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gnu / gcc / 19220ca6aa79921cc431e41f25986e16410c7a6a / . / gcc / ada / sem_ch10.adb
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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S E M _ C H 1 0 --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2003 Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, USA. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
with Atree; use Atree;
with Debug; use Debug;
with Einfo; use Einfo;
with Errout; use Errout;
with Elists; use Elists;
with Exp_Util; use Exp_Util;
with Fname; use Fname;
with Fname.UF; use Fname.UF;
with Freeze; use Freeze;
with Impunit; use Impunit;
with Inline; use Inline;
with Lib; use Lib;
with Lib.Load; use Lib.Load;
with Lib.Xref; use Lib.Xref;
with Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Output; use Output;
with Restrict; use Restrict;
with Sem; use Sem;
with Sem_Ch6; use Sem_Ch6;
with Sem_Ch7; use Sem_Ch7;
with Sem_Ch8; use Sem_Ch8;
with Sem_Dist; use Sem_Dist;
with Sem_Prag; use Sem_Prag;
with Sem_Util; use Sem_Util;
with Sem_Warn; use Sem_Warn;
with Stand; use Stand;
with Sinfo; use Sinfo;
with Sinfo.CN; use Sinfo.CN;
with Sinput; use Sinput;
with Snames; use Snames;
with Style; use Style;
with Stylesw; use Stylesw;
with Tbuild; use Tbuild;
with Ttypes; use Ttypes;
with Uname; use Uname;
package body Sem_Ch10 is
-----------------------
-- Local Subprograms --
-----------------------
procedure Analyze_Context (N : Node_Id);
-- Analyzes items in the context clause of compilation unit
procedure Build_Limited_Views (N : Node_Id);
-- Build and decorate the list of shadow entities for a package mentioned
-- in a limited_with clause. If the package was not previously analyzed
-- then it also performs a basic decoration of the real entities; this
-- is required to do not pass non-decorated entities to the back-end.
-- Implements Ada0Y (AI-50217).
procedure Check_Body_Needed_For_SAL (Unit_Name : Entity_Id);
-- Check whether the source for the body of a compilation unit must
-- be included in a standalone library.
procedure Check_With_Type_Clauses (N : Node_Id);
-- If N is a body, verify that any with_type clauses on the spec, or
-- on the spec of any parent, have a matching with_clause.
procedure Check_Private_Child_Unit (N : Node_Id);
-- If a with_clause mentions a private child unit, the compilation
-- unit must be a member of the same family, as described in 10.1.2 (8).
procedure Check_Stub_Level (N : Node_Id);
-- Verify that a stub is declared immediately within a compilation unit,
-- and not in an inner frame.
procedure Expand_Limited_With_Clause (Nam : Node_Id; N : Node_Id);
-- If a child unit appears in a limited_with clause, there are implicit
-- limited_with clauses on all parents that are not already visible
-- through a regular with clause. This procedure creates the implicit
-- limited with_clauses for the parents and loads the corresponding units.
-- The shadow entities are created when the inserted clause is analyzed.
-- Implements Ada0Y (AI-50217).
procedure Expand_With_Clause (Nam : Node_Id; N : Node_Id);
-- When a child unit appears in a context clause, the implicit withs on
-- parents are made explicit, and with clauses are inserted in the context
-- clause before the one for the child. If a parent in the with_clause
-- is a renaming, the implicit with_clause is on the renaming whose name
-- is mentioned in the with_clause, and not on the package it renames.
-- N is the compilation unit whose list of context items receives the
-- implicit with_clauses.
function Get_Parent_Entity (Unit : Node_Id) return Entity_Id;
-- Get defining entity of parent unit of a child unit. In most cases this
-- is the defining entity of the unit, but for a child instance whose
-- parent needs a body for inlining, the instantiation node of the parent
-- has not yet been rewritten as a package declaration, and the entity has
-- to be retrieved from the Instance_Spec of the unit.
procedure Implicit_With_On_Parent (Child_Unit : Node_Id; N : Node_Id);
-- If the main unit is a child unit, implicit withs are also added for
-- all its ancestors.
procedure Install_Context_Clauses (N : Node_Id);
-- Subsidiary to previous one. Process only with_ and use_clauses for
-- current unit and its library unit if any.
procedure Install_Limited_Context_Clauses (N : Node_Id);
-- Subsidiary to Install_Context. Process only limited with_clauses
-- for current unit. Implements Ada0Y (AI-50217).
procedure Install_Limited_Withed_Unit (N : Node_Id);
-- Place shadow entities for a limited_with package in the visibility
-- structures for the current compilation. Implements Ada0Y (AI-50217).
procedure Install_Withed_Unit (With_Clause : Node_Id);
-- If the unit is not a child unit, make unit immediately visible.
-- The caller ensures that the unit is not already currently installed.
procedure Install_Parents (Lib_Unit : Node_Id; Is_Private : Boolean);
-- This procedure establishes the context for the compilation of a child
-- unit. If Lib_Unit is a child library spec then the context of the parent
-- is installed, and the parent itself made immediately visible, so that
-- the child unit is processed in the declarative region of the parent.
-- Install_Parents makes a recursive call to itself to ensure that all
-- parents are loaded in the nested case. If Lib_Unit is a library body,
-- the only effect of Install_Parents is to install the private decls of
-- the parents, because the visible parent declarations will have been
-- installed as part of the context of the corresponding spec.
procedure Install_Siblings (U_Name : Entity_Id; N : Node_Id);
-- In the compilation of a child unit, a child of any of the ancestor
-- units is directly visible if it is visible, because the parent is in
-- an enclosing scope. Iterate over context to find child units of U_Name
-- or of some ancestor of it.
function Is_Child_Spec (Lib_Unit : Node_Id) return Boolean;
-- Lib_Unit is a library unit which may be a spec or a body. Is_Child_Spec
-- returns True if Lib_Unit is a library spec which is a child spec, i.e.
-- a library spec that has a parent. If the call to Is_Child_Spec returns
-- True, then Parent_Spec (Lib_Unit) is non-Empty and points to the
-- compilation unit for the parent spec.
--
-- Lib_Unit can also be a subprogram body that acts as its own spec. If
-- the Parent_Spec is non-empty, this is also a child unit.
procedure Remove_With_Type_Clause (Name : Node_Id);
-- Remove imported type and its enclosing package from visibility, and
-- remove attributes of imported type so they don't interfere with its
-- analysis (should it appear otherwise in the context).
procedure Remove_Context_Clauses (N : Node_Id);
-- Subsidiary of previous one. Remove use_ and with_clauses.
procedure Remove_Limited_With_Clause (N : Node_Id);
-- Remove from visibility the shadow entities introduced for a package
-- mentioned in a limited_with clause. Implements Ada0Y (AI-50217).
procedure Remove_Parents (Lib_Unit : Node_Id);
-- Remove_Parents checks if Lib_Unit is a child spec. If so then the parent
-- contexts established by the corresponding call to Install_Parents are
-- removed. Remove_Parents contains a recursive call to itself to ensure
-- that all parents are removed in the nested case.
procedure Remove_Unit_From_Visibility (Unit_Name : Entity_Id);
-- Reset all visibility flags on unit after compiling it, either as a
-- main unit or as a unit in the context.
procedure Unchain (E : Entity_Id);
-- Remove single entity from visibility list
procedure Analyze_Proper_Body (N : Node_Id; Nam : Entity_Id);
-- Common processing for all stubs (subprograms, tasks, packages, and
-- protected cases). N is the stub to be analyzed. Once the subunit
-- name is established, load and analyze. Nam is the non-overloadable
-- entity for which the proper body provides a completion. Subprogram
-- stubs are handled differently because they can be declarations.
--------------------------
-- Limited_With_Clauses --
--------------------------
-- Limited_With clauses are the mechanism chosen for Ada05 to support
-- mutually recursive types declared in different units. A limited_with
-- clause that names package P in the context of unit U makes the types
-- declared in the visible part of P available within U, but with the
-- restriction that these types can only be used as incomplete types.
-- The limited_with clause does not impose a semantic dependence on P,
-- and it is possible for two packages to have limited_with_clauses on
-- each other without creating an elaboration circularity.
-- To support this feature, the analysis of a limited_with clause must
-- create an abbreviated view of the package, without performing any
-- semantic analysis on it. This "package abstract" contains shadow
-- types that are in one-one correspondence with the real types in the
-- package, and that have the properties of incomplete types.
-- The implementation creates two element lists: one to chain the shadow
-- entities, and one to chain the corresponding type entities in the tree
-- of the package. Links between corresponding entities in both chains
-- allow the compiler to select the proper view of a given type, depending
-- on the context. Note that in contrast with the handling of private
-- types, the limited view and the non-limited view of a type are treated
-- as separate entities, and no entity exchange needs to take place, which
-- makes the implementation must simpler than could be feared.
------------------------------
-- Analyze_Compilation_Unit --
------------------------------
procedure Analyze_Compilation_Unit (N : Node_Id) is
Unit_Node : constant Node_Id := Unit (N);
Lib_Unit : Node_Id := Library_Unit (N);
Spec_Id : Node_Id;
Main_Cunit : constant Node_Id := Cunit (Main_Unit);
Par_Spec_Name : Unit_Name_Type;
Unum : Unit_Number_Type;
procedure Generate_Parent_References (N : Node_Id; P_Id : Entity_Id);
-- Generate cross-reference information for the parents of child units.
-- N is a defining_program_unit_name, and P_Id is the immediate parent.
--------------------------------
-- Generate_Parent_References --
--------------------------------
procedure Generate_Parent_References (N : Node_Id; P_Id : Entity_Id) is
Pref : Node_Id;
P_Name : Entity_Id := P_Id;
begin
Pref := Name (Parent (Defining_Entity (N)));
if Nkind (Pref) = N_Expanded_Name then
-- Done already, if the unit has been compiled indirectly as
-- part of the closure of its context because of inlining.
return;
end if;
while Nkind (Pref) = N_Selected_Component loop
Change_Selected_Component_To_Expanded_Name (Pref);
Set_Entity (Pref, P_Name);
Set_Etype (Pref, Etype (P_Name));
Generate_Reference (P_Name, Pref, 'r');
Pref := Prefix (Pref);
P_Name := Scope (P_Name);
end loop;
-- The guard here on P_Name is to handle the error condition where
-- the parent unit is missing because the file was not found.
if Present (P_Name) then
Set_Entity (Pref, P_Name);
Set_Etype (Pref, Etype (P_Name));
Generate_Reference (P_Name, Pref, 'r');
Style.Check_Identifier (Pref, P_Name);
end if;
end Generate_Parent_References;
-- Start of processing for Analyze_Compilation_Unit
begin
Process_Compilation_Unit_Pragmas (N);
-- If the unit is a subunit whose parent has not been analyzed (which
-- indicates that the main unit is a subunit, either the current one or
-- one of its descendents) then the subunit is compiled as part of the
-- analysis of the parent, which we proceed to do. Basically this gets
-- handled from the top down and we don't want to do anything at this
-- level (i.e. this subunit will be handled on the way down from the
-- parent), so at this level we immediately return. If the subunit
-- ends up not analyzed, it means that the parent did not contain a
-- stub for it, or that there errors were dectected in some ancestor.
if Nkind (Unit_Node) = N_Subunit
and then not Analyzed (Lib_Unit)
then
Semantics (Lib_Unit);
if not Analyzed (Proper_Body (Unit_Node)) then
if Serious_Errors_Detected > 0 then
Error_Msg_N ("subunit not analyzed (errors in parent unit)", N);
else
Error_Msg_N ("missing stub for subunit", N);
end if;
end if;
return;
end if;
-- Analyze context (this will call Sem recursively for with'ed units)
Analyze_Context (N);
-- If the unit is a package body, the spec is already loaded and must
-- be analyzed first, before we analyze the body.
if Nkind (Unit_Node) = N_Package_Body then
-- If no Lib_Unit, then there was a serious previous error, so
-- just ignore the entire analysis effort
if No (Lib_Unit) then
return;
else
Semantics (Lib_Unit);
Check_Unused_Withs (Get_Cunit_Unit_Number (Lib_Unit));
-- Verify that the library unit is a package declaration.
if Nkind (Unit (Lib_Unit)) /= N_Package_Declaration
and then
Nkind (Unit (Lib_Unit)) /= N_Generic_Package_Declaration
then
Error_Msg_N
("no legal package declaration for package body", N);
return;
-- Otherwise, the entity in the declaration is visible. Update
-- the version to reflect dependence of this body on the spec.
else
Spec_Id := Defining_Entity (Unit (Lib_Unit));
Set_Is_Immediately_Visible (Spec_Id, True);
Version_Update (N, Lib_Unit);
if Nkind (Defining_Unit_Name (Unit_Node))
= N_Defining_Program_Unit_Name
then
Generate_Parent_References (Unit_Node, Scope (Spec_Id));
end if;
end if;
end if;
-- If the unit is a subprogram body, then we similarly need to analyze
-- its spec. However, things are a little simpler in this case, because
-- here, this analysis is done only for error checking and consistency
-- purposes, so there's nothing else to be done.
elsif Nkind (Unit_Node) = N_Subprogram_Body then
if Acts_As_Spec (N) then
-- If the subprogram body is a child unit, we must create a
-- declaration for it, in order to properly load the parent(s).
-- After this, the original unit does not acts as a spec, because
-- there is an explicit one. If this unit appears in a context
-- clause, then an implicit with on the parent will be added when
-- installing the context. If this is the main unit, there is no
-- Unit_Table entry for the declaration, (It has the unit number
-- of the main unit) and code generation is unaffected.
Unum := Get_Cunit_Unit_Number (N);
Par_Spec_Name := Get_Parent_Spec_Name (Unit_Name (Unum));
if Par_Spec_Name /= No_Name then
Unum :=
Load_Unit
(Load_Name => Par_Spec_Name,
Required => True,
Subunit => False,
Error_Node => N);
if Unum /= No_Unit then
-- Build subprogram declaration and attach parent unit to it
-- This subprogram declaration does not come from source!
declare
Loc : constant Source_Ptr := Sloc (N);
SCS : constant Boolean :=
Get_Comes_From_Source_Default;
begin
Set_Comes_From_Source_Default (False);
Lib_Unit :=
Make_Compilation_Unit (Loc,
Context_Items => New_Copy_List (Context_Items (N)),
Unit =>
Make_Subprogram_Declaration (Sloc (N),
Specification =>
Copy_Separate_Tree
(Specification (Unit_Node))),
Aux_Decls_Node =>
Make_Compilation_Unit_Aux (Loc));
Set_Library_Unit (N, Lib_Unit);
Set_Parent_Spec (Unit (Lib_Unit), Cunit (Unum));
Semantics (Lib_Unit);
Set_Acts_As_Spec (N, False);
Set_Comes_From_Source_Default (SCS);
end;
end if;
end if;
-- Here for subprogram with separate declaration
else
Semantics (Lib_Unit);
Check_Unused_Withs (Get_Cunit_Unit_Number (Lib_Unit));
Version_Update (N, Lib_Unit);
end if;
if Nkind (Defining_Unit_Name (Specification (Unit_Node))) =
N_Defining_Program_Unit_Name
then
Generate_Parent_References (
Specification (Unit_Node),
Scope (Defining_Entity (Unit (Lib_Unit))));
end if;
end if;
-- If it is a child unit, the parent must be elaborated first
-- and we update version, since we are dependent on our parent.
if Is_Child_Spec (Unit_Node) then
-- The analysis of the parent is done with style checks off
declare
Save_Style_Check : constant Boolean := Style_Check;
Save_C_Restrict : constant Save_Compilation_Unit_Restrictions :=
Compilation_Unit_Restrictions_Save;
begin
if not GNAT_Mode then
Style_Check := False;
end if;
Semantics (Parent_Spec (Unit_Node));
Version_Update (N, Parent_Spec (Unit_Node));
Style_Check := Save_Style_Check;
Compilation_Unit_Restrictions_Restore (Save_C_Restrict);
end;
end if;
-- With the analysis done, install the context. Note that we can't
-- install the context from the with clauses as we analyze them,
-- because each with clause must be analyzed in a clean visibility
-- context, so we have to wait and install them all at once.
Install_Context (N);
if Is_Child_Spec (Unit_Node) then
-- Set the entities of all parents in the program_unit_name.
Generate_Parent_References (
Unit_Node, Get_Parent_Entity (Unit (Parent_Spec (Unit_Node))));
end if;
-- All components of the context: with-clauses, library unit, ancestors
-- if any, (and their context) are analyzed and installed. Now analyze
-- the unit itself, which is either a package, subprogram spec or body.
Analyze (Unit_Node);
-- The above call might have made Unit_Node an N_Subprogram_Body
-- from something else, so propagate any Acts_As_Spec flag.
if Nkind (Unit_Node) = N_Subprogram_Body
and then Acts_As_Spec (Unit_Node)
then
Set_Acts_As_Spec (N);
end if;
-- Treat compilation unit pragmas that appear after the library unit
if Present (Pragmas_After (Aux_Decls_Node (N))) then
declare
Prag_Node : Node_Id := First (Pragmas_After (Aux_Decls_Node (N)));
begin
while Present (Prag_Node) loop
Analyze (Prag_Node);
Next (Prag_Node);
end loop;
end;
end if;
-- Generate distribution stub files if requested and no error
if N = Main_Cunit
and then (Distribution_Stub_Mode = Generate_Receiver_Stub_Body
or else
Distribution_Stub_Mode = Generate_Caller_Stub_Body)
and then not Fatal_Error (Main_Unit)
then
if Is_RCI_Pkg_Spec_Or_Body (N) then
-- Regular RCI package
Add_Stub_Constructs (N);
elsif (Nkind (Unit_Node) = N_Package_Declaration
and then Is_Shared_Passive (Defining_Entity
(Specification (Unit_Node))))
or else (Nkind (Unit_Node) = N_Package_Body
and then
Is_Shared_Passive (Corresponding_Spec (Unit_Node)))
then
-- Shared passive package
Add_Stub_Constructs (N);
elsif Nkind (Unit_Node) = N_Package_Instantiation
and then
Is_Remote_Call_Interface
(Defining_Entity (Specification (Instance_Spec (Unit_Node))))
then
-- Instantiation of a RCI generic package
Add_Stub_Constructs (N);
end if;
-- Reanalyze the unit with the new constructs
Analyze (Unit_Node);
end if;
if Nkind (Unit_Node) = N_Package_Declaration
or else Nkind (Unit_Node) in N_Generic_Declaration
or else Nkind (Unit_Node) = N_Package_Renaming_Declaration
or else Nkind (Unit_Node) = N_Subprogram_Declaration
then
Remove_Unit_From_Visibility (Defining_Entity (Unit_Node));
-- If the unit is an instantiation whose body will be elaborated
-- for inlining purposes, use the the proper entity of the instance.
elsif Nkind (Unit_Node) = N_Package_Instantiation
and then not Error_Posted (Unit_Node)
then
Remove_Unit_From_Visibility
(Defining_Entity (Instance_Spec (Unit_Node)));
elsif Nkind (Unit_Node) = N_Package_Body
or else (Nkind (Unit_Node) = N_Subprogram_Body
and then not Acts_As_Spec (Unit_Node))
then
-- Bodies that are not the main unit are compiled if they
-- are generic or contain generic or inlined units. Their
-- analysis brings in the context of the corresponding spec
-- (unit declaration) which must be removed as well, to
-- return the compilation environment to its proper state.
Remove_Context (Lib_Unit);
Set_Is_Immediately_Visible (Defining_Entity (Unit (Lib_Unit)), False);
end if;
-- Last step is to deinstall the context we just installed
-- as well as the unit just compiled.
Remove_Context (N);
-- If this is the main unit and we are generating code, we must
-- check that all generic units in the context have a body if they
-- need it, even if they have not been instantiated. In the absence
-- of .ali files for generic units, we must force the load of the body,
-- just to produce the proper error if the body is absent. We skip this
-- verification if the main unit itself is generic.
if Get_Cunit_Unit_Number (N) = Main_Unit
and then Operating_Mode = Generate_Code
and then Expander_Active
then
-- Check whether the source for the body of the unit must be
-- included in a standalone library.
Check_Body_Needed_For_SAL (Cunit_Entity (Main_Unit));
-- Indicate that the main unit is now analyzed, to catch possible
-- circularities between it and generic bodies. Remove main unit
-- from visibility. This might seem superfluous, but the main unit
-- must not be visible in the generic body expansions that follow.
Set_Analyzed (N, True);
Set_Is_Immediately_Visible (Cunit_Entity (Main_Unit), False);
declare
Item : Node_Id;
Nam : Entity_Id;
Un : Unit_Number_Type;
Save_Style_Check : constant Boolean := Style_Check;
Save_C_Restrict : constant Save_Compilation_Unit_Restrictions :=
Compilation_Unit_Restrictions_Save;
begin
Item := First (Context_Items (N));
while Present (Item) loop
-- Ada0Y (AI-50217): Do not consider limited-withed units
if Nkind (Item) = N_With_Clause
and then not Implicit_With (Item)
and then not Limited_Present (Item)
then
Nam := Entity (Name (Item));
if (Is_Generic_Subprogram (Nam)
and then not Is_Intrinsic_Subprogram (Nam))
or else (Ekind (Nam) = E_Generic_Package
and then Unit_Requires_Body (Nam))
then
Style_Check := False;
if Present (Renamed_Object (Nam)) then
Un :=
Load_Unit
(Load_Name => Get_Body_Name
(Get_Unit_Name
(Unit_Declaration_Node
(Renamed_Object (Nam)))),
Required => False,
Subunit => False,
Error_Node => N,
Renamings => True);
else
Un :=
Load_Unit
(Load_Name => Get_Body_Name
(Get_Unit_Name (Item)),
Required => False,
Subunit => False,
Error_Node => N,
Renamings => True);
end if;
if Un = No_Unit then
Error_Msg_NE
("body of generic unit& not found", Item, Nam);
exit;
elsif not Analyzed (Cunit (Un))
and then Un /= Main_Unit
and then not Fatal_Error (Un)
then
Style_Check := False;
Semantics (Cunit (Un));
end if;
end if;
end if;
Next (Item);
end loop;
Style_Check := Save_Style_Check;
Compilation_Unit_Restrictions_Restore (Save_C_Restrict);
end;
end if;
-- Deal with creating elaboration Boolean if needed. We create an
-- elaboration boolean only for units that come from source since
-- units manufactured by the compiler never need elab checks.
if Comes_From_Source (N)
and then
(Nkind (Unit (N)) = N_Package_Declaration or else
Nkind (Unit (N)) = N_Generic_Package_Declaration or else
Nkind (Unit (N)) = N_Subprogram_Declaration or else
Nkind (Unit (N)) = N_Generic_Subprogram_Declaration)
then
declare
Loc : constant Source_Ptr := Sloc (N);
Unum : constant Unit_Number_Type := Get_Source_Unit (Loc);
begin
Spec_Id := Defining_Entity (Unit (N));
Generate_Definition (Spec_Id);
-- See if an elaboration entity is required for possible
-- access before elaboration checking. Note that we must
-- allow for this even if -gnatE is not set, since a client
-- may be compiled in -gnatE mode and reference the entity.
-- Case of units which do not require elaboration checks
if
-- Pure units do not need checks
Is_Pure (Spec_Id)
-- Preelaborated units do not need checks
or else Is_Preelaborated (Spec_Id)
-- No checks needed if pagma Elaborate_Body present
or else Has_Pragma_Elaborate_Body (Spec_Id)
-- No checks needed if unit does not require a body
or else not Unit_Requires_Body (Spec_Id)
-- No checks needed for predefined files
or else Is_Predefined_File_Name (Unit_File_Name (Unum))
-- No checks required if no separate spec
or else Acts_As_Spec (N)
then
-- This is a case where we only need the entity for
-- checking to prevent multiple elaboration checks.
Set_Elaboration_Entity_Required (Spec_Id, False);
-- Case of elaboration entity is required for access before
-- elaboration checking (so certainly we must build it!)
else
Set_Elaboration_Entity_Required (Spec_Id, True);
end if;
Build_Elaboration_Entity (N, Spec_Id);
end;
end if;
-- Finally, freeze the compilation unit entity. This for sure is needed
-- because of some warnings that can be output (see Freeze_Subprogram),
-- but may in general be required. If freezing actions result, place
-- them in the compilation unit actions list, and analyze them.
declare
Loc : constant Source_Ptr := Sloc (N);
L : constant List_Id :=
Freeze_Entity (Cunit_Entity (Current_Sem_Unit), Loc);
begin
while Is_Non_Empty_List (L) loop
Insert_Library_Level_Action (Remove_Head (L));
end loop;
end;
Set_Analyzed (N);
if Nkind (Unit_Node) = N_Package_Declaration
and then Get_Cunit_Unit_Number (N) /= Main_Unit
and then Expander_Active
then
declare
Save_Style_Check : constant Boolean := Style_Check;
Save_Warning : constant Warning_Mode_Type := Warning_Mode;
Options : Style_Check_Options;
begin
Save_Style_Check_Options (Options);
Reset_Style_Check_Options;
Opt.Warning_Mode := Suppress;
Check_Body_For_Inlining (N, Defining_Entity (Unit_Node));
Reset_Style_Check_Options;
Set_Style_Check_Options (Options);
Style_Check := Save_Style_Check;
Warning_Mode := Save_Warning;
end;
end if;
end Analyze_Compilation_Unit;
---------------------
-- Analyze_Context --
---------------------
procedure Analyze_Context (N : Node_Id) is
Item : Node_Id;
begin
-- Loop through context items. This is done is three passes:
-- a) The first pass analyze non-limited with-clauses.
-- b) The second pass add implicit limited_with clauses for
-- the parents of child units (Ada0Y: AI-50217)
-- c) The third pass analyzes limited_with clauses (Ada0Y: AI-50217)
Item := First (Context_Items (N));
while Present (Item) loop
-- For with clause, analyze the with clause, and then update
-- the version, since we are dependent on a unit that we with.
if Nkind (Item) = N_With_Clause
and then not Limited_Present (Item)
then
-- Skip analyzing with clause if no unit, nothing to do (this
-- happens for a with that references a non-existant unit)
if Present (Library_Unit (Item)) then
Analyze (Item);
end if;
if not Implicit_With (Item) then
Version_Update (N, Library_Unit (Item));
end if;
-- But skip use clauses at this stage, since we don't want to do
-- any installing of potentially use visible entities until we
-- we actually install the complete context (in Install_Context).
-- Otherwise things can get installed in the wrong context.
-- Similarly, pragmas are analyzed in Install_Context, after all
-- the implicit with's on parent units are generated.
else
null;
end if;
Next (Item);
end loop;
-- Second pass: add implicit limited_with_clauses for parents of
-- child units mentioned in limited_with clauses.
Item := First (Context_Items (N));
while Present (Item) loop
if Nkind (Item) = N_With_Clause
and then Limited_Present (Item)
and then Nkind (Name (Item)) = N_Selected_Component
then
Expand_Limited_With_Clause
(Nam => Prefix (Name (Item)), N => Item);
end if;
Next (Item);
end loop;
-- Third pass: examine all limited_with clauses.
Item := First (Context_Items (N));
while Present (Item) loop
if Nkind (Item) = N_With_Clause
and then Limited_Present (Item)
then
if Nkind (Unit (N)) /= N_Package_Declaration then
Error_Msg_N ("limited with_clause only allowed in"
& " package specification", Item);
end if;
-- Skip analyzing with clause if no unit, see above.
if Present (Library_Unit (Item)) then
Analyze (Item);
end if;
-- A limited_with does not impose an elaboration order, but
-- there is a semantic dependency for recompilation purposes.
if not Implicit_With (Item) then
Version_Update (N, Library_Unit (Item));
end if;
end if;
Next (Item);
end loop;
end Analyze_Context;
-------------------------------
-- Analyze_Package_Body_Stub --
-------------------------------
procedure Analyze_Package_Body_Stub (N : Node_Id) is
Id : constant Entity_Id := Defining_Identifier (N);
Nam : Entity_Id;
begin
-- The package declaration must be in the current declarative part.
Check_Stub_Level (N);
Nam := Current_Entity_In_Scope (Id);
if No (Nam) or else not Is_Package (Nam) then
Error_Msg_N ("missing specification for package stub", N);
elsif Has_Completion (Nam)
and then Present (Corresponding_Body (Unit_Declaration_Node (Nam)))
then
Error_Msg_N ("duplicate or redundant stub for package", N);
else
-- Indicate that the body of the package exists. If we are doing
-- only semantic analysis, the stub stands for the body. If we are
-- generating code, the existence of the body will be confirmed
-- when we load the proper body.
Set_Has_Completion (Nam);
Set_Scope (Defining_Entity (N), Current_Scope);
Generate_Reference (Nam, Id, 'b');
Analyze_Proper_Body (N, Nam);
end if;
end Analyze_Package_Body_Stub;
-------------------------
-- Analyze_Proper_Body --
-------------------------
procedure Analyze_Proper_Body (N : Node_Id; Nam : Entity_Id) is
Subunit_Name : constant Unit_Name_Type := Get_Unit_Name (N);
Unum : Unit_Number_Type;
procedure Optional_Subunit;
-- This procedure is called when the main unit is a stub, or when we
-- are not generating code. In such a case, we analyze the subunit if
-- present, which is user-friendly and in fact required for ASIS, but
-- we don't complain if the subunit is missing.
----------------------
-- Optional_Subunit --
----------------------
procedure Optional_Subunit is
Comp_Unit : Node_Id;
begin
-- Try to load subunit, but ignore any errors that occur during
-- the loading of the subunit, by using the special feature in
-- Errout to ignore all errors. Note that Fatal_Error will still
-- be set, so we will be able to check for this case below.
Ignore_Errors_Enable := Ignore_Errors_Enable + 1;
Unum :=
Load_Unit
(Load_Name => Subunit_Name,
Required => False,
Subunit => True,
Error_Node => N);
Ignore_Errors_Enable := Ignore_Errors_Enable - 1;
-- All done if we successfully loaded the subunit
if Unum /= No_Unit
and then (not Fatal_Error (Unum) or else Try_Semantics)
then
Comp_Unit := Cunit (Unum);
Set_Corresponding_Stub (Unit (Comp_Unit), N);
Analyze_Subunit (Comp_Unit);
Set_Library_Unit (N, Comp_Unit);
elsif Unum = No_Unit
and then Present (Nam)
then
if Is_Protected_Type (Nam) then
Set_Corresponding_Body (Parent (Nam), Defining_Identifier (N));
else
Set_Corresponding_Body (
Unit_Declaration_Node (Nam), Defining_Identifier (N));
end if;
end if;
end Optional_Subunit;
-- Start of processing for Analyze_Proper_Body
begin
-- If the subunit is already loaded, it means that the main unit
-- is a subunit, and that the current unit is one of its parents
-- which was being analyzed to provide the needed context for the
-- analysis of the subunit. In this case we analyze the subunit and
-- continue with the parent, without looking a subsequent subunits.
if Is_Loaded (Subunit_Name) then
-- If the proper body is already linked to the stub node,
-- the stub is in a generic unit and just needs analyzing.
if Present (Library_Unit (N)) then
Set_Corresponding_Stub (Unit (Library_Unit (N)), N);
Analyze_Subunit (Library_Unit (N));
-- Otherwise we must load the subunit and link to it
else
-- Load the subunit, this must work, since we originally
-- loaded the subunit earlier on. So this will not really
-- load it, just give access to it.
Unum :=
Load_Unit
(Load_Name => Subunit_Name,
Required => True,
Subunit => False,
Error_Node => N);
-- And analyze the subunit in the parent context (note that we
-- do not call Semantics, since that would remove the parent
-- context). Because of this, we have to manually reset the
-- compiler state to Analyzing since it got destroyed by Load.
if Unum /= No_Unit then
Compiler_State := Analyzing;
-- Check that the proper body is a subunit and not a child
-- unit. If the unit was previously loaded, the error will
-- have been emitted when copying the generic node, so we
-- just return to avoid cascaded errors.
if Nkind (Unit (Cunit (Unum))) /= N_Subunit then
return;
end if;
Set_Corresponding_Stub (Unit (Cunit (Unum)), N);
Analyze_Subunit (Cunit (Unum));
Set_Library_Unit (N, Cunit (Unum));
end if;
end if;
-- If the main unit is a subunit, then we are just performing semantic
-- analysis on that subunit, and any other subunits of any parent unit
-- should be ignored, except that if we are building trees for ASIS
-- usage we want to annotate the stub properly.
elsif Nkind (Unit (Cunit (Main_Unit))) = N_Subunit
and then Subunit_Name /= Unit_Name (Main_Unit)
then
if ASIS_Mode then
Optional_Subunit;
end if;
-- But before we return, set the flag for unloaded subunits. This
-- will suppress junk warnings of variables in the same declarative
-- part (or a higher level one) that are in danger of looking unused
-- when in fact there might be a declaration in the subunit that we
-- do not intend to load.
Unloaded_Subunits := True;
return;
-- If the subunit is not already loaded, and we are generating code,
-- then this is the case where compilation started from the parent,
-- and we are generating code for an entire subunit tree. In that
-- case we definitely need to load the subunit.
-- In order to continue the analysis with the rest of the parent,
-- and other subunits, we load the unit without requiring its
-- presence, and emit a warning if not found, rather than terminating
-- the compilation abruptly, as for other missing file problems.
elsif Original_Operating_Mode = Generate_Code then
-- If the proper body is already linked to the stub node,
-- the stub is in a generic unit and just needs analyzing.
-- We update the version. Although we are not technically
-- semantically dependent on the subunit, given our approach
-- of macro substitution of subunits, it makes sense to
-- include it in the version identification.
if Present (Library_Unit (N)) then
Set_Corresponding_Stub (Unit (Library_Unit (N)), N);
Analyze_Subunit (Library_Unit (N));
Version_Update (Cunit (Main_Unit), Library_Unit (N));
-- Otherwise we must load the subunit and link to it
else
Unum :=
Load_Unit
(Load_Name => Subunit_Name,
Required => False,
Subunit => True,
Error_Node => N);
if Original_Operating_Mode = Generate_Code
and then Unum = No_Unit
then
Error_Msg_Name_1 := Subunit_Name;
Error_Msg_Name_2 :=
Get_File_Name (Subunit_Name, Subunit => True);
Error_Msg_N
("subunit% in file{ not found!?", N);
Subunits_Missing := True;
end if;
-- Load_Unit may reset Compiler_State, since it may have been
-- necessary to parse an additional units, so we make sure
-- that we reset it to the Analyzing state.
Compiler_State := Analyzing;
if Unum /= No_Unit
and then (not Fatal_Error (Unum) or else Try_Semantics)
then
if Debug_Flag_L then
Write_Str ("*** Loaded subunit from stub. Analyze");
Write_Eol;
end if;
declare
Comp_Unit : constant Node_Id := Cunit (Unum);
begin
-- Check for child unit instead of subunit
if Nkind (Unit (Comp_Unit)) /= N_Subunit then
Error_Msg_N
("expected SEPARATE subunit, found child unit",
Cunit_Entity (Unum));
-- OK, we have a subunit, so go ahead and analyze it,
-- and set Scope of entity in stub, for ASIS use.
else
Set_Corresponding_Stub (Unit (Comp_Unit), N);
Analyze_Subunit (Comp_Unit);
Set_Library_Unit (N, Comp_Unit);
-- We update the version. Although we are not technically
-- semantically dependent on the subunit, given our
-- approach of macro substitution of subunits, it makes
-- sense to include it in the version identification.
Version_Update (Cunit (Main_Unit), Comp_Unit);
end if;
end;
end if;
end if;
-- The remaining case is when the subunit is not already loaded and
-- we are not generating code. In this case we are just performing
-- semantic analysis on the parent, and we are not interested in
-- the subunit. For subprograms, analyze the stub as a body. For
-- other entities the stub has already been marked as completed.
else
Optional_Subunit;
end if;
end Analyze_Proper_Body;
----------------------------------
-- Analyze_Protected_Body_Stub --
----------------------------------
procedure Analyze_Protected_Body_Stub (N : Node_Id) is
Nam : Entity_Id := Current_Entity_In_Scope (Defining_Identifier (N));
begin
Check_Stub_Level (N);
-- First occurence of name may have been as an incomplete type.
if Present (Nam) and then Ekind (Nam) = E_Incomplete_Type then
Nam := Full_View (Nam);
end if;
if No (Nam)
or else not Is_Protected_Type (Etype (Nam))
then
Error_Msg_N ("missing specification for Protected body", N);
else
Set_Scope (Defining_Entity (N), Current_Scope);
Set_Has_Completion (Etype (Nam));
Generate_Reference (Nam, Defining_Identifier (N), 'b');
Analyze_Proper_Body (N, Etype (Nam));
end if;
end Analyze_Protected_Body_Stub;
----------------------------------
-- Analyze_Subprogram_Body_Stub --
----------------------------------
-- A subprogram body stub can appear with or without a previous
-- specification. If there is one, the analysis of the body will
-- find it and verify conformance. The formals appearing in the
-- specification of the stub play no role, except for requiring an
-- additional conformance check. If there is no previous subprogram
-- declaration, the stub acts as a spec, and provides the defining
-- entity for the subprogram.
procedure Analyze_Subprogram_Body_Stub (N : Node_Id) is
Decl : Node_Id;
begin
Check_Stub_Level (N);
-- Verify that the identifier for the stub is unique within this
-- declarative part.
if Nkind (Parent (N)) = N_Block_Statement
or else Nkind (Parent (N)) = N_Package_Body
or else Nkind (Parent (N)) = N_Subprogram_Body
then
Decl := First (Declarations (Parent (N)));
while Present (Decl)
and then Decl /= N
loop
if Nkind (Decl) = N_Subprogram_Body_Stub
and then (Chars (Defining_Unit_Name (Specification (Decl)))
= Chars (Defining_Unit_Name (Specification (N))))
then
Error_Msg_N ("identifier for stub is not unique", N);
end if;
Next (Decl);
end loop;
end if;
-- Treat stub as a body, which checks conformance if there is a previous
-- declaration, or else introduces entity and its signature.
Analyze_Subprogram_Body (N);
Analyze_Proper_Body (N, Empty);
end Analyze_Subprogram_Body_Stub;
---------------------
-- Analyze_Subunit --
---------------------
-- A subunit is compiled either by itself (for semantic checking)
-- or as part of compiling the parent (for code generation). In
-- either case, by the time we actually process the subunit, the
-- parent has already been installed and analyzed. The node N is
-- a compilation unit, whose context needs to be treated here,
-- because we come directly here from the parent without calling
-- Analyze_Compilation_Unit.
-- The compilation context includes the explicit context of the
-- subunit, and the context of the parent, together with the parent
-- itself. In order to compile the current context, we remove the
-- one inherited from the parent, in order to have a clean visibility
-- table. We restore the parent context before analyzing the proper
-- body itself. On exit, we remove only the explicit context of the
-- subunit.
procedure Analyze_Subunit (N : Node_Id) is
Lib_Unit : constant Node_Id := Library_Unit (N);
Par_Unit : constant Entity_Id := Current_Scope;
Lib_Spec : Node_Id := Library_Unit (Lib_Unit);
Num_Scopes : Int := 0;
Use_Clauses : array (1 .. Scope_Stack.Last) of Node_Id;
Enclosing_Child : Entity_Id := Empty;
Svg : constant Suppress_Array := Scope_Suppress;
procedure Analyze_Subunit_Context;
-- Capture names in use clauses of the subunit. This must be done
-- before re-installing parent declarations, because items in the
-- context must not be hidden by declarations local to the parent.
procedure Re_Install_Parents (L : Node_Id; Scop : Entity_Id);
-- Recursive procedure to restore scope of all ancestors of subunit,
-- from outermost in. If parent is not a subunit, the call to install
-- context installs context of spec and (if parent is a child unit)
-- the context of its parents as well. It is confusing that parents
-- should be treated differently in both cases, but the semantics are
-- just not identical.
procedure Re_Install_Use_Clauses;
-- As part of the removal of the parent scope, the use clauses are
-- removed, to be reinstalled when the context of the subunit has
-- been analyzed. Use clauses may also have been affected by the
-- analysis of the context of the subunit, so they have to be applied
-- again, to insure that the compilation environment of the rest of
-- the parent unit is identical.
procedure Remove_Scope;
-- Remove current scope from scope stack, and preserve the list
-- of use clauses in it, to be reinstalled after context is analyzed.
------------------------------
-- Analyze_Subunit_Context --
------------------------------
procedure Analyze_Subunit_Context is
Item : Node_Id;
Nam : Node_Id;
Unit_Name : Entity_Id;
begin
Analyze_Context (N);
Item := First (Context_Items (N));
-- make withed units immediately visible. If child unit, make the
-- ultimate parent immediately visible.
while Present (Item) loop
if Nkind (Item) = N_With_Clause then
Unit_Name := Entity (Name (Item));
while Is_Child_Unit (Unit_Name) loop
Set_Is_Visible_Child_Unit (Unit_Name);
Unit_Name := Scope (Unit_Name);
end loop;
if not Is_Immediately_Visible (Unit_Name) then
Set_Is_Immediately_Visible (Unit_Name);
Set_Context_Installed (Item);
end if;
elsif Nkind (Item) = N_Use_Package_Clause then
Nam := First (Names (Item));
while Present (Nam) loop
Analyze (Nam);
Next (Nam);
end loop;
elsif Nkind (Item) = N_Use_Type_Clause then
Nam := First (Subtype_Marks (Item));
while Present (Nam) loop
Analyze (Nam);
Next (Nam);
end loop;
end if;
Next (Item);
end loop;
Item := First (Context_Items (N));
-- reset visibility of withed units. They will be made visible
-- again when we install the subunit context.
while Present (Item) loop
if Nkind (Item) = N_With_Clause then
Unit_Name := Entity (Name (Item));
while Is_Child_Unit (Unit_Name) loop
Set_Is_Visible_Child_Unit (Unit_Name, False);
Unit_Name := Scope (Unit_Name);
end loop;
if Context_Installed (Item) then
Set_Is_Immediately_Visible (Unit_Name, False);
Set_Context_Installed (Item, False);
end if;
end if;
Next (Item);
end loop;
end Analyze_Subunit_Context;
------------------------
-- Re_Install_Parents --
------------------------
procedure Re_Install_Parents (L : Node_Id; Scop : Entity_Id) is
E : Entity_Id;
begin
if Nkind (Unit (L)) = N_Subunit then
Re_Install_Parents (Library_Unit (L), Scope (Scop));
end if;
Install_Context (L);
-- If the subunit occurs within a child unit, we must restore the
-- immediate visibility of any siblings that may occur in context.
if Present (Enclosing_Child) then
Install_Siblings (Enclosing_Child, L);
end if;
New_Scope (Scop);
if Scop /= Par_Unit then
Set_Is_Immediately_Visible (Scop);
end if;
E := First_Entity (Current_Scope);
while Present (E) loop
Set_Is_Immediately_Visible (E);
Next_Entity (E);
end loop;
-- A subunit appears within a body, and for a nested subunits
-- all the parents are bodies. Restore full visibility of their
-- private entities.
if Ekind (Scop) = E_Package then
Set_In_Package_Body (Scop);
Install_Private_Declarations (Scop);
end if;
end Re_Install_Parents;
----------------------------
-- Re_Install_Use_Clauses --
----------------------------
procedure Re_Install_Use_Clauses is
U : Node_Id;
begin
for J in reverse 1 .. Num_Scopes loop
U := Use_Clauses (J);
Scope_Stack.Table (Scope_Stack.Last - J + 1).First_Use_Clause := U;
Install_Use_Clauses (U);
end loop;
end Re_Install_Use_Clauses;
------------------
-- Remove_Scope --
------------------
procedure Remove_Scope is
E : Entity_Id;
begin
Num_Scopes := Num_Scopes + 1;
Use_Clauses (Num_Scopes) :=
Scope_Stack.Table (Scope_Stack.Last).First_Use_Clause;
E := First_Entity (Current_Scope);
while Present (E) loop
Set_Is_Immediately_Visible (E, False);
Next_Entity (E);
end loop;
if Is_Child_Unit (Current_Scope) then
Enclosing_Child := Current_Scope;
end if;
Pop_Scope;
end Remove_Scope;
-- Start of processing for Analyze_Subunit
begin
if not Is_Empty_List (Context_Items (N)) then
-- Save current use clauses.
Remove_Scope;
Remove_Context (Lib_Unit);
-- Now remove parents and their context, including enclosing
-- subunits and the outer parent body which is not a subunit.
if Present (Lib_Spec) then
Remove_Context (Lib_Spec);
while Nkind (Unit (Lib_Spec)) = N_Subunit loop
Lib_Spec := Library_Unit (Lib_Spec);
Remove_Scope;
Remove_Context (Lib_Spec);
end loop;
if Nkind (Unit (Lib_Unit)) = N_Subunit then
Remove_Scope;
end if;
if Nkind (Unit (Lib_Spec)) = N_Package_Body then
Remove_Context (Library_Unit (Lib_Spec));
end if;
end if;
Analyze_Subunit_Context;
Re_Install_Parents (Lib_Unit, Par_Unit);
-- If the context includes a child unit of the parent of the
-- subunit, the parent will have been removed from visibility,
-- after compiling that cousin in the context. The visibility
-- of the parent must be restored now. This also applies if the
-- context includes another subunit of the same parent which in
-- turn includes a child unit in its context.
if Ekind (Par_Unit) = E_Package then
if not Is_Immediately_Visible (Par_Unit)
or else (Present (First_Entity (Par_Unit))
and then not Is_Immediately_Visible
(First_Entity (Par_Unit)))
then
Set_Is_Immediately_Visible (Par_Unit);
Install_Visible_Declarations (Par_Unit);
Install_Private_Declarations (Par_Unit);
end if;
end if;
Re_Install_Use_Clauses;
Install_Context (N);
-- Restore state of suppress flags for current body.
Scope_Suppress := Svg;
-- If the subunit is within a child unit, then siblings of any
-- parent unit that appear in the context clause of the subunit
-- must also be made immediately visible.
if Present (Enclosing_Child) then
Install_Siblings (Enclosing_Child, N);
end if;
end if;
Analyze (Proper_Body (Unit (N)));
Remove_Context (N);
end Analyze_Subunit;
----------------------------
-- Analyze_Task_Body_Stub --
----------------------------
procedure Analyze_Task_Body_Stub (N : Node_Id) is
Nam : Entity_Id := Current_Entity_In_Scope (Defining_Identifier (N));
Loc : constant Source_Ptr := Sloc (N);
begin
Check_Stub_Level (N);
-- First occurence of name may have been as an incomplete type.
if Present (Nam) and then Ekind (Nam) = E_Incomplete_Type then
Nam := Full_View (Nam);
end if;
if No (Nam)
or else not Is_Task_Type (Etype (Nam))
then
Error_Msg_N ("missing specification for task body", N);
else
Set_Scope (Defining_Entity (N), Current_Scope);
Generate_Reference (Nam, Defining_Identifier (N), 'b');
Set_Has_Completion (Etype (Nam));
Analyze_Proper_Body (N, Etype (Nam));
-- Set elaboration flag to indicate that entity is callable.
-- This cannot be done in the expansion of the body itself,
-- because the proper body is not in a declarative part. This
-- is only done if expansion is active, because the context
-- may be generic and the flag not defined yet.
if Expander_Active then
Insert_After (N,
Make_Assignment_Statement (Loc,
Name =>
Make_Identifier (Loc,
New_External_Name (Chars (Etype (Nam)), 'E')),
Expression => New_Reference_To (Standard_True, Loc)));
end if;
end if;
end Analyze_Task_Body_Stub;
-------------------------
-- Analyze_With_Clause --
-------------------------
-- Analyze the declaration of a unit in a with clause. At end,
-- label the with clause with the defining entity for the unit.
procedure Analyze_With_Clause (N : Node_Id) is
-- Retrieve the original kind of the unit node, before analysis.
-- If it is a subprogram instantiation, its analysis below will
-- rewrite as the declaration of the wrapper package. If the same
-- instantiation appears indirectly elsewhere in the context, it
-- will have been analyzed already.
Unit_Kind : constant Node_Kind :=
Nkind (Original_Node (Unit (Library_Unit (N))));
E_Name : Entity_Id;
Par_Name : Entity_Id;
Pref : Node_Id;
U : Node_Id;
Intunit : Boolean;
-- Set True if the unit currently being compiled is an internal unit
Save_Style_Check : constant Boolean := Opt.Style_Check;
Save_C_Restrict : constant Save_Compilation_Unit_Restrictions :=
Compilation_Unit_Restrictions_Save;
begin
if Limited_Present (N) then
-- Ada0Y (AI-50217): Build visibility structures but do not
-- analyze unit
Build_Limited_Views (N);
return;
end if;
-- We reset ordinary style checking during the analysis of a with'ed
-- unit, but we do NOT reset GNAT special analysis mode (the latter
-- definitely *does* apply to with'ed units).
if not GNAT_Mode then
Style_Check := False;
end if;
-- If the library unit is a predefined unit, and we are in high
-- integrity mode, then temporarily reset Configurable_Run_Time_Mode
-- for the analysis of the with'ed unit. This mode does not prevent
-- explicit with'ing of run-time units.
if Configurable_Run_Time_Mode
and then
Is_Predefined_File_Name
(Unit_File_Name (Get_Source_Unit (Unit (Library_Unit (N)))))
then
Configurable_Run_Time_Mode := False;
Semantics (Library_Unit (N));
Configurable_Run_Time_Mode := True;
else
Semantics (Library_Unit (N));
end if;
U := Unit (Library_Unit (N));
Intunit := Is_Internal_File_Name (Unit_File_Name (Current_Sem_Unit));
-- Following checks are skipped for dummy packages (those supplied
-- for with's where no matching file could be found). Such packages
-- are identified by the Sloc value being set to No_Location
if Sloc (U) /= No_Location then
-- Check restrictions, except that we skip the check if this
-- is an internal unit unless we are compiling the internal
-- unit as the main unit. We also skip this for dummy packages.
if not Intunit or else Current_Sem_Unit = Main_Unit then
Check_Restricted_Unit (Unit_Name (Get_Source_Unit (U)), N);
end if;
-- Check for inappropriate with of internal implementation unit
-- if we are currently compiling the main unit and the main unit
-- is itself not an internal unit. We do not issue this message
-- for implicit with's generated by the compiler itself.
if Implementation_Unit_Warnings
and then Current_Sem_Unit = Main_Unit
and then Implementation_Unit (Get_Source_Unit (U))
and then not Intunit
and then not Implicit_With (N)
then
Error_Msg_N ("& is an internal 'G'N'A'T unit?", Name (N));
Error_Msg_N
("\use of this unit is non-portable and version-dependent?",
Name (N));
end if;
end if;
-- Semantic analysis of a generic unit is performed on a copy of
-- the original tree. Retrieve the entity on which semantic info
-- actually appears.
if Unit_Kind in N_Generic_Declaration then
E_Name := Defining_Entity (U);
-- Note: in the following test, Unit_Kind is the original Nkind, but
-- in the case of an instantiation, semantic analysis above will
-- have replaced the unit by its instantiated version. If the instance
-- body has been generated, the instance now denotes the body entity.
-- For visibility purposes we need the entity of its spec.
elsif (Unit_Kind = N_Package_Instantiation
or else Nkind (Original_Node (Unit (Library_Unit (N)))) =
N_Package_Instantiation)
and then Nkind (U) = N_Package_Body
then
E_Name := Corresponding_Spec (U);
elsif Unit_Kind = N_Package_Instantiation
and then Nkind (U) = N_Package_Instantiation
then
-- If the instance has not been rewritten as a package declaration,
-- then it appeared already in a previous with clause. Retrieve
-- the entity from the previous instance.
E_Name := Defining_Entity (Specification (Instance_Spec (U)));
elsif Unit_Kind = N_Procedure_Instantiation
or else Unit_Kind = N_Function_Instantiation
then
-- Instantiation node is replaced with a package that contains
-- renaming declarations and instance itself. The subprogram
-- Instance is declared in the visible part of the wrapper package.
E_Name := First_Entity (Defining_Entity (U));
while Present (E_Name) loop
exit when Is_Subprogram (E_Name)
and then Is_Generic_Instance (E_Name);
E_Name := Next_Entity (E_Name);
end loop;
elsif Unit_Kind = N_Package_Renaming_Declaration
or else Unit_Kind in N_Generic_Renaming_Declaration
then
E_Name := Defining_Entity (U);
elsif Unit_Kind = N_Subprogram_Body
and then Nkind (Name (N)) = N_Selected_Component
and then not Acts_As_Spec (Library_Unit (N))
then
-- For a child unit that has no spec, one has been created and
-- analyzed. The entity required is that of the spec.
E_Name := Corresponding_Spec (U);
else
E_Name := Defining_Entity (U);
end if;
if Nkind (Name (N)) = N_Selected_Component then
-- Child unit in a with clause
Change_Selected_Component_To_Expanded_Name (Name (N));
end if;
-- Restore style checks and restrictions
Style_Check := Save_Style_Check;
Compilation_Unit_Restrictions_Restore (Save_C_Restrict);
-- Record the reference, but do NOT set the unit as referenced, we
-- want to consider the unit as unreferenced if this is the only
-- reference that occurs.
Set_Entity_With_Style_Check (Name (N), E_Name);
Generate_Reference (E_Name, Name (N), 'w', Set_Ref => False);
if Is_Child_Unit (E_Name) then
Pref := Prefix (Name (N));
Par_Name := Scope (E_Name);
while Nkind (Pref) = N_Selected_Component loop
Change_Selected_Component_To_Expanded_Name (Pref);
Set_Entity_With_Style_Check (Pref, Par_Name);
Generate_Reference (Par_Name, Pref);
Pref := Prefix (Pref);
-- If E_Name is the dummy entity for a nonexistent unit,
-- its scope is set to Standard_Standard, and no attempt
-- should be made to further unwind scopes.
if Par_Name /= Standard_Standard then
Par_Name := Scope (Par_Name);
end if;
end loop;
if Present (Entity (Pref))
and then not Analyzed (Parent (Parent (Entity (Pref))))
then
-- If the entity is set without its unit being compiled,
-- the original parent is a renaming, and Par_Name is the
-- renamed entity. For visibility purposes, we need the
-- original entity, which must be analyzed now, because
-- Load_Unit retrieves directly the renamed unit, and the
-- renaming declaration itself has not been analyzed.
Analyze (Parent (Parent (Entity (Pref))));
pragma Assert (Renamed_Object (Entity (Pref)) = Par_Name);
Par_Name := Entity (Pref);
end if;
Set_Entity_With_Style_Check (Pref, Par_Name);
Generate_Reference (Par_Name, Pref);
end if;
-- If the withed unit is System, and a system extension pragma is
-- present, compile the extension now, rather than waiting for
-- a visibility check on a specific entity.
if Chars (E_Name) = Name_System
and then Scope (E_Name) = Standard_Standard
and then Present (System_Extend_Unit)
and then Present_System_Aux (N)
then
-- If the extension is not present, an error will have been emitted.
null;
end if;
end Analyze_With_Clause;
------------------------------
-- Analyze_With_Type_Clause --
------------------------------
procedure Analyze_With_Type_Clause (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Nam : constant Node_Id := Name (N);
Pack : Node_Id;
Decl : Node_Id;
P : Entity_Id;
Unum : Unit_Number_Type;
Sel : Node_Id;
procedure Decorate_Tagged_Type (T : Entity_Id);
-- Set basic attributes of type, including its class_wide type.
function In_Chain (E : Entity_Id) return Boolean;
-- Check that the imported type is not already in the homonym chain,
-- for example through a with_type clause in a parent unit.
--------------------------
-- Decorate_Tagged_Type --
--------------------------
procedure Decorate_Tagged_Type (T : Entity_Id) is
CW : Entity_Id;
begin
Set_Ekind (T, E_Record_Type);
Set_Is_Tagged_Type (T);
Set_Etype (T, T);
Set_From_With_Type (T);
Set_Scope (T, P);
if not In_Chain (T) then
Set_Homonym (T, Current_Entity (T));
Set_Current_Entity (T);
end if;
-- Build bogus class_wide type, if not previously done.
if No (Class_Wide_Type (T)) then
CW := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
Set_Ekind (CW, E_Class_Wide_Type);
Set_Etype (CW, T);
Set_Scope (CW, P);
Set_Is_Tagged_Type (CW);
Set_Is_First_Subtype (CW, True);
Init_Size_Align (CW);
Set_Has_Unknown_Discriminants
(CW, True);
Set_Class_Wide_Type (CW, CW);
Set_Equivalent_Type (CW, Empty);
Set_From_With_Type (CW);
Set_Class_Wide_Type (T, CW);
end if;
end Decorate_Tagged_Type;
--------------
-- In_Chain --
--------------
function In_Chain (E : Entity_Id) return Boolean is
H : Entity_Id := Current_Entity (E);
begin
while Present (H) loop
if H = E then
return True;
else
H := Homonym (H);
end if;
end loop;
return False;
end In_Chain;
-- Start of processing for Analyze_With_Type_Clause
begin
if Nkind (Nam) = N_Selected_Component then
Pack := New_Copy_Tree (Prefix (Nam));
Sel := Selector_Name (Nam);
else
Error_Msg_N ("illegal name for imported type", Nam);
return;
end if;
Decl :=
Make_Package_Declaration (Loc,
Specification =>
(Make_Package_Specification (Loc,
Defining_Unit_Name => Pack,
Visible_Declarations => New_List,
End_Label => Empty)));
Unum :=
Load_Unit
(Load_Name => Get_Unit_Name (Decl),
Required => True,
Subunit => False,
Error_Node => Nam);
if Unum = No_Unit
or else Nkind (Unit (Cunit (Unum))) /= N_Package_Declaration
then
Error_Msg_N ("imported type must be declared in package", Nam);
return;
elsif Unum = Current_Sem_Unit then
-- If type is defined in unit being analyzed, then the clause
-- is redundant.
return;
else
P := Cunit_Entity (Unum);
end if;
-- Find declaration for imported type, and set its basic attributes
-- if it has not been analyzed (which will be the case if there is
-- circular dependence).
declare
Decl : Node_Id;
Typ : Entity_Id;
begin
if not Analyzed (Cunit (Unum))
and then not From_With_Type (P)
then
Set_Ekind (P, E_Package);
Set_Etype (P, Standard_Void_Type);
Set_From_With_Type (P);
Set_Scope (P, Standard_Standard);
Set_Homonym (P, Current_Entity (P));
Set_Current_Entity (P);
elsif Analyzed (Cunit (Unum))
and then Is_Child_Unit (P)
then
-- If the child unit is already in scope, indicate that it is
-- visible, and remains so after intervening calls to rtsfind.
Set_Is_Visible_Child_Unit (P);
end if;
if Nkind (Parent (P)) = N_Defining_Program_Unit_Name then
-- Make parent packages visible.
declare
Parent_Comp : Node_Id;
Parent_Id : Entity_Id;
Child : Entity_Id;
begin
Child := P;
Parent_Comp := Parent_Spec (Unit (Cunit (Unum)));
loop
Parent_Id := Defining_Entity (Unit (Parent_Comp));
Set_Scope (Child, Parent_Id);
-- The type may be imported from a child unit, in which
-- case the current compilation appears in the name. Do
-- not change its visibility here because it will conflict
-- with the subsequent normal processing.
if not Analyzed (Unit_Declaration_Node (Parent_Id))
and then Parent_Id /= Cunit_Entity (Current_Sem_Unit)
then
Set_Ekind (Parent_Id, E_Package);
Set_Etype (Parent_Id, Standard_Void_Type);
-- The same package may appear is several with_type
-- clauses.
if not From_With_Type (Parent_Id) then
Set_Homonym (Parent_Id, Current_Entity (Parent_Id));
Set_Current_Entity (Parent_Id);
Set_From_With_Type (Parent_Id);
end if;
end if;
Set_Is_Immediately_Visible (Parent_Id);
Child := Parent_Id;
Parent_Comp := Parent_Spec (Unit (Parent_Comp));
exit when No (Parent_Comp);
end loop;
Set_Scope (Parent_Id, Standard_Standard);
end;
end if;
-- Even if analyzed, the package may not be currently visible. It
-- must be while the with_type clause is active.
Set_Is_Immediately_Visible (P);
Decl :=
First (Visible_Declarations (Specification (Unit (Cunit (Unum)))));
while Present (Decl) loop
if Nkind (Decl) = N_Full_Type_Declaration
and then Chars (Defining_Identifier (Decl)) = Chars (Sel)
then
Typ := Defining_Identifier (Decl);
if Tagged_Present (N) then
-- The declaration must indicate that this is a tagged
-- type or a type extension.
if (Nkind (Type_Definition (Decl)) = N_Record_Definition
and then Tagged_Present (Type_Definition (Decl)))
or else
(Nkind (Type_Definition (Decl))
= N_Derived_Type_Definition
and then Present
(Record_Extension_Part (Type_Definition (Decl))))
then
null;
else
Error_Msg_N ("imported type is not a tagged type", Nam);
return;
end if;
if not Analyzed (Decl) then
-- Unit is not currently visible. Add basic attributes
-- to type and build its class-wide type.
Init_Size_Align (Typ);
Decorate_Tagged_Type (Typ);
end if;
else
if Nkind (Type_Definition (Decl))
/= N_Access_To_Object_Definition
then
Error_Msg_N
("imported type is not an access type", Nam);
elsif not Analyzed (Decl) then
Set_Ekind (Typ, E_Access_Type);
Set_Etype (Typ, Typ);
Set_Scope (Typ, P);
Init_Size (Typ, System_Address_Size);
Init_Alignment (Typ);
Set_Directly_Designated_Type (Typ, Standard_Integer);
Set_From_With_Type (Typ);
if not In_Chain (Typ) then
Set_Homonym (Typ, Current_Entity (Typ));
Set_Current_Entity (Typ);
end if;
end if;
end if;
Set_Entity (Sel, Typ);
return;
elsif ((Nkind (Decl) = N_Private_Type_Declaration
and then Tagged_Present (Decl))
or else (Nkind (Decl) = N_Private_Extension_Declaration))
and then Chars (Defining_Identifier (Decl)) = Chars (Sel)
then
Typ := Defining_Identifier (Decl);
if not Tagged_Present (N) then
Error_Msg_N ("type must be declared tagged", N);
elsif not Analyzed (Decl) then
Decorate_Tagged_Type (Typ);
end if;
Set_Entity (Sel, Typ);
Set_From_With_Type (Typ);
return;
end if;
Decl := Next (Decl);
end loop;
Error_Msg_NE ("not a visible access or tagged type in&", Nam, P);
end;
end Analyze_With_Type_Clause;
-----------------------------
-- Check_With_Type_Clauses --
-----------------------------
procedure Check_With_Type_Clauses (N : Node_Id) is
Lib_Unit : constant Node_Id := Unit (N);
procedure Check_Parent_Context (U : Node_Id);
-- Examine context items of parent unit to locate with_type clauses.
--------------------------
-- Check_Parent_Context --
--------------------------
procedure Check_Parent_Context (U : Node_Id) is
Item : Node_Id;
begin
Item := First (Context_Items (U));
while Present (Item) loop
if Nkind (Item) = N_With_Type_Clause
and then not Error_Posted (Item)
and then
From_With_Type (Scope (Entity (Selector_Name (Name (Item)))))
then
Error_Msg_Sloc := Sloc (Item);
Error_Msg_N ("Missing With_Clause for With_Type_Clause#", N);
end if;
Next (Item);
end loop;
end Check_Parent_Context;
-- Start of processing for Check_With_Type_Clauses
begin
if Extensions_Allowed
and then (Nkind (Lib_Unit) = N_Package_Body
or else Nkind (Lib_Unit) = N_Subprogram_Body)
then
Check_Parent_Context (Library_Unit (N));
if Is_Child_Spec (Unit (Library_Unit (N))) then
Check_Parent_Context (Parent_Spec (Unit (Library_Unit (N))));
end if;
end if;
end Check_With_Type_Clauses;
------------------------------
-- Check_Private_Child_Unit --
------------------------------
procedure Check_Private_Child_Unit (N : Node_Id) is
Lib_Unit : constant Node_Id := Unit (N);
Item : Node_Id;
Curr_Unit : Entity_Id;
Sub_Parent : Node_Id;
Priv_Child : Entity_Id;
Par_Lib : Entity_Id;
Par_Spec : Node_Id;
function Is_Private_Library_Unit (Unit : Entity_Id) return Boolean;
-- Returns true if and only if the library unit is declared with
-- an explicit designation of private.
function Is_Private_Library_Unit (Unit : Entity_Id) return Boolean is
Comp_Unit : constant Node_Id := Parent (Unit_Declaration_Node (Unit));
begin
return Private_Present (Comp_Unit);
end Is_Private_Library_Unit;
-- Start of processing for Check_Private_Child_Unit
begin
if Nkind (Lib_Unit) = N_Package_Body
or else Nkind (Lib_Unit) = N_Subprogram_Body
then
Curr_Unit := Defining_Entity (Unit (Library_Unit (N)));
Par_Lib := Curr_Unit;
elsif Nkind (Lib_Unit) = N_Subunit then
-- The parent is itself a body. The parent entity is to be found
-- in the corresponding spec.
Sub_Parent := Library_Unit (N);
Curr_Unit := Defining_Entity (Unit (Library_Unit (Sub_Parent)));
-- If the parent itself is a subunit, Curr_Unit is the entity
-- of the enclosing body, retrieve the spec entity which is
-- the proper ancestor we need for the following tests.
if Ekind (Curr_Unit) = E_Package_Body then
Curr_Unit := Spec_Entity (Curr_Unit);
end if;
Par_Lib := Curr_Unit;
else
Curr_Unit := Defining_Entity (Lib_Unit);
Par_Lib := Curr_Unit;
Par_Spec := Parent_Spec (Lib_Unit);
if No (Par_Spec) then
Par_Lib := Empty;
else
Par_Lib := Defining_Entity (Unit (Par_Spec));
end if;
end if;
-- Loop through context items
Item := First (Context_Items (N));
while Present (Item) loop
if Nkind (Item) = N_With_Clause
and then not Implicit_With (Item)
and then Is_Private_Descendant (Entity (Name (Item)))
then
Priv_Child := Entity (Name (Item));
declare
Curr_Parent : Entity_Id := Par_Lib;
Child_Parent : Entity_Id := Scope (Priv_Child);
Prv_Ancestor : Entity_Id := Child_Parent;
Curr_Private : Boolean := Is_Private_Library_Unit (Curr_Unit);
begin
-- If the child unit is a public child then locate
-- the nearest private ancestor; Child_Parent will
-- then be set to the parent of that ancestor.
if not Is_Private_Library_Unit (Priv_Child) then
while Present (Prv_Ancestor)
and then not Is_Private_Library_Unit (Prv_Ancestor)
loop
Prv_Ancestor := Scope (Prv_Ancestor);
end loop;
if Present (Prv_Ancestor) then
Child_Parent := Scope (Prv_Ancestor);
end if;
end if;
while Present (Curr_Parent)
and then Curr_Parent /= Standard_Standard
and then Curr_Parent /= Child_Parent
loop
Curr_Private :=
Curr_Private or else Is_Private_Library_Unit (Curr_Parent);
Curr_Parent := Scope (Curr_Parent);
end loop;
if not Present (Curr_Parent) then
Curr_Parent := Standard_Standard;
end if;
if Curr_Parent /= Child_Parent then
if Ekind (Priv_Child) = E_Generic_Package
and then Chars (Priv_Child) in Text_IO_Package_Name
and then Chars (Scope (Scope (Priv_Child))) = Name_Ada
then
Error_Msg_NE
("& is a nested package, not a compilation unit",
Name (Item), Priv_Child);
else
Error_Msg_N
("unit in with clause is private child unit!", Item);
Error_Msg_NE
("current unit must also have parent&!",
Item, Child_Parent);
end if;
elsif not Curr_Private
and then Nkind (Lib_Unit) /= N_Package_Body
and then Nkind (Lib_Unit) /= N_Subprogram_Body
and then Nkind (Lib_Unit) /= N_Subunit
then
Error_Msg_NE
("current unit must also be private descendant of&",
Item, Child_Parent);
end if;
end;
end if;
Next (Item);
end loop;
end Check_Private_Child_Unit;
----------------------
-- Check_Stub_Level --
----------------------
procedure Check_Stub_Level (N : Node_Id) is
Par : constant Node_Id := Parent (N);
Kind : constant Node_Kind := Nkind (Par);
begin
if (Kind = N_Package_Body
or else Kind = N_Subprogram_Body
or else Kind = N_Task_Body
or else Kind = N_Protected_Body)
and then (Nkind (Parent (Par)) = N_Compilation_Unit
or else Nkind (Parent (Par)) = N_Subunit)
then
null;
-- In an instance, a missing stub appears at any level. A warning
-- message will have been emitted already for the missing file.
elsif not In_Instance then
Error_Msg_N ("stub cannot appear in an inner scope", N);
elsif Expander_Active then
Error_Msg_N ("missing proper body", N);
end if;
end Check_Stub_Level;
------------------------
-- Expand_With_Clause --
------------------------
procedure Expand_With_Clause (Nam : Node_Id; N : Node_Id) is
Loc : constant Source_Ptr := Sloc (Nam);
Ent : constant Entity_Id := Entity (Nam);
Withn : Node_Id;
P : Node_Id;
function Build_Unit_Name (Nam : Node_Id) return Node_Id;
function Build_Unit_Name (Nam : Node_Id) return Node_Id is
Result : Node_Id;
begin
if Nkind (Nam) = N_Identifier then
return New_Occurrence_Of (Entity (Nam), Loc);
else
Result :=
Make_Expanded_Name (Loc,
Chars => Chars (Entity (Nam)),
Prefix => Build_Unit_Name (Prefix (Nam)),
Selector_Name => New_Occurrence_Of (Entity (Nam), Loc));
Set_Entity (Result, Entity (Nam));
return Result;
end if;
end Build_Unit_Name;
begin
New_Nodes_OK := New_Nodes_OK + 1;
Withn :=
Make_With_Clause (Loc, Name => Build_Unit_Name (Nam));
P := Parent (Unit_Declaration_Node (Ent));
Set_Library_Unit (Withn, P);
Set_Corresponding_Spec (Withn, Ent);
Set_First_Name (Withn, True);
Set_Implicit_With (Withn, True);
Prepend (Withn, Context_Items (N));
Mark_Rewrite_Insertion (Withn);
Install_Withed_Unit (Withn);
if Nkind (Nam) = N_Expanded_Name then
Expand_With_Clause (Prefix (Nam), N);
end if;
New_Nodes_OK := New_Nodes_OK - 1;
end Expand_With_Clause;
--------------------------------
-- Expand_Limited_With_Clause --
--------------------------------
procedure Expand_Limited_With_Clause (Nam : Node_Id; N : Node_Id) is
Loc : constant Source_Ptr := Sloc (Nam);
Unum : Unit_Number_Type;
Withn : Node_Id;
begin
New_Nodes_OK := New_Nodes_OK + 1;
if Nkind (Nam) = N_Identifier then
Withn :=
Make_With_Clause (Loc, Name => Nam);
Set_Limited_Present (Withn);
Set_First_Name (Withn);
Set_Implicit_With (Withn);
-- Load the corresponding parent unit
Unum :=
Load_Unit
(Load_Name => Get_Spec_Name (Get_Unit_Name (Nam)),
Required => True,
Subunit => False,
Error_Node => Nam);
if not Analyzed (Cunit (Unum)) then
Set_Library_Unit (Withn, Cunit (Unum));
Set_Corresponding_Spec
(Withn, Specification (Unit (Cunit (Unum))));
Prepend (Withn, Context_Items (Parent (N)));
Mark_Rewrite_Insertion (Withn);
end if;
elsif Nkind (Nam) = N_Selected_Component then
Withn :=
Make_With_Clause
(Loc,
Name =>
Make_Selected_Component
(Loc,
Prefix => Prefix (Nam),
Selector_Name => Selector_Name (Nam)));
Set_Parent (Withn, Parent (N));
Set_Limited_Present (Withn);
Set_First_Name (Withn);
Set_Implicit_With (Withn);
Unum :=
Load_Unit
(Load_Name => Get_Spec_Name (Get_Unit_Name (Nam)),
Required => True,
Subunit => False,
Error_Node => Nam);
if not Analyzed (Cunit (Unum)) then
Set_Library_Unit (Withn, Cunit (Unum));
Set_Corresponding_Spec
(Withn, Specification (Unit (Cunit (Unum))));
Prepend (Withn, Context_Items (Parent (N)));
Mark_Rewrite_Insertion (Withn);
Expand_Limited_With_Clause (Prefix (Nam), N);
end if;
else
null;
pragma Assert (False);
end if;
New_Nodes_OK := New_Nodes_OK - 1;
end Expand_Limited_With_Clause;
-----------------------
-- Get_Parent_Entity --
-----------------------
function Get_Parent_Entity (Unit : Node_Id) return Entity_Id is
begin
if Nkind (Unit) = N_Package_Instantiation then
return Defining_Entity (Specification (Instance_Spec (Unit)));
else
return Defining_Entity (Unit);
end if;
end Get_Parent_Entity;
-----------------------------
-- Implicit_With_On_Parent --
-----------------------------
procedure Implicit_With_On_Parent
(Child_Unit : Node_Id;
N : Node_Id)
is
Loc : constant Source_Ptr := Sloc (N);
P : constant Node_Id := Parent_Spec (Child_Unit);
P_Unit : constant Node_Id := Unit (P);
P_Name : constant Entity_Id := Get_Parent_Entity (P_Unit);
Withn : Node_Id;
function Build_Ancestor_Name (P : Node_Id) return Node_Id;
-- Build prefix of child unit name. Recurse if needed.
function Build_Unit_Name return Node_Id;
-- If the unit is a child unit, build qualified name with all
-- ancestors.
-------------------------
-- Build_Ancestor_Name --
-------------------------
function Build_Ancestor_Name (P : Node_Id) return Node_Id is
P_Ref : constant Node_Id :=
New_Reference_To (Defining_Entity (P), Loc);
begin
if No (Parent_Spec (P)) then
return P_Ref;
else
return
Make_Selected_Component (Loc,
Prefix => Build_Ancestor_Name (Unit (Parent_Spec (P))),
Selector_Name => P_Ref);
end if;
end Build_Ancestor_Name;
---------------------
-- Build_Unit_Name --
---------------------
function Build_Unit_Name return Node_Id is
Result : Node_Id;
begin
if No (Parent_Spec (P_Unit)) then
return New_Reference_To (P_Name, Loc);
else
Result :=
Make_Expanded_Name (Loc,
Chars => Chars (P_Name),
Prefix => Build_Ancestor_Name (Unit (Parent_Spec (P_Unit))),
Selector_Name => New_Reference_To (P_Name, Loc));
Set_Entity (Result, P_Name);
return Result;
end if;
end Build_Unit_Name;
-- Start of processing for Implicit_With_On_Parent
begin
New_Nodes_OK := New_Nodes_OK + 1;
Withn := Make_With_Clause (Loc, Name => Build_Unit_Name);
Set_Library_Unit (Withn, P);
Set_Corresponding_Spec (Withn, P_Name);
Set_First_Name (Withn, True);
Set_Implicit_With (Withn, True);
-- Node is placed at the beginning of the context items, so that
-- subsequent use clauses on the parent can be validated.
Prepend (Withn, Context_Items (N));
Mark_Rewrite_Insertion (Withn);
Install_Withed_Unit (Withn);
if Is_Child_Spec (P_Unit) then
Implicit_With_On_Parent (P_Unit, N);
end if;
New_Nodes_OK := New_Nodes_OK - 1;
end Implicit_With_On_Parent;
---------------------
-- Install_Context --
---------------------
procedure Install_Context (N : Node_Id) is
Lib_Unit : constant Node_Id := Unit (N);
begin
Install_Context_Clauses (N);
if Is_Child_Spec (Lib_Unit) then
Install_Parents (Lib_Unit, Private_Present (Parent (Lib_Unit)));
end if;
Install_Limited_Context_Clauses (N);
Check_With_Type_Clauses (N);
end Install_Context;
-----------------------------
-- Install_Context_Clauses --
-----------------------------
procedure Install_Context_Clauses (N : Node_Id) is
Lib_Unit : constant Node_Id := Unit (N);
Item : Node_Id;
Uname_Node : Entity_Id;
Check_Private : Boolean := False;
Decl_Node : Node_Id;
Lib_Parent : Entity_Id;
begin
-- Loop through context clauses to find the with/use clauses.
-- This is done twice, first for everything except limited_with
-- clauses, and then for those, if any are present.
Item := First (Context_Items (N));
while Present (Item) loop
-- Case of explicit WITH clause
if Nkind (Item) = N_With_Clause
and then not Implicit_With (Item)
then
if Limited_Present (Item) then
-- Limited withed units will be installed later.
goto Continue;
-- If Name (Item) is not an entity name, something is wrong, and
-- this will be detected in due course, for now ignore the item
elsif not Is_Entity_Name (Name (Item)) then
goto Continue;
elsif No (Entity (Name (Item))) then
Set_Entity (Name (Item), Any_Id);
goto Continue;
end if;
Uname_Node := Entity (Name (Item));
if Is_Private_Descendant (Uname_Node) then
Check_Private := True;
end if;
Install_Withed_Unit (Item);
Decl_Node := Unit_Declaration_Node (Uname_Node);
-- If the unit is a subprogram instance, it appears nested
-- within a package that carries the parent information.
if Is_Generic_Instance (Uname_Node)
and then Ekind (Uname_Node) /= E_Package
then
Decl_Node := Parent (Parent (Decl_Node));
end if;
if Is_Child_Spec (Decl_Node) then
if Nkind (Name (Item)) = N_Expanded_Name then
Expand_With_Clause (Prefix (Name (Item)), N);
else
-- if not an expanded name, the child unit must be a
-- renaming, nothing to do.
null;
end if;
elsif Nkind (Decl_Node) = N_Subprogram_Body
and then not Acts_As_Spec (Parent (Decl_Node))
and then Is_Child_Spec (Unit (Library_Unit (Parent (Decl_Node))))
then
Implicit_With_On_Parent
(Unit (Library_Unit (Parent (Decl_Node))), N);
end if;
-- Check license conditions unless this is a dummy unit
if Sloc (Library_Unit (Item)) /= No_Location then
License_Check : declare
Withl : constant License_Type :=
License (Source_Index
(Get_Source_Unit
(Library_Unit (Item))));
Unitl : constant License_Type :=
License (Source_Index (Current_Sem_Unit));
procedure License_Error;
-- Signal error of bad license
-------------------
-- License_Error --
-------------------
procedure License_Error is
begin
Error_Msg_N
("?license of with'ed unit & is incompatible",
Name (Item));
end License_Error;
-- Start of processing for License_Check
begin
case Unitl is
when Unknown =>
null;
when Restricted =>
if Withl = GPL then
License_Error;
end if;
when GPL =>
if Withl = Restricted then
License_Error;
end if;
when Modified_GPL =>
if Withl = Restricted or else Withl = GPL then
License_Error;
end if;
when Unrestricted =>
null;
end case;
end License_Check;
end if;
-- Case of USE PACKAGE clause
elsif Nkind (Item) = N_Use_Package_Clause then
Analyze_Use_Package (Item);
-- Case of USE TYPE clause
elsif Nkind (Item) = N_Use_Type_Clause then
Analyze_Use_Type (Item);
-- Case of WITH TYPE clause
-- A With_Type_Clause is processed when installing the context,
-- because it is a visibility mechanism and does not create a
-- semantic dependence on other units, as a With_Clause does.
elsif Nkind (Item) = N_With_Type_Clause then
Analyze_With_Type_Clause (Item);
-- case of PRAGMA
elsif Nkind (Item) = N_Pragma then
Analyze (Item);
end if;
<<Continue>>
Next (Item);
end loop;
if Is_Child_Spec (Lib_Unit) then
-- The unit also has implicit withs on its own parents
if No (Context_Items (N)) then
Set_Context_Items (N, New_List);
end if;
Implicit_With_On_Parent (Lib_Unit, N);
end if;
-- If the unit is a body, the context of the specification must also
-- be installed.
if Nkind (Lib_Unit) = N_Package_Body
or else (Nkind (Lib_Unit) = N_Subprogram_Body
and then not Acts_As_Spec (N))
then
Install_Context (Library_Unit (N));
if Is_Child_Spec (Unit (Library_Unit (N))) then
-- If the unit is the body of a public child unit, the private
-- declarations of the parent must be made visible. If the child
-- unit is private, the private declarations have been installed
-- already in the call to Install_Parents for the spec. Installing
-- private declarations must be done for all ancestors of public
-- child units. In addition, sibling units mentioned in the
-- context clause of the body are directly visible.
declare
Lib_Spec : Node_Id := Unit (Library_Unit (N));
P : Node_Id;
P_Name : Entity_Id;
begin
while Is_Child_Spec (Lib_Spec) loop
P := Unit (Parent_Spec (Lib_Spec));
if not (Private_Present (Parent (Lib_Spec))) then
P_Name := Defining_Entity (P);
Install_Private_Declarations (P_Name);
Set_Use (Private_Declarations (Specification (P)));
end if;
Lib_Spec := P;
end loop;
end;
end if;
-- For a package body, children in context are immediately visible
Install_Siblings (Defining_Entity (Unit (Library_Unit (N))), N);
end if;
if Nkind (Lib_Unit) = N_Generic_Package_Declaration
or else Nkind (Lib_Unit) = N_Generic_Subprogram_Declaration
or else Nkind (Lib_Unit) = N_Package_Declaration
or else Nkind (Lib_Unit) = N_Subprogram_Declaration
then
if Is_Child_Spec (Lib_Unit) then
Lib_Parent := Defining_Entity (Unit (Parent_Spec (Lib_Unit)));
Set_Is_Private_Descendant
(Defining_Entity (Lib_Unit),
Is_Private_Descendant (Lib_Parent)
or else Private_Present (Parent (Lib_Unit)));
else
Set_Is_Private_Descendant
(Defining_Entity (Lib_Unit),
Private_Present (Parent (Lib_Unit)));
end if;
end if;
if Check_Private then
Check_Private_Child_Unit (N);
end if;
end Install_Context_Clauses;
-------------------------------------
-- Install_Limited_Context_Clauses --
-------------------------------------
procedure Install_Limited_Context_Clauses (N : Node_Id) is
Item : Node_Id;
procedure Check_Parent (P : Node_Id; W : Node_Id);
-- Check that the unlimited view of a given compilation_unit is not
-- already visible in the parents (neither immediately through the
-- context clauses, nor indirectly through "use + renamings").
procedure Check_Private_Limited_Withed_Unit (N : Node_Id);
-- Check that if a limited_with clause of a given compilation_unit
-- mentions a private child of some library unit, then the given
-- compilation_unit shall be the declaration of a private descendant
-- of that library unit.
procedure Check_Withed_Unit (W : Node_Id);
-- Check that a limited with_clause does not appear in the same
-- context_clause as a nonlimited with_clause that mentions
-- the same library.
--------------------
-- Check_Parent --
--------------------
procedure Check_Parent (P : Node_Id; W : Node_Id) is
Item : Node_Id;
Spec : Node_Id;
WEnt : Entity_Id;
Nam : Node_Id;
E : Entity_Id;
E2 : Entity_Id;
begin
pragma Assert (Nkind (W) = N_With_Clause);
-- Step 1: Check if the unlimited view is installed in the parent
Item := First (Context_Items (P));
while Present (Item) loop
if Nkind (Item) = N_With_Clause
and then not Limited_Present (Item)
and then not Implicit_With (Item)
and then Library_Unit (Item) = Library_Unit (W)
then
Error_Msg_N ("unlimited view visible in ancestor", W);
return;
end if;
Next (Item);
end loop;
-- Step 2: Check "use + renamings"
WEnt := Defining_Unit_Name (Specification (Unit (Library_Unit (W))));
Spec := Specification (Unit (P));
-- We tried to traverse the list of entities corresponding to the
-- defining entity of the package spec. However, first_entity was
-- found to be 'empty'. Don't know why???
-- Def := Defining_Unit_Name (Spec);
-- Ent := First_Entity (Def);
-- As a workaround we traverse the list of visible declarations ???
Item := First (Visible_Declarations (Spec));
while Present (Item) loop
if Nkind (Item) = N_Use_Package_Clause then
-- Traverse the list of packages
Nam := First (Names (Item));
while Present (Nam) loop
E := Entity (Nam);
pragma Assert (Present (Parent (E)));
if Nkind (Parent (E))
= N_Package_Renaming_Declaration
and then Renamed_Entity (E) = WEnt
then
Error_Msg_N ("unlimited view visible through "
& "use_clause + renamings", W);
return;
elsif Nkind (Parent (E)) = N_Package_Specification then
-- The use clause may refer to a local package.
-- Check all the enclosing scopes.
E2 := E;
while E2 /= Standard_Standard
and then E2 /= WEnt loop
E2 := Scope (E2);
end loop;
if E2 = WEnt then
Error_Msg_N ("unlimited view visible through "
& "use_clause ", W);
return;
end if;
end if;
Next (Nam);
end loop;
end if;
Next (Item);
end loop;
-- Recursive call to check all the ancestors
if Is_Child_Spec (Unit (P)) then
Check_Parent (P => Parent_Spec (Unit (P)), W => W);
end if;
end Check_Parent;
---------------------------------------
-- Check_Private_Limited_Withed_Unit --
---------------------------------------
procedure Check_Private_Limited_Withed_Unit (N : Node_Id) is
C : Node_Id;
P : Node_Id;
Found : Boolean := False;
begin
-- If the current compilation unit is not private we don't
-- need to check anything else.
if not Private_Present (Parent (N)) then
Found := False;
else
-- Compilation unit of the parent of the withed library unit
P := Parent_Spec (Unit (Library_Unit (N)));
-- Traverse all the ancestors of the current compilation
-- unit to check if it is a descendant of named library unit.
C := Parent (N);
while Present (Parent_Spec (Unit (C))) loop
C := Parent_Spec (Unit (C));
if C = P then
Found := True;
exit;
end if;
end loop;
end if;
if not Found then
Error_Msg_N ("current unit is not a private descendant"
& " of the withed unit ('R'M 10.1.2(8)", N);
end if;
end Check_Private_Limited_Withed_Unit;
-----------------------
-- Check_Withed_Unit --
-----------------------
procedure Check_Withed_Unit (W : Node_Id) is
Item : Node_Id;
begin
-- A limited with_clause can not appear in the same context_clause
-- as a nonlimited with_clause which mentions the same library.
Item := First (Context_Items (N));
while Present (Item) loop
if Nkind (Item) = N_With_Clause
and then not Limited_Present (Item)
and then not Implicit_With (Item)
and then Library_Unit (Item) = Library_Unit (W)
then
Error_Msg_N ("limited and unlimited view "
& "not allowed in the same context clauses", W);
return;
end if;
Next (Item);
end loop;
end Check_Withed_Unit;
-- Start of processing for Install_Limited_Context_Clauses
begin
Item := First (Context_Items (N));
while Present (Item) loop
if Nkind (Item) = N_With_Clause
and then Limited_Present (Item)
then
Check_Withed_Unit (Item);
if Private_Present (Library_Unit (Item)) then
Check_Private_Limited_Withed_Unit (Item);
end if;
if Is_Child_Spec (Unit (N)) then
Check_Parent (Parent_Spec (Unit (N)), Item);
end if;
Install_Limited_Withed_Unit (Item);
end if;
Next (Item);
end loop;
end Install_Limited_Context_Clauses;
---------------------
-- Install_Parents --
---------------------
procedure Install_Parents (Lib_Unit : Node_Id; Is_Private : Boolean) is
P : Node_Id;
E_Name : Entity_Id;
P_Name : Entity_Id;
P_Spec : Node_Id;
begin
P := Unit (Parent_Spec (Lib_Unit));
P_Name := Get_Parent_Entity (P);
if Etype (P_Name) = Any_Type then
return;
end if;
if Ekind (P_Name) = E_Generic_Package
and then Nkind (Lib_Unit) /= N_Generic_Subprogram_Declaration
and then Nkind (Lib_Unit) /= N_Generic_Package_Declaration
and then Nkind (Lib_Unit) not in N_Generic_Renaming_Declaration
then
Error_Msg_N
("child of a generic package must be a generic unit", Lib_Unit);
elsif not Is_Package (P_Name) then
Error_Msg_N
("parent unit must be package or generic package", Lib_Unit);
raise Unrecoverable_Error;
elsif Present (Renamed_Object (P_Name)) then
Error_Msg_N ("parent unit cannot be a renaming", Lib_Unit);
raise Unrecoverable_Error;
-- Verify that a child of an instance is itself an instance, or
-- the renaming of one. Given that an instance that is a unit is
-- replaced with a package declaration, check against the original
-- node.
elsif Nkind (Original_Node (P)) = N_Package_Instantiation
and then Nkind (Lib_Unit)
not in N_Renaming_Declaration
and then Nkind (Original_Node (Lib_Unit))
not in N_Generic_Instantiation
then
Error_Msg_N
("child of an instance must be an instance or renaming", Lib_Unit);
end if;
-- This is the recursive call that ensures all parents are loaded
if Is_Child_Spec (P) then
Install_Parents (P,
Is_Private or else Private_Present (Parent (Lib_Unit)));
end if;
-- Now we can install the context for this parent
Install_Context_Clauses (Parent_Spec (Lib_Unit));
Install_Siblings (P_Name, Parent (Lib_Unit));
-- The child unit is in the declarative region of the parent. The
-- parent must therefore appear in the scope stack and be visible,
-- as when compiling the corresponding body. If the child unit is
-- private or it is a package body, private declarations must be
-- accessible as well. Use declarations in the parent must also
-- be installed. Finally, other child units of the same parent that
-- are in the context are immediately visible.
-- Find entity for compilation unit, and set its private descendant
-- status as needed.
E_Name := Defining_Entity (Lib_Unit);
Set_Is_Child_Unit (E_Name);
Set_Is_Private_Descendant (E_Name,
Is_Private_Descendant (P_Name)
or else Private_Present (Parent (Lib_Unit)));
P_Spec := Specification (Unit_Declaration_Node (P_Name));
New_Scope (P_Name);
-- Save current visibility of unit
Scope_Stack.Table (Scope_Stack.Last).Previous_Visibility :=
Is_Immediately_Visible (P_Name);
Set_Is_Immediately_Visible (P_Name);
Install_Visible_Declarations (P_Name);
Set_Use (Visible_Declarations (P_Spec));
-- If the parent is a generic unit, its formal part may contain
-- formal packages and use clauses for them.
if Ekind (P_Name) = E_Generic_Package then
Set_Use (Generic_Formal_Declarations (Parent (P_Spec)));
end if;
if Is_Private
or else Private_Present (Parent (Lib_Unit))
then
Install_Private_Declarations (P_Name);
Set_Use (Private_Declarations (P_Spec));
end if;
end Install_Parents;
----------------------
-- Install_Siblings --
----------------------
procedure Install_Siblings (U_Name : Entity_Id; N : Node_Id) is
Item : Node_Id;
Id : Entity_Id;
Prev : Entity_Id;
function Is_Ancestor (E : Entity_Id) return Boolean;
-- Determine whether the scope of a child unit is an ancestor of
-- the current unit.
-- Shouldn't this be somewhere more general ???
-----------------
-- Is_Ancestor --
-----------------
function Is_Ancestor (E : Entity_Id) return Boolean is
Par : Entity_Id;
begin
Par := U_Name;
while Present (Par)
and then Par /= Standard_Standard
loop
if Par = E then
return True;
end if;
Par := Scope (Par);
end loop;
return False;
end Is_Ancestor;
-- Start of processing for Install_Siblings
begin
-- Iterate over explicit with clauses, and check whether the
-- scope of each entity is an ancestor of the current unit.
Item := First (Context_Items (N));
while Present (Item) loop
if Nkind (Item) = N_With_Clause
and then not Implicit_With (Item)
and then not Limited_Present (Item)
then
Id := Entity (Name (Item));
if Is_Child_Unit (Id)
and then Is_Ancestor (Scope (Id))
then
Set_Is_Immediately_Visible (Id);
Prev := Current_Entity (Id);
-- Check for the presence of another unit in the context,
-- that may be inadvertently hidden by the child.
if Present (Prev)
and then Is_Immediately_Visible (Prev)
and then not Is_Child_Unit (Prev)
then
declare
Clause : Node_Id;
begin
Clause := First (Context_Items (N));
while Present (Clause) loop
if Nkind (Clause) = N_With_Clause
and then Entity (Name (Clause)) = Prev
then
Error_Msg_NE
("child unit& hides compilation unit " &
"with the same name?",
Name (Item), Id);
exit;
end if;
Next (Clause);
end loop;
end;
end if;
-- the With_Clause may be on a grand-child, which makes
-- the child immediately visible.
elsif Is_Child_Unit (Scope (Id))
and then Is_Ancestor (Scope (Scope (Id)))
then
Set_Is_Immediately_Visible (Scope (Id));
end if;
end if;
Next (Item);
end loop;
end Install_Siblings;
-------------------------------
-- Install_Limited_With_Unit --
-------------------------------
procedure Install_Limited_Withed_Unit (N : Node_Id) is
Unum : constant Unit_Number_Type :=
Get_Source_Unit (Library_Unit (N));
P_Unit : constant Entity_Id := Unit (Library_Unit (N));
P : Entity_Id;
Lim_Elmt : Elmt_Id;
Lim_Typ : Entity_Id;
Is_Child_Package : Boolean := False;
function In_Chain (E : Entity_Id) return Boolean;
-- Check that the shadow entity is not already in the homonym
-- chain, for example through a limited_with clause in a parent unit.
function In_Chain (E : Entity_Id) return Boolean is
H : Entity_Id := Current_Entity (E);
begin
while Present (H) loop
if H = E then
return True;
else
H := Homonym (H);
end if;
end loop;
return False;
end In_Chain;
-- Start of processing for Install_Limited_Withed_Unit
begin
-- In case of limited with_clause on subprograms, generics, instances,
-- or generic renamings, the corresponding error was previously posted
-- and we have nothing to do here.
case Nkind (P_Unit) is
when N_Package_Declaration =>
null;
when N_Subprogram_Declaration |
N_Generic_Package_Declaration |
N_Generic_Subprogram_Declaration |
N_Package_Instantiation |
N_Function_Instantiation |
N_Procedure_Instantiation |
N_Generic_Package_Renaming_Declaration |
N_Generic_Procedure_Renaming_Declaration |
N_Generic_Function_Renaming_Declaration =>
return;
when others =>
pragma Assert (False);
null;
end case;
P := Defining_Unit_Name (Specification (P_Unit));
if Nkind (P) = N_Defining_Program_Unit_Name then
-- Retrieve entity of child package
Is_Child_Package := True;
P := Defining_Identifier (P);
end if;
-- A common usage of the limited-with is to have a limited-with
-- in the package spec, and a normal with in its package body.
-- For example:
-- limited with X; -- [1]
-- package A is ...
-- with X; -- [2]
-- package body A is ...
-- The compilation of A's body installs the entities of its
-- withed packages (the context clauses found at [2]) and
-- then the context clauses of its specification (found at [1]).
-- As a consequence, at point [1] the specification of X has been
-- analyzed and it is immediately visible. According to the semantics
-- of the limited-with context clauses we don't install the limited
-- view because the full view of X supersedes its limited view.
if Analyzed (Cunit (Unum))
and then Is_Immediately_Visible (P)
then
return;
end if;
if Debug_Flag_I then
Write_Str ("install limited view of ");
Write_Name (Chars (P));
Write_Eol;
end if;
if not Analyzed (Cunit (Unum)) then
Set_Ekind (P, E_Package);
Set_Etype (P, Standard_Void_Type);
Set_Scope (P, Standard_Standard);
-- Place entity on visibility structure
if Current_Entity (P) /= P then
Set_Homonym (P, Current_Entity (P));
Set_Current_Entity (P);
if Debug_Flag_I then
Write_Str (" (homonym) chain ");
Write_Name (Chars (P));
Write_Eol;
end if;
end if;
if Is_Child_Package then
Set_Is_Child_Unit (P);
Set_Is_Visible_Child_Unit (P);
declare
Parent_Comp : Node_Id;
Parent_Id : Entity_Id;
begin
Parent_Comp := Parent_Spec (Unit (Cunit (Unum)));
Parent_Id := Defining_Entity (Unit (Parent_Comp));
Set_Scope (P, Parent_Id);
end;
end if;
else
-- If the unit appears in a previous regular with_clause, the
-- regular entities must be unchained before the shadow ones
-- are made accessible.
declare
Ent : Entity_Id;
begin
Ent := First_Entity (P);
while Present (Ent) loop
Unchain (Ent);
Next_Entity (Ent);
end loop;
end;
end if;
-- The package must be visible while the with_type clause is active,
-- because references to the type P.T must resolve in the usual way.
Set_Is_Immediately_Visible (P);
-- Install each incomplete view
Lim_Elmt := First_Elmt (Limited_Views (P));
while Present (Lim_Elmt) loop
Lim_Typ := Node (Lim_Elmt);
if not In_Chain (Lim_Typ) then
Set_Homonym (Lim_Typ, Current_Entity (Lim_Typ));
Set_Current_Entity (Lim_Typ);
if Debug_Flag_I then
Write_Str (" (homonym) chain ");
Write_Name (Chars (Lim_Typ));
Write_Eol;
end if;
end if;
Next_Elmt (Lim_Elmt);
end loop;
-- The context clause has installed a limited-view, mark it
-- accordingly, to uninstall it when the context is removed.
Set_Limited_View_Installed (N);
Set_From_With_Type (P);
end Install_Limited_Withed_Unit;
-------------------------
-- Install_Withed_Unit --
-------------------------
procedure Install_Withed_Unit (With_Clause : Node_Id) is
Uname : constant Entity_Id := Entity (Name (With_Clause));
P : constant Entity_Id := Scope (Uname);
begin
if Debug_Flag_I then
Write_Str ("install withed unit ");
Write_Name (Chars (Uname));
Write_Eol;
end if;
-- We do not apply the restrictions to an internal unit unless
-- we are compiling the internal unit as a main unit. This check
-- is also skipped for dummy units (for missing packages).
if Sloc (Uname) /= No_Location
and then (not Is_Internal_File_Name (Unit_File_Name (Current_Sem_Unit))
or else Current_Sem_Unit = Main_Unit)
then
Check_Restricted_Unit
(Unit_Name (Get_Source_Unit (Uname)), With_Clause);
end if;
if P /= Standard_Standard then
-- If the unit is not analyzed after analysis of the with clause,
-- and it is an instantiation, then it awaits a body and is the main
-- unit. Its appearance in the context of some other unit indicates
-- a circular dependency (DEC suite perversity).
if not Analyzed (Uname)
and then Nkind (Parent (Uname)) = N_Package_Instantiation
then
Error_Msg_N
("instantiation depends on itself", Name (With_Clause));
elsif not Is_Visible_Child_Unit (Uname) then
Set_Is_Visible_Child_Unit (Uname);
if Is_Generic_Instance (Uname)
and then Ekind (Uname) in Subprogram_Kind
then
-- Set flag as well on the visible entity that denotes the
-- instance, which renames the current one.
Set_Is_Visible_Child_Unit
(Related_Instance
(Defining_Entity (Unit (Library_Unit (With_Clause)))));
null;
end if;
-- The parent unit may have been installed already, and
-- may have appeared in a use clause.
if In_Use (Scope (Uname)) then
Set_Is_Potentially_Use_Visible (Uname);
end if;
Set_Context_Installed (With_Clause);
end if;
elsif not Is_Immediately_Visible (Uname) then
Set_Is_Immediately_Visible (Uname);
Set_Context_Installed (With_Clause);
end if;
-- A with-clause overrides a with-type clause: there are no restric-
-- tions on the use of package entities.
if Ekind (Uname) = E_Package then
Set_From_With_Type (Uname, False);
end if;
end Install_Withed_Unit;
-------------------
-- Is_Child_Spec --
-------------------
function Is_Child_Spec (Lib_Unit : Node_Id) return Boolean is
K : constant Node_Kind := Nkind (Lib_Unit);
begin
return (K in N_Generic_Declaration or else
K in N_Generic_Instantiation or else
K in N_Generic_Renaming_Declaration or else
K = N_Package_Declaration or else
K = N_Package_Renaming_Declaration or else
K = N_Subprogram_Declaration or else
K = N_Subprogram_Renaming_Declaration)
and then Present (Parent_Spec (Lib_Unit));
end Is_Child_Spec;
-----------------------
-- Load_Needed_Body --
-----------------------
-- N is a generic unit named in a with clause, or else it is
-- a unit that contains a generic unit or an inlined function.
-- In order to perform an instantiation, the body of the unit
-- must be present. If the unit itself is generic, we assume
-- that an instantiation follows, and load and analyze the body
-- unconditionally. This forces analysis of the spec as well.
-- If the unit is not generic, but contains a generic unit, it
-- is loaded on demand, at the point of instantiation (see ch12).
procedure Load_Needed_Body (N : Node_Id; OK : out Boolean) is
Body_Name : Unit_Name_Type;
Unum : Unit_Number_Type;
Save_Style_Check : constant Boolean := Opt.Style_Check;
-- The loading and analysis is done with style checks off
begin
if not GNAT_Mode then
Style_Check := False;
end if;
Body_Name := Get_Body_Name (Get_Unit_Name (Unit (N)));
Unum :=
Load_Unit
(Load_Name => Body_Name,
Required => False,
Subunit => False,
Error_Node => N,
Renamings => True);
if Unum = No_Unit then
OK := False;
else
Compiler_State := Analyzing; -- reset after load
if not Fatal_Error (Unum) or else Try_Semantics then
if Debug_Flag_L then
Write_Str ("*** Loaded generic body");
Write_Eol;
end if;
Semantics (Cunit (Unum));
end if;
OK := True;
end if;
Style_Check := Save_Style_Check;
end Load_Needed_Body;
-------------------------
-- Build_Limited_Views --
-------------------------
procedure Build_Limited_Views (N : Node_Id) is
Unum : constant Unit_Number_Type := Get_Source_Unit (Library_Unit (N));
P : constant Entity_Id := Cunit_Entity (Unum);
Spec : Node_Id; -- To denote a package specification
Lim_Typ : Entity_Id; -- To denote shadow entities.
Comp_Typ : Entity_Id; -- To denote real entities.
procedure Decorate_Incomplete_Type
(E : Entity_Id;
Scop : Entity_Id);
-- Add attributes of an incomplete type to a shadow entity. The same
-- attributes are placed on the real entity, so that gigi receives
-- a consistent view.
procedure Decorate_Package_Specification (P : Entity_Id);
-- Add attributes of a package entity to the entity in a package
-- declaration
procedure Decorate_Tagged_Type
(Loc : Source_Ptr;
T : Entity_Id;
Scop : Entity_Id);
-- Set basic attributes of tagged type T, including its class_wide type.
-- The parameters Loc, Scope are used to decorate the class_wide type.
procedure Build_Chain (Spec : Node_Id; Scope : Entity_Id);
-- Construct list of shadow entities and attach it to entity of
-- package that is mentioned in a limited_with clause.
function New_Internal_Shadow_Entity
(Kind : Entity_Kind;
Sloc_Value : Source_Ptr;
Id_Char : Character) return Entity_Id;
-- This function is similar to New_Internal_Entity, except that the
-- entity is not added to the scope's list of entities.
------------------------------
-- Decorate_Incomplete_Type --
------------------------------
procedure Decorate_Incomplete_Type
(E : Entity_Id;
Scop : Entity_Id)
is
begin
Set_Ekind (E, E_Incomplete_Type);
Set_Scope (E, Scop);
Set_Etype (E, E);
Set_Is_First_Subtype (E, True);
Set_Stored_Constraint (E, No_Elist);
Set_Full_View (E, Empty);
Init_Size_Align (E);
end Decorate_Incomplete_Type;
--------------------------
-- Decorate_Tagged_Type --
--------------------------
procedure Decorate_Tagged_Type
(Loc : Source_Ptr;
T : Entity_Id;
Scop : Entity_Id)
is
CW : Entity_Id;
begin
Decorate_Incomplete_Type (T, Scop);
Set_Is_Tagged_Type (T);
-- Build corresponding class_wide type, if not previously done
if No (Class_Wide_Type (T)) then
CW := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
Set_Ekind (CW, E_Class_Wide_Type);
Set_Etype (CW, T);
Set_Scope (CW, Scop);
Set_Is_Tagged_Type (CW);
Set_Is_First_Subtype (CW, True);
Init_Size_Align (CW);
Set_Has_Unknown_Discriminants (CW, True);
Set_Class_Wide_Type (CW, CW);
Set_Equivalent_Type (CW, Empty);
Set_From_With_Type (CW, From_With_Type (T));
Set_Class_Wide_Type (T, CW);
end if;
end Decorate_Tagged_Type;
------------------------------------
-- Decorate_Package_Specification --
------------------------------------
procedure Decorate_Package_Specification (P : Entity_Id) is
begin
-- Place only the most basic attributes
Set_Ekind (P, E_Package);
Set_Etype (P, Standard_Void_Type);
end Decorate_Package_Specification;
-------------------------
-- New_Internal_Entity --
-------------------------
function New_Internal_Shadow_Entity
(Kind : Entity_Kind;
Sloc_Value : Source_Ptr;
Id_Char : Character) return Entity_Id
is
N : constant Entity_Id :=
Make_Defining_Identifier (Sloc_Value,
Chars => New_Internal_Name (Id_Char));
begin
Set_Ekind (N, Kind);
Set_Is_Internal (N, True);
if Kind in Type_Kind then
Init_Size_Align (N);
end if;
return N;
end New_Internal_Shadow_Entity;
-----------------
-- Build_Chain --
-----------------
-- Could use more comments below ???
procedure Build_Chain (Spec : Node_Id; Scope : Entity_Id) is
Analyzed_Unit : constant Boolean := Analyzed (Cunit (Unum));
Is_Tagged : Boolean;
Decl : Node_Id;
begin
Decl := First (Visible_Declarations (Spec));
while Present (Decl) loop
if Nkind (Decl) = N_Full_Type_Declaration then
Is_Tagged :=
Nkind (Type_Definition (Decl)) = N_Record_Definition
and then Tagged_Present (Type_Definition (Decl));
Comp_Typ := Defining_Identifier (Decl);
if not Analyzed_Unit then
if Is_Tagged then
Decorate_Tagged_Type (Sloc (Decl), Comp_Typ, Scope);
else
Decorate_Incomplete_Type (Comp_Typ, Scope);
end if;
end if;
-- Create shadow entity for type
Lim_Typ := New_Internal_Shadow_Entity
(Kind => Ekind (Comp_Typ),
Sloc_Value => Sloc (Comp_Typ),
Id_Char => 'Z');
Set_Chars (Lim_Typ, Chars (Comp_Typ));
Set_Parent (Lim_Typ, Parent (Comp_Typ));
Set_From_With_Type (Lim_Typ);
if Is_Tagged then
Decorate_Tagged_Type (Sloc (Decl), Lim_Typ, Scope);
else
Decorate_Incomplete_Type (Lim_Typ, Scope);
end if;
Set_Non_Limited_View (Lim_Typ, Comp_Typ);
Append_Elmt (Lim_Typ, To => Limited_Views (P));
elsif Nkind (Decl) = N_Private_Type_Declaration
and then Tagged_Present (Decl)
then
Comp_Typ := Defining_Identifier (Decl);
if not Analyzed_Unit then
Decorate_Tagged_Type (Sloc (Decl), Comp_Typ, Scope);
end if;
Lim_Typ := New_Internal_Shadow_Entity
(Kind => Ekind (Comp_Typ),
Sloc_Value => Sloc (Comp_Typ),
Id_Char => 'Z');
Set_Chars (Lim_Typ, Chars (Comp_Typ));
Set_Parent (Lim_Typ, Parent (Comp_Typ));
Set_From_With_Type (Lim_Typ);
Decorate_Tagged_Type (Sloc (Decl), Lim_Typ, Scope);
Set_Non_Limited_View (Lim_Typ, Comp_Typ);
Append_Elmt (Lim_Typ, To => Limited_Views (P));
elsif Nkind (Decl) = N_Package_Declaration then
-- Local package
declare
Spec : constant Node_Id := Specification (Decl);
begin
Comp_Typ := Defining_Unit_Name (Spec);
if not Analyzed (Cunit (Unum)) then
Decorate_Package_Specification (Comp_Typ);
Set_Scope (Comp_Typ, Scope);
end if;
Lim_Typ := New_Internal_Shadow_Entity
(Kind => Ekind (Comp_Typ),
Sloc_Value => Sloc (Comp_Typ),
Id_Char => 'Z');
Decorate_Package_Specification (Lim_Typ);
Set_Scope (Lim_Typ, Scope);
Set_Chars (Lim_Typ, Chars (Comp_Typ));
Set_Parent (Lim_Typ, Parent (Comp_Typ));
Set_From_With_Type (Lim_Typ);
-- Note: The non_limited_view attribute is not used
-- for local packages.
Append_Elmt (Lim_Typ, To => Limited_Views (P));
Build_Chain (Spec, Scope => Lim_Typ);
end;
end if;
Next (Decl);
end loop;
end Build_Chain;
-- Start of processing for Build_Limited_Views
begin
pragma Assert (Limited_Present (N));
-- A library_item mentioned in a limited_with_clause shall be
-- a package_declaration, not a subprogram_declaration,
-- generic_declaration, generic_instantiation, or
-- package_renaming_declaration
case Nkind (Unit (Library_Unit (N))) is
when N_Package_Declaration =>
null;
when N_Subprogram_Declaration =>
Error_Msg_N ("subprograms not allowed in "
& "limited with_clauses", N);
return;
when N_Generic_Package_Declaration |
N_Generic_Subprogram_Declaration =>
Error_Msg_N ("generics not allowed in "
& "limited with_clauses", N);
return;
when N_Package_Instantiation |
N_Function_Instantiation |
N_Procedure_Instantiation =>
Error_Msg_N ("generic instantiations not allowed in "
& "limited with_clauses", N);
return;
when N_Generic_Package_Renaming_Declaration |
N_Generic_Procedure_Renaming_Declaration |
N_Generic_Function_Renaming_Declaration =>
Error_Msg_N ("generic renamings not allowed in "
& "limited with_clauses", N);
return;
when others =>
pragma Assert (False);
null;
end case;
-- Check if the chain is already built
Spec := Specification (Unit (Library_Unit (N)));
if Limited_View_Installed (Spec) then
return;
end if;
Set_Ekind (P, E_Package);
Set_Limited_Views (P, New_Elmt_List);
-- Set_Entity (Name (N), P);
-- Create the auxiliary chain
Build_Chain (Spec, Scope => P);
Set_Limited_View_Installed (Spec);
end Build_Limited_Views;
-------------------------------
-- Check_Body_Needed_For_SAL --
-------------------------------
procedure Check_Body_Needed_For_SAL (Unit_Name : Entity_Id) is
function Entity_Needs_Body (E : Entity_Id) return Boolean;
-- Determine whether use of entity E might require the presence
-- of its body. For a package this requires a recursive traversal
-- of all nested declarations.
---------------------------
-- Entity_Needed_For_SAL --
---------------------------
function Entity_Needs_Body (E : Entity_Id) return Boolean is
Ent : Entity_Id;
begin
if Is_Subprogram (E)
and then Has_Pragma_Inline (E)
then
return True;
elsif Ekind (E) = E_Generic_Function
or else Ekind (E) = E_Generic_Procedure
then
return True;
elsif Ekind (E) = E_Generic_Package
and then
Nkind (Unit_Declaration_Node (E)) = N_Generic_Package_Declaration
and then Present (Corresponding_Body (Unit_Declaration_Node (E)))
then
return True;
elsif Ekind (E) = E_Package
and then
Nkind (Unit_Declaration_Node (E)) = N_Package_Declaration
and then Present (Corresponding_Body (Unit_Declaration_Node (E)))
then
Ent := First_Entity (E);
while Present (Ent) loop
if Entity_Needs_Body (Ent) then
return True;
end if;
Next_Entity (Ent);
end loop;
return False;
else
return False;
end if;
end Entity_Needs_Body;
-- Start of processing for Check_Body_Needed_For_SAL
begin
if Ekind (Unit_Name) = E_Generic_Package
and then
Nkind (Unit_Declaration_Node (Unit_Name)) =
N_Generic_Package_Declaration
and then
Present (Corresponding_Body (Unit_Declaration_Node (Unit_Name)))
then
Set_Body_Needed_For_SAL (Unit_Name);
elsif Ekind (Unit_Name) = E_Generic_Procedure
or else Ekind (Unit_Name) = E_Generic_Function
then
Set_Body_Needed_For_SAL (Unit_Name);
elsif Is_Subprogram (Unit_Name)
and then Nkind (Unit_Declaration_Node (Unit_Name)) =
N_Subprogram_Declaration
and then Has_Pragma_Inline (Unit_Name)
then
Set_Body_Needed_For_SAL (Unit_Name);
elsif Ekind (Unit_Name) = E_Subprogram_Body then
Check_Body_Needed_For_SAL
(Corresponding_Spec (Unit_Declaration_Node (Unit_Name)));
elsif Ekind (Unit_Name) = E_Package
and then Entity_Needs_Body (Unit_Name)
then
Set_Body_Needed_For_SAL (Unit_Name);
elsif Ekind (Unit_Name) = E_Package_Body
and then Nkind (Unit_Declaration_Node (Unit_Name)) = N_Package_Body
then
Check_Body_Needed_For_SAL
(Corresponding_Spec (Unit_Declaration_Node (Unit_Name)));
end if;
end Check_Body_Needed_For_SAL;
--------------------
-- Remove_Context --
--------------------
procedure Remove_Context (N : Node_Id) is
Lib_Unit : constant Node_Id := Unit (N);
begin
-- If this is a child unit, first remove the parent units.
if Is_Child_Spec (Lib_Unit) then
Remove_Parents (Lib_Unit);
end if;
Remove_Context_Clauses (N);
end Remove_Context;
----------------------------
-- Remove_Context_Clauses --
----------------------------
procedure Remove_Context_Clauses (N : Node_Id) is
Item : Node_Id;
Unit_Name : Entity_Id;
begin
-- Ada0Y (AI-50217): We remove the context clauses in two phases:
-- limited-views first and regular-views later (to maintain the
-- stack model).
-- First Phase: Remove limited_with context clauses
Item := First (Context_Items (N));
while Present (Item) loop
-- We are interested only in with clauses which got installed
-- on entry.
if Nkind (Item) = N_With_Clause
and then Limited_Present (Item)
and then Limited_View_Installed (Item)
then
Remove_Limited_With_Clause (Item);
end if;
Next (Item);
end loop;
-- Second Phase: Loop through context items and undo regular
-- with_clauses and use_clauses.
Item := First (Context_Items (N));
while Present (Item) loop
-- We are interested only in with clauses which got installed
-- on entry, as indicated by their Context_Installed flag set
if Nkind (Item) = N_With_Clause
and then Limited_Present (Item)
and then Limited_View_Installed (Item)
then
null;
elsif Nkind (Item) = N_With_Clause
and then Context_Installed (Item)
then
-- Remove items from one with'ed unit
Unit_Name := Entity (Name (Item));
Remove_Unit_From_Visibility (Unit_Name);
Set_Context_Installed (Item, False);
elsif Nkind (Item) = N_Use_Package_Clause then
End_Use_Package (Item);
elsif Nkind (Item) = N_Use_Type_Clause then
End_Use_Type (Item);
elsif Nkind (Item) = N_With_Type_Clause then
Remove_With_Type_Clause (Name (Item));
end if;
Next (Item);
end loop;
end Remove_Context_Clauses;
--------------------------------
-- Remove_Limited_With_Clause --
--------------------------------
procedure Remove_Limited_With_Clause (N : Node_Id) is
P_Unit : constant Entity_Id := Unit (Library_Unit (N));
P : Entity_Id := Defining_Unit_Name (Specification (P_Unit));
Lim_Elmt : Elmt_Id;
Lim_Typ : Entity_Id;
begin
if Nkind (P) = N_Defining_Program_Unit_Name then
-- Retrieve entity of Child package
P := Defining_Identifier (P);
end if;
if Debug_Flag_I then
Write_Str ("remove limited view of ");
Write_Name (Chars (P));
Write_Str (" from visibility");
Write_Eol;
end if;
-- Remove all shadow entities from visibility
Lim_Elmt := First_Elmt (Limited_Views (P));
while Present (Lim_Elmt) loop
Lim_Typ := Node (Lim_Elmt);
Unchain (Lim_Typ);
Next_Elmt (Lim_Elmt);
end loop;
-- Indicate that the limited view of the package is not installed
Set_From_With_Type (P, False);
Set_Limited_View_Installed (N, False);
-- If the exporting package has previously been analyzed, it
-- has appeared in the closure already and should be left alone.
-- Otherwise, remove package itself from visibility.
if not Analyzed (P_Unit) then
Unchain (P);
Set_First_Entity (P, Empty);
Set_Last_Entity (P, Empty);
Set_Ekind (P, E_Void);
Set_Scope (P, Empty);
Set_Is_Immediately_Visible (P, False);
else
-- Reinstall visible entities (entities removed from visibility in
-- Install_Limited_Withed to install the shadow entities).
declare
Ent : Entity_Id;
begin
Ent := First_Entity (P);
while Present (Ent) and then Ent /= First_Private_Entity (P) loop
-- Shadow entities have not been added to the list of
-- entities associated to the package spec. Therefore we
-- just have to re-chain all its visible entities.
if not Is_Class_Wide_Type (Ent) then
Set_Homonym (Ent, Current_Entity (Ent));
Set_Current_Entity (Ent);
if Debug_Flag_I then
Write_Str (" (homonym) chain ");
Write_Name (Chars (Ent));
Write_Eol;
end if;
end if;
Next_Entity (Ent);
end loop;
end;
end if;
end Remove_Limited_With_Clause;
--------------------
-- Remove_Parents --
--------------------
procedure Remove_Parents (Lib_Unit : Node_Id) is
P : Node_Id;
P_Name : Entity_Id;
E : Entity_Id;
Vis : constant Boolean :=
Scope_Stack.Table (Scope_Stack.Last).Previous_Visibility;
begin
if Is_Child_Spec (Lib_Unit) then
P := Unit (Parent_Spec (Lib_Unit));
P_Name := Get_Parent_Entity (P);
Remove_Context_Clauses (Parent_Spec (Lib_Unit));
End_Package_Scope (P_Name);
Set_Is_Immediately_Visible (P_Name, Vis);
-- Remove from visibility the siblings as well, which are directly
-- visible while the parent is in scope.
E := First_Entity (P_Name);
while Present (E) loop
if Is_Child_Unit (E) then
Set_Is_Immediately_Visible (E, False);
end if;
Next_Entity (E);
end loop;
Set_In_Package_Body (P_Name, False);
-- This is the recursive call to remove the context of any
-- higher level parent. This recursion ensures that all parents
-- are removed in the reverse order of their installation.
Remove_Parents (P);
end if;
end Remove_Parents;
-----------------------------
-- Remove_With_Type_Clause --
-----------------------------
procedure Remove_With_Type_Clause (Name : Node_Id) is
Typ : Entity_Id;
P : Entity_Id;
procedure Unchain (E : Entity_Id);
-- Remove entity from visibility list.
procedure Unchain (E : Entity_Id) is
Prev : Entity_Id;
begin
Prev := Current_Entity (E);
-- Package entity may appear is several with_type_clauses, and
-- may have been removed already.
if No (Prev) then
return;
elsif Prev = E then
Set_Name_Entity_Id (Chars (E), Homonym (E));
else
while Present (Prev)
and then Homonym (Prev) /= E
loop
Prev := Homonym (Prev);
end loop;
if Present (Prev) then
Set_Homonym (Prev, Homonym (E));
end if;
end if;
end Unchain;
-- Start of Remove_With_Type_Clause
begin
if Nkind (Name) = N_Selected_Component then
Typ := Entity (Selector_Name (Name));
if No (Typ) then -- error in declaration.
return;
end if;
else
return;
end if;
P := Scope (Typ);
-- If the exporting package has been analyzed, it has appeared in the
-- context already and should be left alone. Otherwise, remove from
-- visibility.
if not Analyzed (Unit_Declaration_Node (P)) then
Unchain (P);
Unchain (Typ);
Set_Is_Frozen (Typ, False);
end if;
if Ekind (Typ) = E_Record_Type then
Set_From_With_Type (Class_Wide_Type (Typ), False);
Set_From_With_Type (Typ, False);
end if;
Set_From_With_Type (P, False);
-- If P is a child unit, remove parents as well.
P := Scope (P);
while Present (P)
and then P /= Standard_Standard
loop
Set_From_With_Type (P, False);
if not Analyzed (Unit_Declaration_Node (P)) then
Unchain (P);
end if;
P := Scope (P);
end loop;
-- The back-end needs to know that an access type is imported, so it
-- does not need elaboration and can appear in a mutually recursive
-- record definition, so the imported flag on an access type is
-- preserved.
end Remove_With_Type_Clause;
---------------------------------
-- Remove_Unit_From_Visibility --
---------------------------------
procedure Remove_Unit_From_Visibility (Unit_Name : Entity_Id) is
P : constant Entity_Id := Scope (Unit_Name);
begin
if Debug_Flag_I then
Write_Str ("remove unit ");
Write_Name (Chars (Unit_Name));
Write_Str (" from visibility");
Write_Eol;
end if;
if P /= Standard_Standard then
Set_Is_Visible_Child_Unit (Unit_Name, False);
end if;
Set_Is_Potentially_Use_Visible (Unit_Name, False);
Set_Is_Immediately_Visible (Unit_Name, False);
end Remove_Unit_From_Visibility;
-------------
-- Unchain --
-------------
procedure Unchain (E : Entity_Id) is
Prev : Entity_Id;
begin
Prev := Current_Entity (E);