C ISA2+pooncelock+pooncelock+pombonce (* * Result: Never * * This test shows that write-write ordering provided by locks * (in P0() and P1()) is visible to external process P2(). *) {} P0(int *x, int *y, spinlock_t *mylock) { spin_lock(mylock); WRITE_ONCE(*x, 1); WRITE_ONCE(*y, 1); spin_unlock(mylock); } P1(int *y, int *z, spinlock_t *mylock) { int r0; spin_lock(mylock); r0 = READ_ONCE(*y); WRITE_ONCE(*z, 1); spin_unlock(mylock); } P2(int *x, int *z) { int r1; int r2; r2 = READ_ONCE(*z); smp_mb(); r1 = READ_ONCE(*x); } exists (1:r0=1 /\ 2:r2=1 /\ 2:r1=0)