Hi Mike,
after some hours of sleep I realized that your step function can do something
very interesting,
(which you already requested previously):
That is: create a race condition that is _always_ at 100% missed by tsan:
cat lib.c
/* { dg-do compile } */
/* { dg-options "-O2 -fno-sanitize=all" } */
static volatile int serial = 0;
void step (int i)
{
while (__atomic_load_n (&serial, __ATOMIC_ACQUIRE) != i - 1);
__atomic_store_n (&serial, i, __ATOMIC_RELEASE);
}
cat tiny_race.c
/* { dg-shouldfail "tsan" } */
#include <pthread.h>
void step(int);
int Global;
void *Thread1(void *x) {
step (1);
Global = 42;
step (3);
return x;
}
int main() {
pthread_t t;
pthread_create(&t, 0, Thread1, 0);
step (2);
Global = 43;
step (4);
pthread_join(t, 0);
return Global;
}
/* { dg-output "WARNING: ThreadSanitizer: data race.*(\n|\r\n|\r)" } */
Bernd.
