1C R+poonceonces
 2
 3(*
 4 * Result: Sometimes
 5 *
 6 * This is the unordered (thus lacking smp_mb()) version of one of the
 7 * classic counterintuitive litmus tests that illustrates the effects of
 8 * store propagation delays.
 9 *)
10
11{}
12
13P0(int *x, int *y)
14{
15	WRITE_ONCE(*x, 1);
16	WRITE_ONCE(*y, 1);
17}
18
19P1(int *x, int *y)
20{
21	int r0;
22
23	WRITE_ONCE(*y, 2);
24	r0 = READ_ONCE(*x);
25}
26
27exists (y=2 /\ 1:r0=0)