C C-LB+o-o+o-o.litmus

{
}

P0(int *a, int *b)
{
	int r1;

	r1 = READ_ONCE(*a);
	WRITE_ONCE(*b, 1);
}

P1(int *a, int *b)
{
	int r1;

	r2 = READ_ONCE(*b);
	WRITE_ONCE(*a, 1);
}

exists
(0:r1=1 /\ 1:r2=1)