1  // RUN: %clangxx_tsan -O1 %s -DBUILD_SO -fPIC -shared -o %t-so.so
 2  // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
 3  
 4  // If we mention TSAN_OPTIONS, the test won't run from test_output.sh script.
 5  
 6  #ifdef BUILD_SO
 7  
 8  #include "test.h"
 9  
10  int exported_var = 0;
11  
12  #else  // BUILD_SO
13  
14  #include "test.h"
15  #include <dlfcn.h>
16  #include <link.h>
17  #include <string.h>
18  #include <string>
19  
20  static int callback(struct dl_phdr_info *info, size_t size, void *data) {
21    if (info->dlpi_name[0] == '\0')
22      info->dlpi_name = "/proc/self/exe";
23    return !strcmp(info->dlpi_name, "non existent module");
24  }
25  
26  void *thread(void *unused) {
27    for (int i = 0; i < 1000; i++) {
28      barrier_wait(&barrier);
29      dl_iterate_phdr(callback, 0);
30    }
31    return 0;
32  }
33  
34  int main(int argc, char *argv[]) {
35    barrier_init(&barrier, 2);
36    std::string path = std::string(argv[0]) + std::string("-so.so");
37    pthread_t th;
38    pthread_create(&th, 0, thread, 0);
39    for (int i = 0; i < 1000; i++) {
40      barrier_wait(&barrier);
41      void *lib = dlopen(path.c_str(), RTLD_NOW);
42      if (!lib) {
43        printf("error in dlopen: %s\n", dlerror());
44        return 1;
45      }
46      dlclose(lib);
47    }
48    pthread_join(th, 0);
49    printf("DONE\n");
50    return 0;
51  }
52  
53  #endif  // BUILD_SO
54  
55  // CHECK-NOT: WARNING: ThreadSanitizer: data race
56  // CHECK: DONE