https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65519
--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Eric Botcazou from comment #11)
> > I always forget how to force SJLJ EH on x86_64-linux for ada so I didn't
> > manage to reproduce the issue or check if the patch fixes it ...
>
> Yes, it does.
Verified. 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.
