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C MP+poonceonces
(*
* Result: Sometimes
*
* Can the counter-intuitive message-passing outcome be prevented with
* no ordering at all?
*)
{
int buf;
int flag;
}
P0(int *buf, int *flag) // Producer
{
WRITE_ONCE(*buf, 1);
WRITE_ONCE(*flag, 1);
}
P1(int *buf, int *flag) // Consumer
{
int r0;
int r1;
r0 = READ_ONCE(*flag);
r1 = READ_ONCE(*buf);
}
exists (1:r0=1 /\ 1:r1=0) (* Bad outcome. *)
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