[gcc r11-6018] [Ada] Incorrect accessibility level on type in formal package

[gcc r11-6018] [Ada] Incorrect accessibility level on type in formal package

[Pierre-Marie de Rodat]

https://gcc.gnu.org/g:7e7d99bfa23c7d84ba48b9131e2134cf4049d791

commit r11-6018-g7e7d99bfa23c7d84ba48b9131e2134cf4049d791
Author: Justin Squirek <squirek@adacore.com>
Date:   Fri Nov 20 08:11:12 2020 -0500

    [Ada] Incorrect accessibility level on type in formal package
    
    gcc/ada/
    
            * sem_util.adb, sem_util.ads (In_Generic_Formal_Package):
            Created to identify type declarations occurring within generic
            formal packages.
            * sem_res.adb (Resolve_Allocator): Add condition to avoid
            emitting an error for allocators when the type being allocated
            is class-wide and from a generic formal package.

Diff:
---
 gcc/ada/sem_res.adb  |  7 +++++--
 gcc/ada/sem_util.adb | 22 ++++++++++++++++++++++
 gcc/ada/sem_util.ads |  3 +++
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/gcc/ada/sem_res.adb b/gcc/ada/sem_res.adb
index 659db865f93..05ebf20ca26 100644
--- a/gcc/ada/sem_res.adb
+++ b/gcc/ada/sem_res.adb
@@ -5451,9 +5451,12 @@ package body Sem_Res is
 
                --  Do not apply Ada 2005 accessibility checks on a class-wide
                --  allocator if the type given in the allocator is a formal
-               --  type. A run-time check will be performed in the instance.
+               --  type or within a formal package. A run-time check will be
+               --  performed in the instance.
 
-               elsif not Is_Generic_Type (Exp_Typ) then
+               elsif not Is_Generic_Type (Exp_Typ)
+                 and then not In_Generic_Formal_Package (Exp_Typ)
+               then
                   Error_Msg_N
                     ("type in allocator has deeper level than designated "
                      & "class-wide type", E);
diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 72dbc6868af..30d4457ea31 100644
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -13827,6 +13827,28 @@ package body Sem_Util is
           and then Assertion_Expression_Pragma (Get_Pragma_Id (Prag));
    end In_Assertion_Expression_Pragma;
 
+   -------------------------------
+   -- In_Generic_Formal_Package --
+   -------------------------------
+
+   function In_Generic_Formal_Package (E : Entity_Id) return Boolean is
+      Par : Node_Id;
+
+   begin
+      Par := Parent (E);
+      while Present (Par) loop
+         if Nkind (Par) = N_Formal_Package_Declaration
+           or else Nkind (Original_Node (Par)) = N_Formal_Package_Declaration
+         then
+            return True;
+         end if;
+
+         Par := Parent (Par);
+      end loop;
+
+      return False;
+   end In_Generic_Formal_Package;
+
    ----------------------
    -- In_Generic_Scope --
    ----------------------
diff --git a/gcc/ada/sem_util.ads b/gcc/ada/sem_util.ads
index b2af43a7406..2e913594bc0 100644
--- a/gcc/ada/sem_util.ads
+++ b/gcc/ada/sem_util.ads
@@ -1538,6 +1538,9 @@ package Sem_Util is
    --  Returns True if node N appears within a pragma that acts as an assertion
    --  expression. See Sem_Prag for the list of qualifying pragmas.
 
+   function In_Generic_Formal_Package (E : Entity_Id) return Boolean;
+   --  Returns True if entity E is inside a generic formal package
+
    function In_Generic_Scope (E : Entity_Id) return Boolean;
    --  Returns True if entity E is inside a generic scope