urefs.Table (Urefs.Last).Nvis := Nvis; |
| Urefs.Table (Urefs.Last).Loc := Sloc (N); |
| end if; |
| |
| Msg := True; |
| end Undefined; |
| |
| -- 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)); |
| |
| 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_Array_Type (Entyp) |
| and then Is_Packed (Entyp) |
| and then Present (Etype (N)) |
| and then Etype (N) = Packed_Array_Type (Entyp) |
| then |
| null; |
| |
| -- If not that special case, then just reset the Etype |
| |
| else |
| Set_Etype (N, Etype (Entity (N))); |
| end if; |
| end; |
| end if; |
| |
| return; |
| 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; |
| |
| return; |
| |
| -- 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 (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); |
| 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. |
| -- Special case: 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. Same if it is |
| -- declared in a local instantiation of the current instance. |
| |
| else |
| if In_Instance then |
| Inst := Current_Scope; |
| |
| -- Find current instance. |
| |
| while Present (Inst) |
| and then Inst /= Standard_Standard |
| loop |
| if Is_Generic_Instance (Inst) then |
| exit; |
| end if; |
| |
| Inst := Scope (Inst); |
| end loop; |
| |
| E2 := E; |
| |
| while Present (E2) loop |
| if From_Actual_Package (E2) |
| or else |
| (Is_Generic_Instance (Scope (E2)) |
| and then Scope_Depth (Scope (E2)) > Scope_Depth (Inst)) |
| then |
| E := E2; |
| goto Found; |
| end if; |
| |
| E2 := Homonym (E2); |
| end loop; |
| |
| Nvis_Messages; |
| return; |
| |
| else |
| Nvis_Messages; |
| return; |
| 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 a more |
| -- 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 |
| 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; |
| |
| 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 |
| |
| if Comes_From_Source (N) |
| and then Is_Remote_Access_To_Subprogram_Type (E) |
| and then Expander_Active |
| then |
| Rewrite (N, |
| New_Occurrence_Of (Equivalent_Type (E), Sloc (N))); |
| return; |
| end if; |
| |
| Set_Entity (N, E); |
| -- Why no Style_Check here??? |
| |
| 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 |
| Generate_Reference (E, N); |
| 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 |
| -- One slightly 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 |
| |
| if Nkind (Parent (N)) = N_Label then |
| declare |
| R : constant Boolean := Referenced (E); |
| |
| begin |
| Generate_Reference (E, N); |
| Set_Referenced (E, R); |
| end; |
| |
| -- Normal case, not a label. Generate reference. |
| |
| else |
| Generate_Reference (E, N); |
| end if; |
| |
| -- Set Entity, with style check if need be. If this is a |
| -- discriminant reference, it must be replaced by the |
| -- corresponding discriminal, that is to say the parameter |
| -- of the initialization procedure that corresponds to the |
| -- discriminant. If this replacement is being performed, there |
| -- is no style check to perform. |
| |
| -- This replacement must not be done if we are currently |
| -- processing a generic spec or body, because the discriminal |
| -- has not been not generated in this case. |
| |
| if not In_Default_Expression |
| or else Ekind (E) /= E_Discriminant |
| or else Inside_A_Generic |
| then |
| Set_Entity_With_Style_Check (N, E); |
| |
| -- The replacement is not done either for a task discriminant that |
| -- appears in a default expression of an entry parameter. See |
| -- Expand_Discriminant in exp_ch2 for details on their handling. |
| |
| elsif Is_Concurrent_Type (Scope (E)) then |
| declare |
| P : Node_Id := Parent (N); |
| |
| begin |
| while Present (P) |
| and then Nkind (P) /= N_Parameter_Specification |
| and then Nkind (P) /= 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; |
| end; |
| |
| -- 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 if; |
| end; |
| 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 |
| Selector : constant Node_Id := Selector_Name (N); |
| Candidate : Entity_Id := Empty; |
| P_Name : Entity_Id; |
| O_Name : Entity_Id; |
| Id : Entity_Id; |
| |
| begin |
| P_Name := Entity (Prefix (N)); |
| O_Name := P_Name; |
| |
| -- 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_Object (P_Name)) |
| then |
| P_Name := Renamed_Object (P_Name); |
| |
| -- 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); |
| |
| while Present (Id) loop |
| |
| if Scope (Id) = P_Name then |
| Candidate := Id; |
| |
| if Is_Child_Unit (Id) then |
| exit when Is_Visible_Child_Unit (Id) |
| or else Is_Immediately_Visible (Id); |
| |
| else |
| exit when not Is_Hidden (Id) |
| or else Is_Immediately_Visible (Id); |
| end if; |
| end if; |
| |
| Id := Homonym (Id); |
| end loop; |
| |
| if No (Id) |
| and then (Ekind (P_Name) = E_Procedure |
| or else |
| Ekind (P_Name) = 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; |
| |
| elsif Nkind (Selector) = N_Operator_Symbol |
| and then Has_Implicit_Operator (N) |
| then |
| -- 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. |
| |
| return; |
| |
| elsif Nkind (Selector) = N_Character_Literal |
| and then Has_Implicit_Character_Literal (N) |
| then |
| -- 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. |
| |
| 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 Is_Child_Unit (Candidate) then |
| Error_Msg_N |
| ("missing with_clause for child unit &", Selector); |
| 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. Find whether we are within |
| -- the corresponding instance, and get the proper entity, which |
| -- can only be an enclosing scope. |
| |
| if O_Name /= P_Name |
| and then In_Open_Scopes (P_Name) |
| and then Is_Generic_Instance (P_Name) |
| then |
| declare |
| 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) = E_Function |
| or else Ekind (S) = E_Package |
| or else Ekind (S) = E_Procedure |
| then |
| P := Generic_Parent (Specification |
| (Unit_Declaration_Node (S))); |
| |
| if Present (P) |
| and then Chars (Scope (P)) = Chars (O_Name) |
| and then Chars (P) = Chars (Selector) |
| then |
| Id := S; |
| goto found; |
| end if; |
| end if; |
| |
| end loop; |
| end; |
| end if; |
| |
| if Chars (P_Name) = Name_Ada |
| and then Scope (P_Name) = Standard_Standard |
| then |
| Error_Msg_Node_2 := Selector; |
| Error_Msg_NE ("missing with for `&.&`", N, P_Name); |
| |
| -- 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 |
| |
| Error_Msg_NE ("& not declared in&", N, Selector); |
| |
| -- Check for misspelling of some entity in prefix. |
| |
| Id := First_Entity (P_Name); |
| Get_Name_String (Chars (Selector)); |
| |
| declare |
| S : constant String (1 .. Name_Len) := |
| Name_Buffer (1 .. Name_Len); |
| begin |
| while Present (Id) loop |
| Get_Name_String (Chars (Id)); |
| if Is_Bad_Spelling_Of |
| (Name_Buffer (1 .. Name_Len), S) |
| and then not Is_Internal_Name (Chars (Id)) |
| then |
| Error_Msg_NE |
| ("possible misspelling of&", Selector, Id); |
| exit; |
| end if; |
| |
| Next_Entity (Id); |
| end loop; |
| end; |
| |
| -- 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_NE |
| ("\possible missing with clause on child unit&", |
| N, Selector); |
| 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) |
| then |
| Id := Equivalent_Type (Id); |
| Set_Chars (Selector, Chars (Id)); |
| end if; |
| |
| -- Ada0Y (AI-50217): Check usage of entities in limited withed units |
| |
| if Ekind (P_Name) = E_Package |
| and then From_With_Type (P_Name) |
| then |
| if From_With_Type (Id) |
| or else (Ekind (Id) = E_Package and then From_With_Type (Id)) |
| 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 |
| -- 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; |
| |
| Change_Selected_Component_To_Expanded_Name (N); |
| |
| -- 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_With_Style_Check (N, Id); |
| Generate_Reference (Id, N); |
| end if; |
| |
| if Is_Type (Id) then |
| Set_Etype (N, Id); |
| else |
| Set_Etype (N, Get_Full_View (Etype (Id))); |
| 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)). |
| |
| 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) 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; |
| end Find_Expanded_Name; |
| |
| ------------------------- |
| -- 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 Enclosing_Instance return Entity_Id; |
| -- 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 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. |
| |
| 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. |
| |
| ------------------------ |
| -- Enclosing_Instance -- |
| ------------------------ |
| |
| function Enclosing_Instance return Entity_Id is |
| S : Entity_Id; |
| |
| begin |
| if not Is_Generic_Instance (Current_Scope) |
| and then not Is_Actual |
| 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; |
| |
| -------------------------- |
| -- 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_Object (Scop)) |
| then |
| Scop := Renamed_Object (Scop); |
| end if; |
| |
| -- Operator is visible if prefix of expanded name denotes |
| -- scope of type, or else type 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 := Scope (Inner); |
| |
| begin |
| while Sc /= Standard_Standard loop |
| |
| if Sc = Outer then |
| return True; |
| else |
| Sc := Scope (Sc); |
| end if; |
| end loop; |
| |
| return False; |
| end Within; |
| |
| function Report_Overload return Entity_Id; |
| -- List possible interpretations, and specialize message in the |
| -- case of a generic actual. |
| |
| function Report_Overload return Entity_Id is |
| begin |
| if Is_Actual then |
| Error_Msg_NE |
| ("ambiguous actual subprogram&, " & |
| "possible interpretations: ", N, Nam); |
| else |
| Error_Msg_N |
| ("ambiguous subprogram, " & |
| "possible interpretations: ", N); |
| end if; |
| |
| List_Interps (Nam, N); |
| return Old_S; |
| end Report_Overload; |
| |
| -- Start of processing for Find_Renamed_Entry |
| |
| begin |
| Old_S := Any_Id; |
| Candidate_Renaming := Empty; |
| |
| if not Is_Overloaded (Nam) then |
| if Entity_Matches_Spec (Entity (Nam), New_S) |
| and then Is_Visible_Operation (Entity (Nam)) |
| then |
| Old_S := Entity (Nam); |
| |
| 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; |
| |
| else |
| 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 |
| return (It.Nam); |
| |
| elsif Within (Old_S, Inst) then |
| return (Old_S); |
| |
| else |
| return Report_Overload; |
| end if; |
| |
| 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); |
| Set_Is_Overloaded (Nam, False); |
| 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; |
| |
| begin |
| Analyze (P); |
| |
| if Nkind (P) = N_Error then |
| return; |
| |
| -- 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). |
| |
| elsif 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 |
| C_Etype := |
| Build_Actual_Subtype_Of_Component ( |
| Etype (Selector), N); |
| 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 this is the name of an entry or protected operation, and |
| -- the prefix is an access type, insert an explicit dereference, |
| -- so that entry calls are treated uniformly. |
| |
| if Is_Access_Type (Etype (P)) |
| and then Is_Concurrent_Type (Designated_Type (Etype (P))) |
| then |
| declare |
| New_P : constant Node_Id := |
| Make_Explicit_Dereference (Sloc (P), |
| Prefix => Relocate_Node (P)); |
| begin |
| Rewrite (P, New_P); |
| Set_Etype (P, Designated_Type (Etype (Prefix (P)))); |
| end; |
| end if; |
| |
| -- If the selected component appears within a default expression |
| -- and it has an actual subtype, the pre-analysis 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; |
| |
| -- First check for components of a record object (not the |
| -- result of a call, which is handled below). |
| |
| if Is_Appropriate_For_Record (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. |
| |
| Analyze_Selected_Component (N); |
| |
| elsif Is_Appropriate_For_Entry_Prefix (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. |
| |
| Find_Expanded_Name (N); |
| |
| 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) = E_Procedure |
| or else Ekind (P_Name) = 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. If the prefix is a |
| -- procedure or entry, as is P.X; this is an error. |
| |
| 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 |
| Error_Msg_Sloc := Sloc (Entity (Prefix (N))); |
| |
| Error_Msg_NE |
| ("package& is hidden by declaration#", |
| N, P_Name); |
| |
| 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); |
| |
| else |
| Nam := New_Copy (P); |
| Save_Interps (P, Nam); |
| Rewrite (P, |
| Make_Function_Call (Sloc (P), Name => Nam)); |
| Analyze_Call (P); |
| Analyze_Selected_Component (N); |
| 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; |
| |
| elsif Ekind (P_Name) = E_Void then |
| Premature_Usage (P); |
| |
| elsif Nkind (P) /= N_Attribute_Reference then |
| Error_Msg_N ( |
| "invalid prefix in selected component&", P); |
| |
| if Is_Access_Type (P_Type) |
| and then Ekind (Designated_Type (P_Type)) = E_Incomplete_Type |
| then |
| Error_Msg_N |
| ("\dereference must not be of an incomplete type " & |
| "('R'M 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; |
| 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 only valid in Ada 95 mode, but we don't |
| -- do a check, since the tagged type referenced could only exist if |
| -- we were in 95 mode when it was declared (or, if we were in Ada |
| -- 83 mode, then an error message would already have been issued). |
| |
| 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 of non-tagged type |
| |
| 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. |
| |
| Set_Is_Tagged_Type (T); |
| 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 not Present (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 |
| C := Class_Wide_Type (Entity (Prefix (N))); |
| Set_Entity_With_Style_Check (N, C); |
| Generate_Reference (C, N); |
| Set_Etype (N, C); |
| end if; |
| |
| -- Base attribute, allowed in Ada 95 mode only |
| |
| elsif Attribute_Name (N) = Name_Base then |
| if 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_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", Typ); |
| |
| elsif Sloc (Typ) = Standard_Location |
| and then Base_Type (Typ) = Typ |
| and then Warn_On_Redundant_Constructs |
| then |
| Error_Msg_NE |
| ("?redudant attribute, & is its own base type", 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 (Entity (N)), |
| Prefix => New_Copy (Prefix (Prefix (N))), |
| Selector_Name => |
| New_Reference_To (Entity (N), Sloc (N)))); |
| |
| else |
| Rewrite (N, |
| New_Reference_To (Entity (N), Sloc (N))); |
| end if; |
| |
| Set_Entity (N, T); |
| Set_Etype (N, T); |
| end if; |
| |
| -- 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 |
| T_Name := Get_Full_View (T_Name); |
| |
| if In_Open_Scopes (T_Name) then |
| if Ekind (Base_Type (T_Name)) = E_Task_Type then |
| Error_Msg_N ("task type cannot be used as type mark " & |
| "within its own body", N); |
| 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; |
| end if; |
| end Find_Type; |
| |
| ------------------- |
| -- Get_Full_View -- |
| ------------------- |
| |
| function Get_Full_View (T_Name : Entity_Id) return Entity_Id is |
| begin |
| if Ekind (T_Name) = E_Incomplete_Type |
| and then Present (Full_View (T_Name)) |
| then |
| return Full_View (T_Name); |
| |
| elsif Is_Class_Wide_Type (T_Name) |
| and then Ekind (Root_Type (T_Name)) = E_Incomplete_Type |
| and then Present (Full_View (Root_Type (T_Name))) |
| then |
| return Class_Wide_Type (Full_View (Root_Ty
|