--- /dev/null
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+int main ()
+{
+struct a {
+ int x;
+ int y;
+ int z : 10;
+};
+
+struct b {
+ int x;
+ int y;
+};
+
+volatile struct b k;
+volatile struct a *p;
+
+p = (struct a*) &k;
+
+p->z = 'q';
+
+return 0;
+}
+/* { dg-output "mudflap violation 1.*" } */
+/* { dg-output "Nearby object 1.*" } */
+/* { dg-output "mudflap object.*.main. k.*" } */
+/* { dg-do run { xfail *-*-* } } */