1// RUN: %clangxx_tsan -O0 %s -o %t
2// RUN: not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-NORMAL
3// RUN: %env_tsan_opts=ignore_interceptors_accesses=1 %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-IGNORE
4
5#include <errno.h>
6#include <sys/mman.h>
7
8#include "test.h"
9
10extern "C" {
11void AnnotateIgnoreReadsBegin(const char *f, int l);
12void AnnotateIgnoreReadsEnd(const char *f, int l);
13void AnnotateIgnoreWritesBegin(const char *f, int l);
14void AnnotateIgnoreWritesEnd(const char *f, int l);
15}
16
17void *global_p;
18
19int mmap_and_ignore_reads_and_writes() {
20  const size_t kSize = sysconf(_SC_PAGESIZE);
21  void *p = mmap(0, kSize, PROT_READ|PROT_WRITE,
22                 MAP_PRIVATE|MAP_ANON, -1, 0);
23  if (p == MAP_FAILED)
24    return printf("mmap failed with %d\n", errno);
25  munmap(p, kSize);
26
27  void *new_p = mmap(p, kSize, PROT_READ|PROT_WRITE,
28                     MAP_PRIVATE|MAP_ANON, -1, 0);
29  if (p == MAP_FAILED || p != new_p)
30    return printf("second mmap failed with %d\n", errno);
31
32  AnnotateIgnoreWritesBegin(__FILE__, __LINE__);
33  global_p = p;
34  AnnotateIgnoreWritesEnd(__FILE__, __LINE__);
35  barrier_wait(&barrier);
36  return 0;
37}
38
39void *Thread(void *a) {
40  barrier_wait(&barrier);
41
42  ((int*)global_p)[1] = 10;
43  printf("Read the zero value from mmapped memory %d\n", ((int*)global_p)[1]);
44  return 0;
45}
46
47int main() {
48  barrier_init(&barrier, 2);
49  pthread_t t;
50  pthread_create(&t, 0, Thread, 0);
51  if (mmap_and_ignore_reads_and_writes())
52    return 1;
53  pthread_join(t, 0);
54  printf("OK\n");
55  return 0;
56}
57
58// CHECK-NORMAL: WARNING: ThreadSanitizer: data race
59// CHECK-NORMAL: OK
60// CHECK-IGNORE_NOT: WARNING: ThreadSanitizer: data race
61// CHECK-IGNORE: OK
62