[gcc r13-3682] ada: Fix couple of issues with arrays indexed by enumeration type

[Marc Poulhi?s <dkm@gcc.gnu.org>]

https://gcc.gnu.org/g:4eac8834f9fb703ea04d3d3992a497182f4f86f0

commit r13-3682-g4eac8834f9fb703ea04d3d3992a497182f4f86f0
Author: Eric Botcazou <ebotcazou@adacore.com>
Date:   Wed Oct 12 12:41:49 2022 +0200

    ada: Fix couple of issues with arrays indexed by enumeration type
    
    The first one is that Remove_Warning_Messages reinstates the Original_Node
    of an N_Raise_Constraint_Error node in the tree for no clear reasons, and
    the Original_Node may contain constructs whose expansion has been stopped
    when the Constraint_Error was asserted, eventually causing gigi to stop.
    
    The second one is that a path in Build_Array_Aggr_Code.Gen_Loop does not
    copy the loop bounds, unlike other paths, thus triggering a sharing issue.
    
    gcc/ada/
    
            * errout.adb (Remove_Warning_Messages.Check_For_Warning): Do not
            reinstate the Original_Node in the tree.
            * exp_aggr.adb (Build_Array_Aggr_Code.Gen_Loop): Copy the bounds
            on all paths.

Diff:
---
 gcc/ada/errout.adb   | 16 +++-------------
 gcc/ada/exp_aggr.adb |  4 ++--
 2 files changed, 5 insertions(+), 15 deletions(-)

diff --git a/gcc/ada/errout.adb b/gcc/ada/errout.adb
index 85931552970..5730a543ee1 100644
--- a/gcc/ada/errout.adb
+++ b/gcc/ada/errout.adb
@@ -3383,23 +3383,13 @@ package body Errout is
             E := Errors.Table (E).Next;
          end loop;
 
+         --  Warnings may have been posted on subexpressions of original tree
+
          if Nkind (N) = N_Raise_Constraint_Error
            and then Is_Rewrite_Substitution (N)
            and then No (Condition (N))
          then
-            --  Warnings may have been posted on subexpressions of the original
-            --  tree. We place the original node back on the tree to remove
-            --  those warnings, whose sloc do not match those of any node in
-            --  the current tree. Given that we are in unreachable code, this
-            --  modification to the tree is harmless.
-
-            if Is_List_Member (N) then
-               Set_Condition (N, Original_Node (N));
-               Check_All_Warnings (Condition (N));
-            else
-               Rewrite (N, Original_Node (N));
-               Check_All_Warnings (N);
-            end if;
+            Check_All_Warnings (Original_Node (N));
          end if;
 
          return OK;
diff --git a/gcc/ada/exp_aggr.adb b/gcc/ada/exp_aggr.adb
index 185705544e9..dde49d1e289 100644
--- a/gcc/ada/exp_aggr.adb
+++ b/gcc/ada/exp_aggr.adb
@@ -2058,7 +2058,7 @@ package body Exp_Aggr is
          --  to do that if we already have the base type at hand.
 
          if Etype (L) = Index_Base then
-            L_L := L;
+            L_L := New_Copy_Tree (L);
          else
             L_L :=
               Make_Qualified_Expression (Loc,
@@ -2067,7 +2067,7 @@ package body Exp_Aggr is
          end if;
 
          if Etype (H) = Index_Base then
-            L_H := H;
+            L_H := New_Copy_Tree (H);
          else
             L_H :=
               Make_Qualified_Expression (Loc,