[Bug ada/121968] Inconsistent bug box from use clause in generic package parameter part

[ebotcazou at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121968

--- Comment #9 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
This is sufficient to fix the assertion failure:

--- a/gcc/ada/sem_dim.adb
+++ b/gcc/ada/sem_dim.adb
@@ -1273,7 +1273,9 @@ package body Sem_Dim is

          --  Get the expression from the component

-         if Nkind (Comp) = N_Component_Association then
+         if Nkind (Comp) in N_Component_Association
+                          | N_Iterated_Component_Association
+         then
             Expr := Expression (Comp);
          else
             Expr := Comp;