1 // RUN: %clang_tsan %s -o %t
2 // RUN: %clang_tsan %s -DBUILD_SO -fPIC -o %t-so.so -shared
3 // RUN: %run %t 2>&1 | FileCheck %s
4
5 // Test that tsan cleans up dynamic TLS memory between reuse.
6
7 #include "test.h"
8
9 #ifndef BUILD_SO
10 #include <assert.h>
11 #include <dlfcn.h>
12
13 typedef volatile long *(* get_t)();
14 get_t GetTls;
15
Thread1(void * arg)16 void *Thread1(void *arg) {
17 pthread_detach(pthread_self());
18 volatile long *x = GetTls();
19 *x = 42;
20 fprintf(stderr, "stack: %p dtls: %p\n", &x, x);
21 barrier_wait(&barrier);
22 return 0;
23 }
24
Thread2(void * arg)25 void *Thread2(void *arg) {
26 volatile long *x = GetTls();
27 *x = 42;
28 fprintf(stderr, "stack: %p dtls: %p\n", &x, x);
29 return 0;
30 }
31
main(int argc,char * argv[])32 int main(int argc, char *argv[]) {
33 char path[4096];
34 snprintf(path, sizeof(path), "%s-so.so", argv[0]);
35
36 void *handle = dlopen(path, RTLD_LAZY);
37 if (!handle) fprintf(stderr, "%s\n", dlerror());
38 assert(handle != 0);
39 GetTls = (get_t)dlsym(handle, "GetTls");
40 assert(dlerror() == 0);
41
42 barrier_init(&barrier, 2);
43 pthread_t t[2];
44 pthread_create(&t[0], 0, Thread1, 0);
45 barrier_wait(&barrier);
46 // Wait for actual thread termination without using pthread_join,
47 // which would synchronize threads.
48 sleep(1);
49 pthread_create(&t[1], 0, Thread2, 0);
50 pthread_join(t[1], 0);
51 fprintf(stderr, "DONE\n");
52 return 0;
53 }
54 #else // BUILD_SO
55 __thread long huge_thread_local_array[1 << 17];
GetTls()56 long *GetTls() {
57 return &huge_thread_local_array[0];
58 }
59 #endif
60
61 // CHECK-NOT: ThreadSanitizer: data race
62 // CHECK: DONE
63