C SB+poonceonces (* * Result: Sometimes * * This litmus test demonstrates that at least some ordering is required * to order the store-buffering pattern, where each process writes to the * variable that the preceding process reads. *) {} P0(int *x, int *y) { int r0; WRITE_ONCE(*x, 1); r0 = READ_ONCE(*y); } P1(int *x, int *y) { int r0; WRITE_ONCE(*y, 1); r0 = READ_ONCE(*x); } exists (0:r0=0 /\ 1:r0=0)