| 1 | // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s |
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| 2 | // UNSUPPORTED: ios |
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| 3 | |
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| 4 | #include <pthread.h> |
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| 5 | #include <stdio.h> |
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| 6 | #include <stdlib.h> |
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| 7 | #include <unistd.h> |
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| 8 | #include <sys/types.h> |
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| 9 | |
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| 10 | int fds[2]; |
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| 11 | int X; |
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| 12 | |
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| 13 | void *Thread1(void *x) { |
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| 14 | X = 42; |
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| 15 | write(fd: fds[1], buf: "a" , n: 1); |
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| 16 | return NULL; |
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| 17 | } |
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| 18 | |
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| 19 | void *Thread2(void *x) { |
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| 20 | char buf; |
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| 21 | while (read(fd: fds[0], buf: &buf, nbytes: 1) != 1) { |
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| 22 | } |
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| 23 | X = 43; |
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| 24 | return NULL; |
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| 25 | } |
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| 26 | |
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| 27 | int main() { |
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| 28 | pipe(pipedes: fds); |
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| 29 | int pid = vfork(); |
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| 30 | if (pid < 0) { |
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| 31 | fprintf(stderr, format: "FAIL to vfork\n" ); |
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| 32 | exit(status: 1); |
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| 33 | } |
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| 34 | if (pid == 0) { // child |
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| 35 | // Closing of fds must not affect parent process. |
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| 36 | // Strictly saying this is undefined behavior, because vfork child is not |
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| 37 | // allowed to call any functions other than exec/exit. But this is what |
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| 38 | // openjdk does. |
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| 39 | close(fd: fds[0]); |
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| 40 | close(fd: fds[1]); |
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| 41 | _exit(status: 0); |
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| 42 | } |
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| 43 | pthread_t t[2]; |
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| 44 | pthread_create(newthread: &t[0], NULL, start_routine: Thread1, NULL); |
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| 45 | pthread_create(newthread: &t[1], NULL, start_routine: Thread2, NULL); |
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| 46 | pthread_join(th: t[0], NULL); |
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| 47 | pthread_join(th: t[1], NULL); |
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| 48 | fprintf(stderr, format: "DONE\n" ); |
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| 49 | } |
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| 50 | |
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| 51 | // CHECK-NOT: WARNING: ThreadSanitizer: data race |
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| 52 | // CHECK-NOT: FAIL to vfork |
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| 53 | // CHECK: DONE |
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| 54 | |
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