forked from OSchip/llvm-project
41 lines
1010 B
C
41 lines
1010 B
C
// RUN: %clang_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s
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#include "test.h"
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// We want to establish the following sequence of accesses to X:
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// - main thread writes X
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// - thread2 reads X, this read happens-before the write in main thread
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// - thread1 reads X, this read is concurrent with the write in main thread
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// Write in main thread and read in thread1 should be detected as a race.
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// Previously tsan replaced write by main thread with read by thread1,
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// as the result the race was not detected.
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volatile long X, Y, Z;
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void *Thread1(void *x) {
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barrier_wait(&barrier);
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barrier_wait(&barrier);
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Y = X;
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return NULL;
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}
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void *Thread2(void *x) {
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Z = X;
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barrier_wait(&barrier);
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return NULL;
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}
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int main() {
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barrier_init(&barrier, 2);
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pthread_t t[2];
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pthread_create(&t[0], 0, Thread1, 0);
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X = 42;
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barrier_wait(&barrier);
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pthread_create(&t[1], 0, Thread2, 0);
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pthread_join(t[0], 0);
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pthread_join(t[1], 0);
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return 0;
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}
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// CHECK: WARNING: ThreadSanitizer: data race
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