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