[gcc r12-6457] [Ada] Fix incomplete debug info for derived packed array type

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

https://gcc.gnu.org/g:4217466a87672372ec0d5e0affafd33c06a35574

commit r12-6457-g4217466a87672372ec0d5e0affafd33c06a35574
Author: Eric Botcazou <ebotcazou@adacore.com>
Date:   Tue Jan 4 13:39:45 2022 +0100

    [Ada] Fix incomplete debug info for derived packed array type
    
    gcc/ada/
    
            * sem_ch3.adb (Analyze_Subtype_Declaration): In the case of an array
            copy Packed_Array_Impl_Type manually here.
            (Copy_Array_Subtype_Attributes): Do not copy it here.

Diff:
---
 gcc/ada/sem_ch3.adb | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/gcc/ada/sem_ch3.adb b/gcc/ada/sem_ch3.adb
index 06b8cc4a6aa..2e207c16e23 100644
--- a/gcc/ada/sem_ch3.adb
+++ b/gcc/ada/sem_ch3.adb
@@ -5512,6 +5512,7 @@ package body Sem_Ch3 is
             when Array_Kind =>
                Mutate_Ekind                  (Id, E_Array_Subtype);
                Copy_Array_Subtype_Attributes (Id, T);
+               Set_Packed_Array_Impl_Type    (Id, Packed_Array_Impl_Type (T));
 
             when Decimal_Fixed_Point_Kind =>
                Mutate_Ekind             (Id, E_Decimal_Fixed_Point_Subtype);
@@ -14972,6 +14973,9 @@ package body Sem_Ch3 is
    -- Copy_Array_Subtype_Attributes --
    -----------------------------------
 
+   --  Note that we used to copy Packed_Array_Impl_Type too here, but we now
+   --  let it be recreated during freezing for the sake of better debug info.
+
    procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
    begin
       Set_Size_Info (T1, T2);
@@ -14989,7 +14993,6 @@ package body Sem_Ch3 is
       Set_Convention              (T1, Convention              (T2));
       Set_Is_Limited_Composite    (T1, Is_Limited_Composite    (T2));
       Set_Is_Private_Composite    (T1, Is_Private_Composite    (T2));
-      Set_Packed_Array_Impl_Type  (T1, Packed_Array_Impl_Type  (T2));
    end Copy_Array_Subtype_Attributes;
 
    -----------------------------------