[gcc r13-1666] [Ada] Handle bodies-to-inline just like generic templates

[Pierre-Marie de Rodat <pmderodat@gcc.gnu.org>]

https://gcc.gnu.org/g:a714ca803cbf2f9e26ca214d7ddd7ed65bac2c26

commit r13-1666-ga714ca803cbf2f9e26ca214d7ddd7ed65bac2c26
Author: Piotr Trojanek <trojanek@adacore.com>
Date:   Wed Jul 6 09:37:15 2022 +0200

    [Ada] Handle bodies-to-inline just like generic templates
    
    Originally bodies-to-inline created for the frontend inlining were
    analyzed with expansion disabled. Then, to facilitate inlining in
    GNATprove mode, the analysis was changed to preanalysis.
    
    However, preanalysis in this context works badly for calls in prefix
    notation, because preanalysis assigns entities and types to nodes but
    doesn't convert calls from prefix to ordinary notation. When the
    body-to-inline is actually inlined, the (re)analysis of calls in prefix
    notation fails.
    
    The proper solution is rather to handle bodies-to-inline just like
    generic templates.
    
    From the user point of view, this patch fixes spurious errors both in
    GNATprove (which uses frontend inlining by default) and in GNAT (where
    frontend inlining is typically explicitly requested with -gnatN and
    pragma Inline_Always).
    
    gcc/ada/
    
            * inline.adb (Build_Body_To_Inline): Instead of manipulating the
            Full_Analysis flag, use the Inside_A_Generic flag (which is
            conveniently manipulated by Start_Generic/End_Generic, together
            with Expander_Active).
            * sem_attr.adb (Analyze_Attribute_Old_Result): Adapt comment and
            assertion to different flag that is set while building
            body-to-inline.

Diff:
---
 gcc/ada/inline.adb   | 12 ++----------
 gcc/ada/sem_attr.adb |  4 ++--
 2 files changed, 4 insertions(+), 12 deletions(-)

diff --git a/gcc/ada/inline.adb b/gcc/ada/inline.adb
index e0ff67a0649..e32df68152b 100644
--- a/gcc/ada/inline.adb
+++ b/gcc/ada/inline.adb
@@ -32,7 +32,6 @@ with Einfo.Entities; use Einfo.Entities;
 with Einfo.Utils;    use Einfo.Utils;
 with Elists;         use Elists;
 with Errout;         use Errout;
-with Expander;       use Expander;
 with Exp_Ch6;        use Exp_Ch6;
 with Exp_Ch7;        use Exp_Ch7;
 with Exp_Tss;        use Exp_Tss;
@@ -1107,7 +1106,6 @@ package body Inline is
 
    procedure Build_Body_To_Inline (N : Node_Id; Spec_Id : Entity_Id) is
       Decl            : constant Node_Id := Unit_Declaration_Node (Spec_Id);
-      Analysis_Status : constant Boolean := Full_Analysis;
       Original_Body   : Node_Id;
       Body_To_Analyze : Node_Id;
       Max_Size        : constant := 10;
@@ -1419,12 +1417,7 @@ package body Inline is
          Append (Body_To_Analyze, Declarations (N));
       end if;
 
-      --  The body to inline is preanalyzed. In GNATprove mode we must disable
-      --  full analysis as well so that light expansion does not take place
-      --  either, and name resolution is unaffected.
-
-      Expander_Mode_Save_And_Set (False);
-      Full_Analysis := False;
+      Start_Generic;
 
       Analyze (Body_To_Analyze);
       Push_Scope (Defining_Entity (Body_To_Analyze));
@@ -1432,8 +1425,7 @@ package body Inline is
       End_Scope;
       Remove (Body_To_Analyze);
 
-      Expander_Mode_Restore;
-      Full_Analysis := Analysis_Status;
+      End_Generic;
 
       --  Restore environment if previously saved
 
diff --git a/gcc/ada/sem_attr.adb b/gcc/ada/sem_attr.adb
index adeda43bd87..93bb6f42b6b 100644
--- a/gcc/ada/sem_attr.adb
+++ b/gcc/ada/sem_attr.adb
@@ -1508,9 +1508,9 @@ package body Sem_Attr is
            and then Chars (Spec_Id) = Name_uParent
            and then Chars (Scope (Spec_Id)) = Name_uPostconditions
          then
-            --  This situation occurs only when preanalyzing the inlined body
+            --  This situation occurs only when analyzing the body-to-inline
 
-            pragma Assert (not Full_Analysis);
+            pragma Assert (Inside_A_Generic);
 
             Spec_Id := Scope (Spec_Id);
             pragma Assert (Is_Inlined (Spec_Id));