41 lines · cpp
1// RUN: %clang_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s2// CHECK-NOT: ThreadSanitizer: data race3// CHECK: DONE4 5// pthread barriers are not available on OS X6// UNSUPPORTED: darwin7 8#include <stdio.h>9#include <stdlib.h>10#include <pthread.h>11#include <unistd.h>12 13const int kSize = 4;14volatile int kIter = 10; // prevent unwinding15int data[2][kSize];16pthread_barrier_t barrier;17 18void *thr(void *p) {19 int idx = (int)(long)p;20 for (int i = 0; i < kIter; i++) {21 int *prev = data[i % 2];22 int *curr = data[(i + 1) % 2];23 int left = idx - 1 >= 0 ? prev[idx - 1] : 0;24 int right = idx + 1 < kSize ? prev[idx + 1] : 0;25 curr[idx] = (left + right) / 2;26 pthread_barrier_wait(&barrier);27 }28 return 0;29}30 31int main() {32 pthread_barrier_init(&barrier, 0, kSize);33 pthread_t th[kSize];34 for (int i = 0; i < kSize; i++)35 pthread_create(&th[i], 0, thr, (void*)(long)i);36 for (int i = 0; i < kSize; i++)37 pthread_join(th[i], 0);38 pthread_barrier_destroy(&barrier);39 fprintf(stderr, "DONE\n");40}41