--- /dev/null
+/* { dg-do run } */
+/* { dg-additional-options "-DSYNC_FALLBACK" { target { ! cas_int } } } */
+
+#ifdef SYNC_FALLBACK
+/* The SYNC_FALLBACK code is just so we don't have to restrict this test
+ to any subset of targets. For targets with no atomics support at
+ all, the cas_int effective-target is false and the fallback provides
+ a PASS. Where the bug trigs (at the time this test-case was added),
+ cas_int is also false but the fallback isn't used. */
+__attribute__((__noinline__, __noclone__))
+int
+# if __INT_MAX__ == 0x7fff
+ __sync_fetch_and_add_2
+# else
+ __sync_fetch_and_add_4
+# endif
+ (int *at, int val)
+{
+ int tmp = *at;
+ asm ("");
+ *at = tmp + val;
+ return tmp;
+}
+#endif
+
+__attribute__((__noinline__, __noclone__))
+void g (int *at, int val)
+{
+ asm ("");
+ __sync_fetch_and_add (at, val);
+}
+
+int main(void)
+{
+ int x = 41;
+ int a = 1;
+ g (&x, a);
+
+ if (x != 42)
+ __builtin_abort ();
+ __builtin_exit (0);
+}