[Bug c++/126752] [16/17 Regression] ICE in build_vec_init when initializing an array member of an aggregate

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126752

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
The fix will be simple:
--- gcc/cp/init.cc.jj   2026-08-07 22:59:40.789404047 +0200
+++ gcc/cp/init.cc      2026-08-12 00:16:22.913503966 +0200
@@ -5365,7 +5365,7 @@ build_vec_init (tree base, tree maxindex
              && !vec_safe_is_empty (*cleanup_flags))
            {
              auto l = (*cleanup_flags)->last ();
-             gcc_assert (TREE_PURPOSE (l) == iterator);
+             gcc_assert (TREE_PURPOSE (l) == rval);
              (*cleanup_flags)->pop ();
            }
          tree const_init = build_constructor (atype, const_vec);
plus testcase, but I wonder why this code no longer triggers on
initlist-array{23,24}.C.