Google Git
Sign in
gnu / gcc / a8404c07e7fca388c02c39077865f7d5fa928430 / . / gcc / ada / sem_ch7.adb
blob: 0fb9fe10ff6efdb3bd274f3945099b773b51bc0a [file] [log] [blame]
------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S E M _ C H 7 --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2022, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING3. If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package contains the routines to process package specifications and
-- bodies. The most important semantic aspects of package processing are the
-- handling of private and full declarations, and the construction of dispatch
-- tables for tagged types.
with Aspects; use Aspects;
with Atree; use Atree;
with Contracts; use Contracts;
with Debug; use Debug;
with Einfo; use Einfo;
with Einfo.Entities; use Einfo.Entities;
with Einfo.Utils; use Einfo.Utils;
with Elists; use Elists;
with Errout; use Errout;
with Exp_Disp; use Exp_Disp;
with Exp_Dist; use Exp_Dist;
with Exp_Dbug; use Exp_Dbug;
with Freeze; use Freeze;
with Ghost; use Ghost;
with Lib; use Lib;
with Lib.Xref; use Lib.Xref;
with Namet; use Namet;
with Nmake; use Nmake;
with Nlists; use Nlists;
with Opt; use Opt;
with Output; use Output;
with Rtsfind; use Rtsfind;
with Sem; use Sem;
with Sem_Aux; use Sem_Aux;
with Sem_Cat; use Sem_Cat;
with Sem_Ch3; use Sem_Ch3;
with Sem_Ch6; use Sem_Ch6;
with Sem_Ch8; use Sem_Ch8;
with Sem_Ch10; use Sem_Ch10;
with Sem_Ch12; use Sem_Ch12;
with Sem_Ch13; use Sem_Ch13;
with Sem_Disp; use Sem_Disp;
with Sem_Eval; use Sem_Eval;
with Sem_Prag; use Sem_Prag;
with Sem_Util; use Sem_Util;
with Sem_Warn; use Sem_Warn;
with Snames; use Snames;
with Stand; use Stand;
with Sinfo; use Sinfo;
with Sinfo.Nodes; use Sinfo.Nodes;
with Sinfo.Utils; use Sinfo.Utils;
with Sinput; use Sinput;
with Style;
with Uintp; use Uintp;
with Warnsw; use Warnsw;
with GNAT.HTable;
package body Sem_Ch7 is
-----------------------------------
-- 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 the 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.
-----------------------
-- Local Subprograms --
-----------------------
procedure Analyze_Package_Body_Helper (N : Node_Id);
-- Does all the real work of Analyze_Package_Body
procedure Check_Anonymous_Access_Types
(Spec_Id : Entity_Id;
P_Body : Node_Id);
-- If the spec of a package has a limited_with_clause, it may declare
-- anonymous access types whose designated type is a limited view, such an
-- anonymous access return type for a function. This access type cannot be
-- elaborated in the spec itself, but it may need an itype reference if it
-- is used within a nested scope. In that case the itype reference is
-- created at the beginning of the corresponding package body and inserted
-- before other body declarations.
procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id);
-- Called upon entering the private part of a public child package and the
-- body of a nested package, to potentially declare certain inherited
-- subprograms that were inherited by types in the visible part, but whose
-- declaration was deferred because the parent operation was private and
-- not visible at that point. These subprograms are located by traversing
-- the visible part declarations looking for non-private type extensions
-- and then examining each of the primitive operations of such types to
-- find those that were inherited but declared with a special internal
-- name. Each such operation is now declared as an operation with a normal
-- name (using the name of the parent operation) and replaces the previous
-- implicit operation in the primitive operations list of the type. If the
-- inherited private operation has been overridden, then it's replaced by
-- the overriding operation.
procedure Install_Package_Entity (Id : Entity_Id);
-- Supporting procedure for Install_{Visible,Private}_Declarations. Places
-- one entity on its visibility chain, and recurses on the visible part if
-- the entity is an inner package.
function Is_Private_Base_Type (E : Entity_Id) return Boolean;
-- True for a private type that is not a subtype
function Is_Visible_Dependent (Dep : Entity_Id) return Boolean;
-- If the private dependent is a private type whose full view is derived
-- from the parent type, its full properties are revealed only if we are in
-- the immediate scope of the private dependent. Should this predicate be
-- tightened further???
function Requires_Completion_In_Body
(Id : Entity_Id;
Pack_Id : Entity_Id;
Do_Abstract_States : Boolean := False) return Boolean;
-- Subsidiary to routines Unit_Requires_Body and Unit_Requires_Body_Info.
-- Determine whether entity Id declared in package spec Pack_Id requires
-- completion in a package body. Flag Do_Abstract_Stats should be set when
-- abstract states are to be considered in the completion test.
procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id);
-- Outputs info messages showing why package Pack_Id requires a body. The
-- caller has checked that the switch requesting this information is set,
-- and that the package does indeed require a body.
--------------------------
-- Analyze_Package_Body --
--------------------------
procedure Analyze_Package_Body (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
begin
if Debug_Flag_C then
Write_Str ("==> package body ");
Write_Name (Chars (Defining_Entity (N)));
Write_Str (" from ");
Write_Location (Loc);
Write_Eol;
Indent;
end if;
-- The real work is split out into the helper, so it can do "return;"
-- without skipping the debug output.
Analyze_Package_Body_Helper (N);
if Debug_Flag_C then
Outdent;
Write_Str ("<== package body ");
Write_Name (Chars (Defining_Entity (N)));
Write_Str (" from ");
Write_Location (Loc);
Write_Eol;
end if;
end Analyze_Package_Body;
------------------------------------------------------
-- Analyze_Package_Body_Helper Data and Subprograms --
------------------------------------------------------
Entity_Table_Size : constant := 4093;
-- Number of headers in hash table
subtype Entity_Header_Num is Integer range 0 .. Entity_Table_Size - 1;
-- Range of headers in hash table
function Node_Hash (Id : Entity_Id) return Entity_Header_Num;
-- Simple hash function for Entity_Ids
package Subprogram_Table is new GNAT.Htable.Simple_HTable
(Header_Num => Entity_Header_Num,
Element => Boolean,
No_Element => False,
Key => Entity_Id,
Hash => Node_Hash,
Equal => "=");
-- Hash table to record which subprograms are referenced. It is declared
-- at library level to avoid elaborating it for every call to Analyze.
package Traversed_Table is new GNAT.Htable.Simple_HTable
(Header_Num => Entity_Header_Num,
Element => Boolean,
No_Element => False,
Key => Node_Id,
Hash => Node_Hash,
Equal => "=");
-- Hash table to record which nodes we have traversed, so we can avoid
-- traversing the same nodes repeatedly.
-----------------
-- Node_Hash --
-----------------
function Node_Hash (Id : Entity_Id) return Entity_Header_Num is
begin
return Entity_Header_Num (Id mod Entity_Table_Size);
end Node_Hash;
---------------------------------
-- Analyze_Package_Body_Helper --
---------------------------------
-- WARNING: This routine manages Ghost regions. Return statements must be
-- replaced by gotos which jump to the end of the routine and restore the
-- Ghost mode.
procedure Analyze_Package_Body_Helper (N : Node_Id) is
procedure Hide_Public_Entities (Decls : List_Id);
-- Attempt to hide all public entities found in declarative list Decls
-- by resetting their Is_Public flag to False depending on whether the
-- entities are not referenced by inlined or generic bodies. This kind
-- of processing is a conservative approximation and will still leave
-- entities externally visible if the package is not simple enough.
procedure Install_Composite_Operations (P : Entity_Id);
-- Composite types declared in the current scope may depend on types
-- that were private at the point of declaration, and whose full view
-- is now in scope. Indicate that the corresponding operations on the
-- composite type are available.
--------------------------
-- Hide_Public_Entities --
--------------------------
procedure Hide_Public_Entities (Decls : List_Id) is
function Has_Referencer
(Decls : List_Id;
In_Nested_Instance : Boolean;
Has_Outer_Referencer_Of_Non_Subprograms : Boolean) return Boolean;
-- A "referencer" is a construct which may reference a previous
-- declaration. Examine all declarations in list Decls in reverse
-- and determine whether one such referencer exists. All entities
-- in the range Last (Decls) .. Referencer are hidden from external
-- visibility. In_Nested_Instance is true if we are inside a package
-- instance that has a body.
function Scan_Subprogram_Ref (N : Node_Id) return Traverse_Result;
-- Determine whether a node denotes a reference to a subprogram
procedure Traverse_And_Scan_Subprogram_Refs is
new Traverse_Proc (Scan_Subprogram_Ref);
-- Subsidiary to routine Has_Referencer. Determine whether a node
-- contains references to a subprogram and record them.
-- WARNING: this is a very expensive routine as it performs a full
-- tree traversal.
procedure Scan_Subprogram_Refs (Node : Node_Id);
-- If we haven't already traversed Node, then mark and traverse it.
--------------------
-- Has_Referencer --
--------------------
function Has_Referencer
(Decls : List_Id;
In_Nested_Instance : Boolean;
Has_Outer_Referencer_Of_Non_Subprograms : Boolean) return Boolean
is
Has_Referencer_Of_Non_Subprograms : Boolean :=
Has_Outer_Referencer_Of_Non_Subprograms;
-- Set if an inlined subprogram body was detected as a referencer.
-- In this case, we do not return True immediately but keep hiding
-- subprograms from external visibility.
Decl : Node_Id;
Decl_Id : Entity_Id;
In_Instance : Boolean;
Spec : Node_Id;
Ignore : Boolean;
function Set_Referencer_Of_Non_Subprograms return Boolean;
-- Set Has_Referencer_Of_Non_Subprograms and call
-- Scan_Subprogram_Refs if relevant.
-- Return whether Scan_Subprogram_Refs was called.
---------------------------------------
-- Set_Referencer_Of_Non_Subprograms --
---------------------------------------
function Set_Referencer_Of_Non_Subprograms return Boolean is
begin
-- An inlined subprogram body acts as a referencer
-- unless we generate C code since inlining is then
-- handled by the C compiler.
-- Note that we test Has_Pragma_Inline here in addition
-- to Is_Inlined. We are doing this for a client, since
-- we are computing which entities should be public, and
-- it is the client who will decide if actual inlining
-- should occur, so we need to catch all cases where the
-- subprogram may be inlined by the client.
if (not CCG_Mode or else Has_Pragma_Inline_Always (Decl_Id))
and then (Is_Inlined (Decl_Id)
or else Has_Pragma_Inline (Decl_Id))
then
Has_Referencer_Of_Non_Subprograms := True;
-- Inspect the statements of the subprogram body
-- to determine whether the body references other
-- subprograms.
Scan_Subprogram_Refs (Decl);
return True;
else
return False;
end if;
end Set_Referencer_Of_Non_Subprograms;
begin
if No (Decls) then
return False;
end if;
-- Examine all declarations in reverse order, hiding all entities
-- from external visibility until a referencer has been found. The
-- algorithm recurses into nested packages.
Decl := Last (Decls);
while Present (Decl) loop
-- A stub is always considered a referencer
if Nkind (Decl) in N_Body_Stub then
return True;
-- Package declaration
elsif Nkind (Decl) = N_Package_Declaration then
Spec := Specification (Decl);
Decl_Id := Defining_Entity (Spec);
-- Inspect the declarations of a non-generic package to try
-- and hide more entities from external visibility.
if not Is_Generic_Unit (Decl_Id) then
if In_Nested_Instance then
In_Instance := True;
elsif Is_Generic_Instance (Decl_Id) then
In_Instance :=
Has_Completion (Decl_Id)
or else Unit_Requires_Body (Generic_Parent (Spec));
else
In_Instance := False;
end if;
if Has_Referencer (Private_Declarations (Spec),
In_Instance,
Has_Referencer_Of_Non_Subprograms)
or else
Has_Referencer (Visible_Declarations (Spec),
In_Instance,
Has_Referencer_Of_Non_Subprograms)
then
return True;
end if;
end if;
-- Package body
elsif Nkind (Decl) = N_Package_Body
and then Present (Corresponding_Spec (Decl))
then
Decl_Id := Corresponding_Spec (Decl);
-- A generic package body is a referencer. It would seem
-- that we only have to consider generics that can be
-- exported, i.e. where the corresponding spec is the
-- spec of the current package, but because of nested
-- instantiations, a fully private generic body may export
-- other private body entities. Furthermore, regardless of
-- whether there was a previous inlined subprogram, (an
-- instantiation of) the generic package may reference any
-- entity declared before it.
if Is_Generic_Unit (Decl_Id) then
return True;
-- Inspect the declarations of a non-generic package body to
-- try and hide more entities from external visibility.
elsif Has_Referencer (Declarations (Decl),
In_Nested_Instance
or else
Is_Generic_Instance (Decl_Id),
Has_Referencer_Of_Non_Subprograms)
then
return True;
end if;
-- Subprogram body
elsif Nkind (Decl) = N_Subprogram_Body then
if Present (Corresponding_Spec (Decl)) then
Decl_Id := Corresponding_Spec (Decl);
-- A generic subprogram body acts as a referencer
if Is_Generic_Unit (Decl_Id) then
return True;
end if;
Ignore := Set_Referencer_Of_Non_Subprograms;
-- Otherwise this is a stand alone subprogram body
else
Decl_Id := Defining_Entity (Decl);
if not Set_Referencer_Of_Non_Subprograms
and then not Subprogram_Table.Get (Decl_Id)
then
-- We can reset Is_Public right away
Set_Is_Public (Decl_Id, False);
end if;
end if;
-- Freeze node
elsif Nkind (Decl) = N_Freeze_Entity then
declare
Discard : Boolean;
pragma Unreferenced (Discard);
begin
-- Inspect the actions to find references to subprograms.
-- We assume that the actions do not contain other kinds
-- of references and, therefore, we do not stop the scan
-- or set Has_Referencer_Of_Non_Subprograms here. Doing
-- it would pessimize common cases for which the actions
-- contain the declaration of an init procedure, since
-- such a procedure is automatically marked inline.
Discard :=
Has_Referencer (Actions (Decl),
In_Nested_Instance,
Has_Referencer_Of_Non_Subprograms);
end;
-- Exceptions, objects and renamings do not need to be public
-- if they are not followed by a construct which can reference
-- and export them.
elsif Nkind (Decl) in N_Exception_Declaration
| N_Object_Declaration
| N_Object_Renaming_Declaration
then
Decl_Id := Defining_Entity (Decl);
-- We cannot say anything for objects declared in nested
-- instances because instantiations are not done yet so the
-- bodies are not visible and could contain references to
-- them.
if not In_Nested_Instance
and then not Is_Imported (Decl_Id)
and then not Is_Exported (Decl_Id)
and then No (Interface_Name (Decl_Id))
and then not Has_Referencer_Of_Non_Subprograms
then
Set_Is_Public (Decl_Id, False);
end if;
-- Likewise for subprograms and renamings, but we work harder
-- for them to see whether they are referenced on an individual
-- basis by looking into the table of referenced subprograms.
elsif Nkind (Decl) in N_Subprogram_Declaration
| N_Subprogram_Renaming_Declaration
then
Decl_Id := Defining_Entity (Decl);
-- We cannot say anything for subprograms declared in nested
-- instances because instantiations are not done yet so the
-- bodies are not visible and could contain references to
-- them, except if we still have no subprograms at all which
-- are referenced by an inlined body.
if (not In_Nested_Instance
or else not Subprogram_Table.Get_First)
and then not Is_Imported (Decl_Id)
and then not Is_Exported (Decl_Id)
and then No (Interface_Name (Decl_Id))
and then not Subprogram_Table.Get (Decl_Id)
then
Set_Is_Public (Decl_Id, False);
end if;
-- For a subprogram renaming, if the entity is referenced,
-- then so is the renamed subprogram. But there is an issue
-- with generic bodies because instantiations are not done
-- yet and, therefore, cannot be scanned for referencers.
-- That's why we use an approximation and test that we have
-- at least one subprogram referenced by an inlined body
-- instead of precisely the entity of this renaming.
if Nkind (Decl) = N_Subprogram_Renaming_Declaration
and then Subprogram_Table.Get_First
and then Is_Entity_Name (Name (Decl))
and then Present (Entity (Name (Decl)))
and then Is_Subprogram (Entity (Name (Decl)))
then
Subprogram_Table.Set (Entity (Name (Decl)), True);
end if;
end if;
Prev (Decl);
end loop;
return Has_Referencer_Of_Non_Subprograms;
end Has_Referencer;
-------------------------
-- Scan_Subprogram_Ref --
-------------------------
function Scan_Subprogram_Ref (N : Node_Id) return Traverse_Result is
begin
-- Detect a reference of the form
-- Subp_Call
if Nkind (N) in N_Subprogram_Call
and then Is_Entity_Name (Name (N))
and then Present (Entity (Name (N)))
and then Is_Subprogram (Entity (Name (N)))
then
Subprogram_Table.Set (Entity (Name (N)), True);
-- Detect a reference of the form
-- Subp'Some_Attribute
elsif Nkind (N) = N_Attribute_Reference
and then Is_Entity_Name (Prefix (N))
and then Present (Entity (Prefix (N)))
and then Is_Subprogram (Entity (Prefix (N)))
then
Subprogram_Table.Set (Entity (Prefix (N)), True);
-- Constants can be substituted by their value in gigi, which may
-- contain a reference, so scan the value recursively.
elsif Is_Entity_Name (N)
and then Present (Entity (N))
and then Ekind (Entity (N)) = E_Constant
then
declare
Val : constant Node_Id := Constant_Value (Entity (N));
begin
if Present (Val)
and then not Compile_Time_Known_Value (Val)
then
Scan_Subprogram_Refs (Val);
end if;
end;
end if;
return OK;
end Scan_Subprogram_Ref;
--------------------------
-- Scan_Subprogram_Refs --
--------------------------
procedure Scan_Subprogram_Refs (Node : Node_Id) is
begin
if not Traversed_Table.Get (Node) then
Traversed_Table.Set (Node, True);
Traverse_And_Scan_Subprogram_Refs (Node);
end if;
end Scan_Subprogram_Refs;
-- Local variables
Discard : Boolean;
pragma Unreferenced (Discard);
-- Start of processing for Hide_Public_Entities
begin
-- The algorithm examines the top level declarations of a package
-- body in reverse looking for a construct that may export entities
-- declared prior to it. If such a scenario is encountered, then all
-- entities in the range Last (Decls) .. construct are hidden from
-- external visibility. Consider:
-- package Pack is
-- generic
-- package Gen is
-- end Gen;
-- end Pack;
-- package body Pack is
-- External_Obj : ...; -- (1)
-- package body Gen is -- (2)
-- ... External_Obj ... -- (3)
-- end Gen;
-- Local_Obj : ...; -- (4)
-- end Pack;
-- In this example Local_Obj (4) must not be externally visible as
-- it cannot be exported by anything in Pack. The body of generic
-- package Gen (2) on the other hand acts as a "referencer" and may
-- export anything declared before it. Since the compiler does not
-- perform flow analysis, it is not possible to determine precisely
-- which entities will be exported when Gen is instantiated. In the
-- example above External_Obj (1) is exported at (3), but this may
-- not always be the case. The algorithm takes a conservative stance
-- and leaves entity External_Obj public.
-- This very conservative algorithm is supplemented by a more precise
-- processing for inlined bodies. For them, we traverse the syntactic
-- tree and record which subprograms are actually referenced from it.
-- This makes it possible to compute a much smaller set of externally
-- visible subprograms in the absence of generic bodies, which can
-- have a significant impact on the inlining decisions made in the
-- back end and the removal of out-of-line bodies from the object
-- code. We do it only for inlined bodies because they are supposed
-- to be reasonably small and tree traversal is very expensive.
-- Note that even this special processing is not optimal for inlined
-- bodies, because we treat all inlined subprograms alike. An optimal
-- algorithm would require computing the transitive closure of the
-- inlined subprograms that can really be referenced from other units
-- in the source code.
-- We could extend this processing for inlined bodies and record all
-- entities, not just subprograms, referenced from them, which would
-- make it possible to compute a much smaller set of all externally
-- visible entities in the absence of generic bodies. But this would
-- mean implementing a more thorough tree traversal of the bodies,
-- i.e. not just syntactic, and the gain would very likely be worth
-- neither the hassle nor the slowdown of the compiler.
-- Finally, an important thing to be aware of is that, at this point,
-- instantiations are not done yet so we cannot directly see inlined
-- bodies coming from them. That's not catastrophic because only the
-- actual parameters of the instantiations matter here, and they are
-- present in the declarations list of the instantiated packages.
Traversed_Table.Reset;
Subprogram_Table.Reset;
Discard := Has_Referencer (Decls, False, False);
end Hide_Public_Entities;
----------------------------------
-- Install_Composite_Operations --
----------------------------------
procedure Install_Composite_Operations (P : Entity_Id) is
Id : Entity_Id;
begin
Id := First_Entity (P);
while Present (Id) loop
if Is_Type (Id)
and then (Is_Limited_Composite (Id)
or else Is_Private_Composite (Id))
and then No (Private_Component (Id))
then
Set_Is_Limited_Composite (Id, False);
Set_Is_Private_Composite (Id, False);
end if;
Next_Entity (Id);
end loop;
end Install_Composite_Operations;
-- Local variables
Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
Saved_EA : constant Boolean := Expander_Active;
Saved_ISMP : constant Boolean :=
Ignore_SPARK_Mode_Pragmas_In_Instance;
-- Save the Ghost and SPARK mode-related data to restore on exit
Body_Id : Entity_Id;
HSS : Node_Id;
Last_Spec_Entity : Entity_Id;
New_N : Node_Id;
Pack_Decl : Node_Id;
Spec_Id : Entity_Id;
-- Start of processing for Analyze_Package_Body_Helper
begin
-- Find corresponding package specification, and establish the current
-- scope. The visible defining entity for the package is the defining
-- occurrence in the spec. On exit from the package body, all body
-- declarations are attached to the defining entity for the body, but
-- the later is never used for name resolution. In this fashion there
-- is only one visible entity that denotes the package.
-- Set Body_Id. Note that this will be reset to point to the generic
-- copy later on in the generic case.
Body_Id := Defining_Entity (N);
-- Body is body of package instantiation. Corresponding spec has already
-- been set.
if Present (Corresponding_Spec (N)) then
Spec_Id := Corresponding_Spec (N);
Pack_Decl := Unit_Declaration_Node (Spec_Id);
else
Spec_Id := Current_Entity_In_Scope (Defining_Entity (N));
if Present (Spec_Id)
and then Is_Package_Or_Generic_Package (Spec_Id)
then
Pack_Decl := Unit_Declaration_Node (Spec_Id);
if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then
Error_Msg_N ("cannot supply body for package renaming", N);
return;
elsif Present (Corresponding_Body (Pack_Decl)) then
Error_Msg_N ("redefinition of package body", N);
return;
end if;
else
Error_Msg_N ("missing specification for package body", N);
return;
end if;
if Is_Package_Or_Generic_Package (Spec_Id)
and then (Scope (Spec_Id) = Standard_Standard
or else Is_Child_Unit (Spec_Id))
and then not Unit_Requires_Body (Spec_Id)
then
if Ada_Version = Ada_83 then
Error_Msg_N
("optional package body (not allowed in Ada 95)??", N);
else
Error_Msg_N ("spec of this package does not allow a body", N);
Error_Msg_N ("\either remove the body or add pragma "
& "Elaborate_Body in the spec", N);
end if;
end if;
end if;
-- A [generic] package body freezes the contract of the nearest
-- enclosing package body and all other contracts encountered in
-- the same declarative part up to and excluding the package body:
-- package body Nearest_Enclosing_Package
-- with Refined_State => (State => Constit)
-- is
-- Constit : ...;
-- package body Freezes_Enclosing_Package_Body
-- with Refined_State => (State_2 => Constit_2)
-- is
-- Constit_2 : ...;
-- procedure Proc
-- with Refined_Depends => (Input => (Constit, Constit_2)) ...
-- This ensures that any annotations referenced by the contract of a
-- [generic] subprogram body declared within the current package body
-- are available. This form of freezing is decoupled from the usual
-- Freeze_xxx mechanism because it must also work in the context of
-- generics where normal freezing is disabled.
-- Only bodies coming from source should cause this type of freezing.
-- Instantiated generic bodies are excluded because their processing is
-- performed in a separate compilation pass which lacks enough semantic
-- information with respect to contract analysis. It is safe to suppress
-- the freezing of contracts in this case because this action already
-- took place at the end of the enclosing declarative part.
if Comes_From_Source (N)
and then not Is_Generic_Instance (Spec_Id)
then
Freeze_Previous_Contracts (N);
end if;
-- A package body is Ghost when the corresponding spec is Ghost. Set
-- the mode now to ensure that any nodes generated during analysis and
-- expansion are properly flagged as ignored Ghost.
Mark_And_Set_Ghost_Body (N, Spec_Id);
-- Deactivate expansion inside the body of ignored Ghost entities,
-- as this code will ultimately be ignored. This avoids requiring the
-- presence of run-time units which are not needed. Only do this for
-- user entities, as internally generated entities might still need
-- to be expanded (e.g. those generated for types).
if Present (Ignored_Ghost_Region)
and then Comes_From_Source (Body_Id)
then
Expander_Active := False;
end if;
-- If the body completes the initial declaration of a compilation unit
-- which is subject to pragma Elaboration_Checks, set the model of the
-- pragma because it applies to all parts of the unit.
Install_Elaboration_Model (Spec_Id);
Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
Style.Check_Identifier (Body_Id, Spec_Id);
if Is_Child_Unit (Spec_Id) then
if Nkind (Parent (N)) /= N_Compilation_Unit then
Error_Msg_NE
("body of child unit& cannot be an inner package", N, Spec_Id);
end if;
Set_Is_Child_Unit (Body_Id);
end if;
-- Generic package case
if Ekind (Spec_Id) = E_Generic_Package then
-- Disable expansion and perform semantic analysis on copy. The
-- unannotated body will be used in all instantiations.
Body_Id := Defining_Entity (N);
Mutate_Ekind (Body_Id, E_Package_Body);
Set_Scope (Body_Id, Scope (Spec_Id));
Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
Set_Body_Entity (Spec_Id, Body_Id);
Set_Spec_Entity (Body_Id, Spec_Id);
New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
Rewrite (N, New_N);
-- Once the contents of the generic copy and the template are
-- swapped, do the same for their respective aspect specifications.
Exchange_Aspects (N, New_N);
-- Collect all contract-related source pragmas found within the
-- template and attach them to the contract of the package body.
-- This contract is used in the capture of global references within
-- annotations.
Create_Generic_Contract (N);
-- Update Body_Id to point to the copied node for the remainder of
-- the processing.
Body_Id := Defining_Entity (N);
Start_Generic;
end if;
-- The Body_Id is that of the copied node in the generic case, the
-- current node otherwise. Note that N was rewritten above, so we must
-- be sure to get the latest Body_Id value.
Mutate_Ekind (Body_Id, E_Package_Body);
Set_Body_Entity (Spec_Id, Body_Id);
Set_Spec_Entity (Body_Id, Spec_Id);
-- Defining name for the package body is not a visible entity: Only the
-- defining name for the declaration is visible.
Set_Etype (Body_Id, Standard_Void_Type);
Set_Scope (Body_Id, Scope (Spec_Id));
Set_Corresponding_Spec (N, Spec_Id);
Set_Corresponding_Body (Pack_Decl, Body_Id);
-- The body entity is not used for semantics or code generation, but
-- it is attached to the entity list of the enclosing scope to simplify
-- the listing of back-annotations for the types it main contain.
if Scope (Spec_Id) /= Standard_Standard then
Append_Entity (Body_Id, Scope (Spec_Id));
end if;
-- Indicate that we are currently compiling the body of the package
Set_In_Package_Body (Spec_Id);
Set_Has_Completion (Spec_Id);
Last_Spec_Entity := Last_Entity (Spec_Id);
if Has_Aspects (N) then
Analyze_Aspect_Specifications (N, Body_Id);
end if;
Push_Scope (Spec_Id);
-- Set SPARK_Mode only for non-generic package
if Ekind (Spec_Id) = E_Package then
Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
Set_SPARK_Aux_Pragma (Body_Id, SPARK_Mode_Pragma);
Set_SPARK_Pragma_Inherited (Body_Id);
Set_SPARK_Aux_Pragma_Inherited (Body_Id);
-- A package body may be instantiated or inlined at a later pass.
-- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when
-- it applied to the package spec.
if Ignore_SPARK_Mode_Pragmas (Spec_Id) then
Ignore_SPARK_Mode_Pragmas_In_Instance := True;
end if;
end if;
Set_Categorization_From_Pragmas (N);
Install_Visible_Declarations (Spec_Id);
Install_Private_Declarations (Spec_Id);
Install_Private_With_Clauses (Spec_Id);
Install_Composite_Operations (Spec_Id);
Check_Anonymous_Access_Types (Spec_Id, N);
if Ekind (Spec_Id) = E_Generic_Package then
Set_Use (Generic_Formal_Declarations (Pack_Decl));
end if;
Set_Use (Visible_Declarations (Specification (Pack_Decl)));
Set_Use (Private_Declarations (Specification (Pack_Decl)));
-- This is a nested package, so it may be necessary to declare certain
-- inherited subprograms that are not yet visible because the parent
-- type's subprograms are now visible.
-- Note that for child units these operations were generated when
-- analyzing the package specification.
if Ekind (Scope (Spec_Id)) = E_Package
and then Scope (Spec_Id) /= Standard_Standard
and then not Is_Child_Unit (Spec_Id)
then
Declare_Inherited_Private_Subprograms (Spec_Id);
end if;
if Present (Declarations (N)) then
Analyze_Declarations (Declarations (N));
Inspect_Deferred_Constant_Completion (Declarations (N));
end if;
-- Verify that the SPARK_Mode of the body agrees with that of its spec
if Present (SPARK_Pragma (Body_Id)) then
if Present (SPARK_Aux_Pragma (Spec_Id)) then
if Get_SPARK_Mode_From_Annotation (SPARK_Aux_Pragma (Spec_Id)) =
Off
and then
Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
then
Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
Error_Msg_N ("incorrect application of SPARK_Mode#", N);
Error_Msg_Sloc := Sloc (SPARK_Aux_Pragma (Spec_Id));
Error_Msg_NE
("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
end if;
-- SPARK_Mode Off could complete no SPARK_Mode in a generic, either
-- as specified in source code, or because SPARK_Mode On is ignored
-- in an instance where the context is SPARK_Mode Off/Auto.
elsif Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = Off
and then (Is_Generic_Unit (Spec_Id) or else In_Instance)
then
null;
else
Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
Error_Msg_N ("incorrect application of SPARK_Mode#", N);
Error_Msg_Sloc := Sloc (Spec_Id);
Error_Msg_NE
("\no value was set for SPARK_Mode on & #", N, Spec_Id);
end if;
end if;
-- Analyze_Declarations has caused freezing of all types. Now generate
-- bodies for RACW primitives and stream attributes, if any.
if Ekind (Spec_Id) = E_Package and then Has_RACW (Spec_Id) then
-- Attach subprogram bodies to support RACWs declared in spec
Append_RACW_Bodies (Declarations (N), Spec_Id);
Analyze_List (Declarations (N));
end if;
HSS := Handled_Statement_Sequence (N);
if Present (HSS) then
Process_End_Label (HSS, 't', Spec_Id);
Analyze (HSS);
-- Check that elaboration code in a preelaborable package body is
-- empty other than null statements and labels (RM 10.2.1(6)).
Validate_Null_Statement_Sequence (N);
end if;
Validate_Categorization_Dependency (N, Spec_Id);
Check_Completion (Body_Id);
-- Generate start of body reference. Note that we do this fairly late,
-- because the call will use In_Extended_Main_Source_Unit as a check,
-- and we want to make sure that Corresponding_Stub links are set
Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
-- For a generic package, collect global references and mark them on
-- the original body so that they are not resolved again at the point
-- of instantiation.
if Ekind (Spec_Id) /= E_Package then
Save_Global_References (Original_Node (N));
End_Generic;
end if;
-- The entities of the package body have so far been chained onto the
-- declaration chain for the spec. That's been fine while we were in the
-- body, since we wanted them to be visible, but now that we are leaving
-- the package body, they are no longer visible, so we remove them from
-- the entity chain of the package spec entity, and copy them to the
-- entity chain of the package body entity, where they will never again
-- be visible.
if Present (Last_Spec_Entity) then
Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));
Set_Next_Entity (Last_Spec_Entity, Empty);
Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
Set_Last_Entity (Spec_Id, Last_Spec_Entity);
else
Set_First_Entity (Body_Id, First_Entity (Spec_Id));
Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
Set_First_Entity (Spec_Id, Empty);
Set_Last_Entity (Spec_Id, Empty);
end if;
Update_Use_Clause_Chain;
End_Package_Scope (Spec_Id);
-- All entities declared in body are not visible
declare
E : Entity_Id;
begin
E := First_Entity (Body_Id);
while Present (E) loop
Set_Is_Immediately_Visible (E, False);
Set_Is_Potentially_Use_Visible (E, False);
Set_Is_Hidden (E);
-- Child units may appear on the entity list (e.g. if they appear
-- in the context of a subunit) but they are not body entities.
if not Is_Child_Unit (E) then
Set_Is_Package_Body_Entity (E);
end if;
Next_Entity (E);
end loop;
end;
Check_References (Body_Id);
-- For a generic unit, check that the formal parameters are referenced,
-- and that local variables are used, as for regular packages.
if Ekind (Spec_Id) = E_Generic_Package then
Check_References (Spec_Id);
end if;
-- At this point all entities of the package body are externally visible
-- to the linker as their Is_Public flag is set to True. This proactive
-- approach is necessary because an inlined or a generic body for which
-- code is generated in other units may need to see these entities. Cut
-- down the number of global symbols that do not need public visibility
-- as this has two beneficial effects:
-- (1) It makes the compilation process more efficient.
-- (2) It gives the code generator more leeway to optimize within each
-- unit, especially subprograms.
-- This is done only for top-level library packages or child units as
-- the algorithm does a top-down traversal of the package body. This is
-- also done for instances because instantiations are still pending by
-- the time the enclosing package body is analyzed.
if (Scope (Spec_Id) = Standard_Standard
or else Is_Child_Unit (Spec_Id)
or else Is_Generic_Instance (Spec_Id))
and then not Is_Generic_Unit (Spec_Id)
then
Hide_Public_Entities (Declarations (N));
end if;
-- If expander is not active, then here is where we turn off the
-- In_Package_Body flag, otherwise it is turned off at the end of the
-- corresponding expansion routine. If this is an instance body, we need
-- to qualify names of local entities, because the body may have been
-- compiled as a preliminary to another instantiation.
if not Expander_Active then
Set_In_Package_Body (Spec_Id, False);
if Is_Generic_Instance (Spec_Id)
and then Operating_Mode = Generate_Code
then
Qualify_Entity_Names (N);
end if;
end if;
if Present (Ignored_Ghost_Region) then
Expander_Active := Saved_EA;
end if;
Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
Restore_Ghost_Region (Saved_GM, Saved_IGR);
end Analyze_Package_Body_Helper;
---------------------------------
-- Analyze_Package_Declaration --
---------------------------------
procedure Analyze_Package_Declaration (N : Node_Id) is
Id : constant Node_Id := Defining_Entity (N);
Is_Comp_Unit : constant Boolean :=
Nkind (Parent (N)) = N_Compilation_Unit;
Body_Required : Boolean;
-- True when this package declaration requires a corresponding body
begin
if Debug_Flag_C then
Write_Str ("==> package spec ");
Write_Name (Chars (Id));
Write_Str (" from ");
Write_Location (Sloc (N));
Write_Eol;
Indent;
end if;
Generate_Definition (Id);
Enter_Name (Id);
Mutate_Ekind (Id, E_Package);
Set_Etype (Id, Standard_Void_Type);
-- Set SPARK_Mode from context
Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
Set_SPARK_Aux_Pragma (Id, SPARK_Mode_Pragma);
Set_SPARK_Pragma_Inherited (Id);
Set_SPARK_Aux_Pragma_Inherited (Id);
-- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case
-- the body of this package is instantiated or inlined later and out of
-- context. The body uses this attribute to restore the value of the
-- global flag.
if Ignore_SPARK_Mode_Pragmas_In_Instance then
Set_Ignore_SPARK_Mode_Pragmas (Id);
end if;
-- Analyze aspect specifications immediately, since we need to recognize
-- things like Pure early enough to diagnose violations during analysis.
if Has_Aspects (N) then
Analyze_Aspect_Specifications (N, Id);
end if;
-- Ada 2005 (AI-217): Check if the package has been illegally named in
-- a limited-with clause of its own context. In this case the error has
-- been previously notified by Analyze_Context.
-- limited with Pkg; -- ERROR
-- package Pkg is ...
if From_Limited_With (Id) then
return;
end if;
Push_Scope (Id);
Set_Is_Pure (Id, Is_Pure (Enclosing_Lib_Unit_Entity));
Set_Categorization_From_Pragmas (N);
Analyze (Specification (N));
Validate_Categorization_Dependency (N, Id);
-- Determine whether the package requires a body. Abstract states are
-- intentionally ignored because they do require refinement which can
-- only come in a body, but at the same time they do not force the need
-- for a body on their own (SPARK RM 7.1.4(4) and 7.2.2(3)).
Body_Required := Unit_Requires_Body (Id);
if not Body_Required then
-- If the package spec does not require an explicit body, then there
-- are not entities requiring completion in the language sense. Call
-- Check_Completion now to ensure that nested package declarations
-- that require an implicit body get one. (In the case where a body
-- is required, Check_Completion is called at the end of the body's
-- declarative part.)
Check_Completion;
-- If the package spec does not require an explicit body, then all
-- abstract states declared in nested packages cannot possibly get
-- a proper refinement (SPARK RM 7.2.2(3)). This check is performed
-- only when the compilation unit is the main unit to allow for
-- modular SPARK analysis where packages do not necessarily have
-- bodies.
if Is_Comp_Unit then
Check_State_Refinements
(Context => N,
Is_Main_Unit => Parent (N) = Cunit (Main_Unit));
end if;
-- Warn about references to unset objects, which is straightforward
-- for packages with no bodies. For packages with bodies this is more
-- complicated, because some of the objects might be set between spec
-- and body elaboration, in nested or child packages, etc.
Check_References (Id);
end if;
-- Set Body_Required indication on the compilation unit node
if Is_Comp_Unit then
Set_Body_Required (Parent (N), Body_Required);
if Legacy_Elaboration_Checks and not Body_Required then
Set_Suppress_Elaboration_Warnings (Id);
end if;
end if;
End_Package_Scope (Id);
-- For the declaration of a library unit that is a remote types package,
-- check legality rules regarding availability of stream attributes for
-- types that contain non-remote access values. This subprogram performs
-- visibility tests that rely on the fact that we have exited the scope
-- of Id.
if Is_Comp_Unit then
Validate_RT_RAT_Component (N);
end if;
if Debug_Flag_C then
Outdent;
Write_Str ("<== package spec ");
Write_Name (Chars (Id));
Write_Str (" from ");
Write_Location (Sloc (N));
Write_Eol;
end if;
end Analyze_Package_Declaration;
-----------------------------------
-- Analyze_Package_Specification --
-----------------------------------
-- Note that this code is shared for the analysis of generic package specs
-- (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
procedure Analyze_Package_Specification (N : Node_Id) is
Id : constant Entity_Id := Defining_Entity (N);
Orig_Decl : constant Node_Id := Original_Node (Parent (N));
Vis_Decls : constant List_Id := Visible_Declarations (N);
Priv_Decls : constant List_Id := Private_Declarations (N);
E : Entity_Id;
L : Entity_Id;
Public_Child : Boolean;
Private_With_Clauses_Installed : Boolean := False;
-- In Ada 2005, private with_clauses are visible in the private part
-- of a nested package, even if it appears in the public part of the
-- enclosing package. This requires a separate step to install these
-- private_with_clauses, and remove them at the end of the nested
-- package.
procedure Clear_Constants (Id : Entity_Id);
-- Clears constant indications (Never_Set_In_Source, Constant_Value,
-- and Is_True_Constant) on all variables that are entities of Id.
-- A recursive call is made for all packages and generic packages.
procedure Generate_Parent_References;
-- For a child unit, generate references to parent units, for
-- GNAT Studio navigation purposes.
function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;
-- Child and Unit are entities of compilation units. True if Child
-- is a public child of Parent as defined in 10.1.1
procedure Inspect_Unchecked_Union_Completion (Decls : List_Id);
-- Reject completion of an incomplete or private type declarations
-- having a known discriminant part by an unchecked union.
procedure Inspect_Untagged_Record_Completion (Decls : List_Id);
-- Find out whether a nonlimited untagged record completion has got a
-- primitive equality operator and, if so, make it so that it will be
-- used as the predefined operator of the private view of the record.
procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id);
-- Given the package entity of a generic package instantiation or
-- formal package whose corresponding generic is a child unit, installs
-- the private declarations of each of the child unit's parents.
-- This has to be done at the point of entering the instance package's
-- private part rather than being done in Sem_Ch12.Install_Parent
-- (which is where the parents' visible declarations are installed).
---------------------
-- Clear_Constants --
---------------------
procedure Clear_Constants (Id : Entity_Id) is
E : Entity_Id;
begin
-- Ignore package renamings, not interesting and they can cause self
-- referential loops in the code below.
if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then
return;
end if;
-- Note: in the loop below, the check for Next_Entity pointing back
-- to the package entity may seem odd, but it is needed, because a
-- package can contain a renaming declaration to itself, and such
-- renamings are generated automatically within package instances.
E := First_Entity (Id);
while Present (E) and then E /= Id loop
if Ekind (E) = E_Variable then
Set_Never_Set_In_Source (E, False);
Set_Is_True_Constant (E, False);
Set_Current_Value (E, Empty);
Set_Is_Known_Null (E, False);
Set_Last_Assignment (E, Empty);
if not Can_Never_Be_Null (E) then
Set_Is_Known_Non_Null (E, False);
end if;
elsif Is_Package_Or_Generic_Package (E) then
Clear_Constants (E);
end if;
Next_Entity (E);
end loop;
end Clear_Constants;
--------------------------------
-- Generate_Parent_References --
--------------------------------
procedure Generate_Parent_References is
Decl : constant Node_Id := Parent (N);
begin
if Id = Cunit_Entity (Main_Unit)
or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))
then
Generate_Reference (Id, Scope (Id), 'k', False);
elsif Nkind (Unit (Cunit (Main_Unit))) not in
N_Subprogram_Body | N_Subunit
then
-- If current unit is an ancestor of main unit, generate a
-- reference to its own parent.
declare
U : Node_Id;
Main_Spec : Node_Id := Unit (Cunit (Main_Unit));
begin
if Nkind (Main_Spec) = N_Package_Body then
Main_Spec := Unit (Library_Unit (Cunit (Main_Unit)));
end if;
U := Parent_Spec (Main_Spec);
while Present (U) loop
if U = Parent (Decl) then
Generate_Reference (Id, Scope (Id), 'k', False);
exit;
elsif Nkind (Unit (U)) = N_Package_Body then
exit;
else
U := Parent_Spec (Unit (U));
end if;
end loop;
end;
end if;
end Generate_Parent_References;
---------------------
-- Is_Public_Child --
---------------------
function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is
begin
if not Is_Private_Descendant (Child) then
return True;
else
if Child = Unit then
return not Private_Present (
Parent (Unit_Declaration_Node (Child)));
else
return Is_Public_Child (Scope (Child), Unit);
end if;
end if;
end Is_Public_Child;
----------------------------------------
-- Inspect_Unchecked_Union_Completion --
----------------------------------------
procedure Inspect_Unchecked_Union_Completion (Decls : List_Id) is
Decl : Node_Id;
begin
Decl := First (Decls);
while Present (Decl) loop
-- We are looking for an incomplete or private type declaration
-- with a known_discriminant_part whose full view is an
-- Unchecked_Union. The seemingly useless check with Is_Type
-- prevents cascaded errors when routines defined only for type
-- entities are called with non-type entities.
if Nkind (Decl) in N_Incomplete_Type_Declaration
| N_Private_Type_Declaration
and then Is_Type (Defining_Identifier (Decl))
and then Has_Discriminants (Defining_Identifier (Decl))
and then Present (Full_View (Defining_Identifier (Decl)))
and then
Is_Unchecked_Union (Full_View (Defining_Identifier (Decl)))
then
Error_Msg_N
("completion of discriminated partial view "
& "cannot be an unchecked union",
Full_View (Defining_Identifier (Decl)));
end if;
Next (Decl);
end loop;
end Inspect_Unchecked_Union_Completion;
----------------------------------------
-- Inspect_Untagged_Record_Completion --
----------------------------------------
procedure Inspect_Untagged_Record_Completion (Decls : List_Id) is
Decl : Node_Id;
begin
Decl := First (Decls);
while Present (Decl) loop
-- We are looking for a full type declaration of an untagged
-- record with a private declaration and primitive operations.
if Nkind (Decl) in N_Full_Type_Declaration
and then Is_Record_Type (Defining_Identifier (Decl))
and then not Is_Limited_Type (Defining_Identifier (Decl))
and then not Is_Tagged_Type (Defining_Identifier (Decl))
and then Has_Private_Declaration (Defining_Identifier (Decl))
and then Has_Primitive_Operations (Defining_Identifier (Decl))
then
declare
Prim_List : constant Elist_Id :=
Collect_Primitive_Operations (Defining_Identifier (Decl));
E : Entity_Id;
Ne_Id : Entity_Id;
Op_Decl : Node_Id;
Op_Id : Entity_Id;
Prim : Elmt_Id;
begin
Prim := First_Elmt (Prim_List);
while Present (Prim) loop
Op_Id := Node (Prim);
Op_Decl := Declaration_Node (Op_Id);
if Nkind (Op_Decl) in N_Subprogram_Specification then
Op_Decl := Parent (Op_Decl);
end if;
-- We are looking for an equality operator immediately
-- visible and declared in the private part followed by
-- the synthesized inequality operator.
if Is_User_Defined_Equality (Op_Id)
and then Is_Immediately_Visible (Op_Id)
and then List_Containing (Op_Decl) = Decls
then
Ne_Id := Next_Entity (Op_Id);
pragma Assert (Ekind (Ne_Id) = E_Function
and then Corresponding_Equality (Ne_Id) = Op_Id);
E := First_Private_Entity (Id);
-- Move them from the private part of the entity list
-- up to the end of the visible part of the same list.
Remove_Entity (Op_Id);
Remove_Entity (Ne_Id);
Link_Entities (Prev_Entity (E), Op_Id);
Link_Entities (Op_Id, Ne_Id);
Link_Entities (Ne_Id, E);
-- And if the private part contains another equality
-- operator, move the equality operator to after it
-- in the homonym chain, so that all its next homonyms
-- in the same scope, if any, also are in the visible
-- part. This is relied upon to resolve expanded names
-- in Collect_Interps for example.
while Present (E) loop
exit when Ekind (E) = E_Function
and then Chars (E) = Name_Op_Eq;
Next_Entity (E);
end loop;
if Present (E) then
Remove_Homonym (Op_Id);
Set_Homonym (Op_Id, Homonym (E));
Set_Homonym (E, Op_Id);
end if;
exit;
end if;
Next_Elmt (Prim);
end loop;
end;
end if;
Next (Decl);
end loop;
end Inspect_Untagged_Record_Completion;
-----------------------------------------
-- Install_Parent_Private_Declarations --
-----------------------------------------
procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id) is
Inst_Par : Entity_Id;
Gen_Par : Entity_Id;
Inst_Node : Node_Id;
begin
Inst_Par := Inst_Id;
Gen_Par :=
Generic_Parent (Specification (Unit_Declaration_Node (Inst_Par)));
while Present (Gen_Par) and then Is_Child_Unit (Gen_Par) loop
Inst_Node := Get_Unit_Instantiation_Node (Inst_Par);
if Nkind (Inst_Node) in
N_Package_Instantiation | N_Formal_Package_Declaration
and then Nkind (Name (Inst_Node)) = N_Expanded_Name
then
Inst_Par := Entity (Prefix (Name (Inst_Node)));
if Present (Renamed_Entity (Inst_Par)) then
Inst_Par := Renamed_Entity (Inst_Par);
end if;
-- The instance may appear in a sibling generic unit, in
-- which case the prefix must include the common (generic)
-- ancestor, which is treated as a current instance.
if Inside_A_Generic
and then Ekind (Inst_Par) = E_Generic_Package
then
Gen_Par := Inst_Par;
pragma Assert (In_Open_Scopes (Gen_Par));
else
Gen_Par :=
Generic_Parent
(Specification (Unit_Declaration_Node (Inst_Par)));
end if;
-- Install the private declarations and private use clauses
-- of a parent instance of the child instance, unless the
-- parent instance private declarations have already been
-- installed earlier in Analyze_Package_Specification, which
-- happens when a generic child is instantiated, and the
-- instance is a child of the parent instance.
-- Installing the use clauses of the parent instance twice
-- is both unnecessary and wrong, because it would cause the
-- clauses to be chained to themselves in the use clauses
-- list of the scope stack entry. That in turn would cause
-- an endless loop from End_Use_Clauses upon scope exit.
-- The parent is now fully visible. It may be a hidden open
-- scope if we are currently compiling some child instance
-- declared within it, but while the current instance is being
-- compiled the parent is immediately visible. In particular
-- its entities must remain visible if a stack save/restore
-- takes place through a call to Rtsfind.
if Present (Gen_Par) then
if not In_Private_Part (Inst_Par) then
Install_Private_Declarations (Inst_Par);
Set_Use (Private_Declarations
(Specification
(Unit_Declaration_Node (Inst_Par))));
Set_Is_Hidden_Open_Scope (Inst_Par, False);
end if;
-- If we've reached the end of the generic instance parents,
-- then finish off by looping through the nongeneric parents
-- and installing their private declarations.
-- If one of the non-generic parents is itself on the scope
-- stack, do not install its private declarations: they are
-- installed in due time when the private part of that parent
-- is analyzed.
else
while Present (Inst_Par)
and then Inst_Par /= Standard_Standard
and then (not In_Open_Scopes (Inst_Par)
or else not In_Private_Part (Inst_Par))
loop
if Nkind (Inst_Node) = N_Formal_Package_Declaration
or else
not Is_Ancestor_Package
(Inst_Par, Cunit_Entity (Current_Sem_Unit))
then
Install_Private_Declarations (Inst_Par);
Set_Use
(Private_Declarations
(Specification
(Unit_Declaration_Node (Inst_Par))));
Inst_Par := Scope (Inst_Par);
else
exit;
end if;
end loop;
exit;
end if;
else
exit;
end if;
end loop;
end Install_Parent_Private_Declarations;
-- Start of processing for Analyze_Package_Specification
begin
if Present (Vis_Decls) then
Analyze_Declarations (Vis_Decls);
end if;
-- Inspect the entities defined in the package and ensure that all
-- incomplete types have received full declarations. Build default
-- initial condition and invariant procedures for all qualifying types.
E := First_Entity (Id);
while Present (E) loop
-- Check on incomplete types
-- AI05-0213: A formal incomplete type has no completion, and neither
-- does the corresponding subtype in an instance.
if Is_Incomplete_Type (E)
and then No (Full_View (E))
and then not Is_Generic_Type (E)
and then not From_Limited_With (E)
and then not Is_Generic_Actual_Type (E)
then
Error_Msg_N ("no declaration in visible part for incomplete}", E);
end if;
Next_Entity (E);
end loop;
if Is_Remote_Call_Interface (Id)
and then Nkind (Parent (Parent (N))) = N_Compilation_Unit
then
Validate_RCI_Declarations (Id);
end if;
-- Save global references in the visible declarations, before installing
-- private declarations of parent unit if there is one, because the
-- privacy status of types defined in the parent will change. This is
-- only relevant for generic child units, but is done in all cases for
-- uniformity.
if Ekind (Id) = E_Generic_Package
and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
then
declare
Orig_Spec : constant Node_Id := Specification (Orig_Decl);
Save_Priv : constant List_Id := Private_Declarations (Orig_Spec);
begin
-- Insert the freezing nodes after the visible declarations to
-- ensure that we analyze its aspects; needed to ensure that
-- global entities referenced in the aspects are properly handled.
if Ada_Version >= Ada_2012
and then Is_Non_Empty_List (Vis_Decls)
and then Is_Empty_List (Priv_Decls)
then
Insert_List_After_And_Analyze
(Last (Vis_Decls), Freeze_Entity (Id, Last (Vis_Decls)));
end if;
Set_Private_Declarations (Orig_Spec, Empty_List);
Save_Global_References (Orig_Decl);
Set_Private_Declarations (Orig_Spec, Save_Priv);
end;
end if;
-- If package is a public child unit, then make the private declarations
-- of the parent visible.
Public_Child := False;
declare
Par : Entity_Id;
Pack_Decl : Node_Id;
Par_Spec : Node_Id;
begin
Par := Id;
Par_Spec := Parent_Spec (Parent (N));
-- If the package is formal package of an enclosing generic, it is
-- transformed into a local generic declaration, and compiled to make
-- its spec available. We need to retrieve the original generic to
-- determine whether it is a child unit, and install its parents.
if No (Par_Spec)
and then
Nkind (Original_Node (Parent (N))) = N_Formal_Package_Declaration
then
Par := Entity (Name (Original_Node (Parent (N))));
Par_Spec := Parent_Spec (Unit_Declaration_Node (Par));
end if;
if Present (Par_Spec) then
Generate_Parent_References;
while Scope (Par) /= Standard_Standard
and then Is_Public_Child (Id, Par)
and then In_Open_Scopes (Par)
loop
Public_Child := True;
Par := Scope (Par);
Install_Private_Declarations (Par);
Install_Private_With_Clauses (Par);
Pack_Decl := Unit_Declaration_Node (Par);
Set_Use (Private_Declarations (Specification (Pack_Decl)));
end loop;
end if;
end;
if Is_Compilation_Unit (Id) then
Install_Private_With_Clauses (Id);
else
-- The current compilation unit may include private with_clauses,
-- which are visible in the private part of the current nested
-- package, and have to be installed now. This is not done for
-- nested instantiations, where the private with_clauses of the
-- enclosing unit have no effect once the instantiation info is
-- established and we start analyzing the package declaration.
declare
Comp_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit);
begin
if Is_Package_Or_Generic_Package (Comp_Unit)
and then not In_Private_Part (Comp_Unit)
and then not In_Instance
then
Install_Private_With_Clauses (Comp_Unit);
Private_With_Clauses_Installed := True;
end if;
end;
end if;
-- If this is a package associated with a generic instance or formal
-- package, then the private declarations of each of the generic's
-- parents must be installed at this point, but not if this is the
-- abbreviated instance created to check a formal package, see the
-- same condition in Analyze_Package_Instantiation.
if Is_Generic_Instance (Id)
and then not Is_Abbreviated_Instance (Id)
then
Install_Parent_Private_Declarations (Id);
end if;
-- Analyze private part if present. The flag In_Private_Part is reset
-- in Uninstall_Declarations.
L := Last_Entity (Id);
if Present (Priv_Decls) then
Set_In_Private_Part (Id);
-- Upon entering a public child's private part, it may be necessary
-- to declare subprograms that were derived in the package's visible
-- part but not yet made visible.
if Public_Child then
Declare_Inherited_Private_Subprograms (Id);
end if;
Analyze_Declarations (Priv_Decls);
-- Check the private declarations for incomplete deferred constants
Inspect_Deferred_Constant_Completion (Priv_Decls);
-- The first private entity is the immediate follower of the last
-- visible entity, if there was one.
if Present (L) then
Set_First_Private_Entity (Id, Next_Entity (L));
else
Set_First_Private_Entity (Id, First_Entity (Id));
end if;
-- There may be inherited private subprograms that need to be declared,
-- even in the absence of an explicit private part. If there are any
-- public declarations in the package and the package is a public child
-- unit, then an implicit private part is assumed.
elsif Present (L) and then Public_Child then
Set_In_Private_Part (Id);
Declare_Inherited_Private_Subprograms (Id);
Set_First_Private_Entity (Id, Next_Entity (L));
end if;
E := First_Entity (Id);
while Present (E) loop
-- Check rule of 3.6(11), which in general requires waiting till all
-- full types have been seen.
if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then
Check_Aliased_Component_Types (E);
end if;
-- Check preelaborable initialization for full type completing a
-- private type when aspect Preelaborable_Initialization is True
-- or is specified by Preelaborable_Initialization attributes
-- (in the case of a private type in a generic unit). We pass
-- the expression of the aspect (when present) to the parameter
-- Preelab_Init_Expr to take into account the rule that presumes
-- that subcomponents of generic formal types mentioned in the
-- type's P_I aspect have preelaborable initialization (see
-- AI12-0409 and RM 10.2.1(11.8/5)).
if Is_Type (E) and then Must_Have_Preelab_Init (E) then
declare
PI_Aspect : constant Node_Id :=
Find_Aspect
(E, Aspect_Preelaborable_Initialization);
PI_Expr : Node_Id := Empty;
begin
if Present (PI_Aspect) then
PI_Expr := Expression (PI_Aspect);
end if;
if not Has_Preelaborable_Initialization
(E, Preelab_Init_Expr => PI_Expr)
then
Error_Msg_N
("full view of & does not have "
& "preelaborable initialization", E);
end if;
end;
end if;
Next_Entity (E);
end loop;
-- Ada 2005 (AI-216): The completion of an incomplete or private type
-- declaration having a known_discriminant_part shall not be an
-- unchecked union type.
if Present (Vis_Decls) then
Inspect_Unchecked_Union_Completion (Vis_Decls);
end if;
if Present (Priv_Decls) then
Inspect_Unchecked_Union_Completion (Priv_Decls);
end if;
-- Implement AI12-0101 (which only removes a legality rule) and then
-- AI05-0123 (which directly applies in the previously illegal case)
-- in Ada 2012. Note that AI12-0101 is a binding interpretation.
if Present (Priv_Decls) and then Ada_Version >= Ada_2012 then
Inspect_Untagged_Record_Completion (Priv_Decls);
end if;
if Ekind (Id) = E_Generic_Package
and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
and then Present (Priv_Decls)
then
-- Save global references in private declarations, ignoring the
-- visible declarations that were processed earlier.
declare
Orig_Spec : constant Node_Id := Specification (Orig_Decl);
Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec);
Save_Form : constant List_Id :=
Generic_Formal_Declarations (Orig_Decl);
begin
-- Insert the freezing nodes after the private declarations to
-- ensure that we analyze its aspects; needed to ensure that
-- global entities referenced in the aspects are properly handled.
if Ada_Version >= Ada_2012
and then Is_Non_Empty_List (Priv_Decls)
then
Insert_List_After_And_Analyze
(Last (Priv_Decls), Freeze_Entity (Id, Last (Priv_Decls)));
end if;
Set_Visible_Declarations (Orig_Spec, Empty_List);
Set_Generic_Formal_Declarations (Orig_Decl, Empty_List);
Save_Global_References (Orig_Decl);
Set_Generic_Formal_Declarations (Orig_Decl, Save_Form);
Set_Visible_Declarations (Orig_Spec, Save_Vis);
end;
end if;
Process_End_Label (N, 'e', Id);
-- Remove private_with_clauses of enclosing compilation unit, if they
-- were installed.
if Private_With_Clauses_Installed then
Remove_Private_With_Clauses (Cunit (Current_Sem_Unit));
end if;
-- For the case of a library level package, we must go through all the
-- entities clearing the indications that the value may be constant and
-- not modified. Why? Because any client of this package may modify
-- these values freely from anywhere. This also applies to any nested
-- packages or generic packages.
-- For now we unconditionally clear constants for packages that are
-- instances of generic packages. The reason is that we do not have the
-- body yet, and we otherwise think things are unreferenced when they
-- are not. This should be fixed sometime (the effect is not terrible,
-- we just lose some warnings, and also some cases of value propagation)
-- ???
if Is_Library_Level_Entity (Id)
or else Is_Generic_Instance (Id)
then
Clear_Constants (Id);
end if;
-- Output relevant information as to why the package requires a body.
-- Do not consider generated packages as this exposes internal symbols
-- and leads to confusing messages.
if List_Body_Required_Info
and then In_Extended_Main_Source_Unit (Id)
and then Unit_Requires_Body (Id)
and then Comes_From_Source (Id)
then
Unit_Requires_Body_Info (Id);
end if;
-- Nested package specs that do not require bodies are not checked for
-- ineffective use clauses due to the possibility of subunits. This is
-- because at this stage it is impossible to tell whether there will be
-- a separate body.
if not Unit_Requires_Body (Id)
and then Is_Compilation_Unit (Id)
and then not Is_Private_Descendant (Id)
then
Update_Use_Clause_Chain;
end if;
end Analyze_Package_Specification;
--------------------------------------
-- Analyze_Private_Type_Declaration --
--------------------------------------
procedure Analyze_Private_Type_Declaration (N : Node_Id) is
Id : constant Entity_Id := Defining_Identifier (N);
PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity);
begin
Generate_Definition (Id);
Set_Is_Pure (Id, PF);
Reinit_Size_Align (Id);
if not Is_Package_Or_Generic_Package (Current_Scope)
or else In_Private_Part (Current_Scope)
then
Error_Msg_N ("invalid context for private declaration", N);
end if;
New_Private_Type (N, Id, N);
Set_Depends_On_Private (Id);
-- Set the SPARK mode from the current context
Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
Set_SPARK_Pragma_Inherited (Id);
if Has_Aspects (N) then
Analyze_Aspect_Specifications (N, Id);
end if;
end Analyze_Private_Type_Declaration;
----------------------------------
-- Check_Anonymous_Access_Types --
----------------------------------
procedure Check_Anonymous_Access_Types
(Spec_Id : Entity_Id;
P_Body : Node_Id)
is
E : Entity_Id;
IR : Node_Id;
begin
-- Itype references are only needed by gigi, to force elaboration of
-- itypes. In the absence of code generation, they are not needed.
if not Expander_Active then
return;
end if;
E := First_Entity (Spec_Id);
while Present (E) loop
if Ekind (E) = E_Anonymous_Access_Type
and then From_Limited_With (E)
then
IR := Make_Itype_Reference (Sloc (P_Body));
Set_Itype (IR, E);
if No (Declarations (P_Body)) then
Set_Declarations (P_Body, New_List (IR));
else
Prepend (IR, Declarations (P_Body));
end if;
end if;
Next_Entity (E);
end loop;
end Check_Anonymous_Access_Types;
-------------------------------------------
-- Declare_Inherited_Private_Subprograms --
-------------------------------------------
procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is
function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean;
-- Check whether an inherited subprogram S is an operation of an
-- untagged derived type T.
---------------------
-- Is_Primitive_Of --
---------------------
function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is
Formal : Entity_Id;
begin
-- If the full view is a scalar type, the type is the anonymous base
-- type, but the operation mentions the first subtype, so check the
-- signature against the base type.
if Base_Type (Etype (S)) = Base_Type (T) then
return True;
else
Formal := First_Formal (S);
while Present (Formal) loop
if Base_Type (Etype (Formal)) = Base_Type (T) then
return True;
end if;
Next_Formal (Formal);
end loop;
return False;
end if;
end Is_Primitive_Of;
-- Local variables
E : Entity_Id;
Op_List : Elist_Id;
Op_Elmt : Elmt_Id;
Op_Elmt_2 : Elmt_Id;
Prim_Op : Entity_Id;
New_Op : Entity_Id := Empty;
Parent_Subp : Entity_Id;
Tag : Entity_Id;
-- Start of processing for Declare_Inherited_Private_Subprograms
begin
E := First_Entity (Id);
while Present (E) loop
-- If the entity is a nonprivate type extension whose parent type
-- is declared in an open scope, then the type may have inherited
-- operations that now need to be made visible. Ditto if the entity
-- is a formal derived type in a child unit.
if ((Is_Derived_Type (E) and then not Is_Private_Type (E))
or else
(Nkind (Parent (E)) = N_Private_Extension_Declaration
and then Is_Generic_Type (E)))
and then In_Open_Scopes (Scope (Etype (E)))
and then Is_Base_Type (E)
then
if Is_Tagged_Type (E) then
Op_List := Primitive_Operations (E);
New_Op := Empty;
Tag := First_Tag_Component (E);
Op_Elmt := First_Elmt (Op_List);
while Present (Op_Elmt) loop
Prim_Op := Node (Op_Elmt);
-- Search primitives that are implicit operations with an
-- internal name whose parent operation has a normal name.
if Present (Alias (Prim_Op))
and then Find_Dispatching_Type (Alias (Prim_Op)) /= E
and then not Comes_From_Source (Prim_Op)
and then Is_Internal_Name (Chars (Prim_Op))
and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
then
Parent_Subp := Alias (Prim_Op);
-- Case 1: Check if the type has also an explicit
-- overriding for this primitive.
Op_Elmt_2 := Next_Elmt (Op_Elmt);
while Present (Op_Elmt_2) loop
-- Skip entities with attribute Interface_Alias since
-- they are not overriding primitives (these entities
-- link an interface primitive with their covering
-- primitive)
if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
and then No (Interface_Alias (Node (Op_Elmt_2)))
then
-- The private inherited operation has been
-- overridden by an explicit subprogram:
-- replace the former by the latter.
New_Op := Node (Op_Elmt_2);
Replace_Elmt (Op_Elmt, New_Op);
Remove_Elmt (Op_List, Op_Elmt_2);
Set_Overridden_Operation (New_Op, Parent_Subp);
Set_Is_Ada_2022_Only (New_Op,
Is_Ada_2022_Only (Parent_Subp));
-- We don't need to inherit its dispatching slot.
-- Set_All_DT_Position has previously ensured that
-- the same slot was assigned to the two primitives
if Present (Tag)
and then Present (DTC_Entity (New_Op))
and then Present (DTC_Entity (Prim_Op))
then
pragma Assert
(DT_Position (New_Op) = DT_Position (Prim_Op));
null;
end if;
goto Next_Primitive;
end if;
Next_Elmt (Op_Elmt_2);
end loop;
-- Case 2: We have not found any explicit overriding and
-- hence we need to declare the operation (i.e., make it
-- visible).
Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
-- Inherit the dispatching slot if E is already frozen
if Is_Frozen (E)
and then Present (DTC_Entity (Alias (Prim_Op)))
then
Set_DTC_Entity_Value (E, New_Op);
Set_DT_Position_Value (New_Op,
DT_Position (Alias (Prim_Op)));
end if;
pragma Assert
(Is_Dispatching_Operation (New_Op)
and then Node (Last_Elmt (Op_List)) = New_Op);
-- Substitute the new operation for the old one in the
-- type's primitive operations list. Since the new
-- operation was also just added to the end of list,
-- the last element must be removed.
-- (Question: is there a simpler way of declaring the
-- operation, say by just replacing the name of the
-- earlier operation, reentering it in the in the symbol
-- table (how?), and marking it as private???)
Replace_Elmt (Op_Elmt, New_Op);
Remove_Last_Elmt (Op_List);
end if;
<<Next_Primitive>>
Next_Elmt (Op_Elmt);
end loop;
-- Generate listing showing the contents of the dispatch table
if Debug_Flag_ZZ then
Write_DT (E);
end if;
else
-- For untagged type, scan forward to locate inherited hidden
-- operations.
Prim_Op := Next_Entity (E);
while Present (Prim_Op) loop
if Is_Subprogram (Prim_Op)
and then Present (Alias (Prim_Op))
and then not Comes_From_Source (Prim_Op)
and then Is_Internal_Name (Chars (Prim_Op))
and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
and then Is_Primitive_Of (E, Prim_Op)
then
Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
end if;
Next_Entity (Prim_Op);
-- Derived operations appear immediately after the type
-- declaration (or the following subtype indication for
-- a derived scalar type). Further declarations cannot
-- include inherited operations of the type.
exit when Present (Prim_Op)
and then not Is_Overloadable (Prim_Op);
end loop;
end if;
end if;
Next_Entity (E);
end loop;
end Declare_Inherited_Private_Subprograms;
-----------------------
-- End_Package_Scope --
-----------------------
procedure End_Package_Scope (P : Entity_Id) is
begin
Uninstall_Declarations (P);
Pop_Scope;
end End_Package_Scope;
---------------------------
-- Exchange_Declarations --
---------------------------
procedure Exchange_Declarations (Id : Entity_Id) is
Full_Id : constant Entity_Id := Full_View (Id);
H1 : constant Entity_Id := Homonym (Id);
Next1 : constant Entity_Id := Next_Entity (Id);
H2 : Entity_Id;
Next2 : Entity_Id;
begin
-- If missing full declaration for type, nothing to exchange
if No (Full_Id) then
return;
end if;
-- Otherwise complete the exchange, and preserve semantic links
Next2 := Next_Entity (Full_Id);
H2 := Homonym (Full_Id);
-- Reset full declaration pointer to reflect the switched entities and
-- readjust the next entity chains.
Exchange_Entities (Id, Full_Id);
Link_Entities (Id, Next1);
Set_Homonym (Id, H1);
Set_Full_View (Full_Id, Id);
Link_Entities (Full_Id, Next2);
Set_Homonym (Full_Id, H2);
end Exchange_Declarations;
----------------------------
-- Install_Package_Entity --
----------------------------
procedure Install_Package_Entity (Id : Entity_Id) is
begin
if not Is_Internal (Id) then
if Debug_Flag_E then
Write_Str ("Install: ");
Write_Name (Chars (Id));
Write_Eol;
end if;
if Is_Child_Unit (Id) then
null;
-- Do not enter implicitly inherited non-overridden subprograms of
-- a tagged type back into visibility if they have non-conformant
-- homographs (Ada RM 8.3 12.3/2).
elsif Is_Hidden_Non_Overridden_Subpgm (Id) then
null;
else
Set_Is_Immediately_Visible (Id);
end if;
end if;
end Install_Package_Entity;
----------------------------------
-- Install_Private_Declarations --
----------------------------------
procedure Install_Private_Declarations (P : Entity_Id) is
Id : Entity_Id;
Full : Entity_Id;
Priv_Deps : Elist_Id;
procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
-- When the full view of a private type is made available, we do the
-- same for its private dependents under proper visibility conditions.
-- When compiling a child unit this needs to be done recursively.
-----------------------------
-- Swap_Private_Dependents --
-----------------------------
procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
Cunit : Entity_Id;
Deps : Elist_Id;
Priv : Entity_Id;
Priv_Elmt : Elmt_Id;
Is_Priv : Boolean;
begin
Priv_Elmt := First_Elmt (Priv_Deps);
while Present (Priv_Elmt) loop
Priv := Node (Priv_Elmt);
-- Before the exchange, verify that the presence of the Full_View
-- field. This field will be empty if the entity has already been
-- installed due to a previous call.
if Present (Full_View (Priv)) and then Is_Visible_Dependent (Priv)
then
if Is_Private_Type (Priv) then
Cunit := Cunit_Entity (Current_Sem_Unit);
Deps := Private_Dependents (Priv);
Is_Priv := True;
else
Is_Priv := False;
end if;
-- For each subtype that is swapped, we also swap the reference
-- to it in Private_Dependents, to allow access to it when we
-- swap them out in End_Package_Scope.
Replace_Elmt (Priv_Elmt, Full_View (Priv));
-- Ensure that both views of the dependent private subtype are
-- immediately visible if within some open scope. Check full
-- view before exchanging views.
if In_Open_Scopes (Scope (Full_View (Priv))) then
Set_Is_Immediately_Visible (Priv);
end if;
Exchange_Declarations (Priv);
Set_Is_Immediately_Visible
(Priv, In_Open_Scopes (Scope (Priv)));
Set_Is_Potentially_Use_Visible
(Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt)));
-- Recurse for child units, except in generic child units,
-- which unfortunately handle private_dependents separately.
-- Note that the current unit may not have been analyzed,
-- for example a package body, so we cannot rely solely on
-- the Is_Child_Unit flag, but that's only an optimization.
if Is_Priv
and then (No (Etype (Cunit)) or else Is_Child_Unit (Cunit))
and then not Is_Empty_Elmt_List (Deps)
and then not Inside_A_Generic
then
Swap_Private_Dependents (Deps);
end if;
end if;
Next_Elmt (Priv_Elmt);
end loop;
end Swap_Private_Dependents;
-- Start of processing for Install_Private_Declarations
begin
-- First exchange declarations for private types, so that the full
-- declaration is visible. For each private type, we check its
-- Private_Dependents list and also exchange any subtypes of or derived
-- types from it. Finally, if this is a Taft amendment type, the
-- incomplete declaration is irrelevant, and we want to link the
-- eventual full declaration with the original private one so we
-- also skip the exchange.
Id := First_Entity (P);
while Present (Id) and then Id /= First_Private_Entity (P) loop
if Is_Private_Base_Type (Id)
and then Present (Full_View (Id))
and then Comes_From_Source (Full_View (Id))
and then Scope (Full_View (Id)) = Scope (Id)
and then Ekind (Full_View (Id)) /= E_Incomplete_Type
then
-- If there is a use-type clause on the private type, set the full
-- view accordingly.
Set_In_Use (Full_View (Id), In_Use (Id));
Full := Full_View (Id);
if Is_Private_Base_Type (Full)
and then Has_Private_Declaration (Full)
and then Nkind (Parent (Full)) = N_Full_Type_Declaration
and then In_Open_Scopes (Scope (Etype (Full)))
and then In_Package_Body (Current_Scope)
and then not Is_Private_Type (Etype (Full))
then
-- This is the completion of a private type by a derivation
-- from another private type which is not private anymore. This
-- can only happen in a package nested within a child package,
-- when the parent type is defined in the parent unit. At this
-- point the current type is not private either, and we have
-- to install the underlying full view, which is now visible.
-- Save the current full view as well, so that all views can be
-- restored on exit. It may seem that after compiling the child
-- body there are not environments to restore, but the back-end
-- expects those links to be valid, and freeze nodes depend on
-- them.
if No (Full_View (Full))
and then Present (Underlying_Full_View (Full))
then
Set_Full_View (Id, Underlying_Full_View (Full));
Set_Underlying_Full_View (Id, Full);
Set_Is_Underlying_Full_View (Full);
Set_Underlying_Full_View (Full, Empty);
Set_Is_Frozen (Full_View (Id));
end if;
end if;
Priv_Deps := Private_Dependents (Id);
Exchange_Declarations (Id);
Set_Is_Immediately_Visible (Id);
Swap_Private_Dependents (Priv_Deps);
end if;
Next_Entity (Id);
end loop;
-- Next make other declarations in the private part visible as well
Id := First_Private_Entity (P);
while Present (Id) loop
Install_Package_Entity (Id);
Set_Is_Hidden (Id, False);
Next_Entity (Id);
end loop;
-- An abstract state is partially refined when it has at least one
-- Part_Of constituent. Since these constituents are being installed
-- into visibility, update the partial refinement status of any state
-- defined in the associated package, subject to at least one Part_Of
-- constituent.
if Is_Package_Or_Generic_Package (P) then
declare
States : constant Elist_Id := Abstract_States (P);
State_Elmt : Elmt_Id;
State_Id : Entity_Id;
begin
if Present (States) then
State_Elmt := First_Elmt (States);
while Present (State_Elmt) loop
State_Id := Node (State_Elmt);
if Present (Part_Of_Constituents (State_Id)) then
Set_Has_Partial_Visible_Refinement (State_Id);
end if;
Next_Elmt (State_Elmt);
end loop;
end if;
end;
end if;
-- Indicate that the private part is currently visible, so it can be
-- properly reset on exit.
Set_In_Private_Part (P);
end Install_Private_Declarations;
----------------------------------
-- Install_Visible_Declarations --
----------------------------------
procedure Install_Visible_Declarations (P : Entity_Id) is
Id : Entity_Id;
Last_Entity : Entity_Id;
begin
pragma Assert
(Is_Package_Or_Generic_Package (P) or else Is_Record_Type (P));
if Is_Package_Or_Generic_Package (P) then
Last_Entity := First_Private_Entity (P);
else
Last_Entity := Empty;
end if;
Id := First_Entity (P);
while Present (Id) and then Id /= Last_Entity loop
Install_Package_Entity (Id);
Next_Entity (Id);
end loop;
end Install_Visible_Declarations;
--------------------------
-- Is_Private_Base_Type --
--------------------------
function Is_Private_Base_Type (E : Entity_Id) return Boolean is
begin
return Ekind (E) = E_Private_Type
or else Ekind (E) = E_Limited_Private_Type
or else Ekind (E) = E_Record_Type_With_Private;
end Is_Private_Base_Type;
--------------------------
-- Is_Visible_Dependent --
--------------------------
function Is_Visible_Dependent (Dep : Entity_Id) return Boolean
is
S : constant Entity_Id := Scope (Dep);
begin
-- Renamings created for actual types have the visibility of the actual
if Ekind (S) = E_Package
and then Is_Generic_Instance (S)
and then (Is_Generic_Actual_Type (Dep)
or else Is_Generic_Actual_Type (Full_View (Dep)))
then
return True;
elsif not (Is_Derived_Type (Dep))
and then Is_Derived_Type (Full_View (Dep))
then
-- When instantiating a package body, the scope stack is empty, so
-- check instead whether the dependent type is defined in the same
-- scope as the instance itself.
return In_Open_Scopes (S)
or else (Is_Generic_Instance (Current_Scope)
and then Scope (Dep) = Scope (Current_Scope));
else
return True;
end if;
end Is_Visible_Dependent;
----------------------------
-- May_Need_Implicit_Body --
----------------------------
procedure May_Need_Implicit_Body (E : Entity_Id) is
P : constant Node_Id := Unit_Declaration_Node (E);
S : constant Node_Id := Parent (P);
B : Node_Id;
Decls : List_Id;
begin
if not Has_Completion (E)
and then Nkind (P) = N_Package_Declaration
and then (Present (Activation_Chain_Entity (P)) or else Has_RACW (E))
then
B :=
Make_Package_Body (Sloc (E),
Defining_Unit_Name => Make_Defining_Identifier (Sloc (E),
Chars => Chars (E)),
Declarations => New_List);
if Nkind (S) = N_Package_Specification then
if Present (Private_Declarations (S)) then
Decls := Private_Declarations (S);
else
Decls := Visible_Declarations (S);
end if;
else
Decls := Declarations (S);
end if;
Append (B, Decls);
Analyze (B);
end if;
end May_Need_Implicit_Body;
----------------------
-- New_Private_Type --
----------------------
procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is
begin
-- For other than Ada 2012, enter the name in the current scope
if Ada_Version < Ada_2012 then
Enter_Name (Id);
-- Ada 2012 (AI05-0162): Enter the name in the current scope. Note that
-- there may be an incomplete previous view.
else
declare
Prev : Entity_Id;
begin
Prev := Find_Type_Name (N);
pragma Assert (Prev = Id
or else (Ekind (Prev) = E_Incomplete_Type
and then Present (Full_View (Prev))
and then Full_View (Prev) = Id));
end;
end if;
if Limited_Present (Def) then
Mutate_Ekind (Id, E_Limited_Private_Type);
else
Mutate_Ekind (Id, E_Private_Type);
end if;
Set_Etype (Id, Id);
Set_Has_Delayed_Freeze (Id);
Set_Is_First_Subtype (Id);
Reinit_Size_Align (Id);
Set_Is_Constrained (Id,
No (Discriminant_Specifications (N))
and then not Unknown_Discriminants_Present (N));
-- Set tagged flag before processing discriminants, to catch illegal
-- usage.
Set_Is_Tagged_Type (Id, Tagged_Present (Def));
Set_Discriminant_Constraint (Id, No_Elist);
Set_Stored_Constraint (Id, No_Elist);
if Present (Discriminant_Specifications (N)) then
Push_Scope (Id);
Process_Discriminants (N);
End_Scope;
elsif Unknown_Discriminants_Present (N) then
Set_Has_Unknown_Discriminants (Id);
end if;
Set_Private_Dependents (Id, New_Elmt_List);
if Tagged_Present (Def) then
Mutate_Ekind (Id, E_Record_Type_With_Private);
Set_Direct_Primitive_Operations (Id, New_Elmt_List);
Set_Is_Abstract_Type (Id, Abstract_Present (Def));
Set_Is_Limited_Record (Id, Limited_Present (Def));
Set_Has_Delayed_Freeze (Id, True);
-- Recognize Ada.Real_Time.Timing_Events.Timing_Events here
if Is_RTE (Id, RE_Timing_Event) then
Set_Has_Timing_Event (Id);
end if;
-- Create a class-wide type with the same attributes
Make_Class_Wide_Type (Id);
elsif Abstract_Present (Def) then
Error_Msg_N ("only a tagged type can be abstract", N);
-- We initialize the primitive operations list of an untagged private
-- type to an empty element list. Do this even when Extensions_Allowed
-- is False to issue better error messages. (Note: This could be done
-- for all private types and shared with the tagged case above, but
-- for now we do it separately.)
else
Set_Direct_Primitive_Operations (Id, New_Elmt_List);
end if;
end New_Private_Type;
---------------------------------
-- Requires_Completion_In_Body --
---------------------------------
function Requires_Completion_In_Body
(Id : Entity_Id;
Pack_Id : Entity_Id;
Do_Abstract_States : Boolean := False) return Boolean
is
begin
-- Always ignore child units. Child units get added to the entity list
-- of a parent unit, but are not original entities of the parent, and
-- so do not affect whether the parent needs a body.
if Is_Child_Unit (Id) then
return False;
-- Ignore formal packages and their renamings
elsif Ekind (Id) = E_Package
and then Nkind (Original_Node (Unit_Declaration_Node (Id))) =
N_Formal_Package_Declaration
then
return False;
-- Otherwise test to see if entity requires a completion. Note that
-- subprogram entities whose declaration does not come from source are
-- ignored here on the basis that we assume the expander will provide an
-- implicit completion at some point.
elsif (Is_Overloadable (Id)
and then Ekind (Id) not in E_Enumeration_Literal | E_Operator
and then not Is_Abstract_Subprogram (Id)
and then not Has_Completion (Id)
and then Comes_From_Source (Parent (Id)))
or else
(Ekind (Id) = E_Package
and then Id /= Pack_Id
and then not Has_Completion (Id)
and then Unit_Requires_Body (Id, Do_Abstract_States))
or else
(Ekind (Id) = E_Incomplete_Type
and then No (Full_View (Id))
and then not Is_Generic_Type (Id))
or else
(Ekind (Id) in E_Task_Type | E_Protected_Type
and then not Has_Completion (Id))
or else
(Ekind (Id) = E_Generic_Package
and then Id /= Pack_Id
and then not Has_Completion (Id)
and then Unit_Requires_Body (Id, Do_Abstract_States))
or else
(Is_Generic_Subprogram (Id)
and then not Has_Completion (Id))
then
return True;
-- Otherwise the entity does not require completion in a package body
else
return False;
end if;
end Requires_Completion_In_Body;
----------------------------
-- Uninstall_Declarations --
----------------------------
procedure Uninstall_Declarations (P : Entity_Id) is
Decl : constant Node_Id := Unit_Declaration_Node (P);
Id : Entity_Id;
Full : Entity_Id;
procedure Preserve_Full_Attributes (Priv : Entity_Id; Full : Entity_Id);
-- Copy to the private declaration the attributes of the full view that
-- need to be available for the partial view also.
procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
-- When the full view of a private type is made unavailable, we do the
-- same for its private dependents under proper visibility conditions.
-- When compiling a child unit this needs to be done recursively.
function Type_In_Use (T : Entity_Id) return Boolean;
-- Check whether type or base type appear in an active use_type clause
------------------------------
-- Preserve_Full_Attributes --
------------------------------
procedure Preserve_Full_Attributes
(Priv : Entity_Id;
Full : Entity_Id)
is
Full_Base : constant Entity_Id := Base_Type (Full);
Priv_Is_Base_Type : constant Boolean := Is_Base_Type (Priv);
begin
Set_Size_Info (Priv, Full);
Copy_RM_Size (To => Priv, From => Full);
Set_Size_Known_At_Compile_Time
(Priv, Size_Known_At_Compile_Time (Full));
Set_Is_Volatile (Priv, Is_Volatile (Full));
Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full));
Set_Is_Atomic (Priv, Is_Atomic (Full));
Set_Is_Ada_2005_Only (Priv, Is_Ada_2005_Only (Full));
Set_Is_Ada_2012_Only (Priv, Is_Ada_2012_Only (Full));
Set_Is_Ada_2022_Only (Priv, Is_Ada_2022_Only (Full));
Set_Has_Pragma_Unmodified (Priv, Has_Pragma_Unmodified (Full));
Set_Has_Pragma_Unreferenced (Priv, Has_Pragma_Unreferenced (Full));
Set_Has_Pragma_Unreferenced_Objects
(Priv, Has_Pragma_Unreferenced_Objects
(Full));
Set_Predicates_Ignored (Priv, Predicates_Ignored (Full));
if Is_Unchecked_Union (Full) then
Set_Is_Unchecked_Union (Base_Type (Priv));
end if;
if Referenced (Full) then
Set_Referenced (Priv);
end if;
if Priv_Is_Base_Type then
Set_Is_Controlled_Active
(Priv, Is_Controlled_Active (Full_Base));
Set_Finalize_Storage_Only
(Priv, Finalize_Storage_Only (Full_Base));
Set_Has_Controlled_Component
(Priv, Has_Controlled_Component (Full_Base));
Propagate_Concurrent_Flags (Priv, Base_Type (Full));
end if;
-- As explained in Freeze_Entity, private types are required to point
-- to the same freeze node as their corresponding full view, if any.
-- But we ought not to overwrite a node already inserted in the tree.
pragma Assert
(Serious_Errors_Detected /= 0
or else No (Freeze_Node (Priv))
or else No (Parent (Freeze_Node (Priv)))
or else Freeze_Node (Priv) = Freeze_Node (Full));
Set_Freeze_Node (Priv, Freeze_Node (Full));
-- Propagate Default_Initial_Condition-related attributes from the
-- full view to the private view.
Propagate_DIC_Attributes (Priv, From_Typ => Full);
-- Propagate invariant-related attributes from the full view to the
-- private view.
Propagate_Invariant_Attributes (Priv, From_Typ => Full);
-- Propagate predicate-related attributes from the full view to the
-- private view.
Propagate_Predicate_Attributes (Priv, From_Typ => Full);
if Is_Tagged_Type (Priv)
and then Is_Tagged_Type (Full)
and then not Error_Posted (Full)
then
if Is_Tagged_Type (Priv) then
-- If the type is tagged, the tag itself must be available on
-- the partial view, for expansion purposes.
Set_First_Entity (Priv, First_Entity (Full));
-- If there are discriminants in the partial view, these remain
-- visible. Otherwise only the tag itself is visible, and there
-- are no nameable components in the partial view.
if No (Last_Entity (Priv)) then
Set_Last_Entity (Priv, First_Entity (Priv));
end if;
end if;
Set_Has_Discriminants (Priv, Has_Discriminants (Full));
if Has_Discriminants (Full) then
Set_Discriminant_Constraint (Priv,
Discriminant_Constraint (Full));
end if;
end if;
end Preserve_Full_Attributes;
-----------------------------
-- Swap_Private_Dependents --
-----------------------------
procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
Cunit : Entity_Id;
Deps : Elist_Id;
Priv : Entity_Id;
Priv_Elmt : Elmt_Id;
Is_Priv : Boolean;
begin
Priv_Elmt := First_Elmt (Priv_Deps);
while Present (Priv_Elmt) loop
Priv := Node (Priv_Elmt);
-- Before we do the swap, we verify the presence of the Full_View
-- field, which may be empty due to a swap by a previous call to
-- End_Package_Scope (e.g. from the freezing mechanism).
if Present (Full_View (Priv)) then
if Is_Private_Type (Priv) then
Cunit := Cunit_Entity (Current_Sem_Unit);
Deps := Private_Dependents (Priv);
Is_Priv := True;
else
Is_Priv := False;
end if;
if Scope (Priv) = P
or else not In_Open_Scopes (Scope (Priv))
then
Set_Is_Immediately_Visible (Priv, False);
end if;
if Is_Visible_Dependent (Priv) then
Preserve_Full_Attributes (Priv, Full_View (Priv));
Replace_Elmt (Priv_Elmt, Full_View (Priv));
Exchange_Declarations (Priv);
-- Recurse for child units, except in generic child units,
-- which unfortunately handle private_dependents separately.
-- Note that the current unit may not have been analyzed,
-- for example a package body, so we cannot rely solely on
-- the Is_Child_Unit flag, but that's only an optimization.
if Is_Priv
and then (No (Etype (Cunit)) or else Is_Child_Unit (Cunit))
and then not Is_Empty_Elmt_List (Deps)
and then not Inside_A_Generic
then
Swap_Private_Dependents (Deps);
end if;
end if;
end if;
Next_Elmt (Priv_Elmt);
end loop;
end Swap_Private_Dependents;
-----------------
-- Type_In_Use --
-----------------
function Type_In_Use (T : Entity_Id) return Boolean is
begin
return Scope (Base_Type (T)) = P
and then (In_Use (T) or else In_Use (Base_Type (T)));
end Type_In_Use;
-- Start of processing for Uninstall_Declarations
begin
Id := First_Entity (P);
while Present (Id) and then Id /= First_Private_Entity (P) loop
if Debug_Flag_E then
Write_Str ("unlinking visible entity ");
Write_Int (Int (Id));
Write_Eol;
end if;
-- On exit from the package scope, we must preserve the visibility
-- established by use clauses in the current scope. Two cases:
-- a) If the entity is an operator, it may be a primitive operator of
-- a type for which there is a visible use-type clause.
-- b) For other entities, their use-visibility is determined by a
-- visible use clause for the package itself or a use-all-type clause
-- applied directly to the entity's type. For a generic instance,
-- the instantiation of the formals appears in the visible part,
-- but the formals are private and remain so.
if Ekind (Id) = E_Function
and then Is_Operator_Symbol_Name (Chars (Id))
and then not Is_Hidden (Id)
and then not Error_Posted (Id)
then
Set_Is_Potentially_Use_Visible (Id,
In_Use (P)
or else Type_In_Use (Etype (Id))
or else Type_In_Use (Etype (First_Formal (Id)))
or else (Present (Next_Formal (First_Formal (Id)))
and then
Type_In_Use
(Etype (Next_Formal (First_Formal (Id))))));
else
if In_Use (P) and then not Is_Hidden (Id) then
-- A child unit of a use-visible package remains use-visible
-- only if it is itself a visible child unit. Otherwise it
-- would remain visible in other contexts where P is use-
-- visible, because once compiled it stays in the entity list
-- of its parent unit.
if Is_Child_Unit (Id) then
Set_Is_Potentially_Use_Visible
(Id, Is_Visible_Lib_Unit (Id));
else
Set_Is_Potentially_Use_Visible (Id);
end if;
-- Avoid crash caused by previous errors
elsif No (Etype (Id)) and then Serious_Errors_Detected /= 0 then
null;
-- We need to avoid incorrectly marking enumeration literals as
-- non-visible when a visible use-all-type clause is in effect.
elsif Type_In_Use (Etype (Id))
and then Nkind (Current_Use_Clause (Etype (Id))) =
N_Use_Type_Clause
and then All_Present (Current_Use_Clause (Etype (Id)))
then
null;
else
Set_Is_Potentially_Use_Visible (Id, False);
end if;
end if;
-- Local entities are not immediately visible outside of the package
Set_Is_Immediately_Visible (Id, False);
-- If this is a private type with a full view (for example a local
-- subtype of a private type declared elsewhere), ensure that the
-- full view is also removed from visibility: it may be exposed when
-- swapping views in an instantiation. Similarly, ensure that the
-- use-visibility is properly set on both views.
if Is_Type (Id) and then Present (Full_View (Id)) then
Set_Is_Immediately_Visible (Full_View (Id), False);
Set_Is_Potentially_Use_Visible (Full_View (Id),
Is_Potentially_Use_Visible (Id));
end if;
if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
Check_Abstract_Overriding (Id);
Check_Conventions (Id);
end if;
if Ekind (Id) in E_Private_Type | E_Limited_Private_Type
and then No (Full_View (Id))
and then not Is_Generic_Type (Id)
and then not Is_Derived_Type (Id)
then
Error_Msg_N ("missing full declaration for private type&", Id);
elsif Ekind (Id) = E_Record_Type_With_Private
and then not Is_Generic_Type (Id)
and then No (Full_View (Id))
then
if Nkind (Parent (Id)) = N_Private_Type_Declaration then
Error_Msg_N ("missing full declaration for private type&", Id);
else
Error_Msg_N
("missing full declaration for private extension", Id);
end if;
-- Case of constant, check for deferred constant declaration with
-- no full view. Likely just a matter of a missing expression, or
-- accidental use of the keyword constant.
elsif Ekind (Id) = E_Constant
-- OK if constant value present
and then No (Constant_Value (Id))
-- OK if full view present
and then No (Full_View (Id))
-- OK if imported, since that provides the completion
and then not Is_Imported (Id)
-- OK if object declaration replaced by renaming declaration as
-- a result of OK_To_Rename processing (e.g. for concatenation)
and then Nkind (Parent (Id)) /= N_Object_Renaming_Declaration
-- OK if object declaration with the No_Initialization flag set
and then not (Nkind (Parent (Id)) = N_Object_Declaration
and then No_Initialization (Parent (Id)))
then
-- If no private declaration is present, we assume the user did
-- not intend a deferred constant declaration and the problem
-- is simply that the initializing expression is missing.
if not Has_Private_Declaration (Etype (Id)) then
-- We assume that the user did not intend a deferred constant
-- declaration, and the expression is just missing.
Error_Msg_N
("constant declaration requires initialization expression",
Parent (Id));
if Is_Limited_Type (Etype (Id)) then
Error_Msg_N
("\if variable intended, remove CONSTANT from declaration",
Parent (Id));
end if;
-- Otherwise if a private declaration is present, then we are
-- missing the full declaration for the deferred constant.
else
Error_Msg_N
("missing full declaration for deferred constant (RM 7.4)",
Id);
if Is_Limited_Type (Etype (Id)) then
Error_Msg_N
("\if variable intended, remove CONSTANT from declaration",
Parent (Id));
end if;
end if;
end if;
Next_Entity (Id);
end loop;
-- If the specification was installed as the parent of a public child
-- unit, the private declarations were not installed, and there is
-- nothing to do.
if not In_Private_Part (P) then
return;
end if;
-- Reset the flag now
Set_In_Private_Part (P, False);
-- Make private entities invisible and exchange full and private
-- declarations for private types. Id is now the first private entity
-- in the package.
while Present (Id) loop
if Debug_Flag_E then
Write_Str ("unlinking private entity ");
Write_Int (Int (Id));
Write_Eol;
end if;
if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
Check_Abstract_Overriding (Id);
Check_Conventions (Id);
end if;
Set_Is_Immediately_Visible (Id, False);
if Is_Private_Base_Type (Id) and then Present (Full_View (Id)) then
Full := Full_View (Id);
-- If the partial view is not declared in the visible part of the
-- package (as is the case when it is a type derived from some
-- other private type in the private part of the current package),
-- no exchange takes place.
if No (Parent (Id))
or else List_Containing (Parent (Id)) /=
Visible_Declarations (Specification (Decl))
then
goto Next_Id;
end if;
-- The entry in the private part points to the full declaration,
-- which is currently visible. Exchange them so only the private
-- type declaration remains accessible, and link private and full
-- declaration in the opposite direction. Before the actual
-- exchange, we copy back attributes of the full view that must
-- be available to the partial view too.
Preserve_Full_Attributes (Id, Full);
Set_Is_Potentially_Use_Visible (Id, In_Use (P));
-- The following test may be redundant, as this is already
-- diagnosed in sem_ch3. ???
if not Is_Definite_Subtype (Full)
and then Is_Definite_Subtype (Id)
then
Error_Msg_Sloc := Sloc (Parent (Id));
Error_Msg_NE
("full view of& not compatible with declaration#", Full, Id);
end if;
-- Swap out the subtypes and derived types of Id that
-- were compiled in this scope, or installed previously
-- by Install_Private_Declarations.
Swap_Private_Dependents (Private_Dependents (Id));
-- Now restore the type itself to its private view
Exchange_Declarations (Id);
-- If we have installed an underlying full view for a type derived
-- from a private type in a child unit, restore the proper views
-- of private and full view. See corresponding code in
-- Install_Private_Declarations.
-- After the exchange, Full denotes the private type in the
-- visible part of the package.
if Is_Private_Base_Type (Full)
and then Present (Full_View (Full))
and then Present (Underlying_Full_View (Full))
and then In_Package_Body (Current_Scope)
then
Set_Full_View (Full, Underlying_Full_View (Full));
Set_Underlying_Full_View (Full, Empty);
end if;
elsif Ekind (Id) = E_Incomplete_Type
and then Comes_From_Source (Id)
and then No (Full_View (Id))
then
-- Mark Taft amendment types. Verify that there are no primitive
-- operations declared for the type (3.10.1(9)).
Set_Has_Completion_In_Body (Id);
declare
Elmt : Elmt_Id;
Subp : Entity_Id;
begin
Elmt := First_Elmt (Private_Dependents (Id));
while Present (Elmt) loop
Subp := Node (Elmt);
-- Is_Primitive is tested because there can be cases where
-- nonprimitive subprograms (in nested packages) are added
-- to the Private_Dependents list.
if Is_Overloadable (Subp) and then Is_Primitive (Subp) then
Error_Msg_NE
("type& must be completed in the private part",
Parent (Subp), Id);
-- The result type of an access-to-function type cannot be a
-- Taft-amendment type, unless the version is Ada 2012 or
-- later (see AI05-151).
elsif Ada_Version < Ada_2012
and then Ekind (Subp) = E_Subprogram_Type
then
if Etype (Subp) = Id
or else
(Is_Class_Wide_Type (Etype (Subp))
and then Etype (Etype (Subp)) = Id)
then
Error_Msg_NE
("type& must be completed in the private part",
Associated_Node_For_Itype (Subp), Id);
end if;
end if;
Next_Elmt (Elmt);
end loop;
end;
-- For subtypes of private types the frontend generates two entities:
-- one associated with the partial view and the other associated with
-- the full view. When the subtype declaration is public the frontend
-- places the former entity in the list of public entities of the
-- package and the latter entity in the private part of the package.
-- When the subtype declaration is private it generates these two
-- entities but both are placed in the private part of the package
-- (and the full view has the same source location as the partial
-- view and no parent; see Prepare_Private_Subtype_Completion).
elsif Ekind (Id) in E_Private_Subtype
| E_Limited_Private_Subtype
and then Present (Full_View (Id))
and then Sloc (Id) = Sloc (Full_View (Id))
and then No (Parent (Full_View (Id)))
then
Set_Is_Hidden (Id);
Set_Is_Potentially_Use_Visible (Id, False);
elsif not Is_Child_Unit (Id)
and then (not Is_Private_Type (Id) or else No (Full_View (Id)))
then
Set_Is_Hidden (Id);
Set_Is_Potentially_Use_Visible (Id, False);
end if;
<<Next_Id>>
Next_Entity (Id);
end loop;
end Uninstall_Declarations;
------------------------
-- Unit_Requires_Body --
------------------------
function Unit_Requires_Body
(Pack_Id : Entity_Id;
Do_Abstract_States : Boolean := False) return Boolean
is
E : Entity_Id;
Requires_Body : Boolean := False;
-- Flag set when the unit has at least one construct that requires
-- completion in a body.
begin
-- Imported entity never requires body. Right now, only subprograms can
-- be imported, but perhaps in the future we will allow import of
-- packages.
if Is_Imported (Pack_Id) then
return False;
-- Body required if library package with pragma Elaborate_Body
elsif Has_Pragma_Elaborate_Body (Pack_Id) then
return True;
-- Body required if subprogram
elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
return True;
-- Treat a block as requiring a body
elsif Ekind (Pack_Id) = E_Block then
return True;
elsif Ekind (Pack_Id) = E_Package
and then Nkind (Parent (Pack_Id)) = N_Package_Specification
and then Present (Generic_Parent (Parent (Pack_Id)))
then
declare
G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
begin
if Has_Pragma_Elaborate_Body (G_P) then
return True;
end if;
end;
end if;
-- Traverse the entity chain of the package and look for constructs that
-- require a completion in a body.
E := First_Entity (Pack_Id);
while Present (E) loop
-- Skip abstract states because their completion depends on several
-- criteria (see below).
if Ekind (E) = E_Abstract_State then
null;
elsif Requires_Completion_In_Body
(E, Pack_Id, Do_Abstract_States)
then
Requires_Body := True;
exit;
end if;
Next_Entity (E);
end loop;
-- A [generic] package that defines at least one non-null abstract state
-- requires a completion only when at least one other construct requires
-- a completion in a body (SPARK RM 7.1.4(4) and (5)). This check is not
-- performed if the caller requests this behavior.
if Do_Abstract_States
and then Is_Package_Or_Generic_Package (Pack_Id)
and then Has_Non_Null_Abstract_State (Pack_Id)
and then Requires_Body
then
return True;
end if;
return Requires_Body;
end Unit_Requires_Body;
-----------------------------
-- Unit_Requires_Body_Info --
-----------------------------
procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id) is
E : Entity_Id;
begin
-- An imported entity never requires body. Right now, only subprograms
-- can be imported, but perhaps in the future we will allow import of
-- packages.
if Is_Imported (Pack_Id) then
return;
-- Body required if library package with pragma Elaborate_Body
elsif Has_Pragma_Elaborate_Body (Pack_Id) then
Error_Msg_N ("info: & requires body (Elaborate_Body)?.y?", Pack_Id);
-- Body required if subprogram
elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
Error_Msg_N ("info: & requires body (subprogram case)?.y?", Pack_Id);
-- Body required if generic parent has Elaborate_Body
elsif Ekind (Pack_Id) = E_Package
and then Nkind (Parent (Pack_Id)) = N_Package_Specification
and then Present (Generic_Parent (Parent (Pack_Id)))
then
declare
G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
begin
if Has_Pragma_Elaborate_Body (G_P) then
Error_Msg_N
("info: & requires body (generic parent Elaborate_Body)?.y?",
Pack_Id);
end if;
end;
-- A [generic] package that introduces at least one non-null abstract
-- state requires completion. However, there is a separate rule that
-- requires that such a package have a reason other than this for a
-- body being required (if necessary a pragma Elaborate_Body must be
-- provided). If Ignore_Abstract_State is True, we don't do this check
-- (so we can use Unit_Requires_Body to check for some other reason).
elsif Is_Package_Or_Generic_Package (Pack_Id)
and then Present (Abstract_States (Pack_Id))
and then not Is_Null_State
(Node (First_Elmt (Abstract_States (Pack_Id))))
then
Error_Msg_N
("info: & requires body (non-null abstract state aspect)?.y?",
Pack_Id);
end if;
-- Otherwise search entity chain for entity requiring completion
E := First_Entity (Pack_Id);
while Present (E) loop
if Requires_Completion_In_Body (E, Pack_Id) then
Error_Msg_Node_2 := E;
Error_Msg_NE
("info: & requires body (& requires completion)?.y?", E,
Pack_Id);
end if;
Next_Entity (E);
end loop;
end Unit_Requires_Body_Info;
end Sem_Ch7;