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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S E M --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2021, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING3. If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
with Atree; use Atree;
with Debug; use Debug;
with Debug_A; use Debug_A;
with Einfo; use Einfo;
with Einfo.Entities; use Einfo.Entities;
with Einfo.Utils; use Einfo.Utils;
with Elists; use Elists;
with Exp_SPARK; use Exp_SPARK;
with Expander; use Expander;
with Ghost; use Ghost;
with Lib; use Lib;
with Lib.Load; use Lib.Load;
with Nlists; use Nlists;
with Output; use Output;
with Restrict; use Restrict;
with Sem_Attr; use Sem_Attr;
with Sem_Ch2; use Sem_Ch2;
with Sem_Ch3; use Sem_Ch3;
with Sem_Ch4; use Sem_Ch4;
with Sem_Ch5; use Sem_Ch5;
with Sem_Ch6; use Sem_Ch6;
with Sem_Ch7; use Sem_Ch7;
with Sem_Ch8; use Sem_Ch8;
with Sem_Ch9; use Sem_Ch9;
with Sem_Ch10; use Sem_Ch10;
with Sem_Ch11; use Sem_Ch11;
with Sem_Ch12; use Sem_Ch12;
with Sem_Ch13; use Sem_Ch13;
with Sem_Prag; use Sem_Prag;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Sinfo.Nodes; use Sinfo.Nodes;
with Sinfo.Utils; use Sinfo.Utils;
with Stand; use Stand;
with Stylesw; use Stylesw;
with Uintp; use Uintp;
with Uname; use Uname;
with Unchecked_Deallocation;
pragma Warnings (Off, Sem_Util);
-- Suppress warnings of unused with for Sem_Util (used only in asserts)
package body Sem is
Debug_Unit_Walk : Boolean renames Debug_Flag_Dot_WW;
-- Controls debugging printouts for Walk_Library_Items
Outer_Generic_Scope : Entity_Id := Empty;
-- Global reference to the outer scope that is generic. In a non-generic
-- context, it is empty. At the moment, it is only used for avoiding
-- freezing of external references in generics.
Comp_Unit_List : Elist_Id := No_Elist;
-- Used by Walk_Library_Items. This is a list of N_Compilation_Unit nodes
-- processed by Semantics, in an appropriate order. Initialized to
-- No_Elist, because it's too early to call New_Elmt_List; we will set it
-- to New_Elmt_List on first use.
generic
with procedure Action (Withed_Unit : Node_Id);
procedure Walk_Withs_Immediate (CU : Node_Id; Include_Limited : Boolean);
-- Walk all the with clauses of CU, and call Action for the with'ed unit.
-- Ignore limited withs, unless Include_Limited is True. CU must be an
-- N_Compilation_Unit.
generic
with procedure Action (Withed_Unit : Node_Id);
procedure Walk_Withs (CU : Node_Id; Include_Limited : Boolean);
-- Same as Walk_Withs_Immediate, but also include with clauses on subunits
-- of this unit, since they count as dependences on their parent library
-- item. CU must be an N_Compilation_Unit whose Unit is not an N_Subunit.
-------------
-- Analyze --
-------------
-- WARNING: This routine manages Ghost regions. Return statements must be
-- replaced by gotos which jump to the end of the routine and restore the
-- Ghost mode.
procedure Analyze (N : Node_Id) is
Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
-- Save the Ghost-related attributes to restore on exit
begin
Debug_A_Entry ("analyzing ", N);
-- Immediate return if already analyzed
if Analyzed (N) then
Debug_A_Exit ("analyzing ", N, " (done, analyzed already)");
return;
end if;
-- A declaration may be subject to pragma Ghost. Set the mode now to
-- ensure that any nodes generated during analysis and expansion are
-- marked as Ghost.
if Is_Declaration (N) then
Mark_And_Set_Ghost_Declaration (N);
end if;
-- Otherwise processing depends on the node kind
case Nkind (N) is
when N_Abort_Statement =>
Analyze_Abort_Statement (N);
when N_Abstract_Subprogram_Declaration =>
Analyze_Abstract_Subprogram_Declaration (N);
when N_Accept_Alternative =>
Analyze_Accept_Alternative (N);
when N_Accept_Statement =>
Analyze_Accept_Statement (N);
when N_Aggregate =>
Analyze_Aggregate (N);
when N_Allocator =>
Analyze_Allocator (N);
when N_And_Then =>
Analyze_Short_Circuit (N);
when N_Assignment_Statement =>
Analyze_Assignment (N);
when N_Asynchronous_Select =>
Analyze_Asynchronous_Select (N);
when N_At_Clause =>
Analyze_At_Clause (N);
when N_Attribute_Reference =>
Analyze_Attribute (N);
when N_Attribute_Definition_Clause =>
Analyze_Attribute_Definition_Clause (N);
when N_Block_Statement =>
Analyze_Block_Statement (N);
when N_Case_Expression =>
Analyze_Case_Expression (N);
when N_Case_Statement =>
Analyze_Case_Statement (N);
when N_Character_Literal =>
Analyze_Character_Literal (N);
when N_Code_Statement =>
Analyze_Code_Statement (N);
when N_Compilation_Unit =>
Analyze_Compilation_Unit (N);
when N_Component_Declaration =>
Analyze_Component_Declaration (N);
when N_Compound_Statement =>
Analyze_Compound_Statement (N);
when N_Conditional_Entry_Call =>
Analyze_Conditional_Entry_Call (N);
when N_Delay_Alternative =>
Analyze_Delay_Alternative (N);
when N_Delay_Relative_Statement =>
Analyze_Delay_Relative (N);
when N_Delay_Until_Statement =>
Analyze_Delay_Until (N);
when N_Delta_Aggregate =>
Analyze_Aggregate (N);
when N_Entry_Body =>
Analyze_Entry_Body (N);
when N_Entry_Body_Formal_Part =>
Analyze_Entry_Body_Formal_Part (N);
when N_Entry_Call_Alternative =>
Analyze_Entry_Call_Alternative (N);
when N_Entry_Declaration =>
Analyze_Entry_Declaration (N);
when N_Entry_Index_Specification =>
Analyze_Entry_Index_Specification (N);
when N_Enumeration_Representation_Clause =>
Analyze_Enumeration_Representation_Clause (N);
when N_Exception_Declaration =>
Analyze_Exception_Declaration (N);
when N_Exception_Renaming_Declaration =>
Analyze_Exception_Renaming (N);
when N_Exit_Statement =>
Analyze_Exit_Statement (N);
when N_Expanded_Name =>
Analyze_Expanded_Name (N);
when N_Explicit_Dereference =>
Analyze_Explicit_Dereference (N);
when N_Expression_Function =>
Analyze_Expression_Function (N);
when N_Expression_With_Actions =>
Analyze_Expression_With_Actions (N);
when N_Extended_Return_Statement =>
Analyze_Extended_Return_Statement (N);
when N_Extension_Aggregate =>
Analyze_Aggregate (N);
when N_Formal_Object_Declaration =>
Analyze_Formal_Object_Declaration (N);
when N_Formal_Package_Declaration =>
Analyze_Formal_Package_Declaration (N);
when N_Formal_Subprogram_Declaration =>
Analyze_Formal_Subprogram_Declaration (N);
when N_Formal_Type_Declaration =>
Analyze_Formal_Type_Declaration (N);
when N_Free_Statement =>
Analyze_Free_Statement (N);
when N_Freeze_Entity =>
Analyze_Freeze_Entity (N);
when N_Freeze_Generic_Entity =>
Analyze_Freeze_Generic_Entity (N);
when N_Full_Type_Declaration =>
Analyze_Full_Type_Declaration (N);
when N_Function_Call =>
Analyze_Function_Call (N);
when N_Function_Instantiation =>
Analyze_Function_Instantiation (N);
when N_Generic_Function_Renaming_Declaration =>
Analyze_Generic_Function_Renaming (N);
when N_Generic_Package_Declaration =>
Analyze_Generic_Package_Declaration (N);
when N_Generic_Package_Renaming_Declaration =>
Analyze_Generic_Package_Renaming (N);
when N_Generic_Procedure_Renaming_Declaration =>
Analyze_Generic_Procedure_Renaming (N);
when N_Generic_Subprogram_Declaration =>
Analyze_Generic_Subprogram_Declaration (N);
when N_Goto_Statement =>
Analyze_Goto_Statement (N);
when N_Goto_When_Statement =>
Analyze_Goto_When_Statement (N);
when N_Handled_Sequence_Of_Statements =>
Analyze_Handled_Statements (N);
when N_Identifier =>
Analyze_Identifier (N);
when N_If_Expression =>
Analyze_If_Expression (N);
when N_If_Statement =>
Analyze_If_Statement (N);
when N_Implicit_Label_Declaration =>
Analyze_Implicit_Label_Declaration (N);
when N_In =>
Analyze_Membership_Op (N);
when N_Incomplete_Type_Declaration =>
Analyze_Incomplete_Type_Decl (N);
when N_Indexed_Component =>
Analyze_Indexed_Component_Form (N);
when N_Integer_Literal =>
Analyze_Integer_Literal (N);
when N_Iterator_Specification =>
Analyze_Iterator_Specification (N);
when N_Itype_Reference =>
Analyze_Itype_Reference (N);
when N_Label =>
Analyze_Label (N);
when N_Loop_Parameter_Specification =>
Analyze_Loop_Parameter_Specification (N);
when N_Loop_Statement =>
Analyze_Loop_Statement (N);
when N_Not_In =>
Analyze_Membership_Op (N);
when N_Null =>
Analyze_Null (N);
when N_Null_Statement =>
Analyze_Null_Statement (N);
when N_Number_Declaration =>
Analyze_Number_Declaration (N);
when N_Object_Declaration =>
Analyze_Object_Declaration (N);
when N_Object_Renaming_Declaration =>
Analyze_Object_Renaming (N);
when N_Operator_Symbol =>
Analyze_Operator_Symbol (N);
when N_Op_Abs =>
Analyze_Unary_Op (N);
when N_Op_Add =>
Analyze_Arithmetic_Op (N);
when N_Op_And =>
Analyze_Logical_Op (N);
when N_Op_Concat =>
Analyze_Concatenation (N);
when N_Op_Divide =>
Analyze_Arithmetic_Op (N);
when N_Op_Eq =>
Analyze_Equality_Op (N);
when N_Op_Expon =>
Analyze_Arithmetic_Op (N);
when N_Op_Ge =>
Analyze_Comparison_Op (N);
when N_Op_Gt =>
Analyze_Comparison_Op (N);
when N_Op_Le =>
Analyze_Comparison_Op (N);
when N_Op_Lt =>
Analyze_Comparison_Op (N);
when N_Op_Minus =>
Analyze_Unary_Op (N);
when N_Op_Mod =>
Analyze_Mod (N);
when N_Op_Multiply =>
Analyze_Arithmetic_Op (N);
when N_Op_Ne =>
Analyze_Equality_Op (N);
when N_Op_Not =>
Analyze_Negation (N);
when N_Op_Or =>
Analyze_Logical_Op (N);
when N_Op_Plus =>
Analyze_Unary_Op (N);
when N_Op_Rem =>
Analyze_Arithmetic_Op (N);
when N_Op_Rotate_Left =>
Analyze_Arithmetic_Op (N);
when N_Op_Rotate_Right =>
Analyze_Arithmetic_Op (N);
when N_Op_Shift_Left =>
Analyze_Arithmetic_Op (N);
when N_Op_Shift_Right =>
Analyze_Arithmetic_Op (N);
when N_Op_Shift_Right_Arithmetic =>
Analyze_Arithmetic_Op (N);
when N_Op_Subtract =>
Analyze_Arithmetic_Op (N);
when N_Op_Xor =>
Analyze_Logical_Op (N);
when N_Or_Else =>
Analyze_Short_Circuit (N);
when N_Others_Choice =>
Analyze_Others_Choice (N);
when N_Package_Body =>
Analyze_Package_Body (N);
when N_Package_Body_Stub =>
Analyze_Package_Body_Stub (N);
when N_Package_Declaration =>
Analyze_Package_Declaration (N);
when N_Package_Instantiation =>
Analyze_Package_Instantiation (N);
when N_Package_Renaming_Declaration =>
Analyze_Package_Renaming (N);
when N_Package_Specification =>
Analyze_Package_Specification (N);
when N_Parameter_Association =>
Analyze_Parameter_Association (N);
when N_Pragma =>
Analyze_Pragma (N);
when N_Private_Extension_Declaration =>
Analyze_Private_Extension_Declaration (N);
when N_Private_Type_Declaration =>
Analyze_Private_Type_Declaration (N);
when N_Procedure_Call_Statement =>
Analyze_Procedure_Call (N);
when N_Procedure_Instantiation =>
Analyze_Procedure_Instantiation (N);
when N_Protected_Body =>
Analyze_Protected_Body (N);
when N_Protected_Body_Stub =>
Analyze_Protected_Body_Stub (N);
when N_Protected_Definition =>
Analyze_Protected_Definition (N);
when N_Protected_Type_Declaration =>
Analyze_Protected_Type_Declaration (N);
when N_Qualified_Expression =>
Analyze_Qualified_Expression (N);
when N_Quantified_Expression =>
Analyze_Quantified_Expression (N);
when N_Raise_Expression =>
Analyze_Raise_Expression (N);
when N_Raise_Statement =>
Analyze_Raise_Statement (N);
when N_Raise_When_Statement =>
Analyze_Raise_When_Statement (N);
when N_Raise_xxx_Error =>
Analyze_Raise_xxx_Error (N);
when N_Range =>
Analyze_Range (N);
when N_Range_Constraint =>
Analyze_Range (Range_Expression (N));
when N_Real_Literal =>
Analyze_Real_Literal (N);
when N_Record_Representation_Clause =>
Analyze_Record_Representation_Clause (N);
when N_Reference =>
Analyze_Reference (N);
when N_Requeue_Statement =>
Analyze_Requeue (N);
when N_Return_When_Statement =>
Analyze_Return_When_Statement (N);
when N_Simple_Return_Statement =>
Analyze_Simple_Return_Statement (N);
when N_Selected_Component =>
Find_Selected_Component (N);
-- ??? why not Analyze_Selected_Component, needs comments
when N_Selective_Accept =>
Analyze_Selective_Accept (N);
when N_Single_Protected_Declaration =>
Analyze_Single_Protected_Declaration (N);
when N_Single_Task_Declaration =>
Analyze_Single_Task_Declaration (N);
when N_Slice =>
Analyze_Slice (N);
when N_String_Literal =>
Analyze_String_Literal (N);
when N_Subprogram_Body =>
Analyze_Subprogram_Body (N);
when N_Subprogram_Body_Stub =>
Analyze_Subprogram_Body_Stub (N);
when N_Subprogram_Declaration =>
Analyze_Subprogram_Declaration (N);
when N_Subprogram_Renaming_Declaration =>
Analyze_Subprogram_Renaming (N);
when N_Subtype_Declaration =>
Analyze_Subtype_Declaration (N);
when N_Subtype_Indication =>
Analyze_Subtype_Indication (N);
when N_Subunit =>
Analyze_Subunit (N);
when N_Target_Name =>
Analyze_Target_Name (N);
when N_Task_Body =>
Analyze_Task_Body (N);
when N_Task_Body_Stub =>
Analyze_Task_Body_Stub (N);
when N_Task_Definition =>
Analyze_Task_Definition (N);
when N_Task_Type_Declaration =>
Analyze_Task_Type_Declaration (N);
when N_Terminate_Alternative =>
Analyze_Terminate_Alternative (N);
when N_Timed_Entry_Call =>
Analyze_Timed_Entry_Call (N);
when N_Triggering_Alternative =>
Analyze_Triggering_Alternative (N);
when N_Type_Conversion =>
Analyze_Type_Conversion (N);
when N_Unchecked_Expression =>
Analyze_Unchecked_Expression (N);
when N_Unchecked_Type_Conversion =>
Analyze_Unchecked_Type_Conversion (N);
when N_Use_Package_Clause =>
Analyze_Use_Package (N);
when N_Use_Type_Clause =>
Analyze_Use_Type (N);
when N_Validate_Unchecked_Conversion =>
null;
when N_Variant_Part =>
Analyze_Variant_Part (N);
when N_With_Clause =>
Analyze_With_Clause (N);
-- A call to analyze a marker is ignored because the node does not
-- have any static and run-time semantics.
when N_Call_Marker
| N_Variable_Reference_Marker
=>
null;
-- A call to analyze the Empty node is an error, but most likely it
-- is an error caused by an attempt to analyze a malformed piece of
-- tree caused by some other error, so if there have been any other
-- errors, we just ignore it, otherwise it is a real internal error
-- which we complain about.
-- We must also consider the case of call to a runtime function that
-- is not available in the configurable runtime.
when N_Empty =>
pragma Assert (Serious_Errors_Detected /= 0
or else Configurable_Run_Time_Violations /= 0);
null;
-- A call to analyze the error node is simply ignored, to avoid
-- causing cascaded errors (happens of course only in error cases)
-- Disable expansion in case it is still enabled, to prevent other
-- subsequent compiler glitches.
when N_Error =>
Expander_Mode_Save_And_Set (False);
null;
-- Push/Pop nodes normally don't come through an analyze call. An
-- exception is the dummy ones bracketing a subprogram body. In any
-- case there is nothing to be done to analyze such nodes.
when N_Push_Pop_xxx_Label =>
null;
-- SCIL nodes don't need analysis because they are decorated when
-- they are built. They are added to the tree by Insert_Actions and
-- the call to analyze them is generated when the full list is
-- analyzed.
when N_SCIL_Dispatch_Table_Tag_Init
| N_SCIL_Dispatching_Call
| N_SCIL_Membership_Test
=>
null;
-- A quantified expression with a missing "all" or "some" qualifier
-- looks identical to an iterated component association. By language
-- definition, the latter must be present within array aggregates. If
-- this is not the case, then the iterated component association is
-- really an illegal quantified expression. Diagnose this scenario.
when N_Iterated_Component_Association =>
Diagnose_Iterated_Component_Association (N);
when N_Iterated_Element_Association =>
null; -- May require a more precise error if misplaced.
-- For the remaining node types, we generate compiler abort, because
-- these nodes are always analyzed within the Sem_Chn routines and
-- there should never be a case of making a call to the main Analyze
-- routine for these node kinds. For example, an N_Access_Definition
-- node appears only in the context of a type declaration, and is
-- processed by the analyze routine for type declarations.
when N_Abortable_Part
| N_Access_Definition
| N_Access_Function_Definition
| N_Access_Procedure_Definition
| N_Access_To_Object_Definition
| N_Aspect_Specification
| N_Case_Expression_Alternative
| N_Case_Statement_Alternative
| N_Compilation_Unit_Aux
| N_Component_Association
| N_Component_Clause
| N_Component_Definition
| N_Component_List
| N_Constrained_Array_Definition
| N_Contract
| N_Decimal_Fixed_Point_Definition
| N_Defining_Character_Literal
| N_Defining_Identifier
| N_Defining_Operator_Symbol
| N_Defining_Program_Unit_Name
| N_Delta_Constraint
| N_Derived_Type_Definition
| N_Designator
| N_Digits_Constraint
| N_Discriminant_Association
| N_Discriminant_Specification
| N_Elsif_Part
| N_Entry_Call_Statement
| N_Enumeration_Type_Definition
| N_Exception_Handler
| N_Floating_Point_Definition
| N_Formal_Decimal_Fixed_Point_Definition
| N_Formal_Derived_Type_Definition
| N_Formal_Discrete_Type_Definition
| N_Formal_Floating_Point_Definition
| N_Formal_Modular_Type_Definition
| N_Formal_Ordinary_Fixed_Point_Definition
| N_Formal_Private_Type_Definition
| N_Formal_Incomplete_Type_Definition
| N_Formal_Signed_Integer_Type_Definition
| N_Function_Specification
| N_Generic_Association
| N_Index_Or_Discriminant_Constraint
| N_Iteration_Scheme
| N_Mod_Clause
| N_Modular_Type_Definition
| N_Ordinary_Fixed_Point_Definition
| N_Parameter_Specification
| N_Pragma_Argument_Association
| N_Procedure_Specification
| N_Real_Range_Specification
| N_Record_Definition
| N_Signed_Integer_Type_Definition
| N_Unconstrained_Array_Definition
| N_Unused_At_End
| N_Unused_At_Start
| N_Variant
=>
raise Program_Error;
end case;
Debug_A_Exit ("analyzing ", N, " (done)");
-- Mark relevant use-type and use-package clauses as effective
-- preferring the original node over the analyzed one in the case that
-- constant folding has occurred and removed references that need to be
-- examined. Also, if the node in question is overloaded then this is
-- deferred until resolution.
declare
Operat : Node_Id := Empty;
begin
-- Attempt to obtain a checkable operator node
if Nkind (Original_Node (N)) in N_Op then
Operat := Original_Node (N);
elsif Nkind (N) in N_Op then
Operat := N;
end if;
-- Mark the operator
if Present (Operat)
and then Present (Entity (Operat))
and then not Is_Overloaded (Operat)
then
Mark_Use_Clauses (Operat);
end if;
end;
-- Now that we have analyzed the node, we call the expander to perform
-- possible expansion. We skip this for subexpressions, because we don't
-- have the type yet, and the expander will need to know the type before
-- it can do its job. For subexpression nodes, the call to the expander
-- happens in Sem_Res.Resolve. A special exception is Raise_xxx_Error,
-- which can appear in a statement context, and needs expanding now in
-- the case (distinguished by Etype, as documented in Sinfo).
-- The Analyzed flag is also set at this point for non-subexpression
-- nodes (in the case of subexpression nodes, we can't set the flag yet,
-- since resolution and expansion have not yet been completed). Note
-- that for N_Raise_xxx_Error we have to distinguish the expression
-- case from the statement case.
if Nkind (N) not in N_Subexpr
or else (Nkind (N) in N_Raise_xxx_Error
and then Etype (N) = Standard_Void_Type)
then
Expand (N);
-- Replace a reference to a renaming with the renamed object for SPARK.
-- In general this modification is performed by Expand_SPARK, however
-- certain constructs may not reach the resolution or expansion phase
-- and thus remain unchanged. The replacement is not performed when the
-- construct is overloaded as resolution must first take place. This is
-- also not done when analyzing a generic to preserve the original tree
-- and because the reference may become overloaded in the instance.
elsif GNATprove_Mode
and then Nkind (N) in N_Expanded_Name | N_Identifier
and then not Is_Overloaded (N)
and then not Inside_A_Generic
then
Expand_SPARK_Potential_Renaming (N);
end if;
Restore_Ghost_Region (Saved_GM, Saved_IGR);
end Analyze;
-- Version with check(s) suppressed
procedure Analyze (N : Node_Id; Suppress : Check_Id) is
begin
if Suppress = All_Checks then
declare
Svs : constant Suppress_Array := Scope_Suppress.Suppress;
begin
Scope_Suppress.Suppress := (others => True);
Analyze (N);
Scope_Suppress.Suppress := Svs;
end;
else
declare
Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
begin
Scope_Suppress.Suppress (Suppress) := True;
Analyze (N);
Scope_Suppress.Suppress (Suppress) := Svg;
end;
end if;
end Analyze;
------------------
-- Analyze_List --
------------------
procedure Analyze_List (L : List_Id) is
Node : Node_Id;
begin
Node := First (L);
while Present (Node) loop
Analyze (Node);
Next (Node);
end loop;
end Analyze_List;
-- Version with check(s) suppressed
procedure Analyze_List (L : List_Id; Suppress : Check_Id) is
begin
if Suppress = All_Checks then
declare
Svs : constant Suppress_Array := Scope_Suppress.Suppress;
begin
Scope_Suppress.Suppress := (others => True);
Analyze_List (L);
Scope_Suppress.Suppress := Svs;
end;
else
declare
Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
begin
Scope_Suppress.Suppress (Suppress) := True;
Analyze_List (L);
Scope_Suppress.Suppress (Suppress) := Svg;
end;
end if;
end Analyze_List;
--------------------------
-- Copy_Suppress_Status --
--------------------------
procedure Copy_Suppress_Status
(C : Check_Id;
From : Entity_Id;
To : Entity_Id)
is
Found : Boolean;
pragma Warnings (Off, Found);
procedure Search_Stack
(Top : Suppress_Stack_Entry_Ptr;
Found : out Boolean);
-- Search given suppress stack for matching entry for entity. If found
-- then set Checks_May_Be_Suppressed on To, and push an appropriate
-- entry for To onto the local suppress stack.
------------------
-- Search_Stack --
------------------
procedure Search_Stack
(Top : Suppress_Stack_Entry_Ptr;
Found : out Boolean)
is
Ptr : Suppress_Stack_Entry_Ptr;
begin
Ptr := Top;
while Ptr /= null loop
if Ptr.Entity = From
and then (Ptr.Check = All_Checks or else Ptr.Check = C)
then
if Ptr.Suppress then
Set_Checks_May_Be_Suppressed (To, True);
Push_Local_Suppress_Stack_Entry
(Entity => To,
Check => C,
Suppress => True);
Found := True;
return;
end if;
end if;
Ptr := Ptr.Prev;
end loop;
Found := False;
return;
end Search_Stack;
-- Start of processing for Copy_Suppress_Status
begin
if not Checks_May_Be_Suppressed (From) then
return;
end if;
-- First search the global entity suppress table for a matching entry.
-- We also search this in reverse order so that if there are multiple
-- pragmas for the same entity, the last one applies.
Search_Stack (Global_Suppress_Stack_Top, Found);
if Found then
return;
end if;
-- Now search the local entity suppress stack, we search this in
-- reverse order so that we get the innermost entry that applies to
-- this case if there are nested entries. Note that for the purpose
-- of this procedure we are ONLY looking for entries corresponding
-- to a two-argument Suppress, where the second argument matches From.
Search_Stack (Local_Suppress_Stack_Top, Found);
end Copy_Suppress_Status;
-------------------------
-- Enter_Generic_Scope --
-------------------------
procedure Enter_Generic_Scope (S : Entity_Id) is
begin
if No (Outer_Generic_Scope) then
Outer_Generic_Scope := S;
end if;
end Enter_Generic_Scope;
------------------------
-- Exit_Generic_Scope --
------------------------
procedure Exit_Generic_Scope (S : Entity_Id) is
begin
if S = Outer_Generic_Scope then
Outer_Generic_Scope := Empty;
end if;
end Exit_Generic_Scope;
-----------------------
-- Explicit_Suppress --
-----------------------
function Explicit_Suppress (E : Entity_Id; C : Check_Id) return Boolean is
Ptr : Suppress_Stack_Entry_Ptr;
begin
if not Checks_May_Be_Suppressed (E) then
return False;
else
Ptr := Global_Suppress_Stack_Top;
while Ptr /= null loop
if Ptr.Entity = E
and then (Ptr.Check = All_Checks or else Ptr.Check = C)
then
return Ptr.Suppress;
end if;
Ptr := Ptr.Prev;
end loop;
end if;
return False;
end Explicit_Suppress;
-----------------------------
-- External_Ref_In_Generic --
-----------------------------
function External_Ref_In_Generic (E : Entity_Id) return Boolean is
Scop : Entity_Id;
begin
-- Entity is global if defined outside of current outer_generic_scope:
-- Either the entity has a smaller depth that the outer generic, or it
-- is in a different compilation unit, or it is defined within a unit
-- in the same compilation, that is not within the outer_generic.
if No (Outer_Generic_Scope) then
return False;
elsif Scope_Depth (Scope (E)) < Scope_Depth (Outer_Generic_Scope)
or else not In_Same_Source_Unit (E, Outer_Generic_Scope)
then
return True;
else
Scop := Scope (E);
while Present (Scop) loop
if Scop = Outer_Generic_Scope then
return False;
elsif Scope_Depth (Scop) < Scope_Depth (Outer_Generic_Scope) then
return True;
else
Scop := Scope (Scop);
end if;
end loop;
return True;
end if;
end External_Ref_In_Generic;
----------------
-- Initialize --
----------------
procedure Initialize is
Next : Suppress_Stack_Entry_Ptr;
procedure Free is new Unchecked_Deallocation
(Suppress_Stack_Entry, Suppress_Stack_Entry_Ptr);
begin
-- Free any global suppress stack entries from a previous invocation
-- of the compiler (in the normal case this loop does nothing).
while Suppress_Stack_Entries /= null loop
Next := Suppress_Stack_Entries.Next;
Free (Suppress_Stack_Entries);
Suppress_Stack_Entries := Next;
end loop;
Local_Suppress_Stack_Top := null;
Global_Suppress_Stack_Top := null;
-- Clear scope stack, and reset global variables
Scope_Stack.Init;
Unloaded_Subunits := False;
end Initialize;
------------------------------
-- Insert_After_And_Analyze --
------------------------------
procedure Insert_After_And_Analyze (N : Node_Id; M : Node_Id) is
Node : Node_Id;
begin
if Present (M) then
-- If we are not at the end of the list, then the easiest
-- coding is simply to insert before our successor.
if Present (Next (N)) then
Insert_Before_And_Analyze (Next (N), M);
-- Case of inserting at the end of the list
else
-- Capture the Node_Id of the node to be inserted. This Node_Id
-- will still be the same after the insert operation.
Node := M;
Insert_After (N, M);
-- Now just analyze from the inserted node to the end of
-- the new list (note that this properly handles the case
-- where any of the analyze calls result in the insertion of
-- nodes after the analyzed node, expecting analysis).
while Present (Node) loop
Analyze (Node);
Mark_Rewrite_Insertion (Node);
Next (Node);
end loop;
end if;
end if;
end Insert_After_And_Analyze;
-- Version with check(s) suppressed
procedure Insert_After_And_Analyze
(N : Node_Id;
M : Node_Id;
Suppress : Check_Id)
is
begin
if Suppress = All_Checks then
declare
Svs : constant Suppress_Array := Scope_Suppress.Suppress;
begin
Scope_Suppress.Suppress := (others => True);
Insert_After_And_Analyze (N, M);
Scope_Suppress.Suppress := Svs;
end;
else
declare
Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
begin
Scope_Suppress.Suppress (Suppress) := True;
Insert_After_And_Analyze (N, M);
Scope_Suppress.Suppress (Suppress) := Svg;
end;
end if;
end Insert_After_And_Analyze;
-------------------------------
-- Insert_Before_And_Analyze --
-------------------------------
procedure Insert_Before_And_Analyze (N : Node_Id; M : Node_Id) is
Node : Node_Id;
begin
if Present (M) then
-- Capture the Node_Id of the first list node to be inserted.
-- This will still be the first node after the insert operation,
-- since Insert_List_After does not modify the Node_Id values.
Node := M;
Insert_Before (N, M);
-- The insertion does not change the Id's of any of the nodes in
-- the list, and they are still linked, so we can simply loop from
-- the original first node until we meet the node before which the
-- insertion is occurring. Note that this properly handles the case
-- where any of the analyzed nodes insert nodes after themselves,
-- expecting them to get analyzed.
while Node /= N loop
Analyze (Node);
Mark_Rewrite_Insertion (Node);
Next (Node);
end loop;
end if;
end Insert_Before_And_Analyze;
-- Version with check(s) suppressed
procedure Insert_Before_And_Analyze
(N : Node_Id;
M : Node_Id;
Suppress : Check_Id)
is
begin
if Suppress = All_Checks then
declare
Svs : constant Suppress_Array := Scope_Suppress.Suppress;
begin
Scope_Suppress.Suppress := (others => True);
Insert_Before_And_Analyze (N, M);
Scope_Suppress.Suppress := Svs;
end;
else
declare
Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
begin
Scope_Suppress.Suppress (Suppress) := True;
Insert_Before_And_Analyze (N, M);
Scope_Suppress.Suppress (Suppress) := Svg;
end;
end if;
end Insert_Before_And_Analyze;
--------------------------------------------
-- Insert_Before_First_Source_Declaration --
--------------------------------------------
procedure Insert_Before_First_Source_Declaration
(Stmt : Node_Id;
Decls : List_Id)
is
Decl : Node_Id;
begin
-- Inspect the declarations of the related subprogram body looking for
-- the first source declaration.
pragma Assert (Present (Decls));
Decl := First (Decls);
while Present (Decl) loop
if Comes_From_Source (Decl) then
Insert_Before (Decl, Stmt);
return;
end if;
Next (Decl);
end loop;
-- If we get there, then the subprogram body lacks any source
-- declarations. The body of _Postconditions now acts as the
-- last declaration.
Append (Stmt, Decls);
end Insert_Before_First_Source_Declaration;
-----------------------------------
-- Insert_List_After_And_Analyze --
-----------------------------------
procedure Insert_List_After_And_Analyze (N : Node_Id; L : List_Id) is
After : constant Node_Id := Next (N);
Node : Node_Id;
begin
if Is_Non_Empty_List (L) then
-- Capture the Node_Id of the first list node to be inserted.
-- This will still be the first node after the insert operation,
-- since Insert_List_After does not modify the Node_Id values.
Node := First (L);
Insert_List_After (N, L);
-- Now just analyze from the original first node until we get to the
-- successor of the original insertion point (which may be Empty if
-- the insertion point was at the end of the list). Note that this
-- properly handles the case where any of the analyze calls result in
-- the insertion of nodes after the analyzed node (possibly calling
-- this routine recursively).
while Node /= After loop
Analyze (Node);
Mark_Rewrite_Insertion (Node);
Next (Node);
end loop;
end if;
end Insert_List_After_And_Analyze;
------------------------------------
-- Insert_List_Before_And_Analyze --
------------------------------------
procedure Insert_List_Before_And_Analyze (N : Node_Id; L : List_Id) is
Node : Node_Id;
begin
if Is_Non_Empty_List (L) then
-- Capture the Node_Id of the first list node to be inserted. This
-- will still be the first node after the insert operation, since
-- Insert_List_After does not modify the Node_Id values.
Node := First (L);
Insert_List_Before (N, L);
-- The insertion does not change the Id's of any of the nodes in
-- the list, and they are still linked, so we can simply loop from
-- the original first node until we meet the node before which the
-- insertion is occurring. Note that this properly handles the case
-- where any of the analyzed nodes insert nodes after themselves,
-- expecting them to get analyzed.
while Node /= N loop
Analyze (Node);
Mark_Rewrite_Insertion (Node);
Next (Node);
end loop;
end if;
end Insert_List_Before_And_Analyze;
----------
-- Lock --
----------
procedure Lock is
begin
Scope_Stack.Release;
Scope_Stack.Locked := True;
end Lock;
------------------------
-- Preanalysis_Active --
------------------------
function Preanalysis_Active return Boolean is
begin
return not Full_Analysis and not Expander_Active;
end Preanalysis_Active;
----------------
-- Preanalyze --
----------------
procedure Preanalyze (N : Node_Id) is
Save_Full_Analysis : constant Boolean := Full_Analysis;
begin
Full_Analysis := False;
Expander_Mode_Save_And_Set (False);
Analyze (N);
Expander_Mode_Restore;
Full_Analysis := Save_Full_Analysis;
end Preanalyze;
--------------------------------------
-- Push_Global_Suppress_Stack_Entry --
--------------------------------------
procedure Push_Global_Suppress_Stack_Entry
(Entity : Entity_Id;
Check : Check_Id;
Suppress : Boolean)
is
begin
Global_Suppress_Stack_Top :=
new Suppress_Stack_Entry'
(Entity => Entity,
Check => Check,
Suppress => Suppress,
Prev => Global_Suppress_Stack_Top,
Next => Suppress_Stack_Entries);
Suppress_Stack_Entries := Global_Suppress_Stack_Top;
return;
end Push_Global_Suppress_Stack_Entry;
-------------------------------------
-- Push_Local_Suppress_Stack_Entry --
-------------------------------------
procedure Push_Local_Suppress_Stack_Entry
(Entity : Entity_Id;
Check : Check_Id;
Suppress : Boolean)
is
begin
Local_Suppress_Stack_Top :=
new Suppress_Stack_Entry'
(Entity => Entity,
Check => Check,
Suppress => Suppress,
Prev => Local_Suppress_Stack_Top,
Next => Suppress_Stack_Entries);
Suppress_Stack_Entries := Local_Suppress_Stack_Top;
return;
end Push_Local_Suppress_Stack_Entry;
---------------
-- Semantics --
---------------
procedure Semantics (Comp_Unit : Node_Id) is
procedure Do_Analyze;
-- Perform the analysis of the compilation unit
----------------
-- Do_Analyze --
----------------
-- WARNING: This routine manages Ghost regions. Return statements must
-- be replaced by gotos which jump to the end of the routine and restore
-- the Ghost mode.
procedure Do_Analyze is
Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
Saved_ISMP : constant Boolean :=
Ignore_SPARK_Mode_Pragmas_In_Instance;
-- Save Ghost and SPARK mode-related data to restore on exit
-- Generally style checks are preserved across compilations, with
-- one exception: s-oscons.ads, which allows arbitrary long lines
-- unconditionally, and has no restore mechanism, because it is
-- intended as a lowest-level Pure package.
Saved_ML : constant Int := Style_Max_Line_Length;
Saved_CML : constant Boolean := Style_Check_Max_Line_Length;
List : Elist_Id;
begin
List := Save_Scope_Stack;
Push_Scope (Standard_Standard);
-- Set up a clean environment before analyzing
Install_Ghost_Region (None, Empty);
Ignore_SPARK_Mode_Pragmas_In_Instance := False;
Outer_Generic_Scope := Empty;
Scope_Suppress := Suppress_Options;
Scope_Stack.Table
(Scope_Stack.Last).Component_Alignment_Default :=
Configuration_Component_Alignment;
Scope_Stack.Table
(Scope_Stack.Last).Is_Active_Stack_Base := True;
-- Now analyze the top level compilation unit node
Analyze (Comp_Unit);
-- Check for scope mismatch on exit from compilation
pragma Assert (Current_Scope = Standard_Standard
or else Comp_Unit = Cunit (Main_Unit));
-- Then pop entry for Standard, and pop implicit types
Pop_Scope;
Restore_Scope_Stack (List);
Style_Max_Line_Length := Saved_ML;
Style_Check_Max_Line_Length := Saved_CML;
Restore_Ghost_Region (Saved_GM, Saved_IGR);
Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP;
end Do_Analyze;
-- Local variables
-- The following locations save the corresponding global flags and
-- variables so that they can be restored on completion. This is needed
-- so that calls to Rtsfind start with the proper default values for
-- these variables, and also that such calls do not disturb the settings
-- for units being analyzed at a higher level.
S_Current_Sem_Unit : constant Unit_Number_Type := Current_Sem_Unit;
S_Full_Analysis : constant Boolean := Full_Analysis;
S_GNAT_Mode : constant Boolean := GNAT_Mode;
S_Global_Dis_Names : constant Boolean := Global_Discard_Names;
S_In_Assertion_Expr : constant Nat := In_Assertion_Expr;
S_In_Declare_Expr : constant Nat := In_Declare_Expr;
S_In_Default_Expr : constant Boolean := In_Default_Expr;
S_In_Spec_Expr : constant Boolean := In_Spec_Expression;
S_Inside_A_Generic : constant Boolean := Inside_A_Generic;
S_Outer_Gen_Scope : constant Entity_Id := Outer_Generic_Scope;
S_Style_Check : constant Boolean := Style_Check;
Already_Analyzed : constant Boolean := Analyzed (Comp_Unit);
Curunit : constant Unit_Number_Type := Get_Cunit_Unit_Number (Comp_Unit);
-- New value of Current_Sem_Unit
Generic_Main : constant Boolean :=
Nkind (Unit (Cunit (Main_Unit))) in N_Generic_Declaration;
-- If the main unit is generic, every compiled unit, including its
-- context, is compiled with expansion disabled.
Is_Main_Unit_Or_Main_Unit_Spec : constant Boolean :=
Curunit = Main_Unit
or else
(Nkind (Unit (Cunit (Main_Unit))) = N_Package_Body
and then Library_Unit (Cunit (Main_Unit)) = Cunit (Curunit));
-- Configuration flags have special settings when compiling a predefined
-- file as a main unit. This applies to its spec as well.
Ext_Main_Source_Unit : constant Boolean :=
In_Extended_Main_Source_Unit (Comp_Unit);
-- Determine if unit is in extended main source unit
Save_Config_Attrs : Config_Switches_Type;
-- Variable used to save values of config switches while we analyze the
-- new unit, to be restored on exit for proper recursive behavior.
Save_Cunit_Restrictions : Save_Cunit_Boolean_Restrictions;
-- Used to save non-partition wide restrictions before processing new
-- unit. All with'ed units are analyzed with config restrictions reset
-- and we need to restore these saved values at the end.
Save_Preanalysis_Counter : constant Nat :=
Inside_Preanalysis_Without_Freezing;
-- Saves the preanalysis nesting-level counter; required since we may
-- need to analyze a unit as a consequence of the preanalysis of an
-- expression without freezing (and the loaded unit must be fully
-- analyzed).
-- Start of processing for Semantics
begin
Inside_Preanalysis_Without_Freezing := 0;
if Debug_Unit_Walk then
if Already_Analyzed then
Write_Str ("(done)");
end if;
Write_Unit_Info
(Get_Cunit_Unit_Number (Comp_Unit),
Unit (Comp_Unit),
Prefix => "--> ");
Indent;
end if;
Compiler_State := Analyzing;
Current_Sem_Unit := Curunit;
-- Compile predefined units with GNAT_Mode set to True, to properly
-- process the categorization stuff. However, do not set GNAT_Mode
-- to True for the renamings units (Text_IO, IO_Exceptions, Direct_IO,
-- Sequential_IO) as this would prevent pragma Extend_System from being
-- taken into account, for example when Text_IO is renaming DEC.Text_IO.
if Is_Predefined_Unit (Current_Sem_Unit)
and then not Is_Predefined_Renaming (Current_Sem_Unit)
then
GNAT_Mode := True;
end if;
-- For generic main, never do expansion
if Generic_Main then
Expander_Mode_Save_And_Set (False);
-- Non generic case
else
Expander_Mode_Save_And_Set
-- Turn on expansion if generating code
(Operating_Mode = Generate_Code
-- Or if special debug flag -gnatdx is set
or else Debug_Flag_X
-- Or if in configuration run-time mode. We do this so we get
-- error messages about missing entities in the run-time even
-- if we are compiling in -gnatc (no code generation) mode.
-- Similar processing applies to No_Run_Time_Mode. However,
-- don't do this if debug flag -gnatd.Z is set or when we are
-- compiling a separate unit (this is to handle a situation
-- where this new processing causes trouble).
or else
((Configurable_Run_Time_Mode or No_Run_Time_Mode)
and then not Debug_Flag_Dot_ZZ
and then Nkind (Unit (Cunit (Main_Unit))) /= N_Subunit));
end if;
Full_Analysis := True;
Inside_A_Generic := False;
In_Assertion_Expr := 0;
In_Declare_Expr := 0;
In_Default_Expr := False;
In_Spec_Expression := False;
Set_Comes_From_Source_Default (False);
-- Save current config switches and reset then appropriately
Save_Config_Attrs := Save_Config_Switches;
Set_Config_Switches
(Is_Internal_Unit (Current_Sem_Unit),
Is_Main_Unit_Or_Main_Unit_Spec);
-- Save current non-partition-wide restrictions
Save_Cunit_Restrictions := Cunit_Boolean_Restrictions_Save;
-- For unit in main extended unit, we reset the configuration values
-- for the non-partition-wide restrictions. For other units reset them.
if Ext_Main_Source_Unit then
Restore_Config_Cunit_Boolean_Restrictions;
else
Reset_Cunit_Boolean_Restrictions;
end if;
-- Turn off style checks for unit that is not in the extended main
-- source unit. This improves processing efficiency for such units
-- (for which we don't want style checks anyway, and where they will
-- get suppressed), and is definitely needed to stop some style checks
-- from invading the run-time units (e.g. overriding checks).
if not Ext_Main_Source_Unit then
Style_Check := False;
-- If this is part of the extended main source unit, set style check
-- mode to match the style check mode of the main source unit itself.
else
Style_Check := Style_Check_Main;
end if;
-- Only do analysis of unit that has not already been analyzed
if not Analyzed (Comp_Unit) then
Initialize_Version (Current_Sem_Unit);
-- Do analysis, and then append the compilation unit onto the
-- Comp_Unit_List, if appropriate. This is done after analysis,
-- so if this unit depends on some others, they have already been
-- appended. We ignore bodies, except for the main unit itself, and
-- for subprogram bodies that act as specs. We have also to guard
-- against ill-formed subunits that have an improper context.
Do_Analyze;
if Present (Comp_Unit)
and then Nkind (Unit (Comp_Unit)) in N_Proper_Body
and then (Nkind (Unit (Comp_Unit)) /= N_Subprogram_Body
or else not Acts_As_Spec (Comp_Unit))
and then not Ext_Main_Source_Unit
then
null;
else
Append_New_Elmt (Comp_Unit, To => Comp_Unit_List);
if Debug_Unit_Walk then
Write_Str ("Appending ");
Write_Unit_Info
(Get_Cunit_Unit_Number (Comp_Unit), Unit (Comp_Unit));
end if;
end if;
end if;
-- Save indication of dynamic elaboration checks for ALI file
Set_Dynamic_Elab (Current_Sem_Unit, Dynamic_Elaboration_Checks);
-- Restore settings of saved switches to entry values
Current_Sem_Unit := S_Current_Sem_Unit;
Full_Analysis := S_Full_Analysis;
Global_Discard_Names := S_Global_Dis_Names;
GNAT_Mode := S_GNAT_Mode;
In_Assertion_Expr := S_In_Assertion_Expr;
In_Declare_Expr := S_In_Declare_Expr;
In_Default_Expr := S_In_Default_Expr;
In_Spec_Expression := S_In_Spec_Expr;
Inside_A_Generic := S_Inside_A_Generic;
Outer_Generic_Scope := S_Outer_Gen_Scope;
Style_Check := S_Style_Check;
Restore_Config_Switches (Save_Config_Attrs);
-- Deal with restore of restrictions
Cunit_Boolean_Restrictions_Restore (Save_Cunit_Restrictions);
Expander_Mode_Restore;
if Debug_Unit_Walk then
Outdent;
if Already_Analyzed then
Write_Str ("(done)");
end if;
Write_Unit_Info
(Get_Cunit_Unit_Number (Comp_Unit),
Unit (Comp_Unit),
Prefix => "<-- ");
end if;
Inside_Preanalysis_Without_Freezing := Save_Preanalysis_Counter;
end Semantics;
--------
-- ss --
--------
function ss (Index : Int) return Scope_Stack_Entry is
begin
return Scope_Stack.Table (Index);
end ss;
---------
-- sst --
---------
function sst return Scope_Stack_Entry is
begin
return ss (Scope_Stack.Last);
end sst;
------------
-- Unlock --
------------
procedure Unlock is
begin
Scope_Stack.Locked := False;
end Unlock;
------------------------
-- Walk_Library_Items --
------------------------
procedure Walk_Library_Items is
type Unit_Number_Set is array (Main_Unit .. Last_Unit) of Boolean;
pragma Pack (Unit_Number_Set);
Main_CU : constant Node_Id := Cunit (Main_Unit);
Spec_CU : Node_Id := Empty;
Seen, Done : Unit_Number_Set := (others => False);
-- Seen (X) is True after we have seen unit X in the walk. This is used
-- to prevent processing the same unit more than once. Done (X) is True
-- after we have fully processed X, and is used only for debugging
-- printouts and assertions.
Do_Main : Boolean := False;
-- Flag to delay processing the main body until after all other units.
-- This is needed because the spec of the main unit may appear in the
-- context of some other unit. We do not want this to force processing
-- of the main body before all other units have been processed.
--
-- Another circularity pattern occurs when the main unit is a child unit
-- and the body of an ancestor has a with-clause of the main unit or on
-- one of its children. In both cases the body in question has a with-
-- clause on the main unit, and must be excluded from the traversal. In
-- some convoluted cases this may lead to a CodePeer error because the
-- spec of a subprogram declared in an instance within the parent will
-- not be seen in the main unit.
function Depends_On_Main (CU : Node_Id) return Boolean;
-- The body of a unit that is withed by the spec of the main unit may in
-- turn have a with_clause on that spec. In that case do not traverse
-- the body, to prevent loops. It can also happen that the main body has
-- a with_clause on a child, which of course has an implicit with on its
-- parent. It's OK to traverse the child body if the main spec has been
-- processed, otherwise we also have a circularity to avoid.
procedure Do_Action (CU : Node_Id; Item : Node_Id);
-- Calls Action, with some validity checks
procedure Do_Unit_And_Dependents (CU : Node_Id; Item : Node_Id);
-- Calls Do_Action, first on the units with'ed by this one, then on
-- this unit. If it's an instance body, do the spec first. If it is
-- an instance spec, do the body last.
procedure Do_Withed_Unit (Withed_Unit : Node_Id);
-- Apply Do_Unit_And_Dependents to a unit in a context clause
procedure Process_Bodies_In_Context (Comp : Node_Id);
-- The main unit and its spec may depend on bodies that contain generics
-- that are instantiated in them. Iterate through the corresponding
-- contexts before processing main (spec/body) itself, to process bodies
-- that may be present, together with their context. The spec of main
-- is processed wherever it appears in the list of units, while the body
-- is processed as the last unit in the list.
---------------------
-- Depends_On_Main --
---------------------
function Depends_On_Main (CU : Node_Id) return Boolean is
CL : Node_Id;
MCU : constant Node_Id := Unit (Main_CU);
begin
-- Problem does not arise with main subprograms
if Nkind (MCU) not in N_Package_Body | N_Package_Declaration then
return False;
end if;
CL := First (Context_Items (CU));
while Present (CL) loop
if Nkind (CL) = N_With_Clause
and then Library_Unit (CL) = Main_CU
and then not Done (Get_Cunit_Unit_Number (Library_Unit (CL)))
then
return True;
end if;
Next (CL);
end loop;
return False;
end Depends_On_Main;
---------------
-- Do_Action --
---------------
procedure Do_Action (CU : Node_Id; Item : Node_Id) is
begin
-- This calls Action at the end. All the preceding code is just
-- assertions and debugging output.
pragma Assert (No (CU) or else Nkind (CU) = N_Compilation_Unit);
case Nkind (Item) is
when N_Generic_Function_Renaming_Declaration
| N_Generic_Package_Declaration
| N_Generic_Package_Renaming_Declaration
| N_Generic_Procedure_Renaming_Declaration
| N_Generic_Subprogram_Declaration
| N_Package_Declaration
| N_Package_Renaming_Declaration
| N_Subprogram_Declaration
| N_Subprogram_Renaming_Declaration
=>
-- Specs are OK
null;
when N_Package_Body =>
-- Package bodies are processed separately if the main unit
-- depends on them.
null;
when N_Subprogram_Body =>
-- A subprogram body must be the main unit
pragma Assert (Acts_As_Spec (CU) or else CU = Main_CU);
null;
when N_Function_Instantiation
| N_Package_Instantiation
| N_Procedure_Instantiation
=>
-- Can only happen if some generic body (needed for gnat2scil
-- traversal, but not by GNAT) is not available, ignore.
null;
-- All other cases cannot happen
when N_Subunit =>
pragma Assert (False, "subunit");
null;
when N_Null_Statement =>
-- Do not call Action for an ignored ghost unit
pragma Assert (Is_Ignored_Ghost_Node (Original_Node (Item)));
return;
when others =>
pragma Assert (False);
null;
end case;
if Present (CU) then
pragma Assert (Item /= Stand.Standard_Package_Node);
pragma Assert (Item = Unit (CU));
declare
Unit_Num : constant Unit_Number_Type :=
Get_Cunit_Unit_Number (CU);
procedure Assert_Done (Withed_Unit : Node_Id);
-- Assert Withed_Unit is already Done, unless it's a body. It
-- might seem strange for a with_clause to refer to a body, but
-- this happens in the case of a generic instantiation, which
-- gets transformed into the instance body (and the instance
-- spec is also created). With clauses pointing to the
-- instantiation end up pointing to the instance body.
-----------------
-- Assert_Done --
-----------------
procedure Assert_Done (Withed_Unit : Node_Id) is
begin
if Withed_Unit /= Main_CU
and then not Done (Get_Cunit_Unit_Number (Withed_Unit))
then
-- N_Null_Statement will happen in case of a ghost unit
-- which gets rewritten.
if Nkind (Unit (Withed_Unit)) not in
N_Generic_Package_Declaration |
N_Package_Body |
N_Package_Renaming_Declaration |
N_Subprogram_Body |
N_Null_Statement
then
Write_Unit_Name
(Unit_Name (Get_Cunit_Unit_Number (Withed_Unit)));
Write_Str (" not yet walked!");
if Get_Cunit_Unit_Number (Withed_Unit) = Unit_Num then
Write_Str (" (self-ref)");
end if;
Write_Eol;
pragma Assert (False);
end if;
end if;
end Assert_Done;
procedure Assert_Withed_Units_Done is
new Walk_Withs (Assert_Done);
begin
if Debug_Unit_Walk then
Write_Unit_Info (Unit_Num, Item, Withs => True);
end if;
-- Main unit should come last, except in the case where we
-- skipped System_Aux_Id, in which case we missed the things it
-- depends on, and in the case of parent bodies if present.
pragma Assert
(not Done (Main_Unit)
or else Present (System_Aux_Id)
or else Nkind (Item) = N_Package_Body);
-- We shouldn't do the same thing twice
pragma Assert (not Done (Unit_Num));
-- Everything we depend upon should already be done
pragma Debug
(Assert_Withed_Units_Done (CU, Include_Limited => False));
end;
else
-- Must be Standard, which has no entry in the units table
pragma Assert (Item = Stand.Standard_Package_Node);
if Debug_Unit_Walk then
Write_Line ("Standard");
end if;
end if;
Action (Item);
end Do_Action;
--------------------
-- Do_Withed_Unit --
--------------------
procedure Do_Withed_Unit (Withed_Unit : Node_Id) is
begin
Do_Unit_And_Dependents (Withed_Unit, Unit (Withed_Unit));
-- If the unit in the with_clause is a generic instance, the clause
-- now denotes the instance body. Traverse the corresponding spec
-- because there may be no other dependence that will force the
-- traversal of its own context.
if Nkind (Unit (Withed_Unit)) = N_Package_Body
and then Is_Generic_Instance
(Defining_Entity (Unit (Library_Unit (Withed_Unit))))
then
Do_Withed_Unit (Library_Unit (Withed_Unit));
end if;
end Do_Withed_Unit;
----------------------------
-- Do_Unit_And_Dependents --
----------------------------
procedure Do_Unit_And_Dependents (CU : Node_Id; Item : Node_Id) is
Unit_Num : constant Unit_Number_Type := Get_Cunit_Unit_Number (CU);
Child : Node_Id;
Body_U : Unit_Number_Type;
Parent_CU : Node_Id;
procedure Do_Withed_Units is new Walk_Withs (Do_Withed_Unit);
begin
if not Seen (Unit_Num) then
-- Process the with clauses
Do_Withed_Units (CU, Include_Limited => False);
-- Process the unit if it is a spec or the main unit, if it
-- has no previous spec or we have done all other units.
if Nkind (Item) not in N_Package_Body | N_Subprogram_Body
or else Acts_As_Spec (CU)
then
if CU = Main_CU and then not Do_Main then
Seen (Unit_Num) := False;
else
Seen (Unit_Num) := True;
if CU = Library_Unit (Main_CU) then
Process_Bodies_In_Context (CU);
-- If main is a child unit, examine parent unit contexts
-- to see if they include instantiated units. Also, if
-- the parent itself is an instance, process its body
-- because it may contain subprograms that are called
-- in the main unit.
if Is_Child_Unit (Cunit_Entity (Main_Unit)) then
Child := Cunit_Entity (Main_Unit);
while Is_Child_Unit (Child) loop
Parent_CU :=
Cunit
(Get_Cunit_Entity_Unit_Number (Scope (Child)));
Process_Bodies_In_Context (Parent_CU);
if Nkind (Unit (Parent_CU)) = N_Package_Body
and then
Nkind (Original_Node (Unit (Parent_CU)))
= N_Package_Instantiation
and then
not Seen (Get_Cunit_Unit_Number (Parent_CU))
then
Body_U := Get_Cunit_Unit_Number (Parent_CU);
Seen (Body_U) := True;
Do_Action (Parent_CU, Unit (Parent_CU));
Done (Body_U) := True;
end if;
Child := Scope (Child);
end loop;
end if;
end if;
Do_Action (CU, Item);
Done (Unit_Num) := True;
end if;
end if;
end if;
end Do_Unit_And_Dependents;
-------------------------------
-- Process_Bodies_In_Context --
-------------------------------
procedure Process_Bodies_In_Context (Comp : Node_Id) is
Body_CU : Node_Id;
Body_U : Unit_Number_Type;
Clause : Node_Id;
Spec : Node_Id;
procedure Do_Withed_Units is new Walk_Withs (Do_Withed_Unit);
-- Start of processing for Process_Bodies_In_Context
begin
Clause := First (Context_Items (Comp));
while Present (Clause) loop
if Nkind (Clause) = N_With_Clause then
Spec := Library_Unit (Clause);
Body_CU := Library_Unit (Spec);
-- If we are processing the spec of the main unit, load bodies
-- only if the with_clause indicates that it forced the loading
-- of the body for a generic instantiation. Note that bodies of
-- parents that are instances have been loaded already.
if Present (Body_CU)
and then Body_CU /= Main_CU
and then Nkind (Unit (Body_CU)) /= N_Subprogram_Body
and then Nkind (Unit (Comp)) /= N_Package_Declaration
then
Body_U := Get_Cunit_Unit_Number (Body_CU);
if not Seen (Body_U)
and then not Depends_On_Main (Body_CU)
then
Seen (Body_U) := True;
Do_Withed_Units (Body_CU, Include_Limited => False);
Do_Action (Body_CU, Unit (Body_CU));
Done (Body_U) := True;
end if;
end if;
end if;
Next (Clause);
end loop;
end Process_Bodies_In_Context;
-- Local Declarations
Cur : Elmt_Id;
-- Start of processing for Walk_Library_Items
begin
if Debug_Unit_Walk then
Write_Line ("Walk_Library_Items:");
Indent;
end if;
-- Do Standard first, then walk the Comp_Unit_List
Do_Action (Empty, Standard_Package_Node);
-- First place the context of all instance bodies on the corresponding
-- spec, because it may be needed to analyze the code at the place of
-- the instantiation.
Cur := First_Elmt (Comp_Unit_List);
while Present (Cur) loop
declare
CU : constant Node_Id := Node (Cur);
N : constant Node_Id := Unit (CU);
begin
if Nkind (N) = N_Package_Body
and then Is_Generic_Instance (Defining_Entity (N))
then
Append_List
(Context_Items (CU), Context_Items (Library_Unit (CU)));
end if;
Next_Elmt (Cur);
end;
end loop;
-- Now traverse compilation units (specs) in order
Cur := First_Elmt (Comp_Unit_List);
while Present (Cur) loop
declare
CU : constant Node_Id := Node (Cur);
N : constant Node_Id := Unit (CU);
Par : Entity_Id;
begin
pragma Assert (Nkind (CU) = N_Compilation_Unit);
case Nkind (N) is
-- If it is a subprogram body, process it if it has no
-- separate spec.
-- If it's a package body, ignore it, unless it is a body
-- created for an instance that is the main unit. In the case
-- of subprograms, the body is the wrapper package. In case of
-- a package, the original file carries the body, and the spec
-- appears as a later entry in the units list.
-- Otherwise bodies appear in the list only because of inlining
-- or instantiations, and they are processed only if relevant.
-- The flag Withed_Body on a context clause indicates that a
-- unit contains an instantiation that may be needed later,
-- and therefore the body that contains the generic body (and
-- its context) must be traversed immediately after the
-- corresponding spec (see Do_Unit_And_Dependents).
-- The main unit itself is processed separately after all other
-- specs, and relevant bodies are examined in Process_Main.
when N_Subprogram_Body =>
if Acts_As_Spec (N) then
Do_Unit_And_Dependents (CU, N);
end if;
when N_Package_Body =>
if CU = Main_CU
and then Nkind (Original_Node (Unit (Main_CU))) in
N_Generic_Instantiation
and then Present (Library_Unit (Main_CU))
then
Do_Unit_And_Dependents
(Library_Unit (Main_CU),
Unit (Library_Unit (Main_CU)));
end if;
-- It is a spec, process it, and the units it depends on,
-- unless it is a descendant of the main unit. This can happen
-- when the body of a parent depends on some other descendant.
when N_Null_Statement =>
-- Ignore an ignored ghost unit
pragma Assert (Is_Ignored_Ghost_Node (Original_Node (N)));
null;
when others =>
-- Skip spec of main unit for now, we want to process it
-- after all other specs.
if Nkind (Unit (CU)) = N_Package_Declaration
and then Library_Unit (CU) = Main_CU
and then CU /= Main_CU
then
Spec_CU := CU;
else
Par := Scope (Defining_Entity (Unit (CU)));
if Is_Child_Unit (Defining_Entity (Unit (CU))) then
while Present (Par)
and then Par /= Standard_Standard
and then Par /= Cunit_Entity (Main_Unit)
loop
Par := Scope (Par);
end loop;
end if;
if Par /= Cunit_Entity (Main_Unit) then
Do_Unit_And_Dependents (CU, N);
end if;
end if;
end case;
end;
Next_Elmt (Cur);
end loop;
-- Now process main package spec if skipped
if Present (Spec_CU) then
Do_Unit_And_Dependents (Spec_CU, Unit (Spec_CU));
end if;
-- Now process package bodies on which main depends, followed by bodies
-- of parents, if present, and finally main itself.
if not Done (Main_Unit) then
Do_Main := True;
Process_Main : declare
Parent_CU : Node_Id;
Body_CU : Node_Id;
Body_U : Unit_Number_Type;
Child : Entity_Id;
function Is_Subunit_Of_Main (U : Node_Id) return Boolean;
-- If the main unit has subunits, their context may include
-- bodies that are needed in the body of main. We must examine
-- the context of the subunits, which are otherwise not made
-- explicit in the main unit.
------------------------
-- Is_Subunit_Of_Main --
------------------------
function Is_Subunit_Of_Main (U : Node_Id) return Boolean is
Lib : Node_Id;
begin
if Present (U) and then Nkind (Unit (U)) = N_Subunit then
Lib := Library_Unit (U);
return Lib = Main_CU or else Is_Subunit_Of_Main (Lib);
else
return False;
end if;
end Is_Subunit_Of_Main;
-- Start of processing for Process_Main
begin
Process_Bodies_In_Context (Main_CU);
for Unit_Num in Done'Range loop
if Is_Subunit_Of_Main (Cunit (Unit_Num)) then
Process_Bodies_In_Context (Cunit (Unit_Num));
end if;
end loop;
-- If the main unit is a child unit, parent bodies may be present
-- because they export instances or inlined subprograms. Check for
-- presence of these, which are not present in context clauses.
-- Note that if the parents are instances, their bodies have been
-- processed before the main spec, because they may be needed
-- therein, so the following loop only affects non-instances.
if Is_Child_Unit (Cunit_Entity (Main_Unit)) then
Child := Cunit_Entity (Main_Unit);
while Is_Child_Unit (Child) loop
Parent_CU :=
Cunit (Get_Cunit_Entity_Unit_Number (Scope (Child)));
Body_CU := Library_Unit (Parent_CU);
if Present (Body_CU)
and then not Seen (Get_Cunit_Unit_Number (Body_CU))
and then not Depends_On_Main (Body_CU)
then
Body_U := Get_Cunit_Unit_Number (Body_CU);
Seen (Body_U) := True;
Do_Action (Body_CU, Unit (Body_CU));
Done (Body_U) := True;
end if;
Child := Scope (Child);
end loop;
end if;
Do_Action (Main_CU, Unit (Main_CU));
Done (Main_Unit) := True;
end Process_Main;
end if;
if Debug_Unit_Walk then
if Done /= (Done'Range => True) then
Write_Eol;
Write_Line ("Ignored units:");
Indent;
for Unit_Num in Done'Range loop
if not Done (Unit_Num) then
-- Units with configuration pragmas (.ads files) have empty
-- compilation-unit nodes; skip printing info about them.
if Present (Cunit (Unit_Num)) then
Write_Unit_Info
(Unit_Num, Unit (Cunit (Unit_Num)), Withs => True);
end if;
end if;
end loop;
Outdent;
end if;
end if;
pragma Assert (Done (Main_Unit));
if Debug_Unit_Walk then
Outdent;
Write_Line ("end Walk_Library_Items.");
end if;
end Walk_Library_Items;
----------------
-- Walk_Withs --
----------------
procedure Walk_Withs (CU : Node_Id; Include_Limited : Boolean) is
pragma Assert (Nkind (CU) = N_Compilation_Unit);
pragma Assert (Nkind (Unit (CU)) /= N_Subunit);
procedure Walk_Immediate is new Walk_Withs_Immediate (Action);
begin
-- First walk the withs immediately on the library item
Walk_Immediate (CU, Include_Limited);
-- For a body, we must also check for any subunits which belong to it
-- and which have context clauses of their own, since these with'ed
-- units are part of its own dependencies.
if Nkind (Unit (CU)) in N_Unit_Body then
for S in Main_Unit .. Last_Unit loop
-- We are only interested in subunits. For preproc. data and def.
-- files, Cunit is Empty, so we need to test that first.
if Cunit (S) /= Empty
and then Nkind (Unit (Cunit (S))) = N_Subunit
then
declare
Pnode : Node_Id;
begin
Pnode := Library_Unit (Cunit (S));
-- In -gnatc mode, the errors in the subunits will not have
-- been recorded, but the analysis of the subunit may have
-- failed, so just quit.
if No (Pnode) then
exit;
end if;
-- Find ultimate parent of the subunit
while Nkind (Unit (Pnode)) = N_Subunit loop
Pnode := Library_Unit (Pnode);
end loop;
-- See if it belongs to current unit, and if so, include its
-- with_clauses. Do not process main unit prematurely.
if Pnode = CU and then CU /= Cunit (Main_Unit) then
Walk_Immediate (Cunit (S), Include_Limited);
end if;
end;
end if;
end loop;
end if;
end Walk_Withs;
--------------------------
-- Walk_Withs_Immediate --
--------------------------
procedure Walk_Withs_Immediate (CU : Node_Id; Include_Limited : Boolean) is
pragma Assert (Nkind (CU) = N_Compilation_Unit);
Context_Item : Node_Id;
Lib_Unit : Node_Id;
begin
Context_Item := First (Context_Items (CU));
while Present (Context_Item) loop
if Nkind (Context_Item) = N_With_Clause
and then (Include_Limited
or else not Limited_Present (Context_Item))
then
Lib_Unit := Library_Unit (Context_Item);
Action (Lib_Unit);
end if;
Next (Context_Item);
end loop;
end Walk_Withs_Immediate;
end Sem;