// RUN: %clangxx_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s #include <pthread.h> #include <unistd.h> #include <stdio.h> const int kTestCount = 4; typedef long long T; T atomics[kTestCount * 2]; void Test(int test, T *p, bool main_thread) { volatile T sink; if (test == 0) { if (main_thread) __atomic_fetch_add(p, 1, __ATOMIC_RELAXED); else *p = 42; } else if (test == 1) { if (main_thread) __atomic_fetch_add(p, 1, __ATOMIC_RELAXED); else sink = *p; } else if (test == 2) { if (main_thread) sink = __atomic_load_n(p, __ATOMIC_SEQ_CST); else *p = 42; } else if (test == 3) { if (main_thread) __atomic_store_n(p, 1, __ATOMIC_SEQ_CST); else sink = *p; } } void *Thread(void *p) { for (int i = 0; i < kTestCount; i++) { Test(i, &atomics[i], false); } sleep(2); for (int i = 0; i < kTestCount; i++) { fprintf(stderr, "Test %d reverse\n", i); Test(i, &atomics[kTestCount + i], false); } return 0; } int main() { pthread_t t; pthread_create(&t, 0, Thread, 0); sleep(1); for (int i = 0; i < kTestCount; i++) { fprintf(stderr, "Test %d\n", i); Test(i, &atomics[i], true); } for (int i = 0; i < kTestCount; i++) { Test(i, &atomics[kTestCount + i], true); } pthread_join(t, 0); } // CHECK: Test 0 // CHECK: ThreadSanitizer: data race // CHECK-NOT: SUMMARY{{.*}}tsan_interface_atomic // CHECK: Test 1 // CHECK: ThreadSanitizer: data race // CHECK-NOT: SUMMARY{{.*}}tsan_interface_atomic // CHECK: Test 2 // CHECK: ThreadSanitizer: data race // CHECK-NOT: SUMMARY{{.*}}tsan_interface_atomic // CHECK: Test 3 // CHECK: ThreadSanitizer: data race // CHECK-NOT: SUMMARY{{.*}}tsan_interface_atomic // CHECK: Test 0 reverse // CHECK: ThreadSanitizer: data race // CHECK: Test 1 reverse // CHECK: ThreadSanitizer: data race // CHECK: Test 2 reverse // CHECK: ThreadSanitizer: data race // CHECK: Test 3 reverse // CHECK: ThreadSanitizer: data race