I think it is useful to cover also this, rather than just arrays at the
flexible array member positions.
2023-03-01 Jakub Jelinek <jakub@redhat.com>
PR sanitizer/108894
* c-c++-common/ubsan/bounds-16.c: New test.
--- /dev/null
+/* PR sanitizer/108894 */
+/* { dg-do run } */
+/* { dg-options "-fsanitize=bounds -fsanitize-recover=bounds" } */
+/* { dg-output "index 1 out of bounds for type 'int \\\[\[*0-9x]*\\\]'\[^\n\r]*(\n|\r\n|\r)" } */
+/* { dg-output "\[^\n\r]*index 0 out of bounds for type 'int \\\[\[*0-9x]*\\\]'" } */
+
+struct S { int a; int b[0]; int c; } s;
+
+int
+main ()
+{
+ int *volatile p = &s.b[0];
+ p = &s.b[1];
+ int volatile q = s.b[0];
+}