1 /* RUN: %clang_msan -g -m64 %s -o %t 2 RUN: %clang_msan -g -m64 %s -DBUILD_SO -fPIC -o %t-so.so -shared 3 RUN: %run %t 2>&1 4 5 Regression test for a bug in msan/glibc integration, 6 see https://sourceware.org/bugzilla/show_bug.cgi?id=16291 7 and https://code.google.com/p/memory-sanitizer/issues/detail?id=44 8 */ 9 10 #ifndef BUILD_SO 11 #include <assert.h> 12 #include <dlfcn.h> 13 #include <stdio.h> 14 #include <stdlib.h> 15 #include <pthread.h> 16 17 typedef long *(* get_t)(); 18 get_t GetTls; 19 void *Thread1(void *unused) { 20 long uninitialized; 21 long *x = GetTls(); 22 if (*x) 23 fprintf(stderr, "bar\n"); 24 *x = uninitialized; 25 fprintf(stderr, "stack: %p dtls: %p\n", &x, x); 26 return 0; 27 } 28 29 void *Thread2(void *unused) { 30 long *x = GetTls(); 31 fprintf(stderr, "stack: %p dtls: %p\n", &x, x); 32 if (*x) 33 fprintf(stderr, "foo\n"); // False negative here. 34 return 0; 35 } 36 37 int main(int argc, char *argv[]) { 38 char path[4096]; 39 snprintf(path, sizeof(path), "%s-so.so", argv[0]); 40 int i; 41 42 void *handle = dlopen(path, RTLD_LAZY); 43 if (!handle) fprintf(stderr, "%s\n", dlerror()); 44 assert(handle != 0); 45 GetTls = (get_t)dlsym(handle, "GetTls"); 46 assert(dlerror() == 0); 47 48 pthread_t t; 49 pthread_create(&t, 0, Thread1, 0); 50 pthread_join(t, 0); 51 pthread_create(&t, 0, Thread2, 0); 52 pthread_join(t, 0); 53 return 0; 54 } 55 #else // BUILD_SO 56 __thread long huge_thread_local_array[1 << 17]; 57 long *GetTls() { 58 return &huge_thread_local_array[0]; 59 } 60 #endif 61