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| // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
int fds[2];
int X;
void *Thread1(void *x) {
X = 42;
write(fds[1], "a", 1);
return NULL;
}
void *Thread2(void *x) {
char buf;
while (read(fds[0], &buf, 1) != 1) {
}
X = 43;
return NULL;
}
int main() {
pipe(fds);
int pid = vfork();
if (pid < 0) {
fprintf(stderr, "FAIL to vfork\n");
exit(1);
}
if (pid == 0) { // child
// Closing of fds must not affect parent process.
// Strictly saying this is undefined behavior, because vfork child is not
// allowed to call any functions other than exec/exit. But this is what
// openjdk does.
close(fds[0]);
close(fds[1]);
_exit(0);
}
pthread_t t[2];
pthread_create(&t[0], NULL, Thread1, NULL);
pthread_create(&t[1], NULL, Thread2, NULL);
pthread_join(t[0], NULL);
pthread_join(t[1], NULL);
fprintf(stderr, "DONE\n");
}
// CHECK-NOT: WARNING: ThreadSanitizer: data race
// CHECK-NOT: FAIL to vfork
// CHECK: DONE
|