https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65519
--- Comment #13 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> I'll add
>
> Index: gcc/testsuite/gnat.dg/opt48.adb
> ===================================================================
> --- gcc/testsuite/gnat.dg/opt48.adb (revision 0)
> +++ gcc/testsuite/gnat.dg/opt48.adb (working copy)
> @@ -0,0 +1,11 @@
> +-- { dg-do compile }
> +-- { dg-options "-O2" }
> +
> +with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;
> +with Interfaces; use Interfaces;
> +
> +package Opt48 is
> +
> + type Arr is array (Unsigned_32 range <>) of Unbounded_String;
> +
> +end P;
>
> given that passes in my bootstrap/test run.
Careful, it's a package spec only so it needs to have .ads extension and placed
in gnat.dg/specs.
