free_race.c revision 86277eb844c4983c81de62d7c050e92fe7155788 
1// RUN: %clang_tsan -O1 %s -o %t
2// RUN: %deflake %run %t | FileCheck %s --check-prefix=CHECK-NOZUPP
3// RUN: TSAN_OPTIONS="suppressions='%s.supp' print_suppressions=1" %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-SUPP
4
5#include "test.h"
6
7int *mem;
8pthread_mutex_t mtx;
9
10void *Thread1(void *x) {
11  pthread_mutex_lock(&mtx);
12  free(mem);
13  pthread_mutex_unlock(&mtx);
14  barrier_wait(&barrier);
15  return NULL;
16}
17
18void *Thread2(void *x) {
19  barrier_wait(&barrier);
20  pthread_mutex_lock(&mtx);
21  mem[0] = 42;
22  pthread_mutex_unlock(&mtx);
23  return NULL;
24}
25
26int main() {
27  barrier_init(&barrier, 2);
28  mem = (int*)malloc(100);
29  pthread_mutex_init(&mtx, 0);
30  pthread_t t;
31  pthread_create(&t, NULL, Thread1, NULL);
32  Thread2(0);
33  pthread_join(t, NULL);
34  pthread_mutex_destroy(&mtx);
35  return 0;
36}
37
38// CHECK-NOZUPP: WARNING: ThreadSanitizer: heap-use-after-free
39// CHECK-NOZUPP:   Write of size 4 at {{.*}} by main thread{{.*}}:
40// CHECK-NOZUPP:     #0 Thread2
41// CHECK-NOZUPP:     #1 main
42// CHECK-NOZUPP:   Previous write of size 8 at {{.*}} by thread T1{{.*}}:
43// CHECK-NOZUPP:     #0 free
44// CHECK-NOZUPP:     #{{(1|2)}} Thread1
45// CHECK-NOZUPP: SUMMARY: ThreadSanitizer: heap-use-after-free{{.*}}Thread2
46// CHECK-SUPP:   ThreadSanitizer: Matched 1 suppressions
47// CHECK-SUPP:    1 race:^Thread2$
48