| 1 | /* RUN: %clang_msan -g %s -o %t |
| 2 | RUN: %clang_msan -g %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://github.com/google/sanitizers/issues/547 |
| 8 | |
| 9 | XFAIL: target={{.*freebsd.*}} |
| 10 | UNSUPPORTED: target=powerpc{{.*}} |
| 11 | |
| 12 | // Reports use-of-uninitialized-value, not analyzed |
| 13 | XFAIL: target={{.*netbsd.*}} |
| 14 | |
| 15 | */ |
| 16 | |
| 17 | #ifndef BUILD_SO |
| 18 | #include <assert.h> |
| 19 | #include <dlfcn.h> |
| 20 | #include <stdio.h> |
| 21 | #include <stdlib.h> |
| 22 | #include <pthread.h> |
| 23 | |
| 24 | typedef long *(* get_t)(); |
| 25 | get_t GetTls; |
| 26 | void *Thread1(void *unused) { |
| 27 | long uninitialized; |
| 28 | long *x = GetTls(); |
| 29 | if (*x) |
| 30 | fprintf(stderr, format: "bar\n" ); |
| 31 | *x = uninitialized; |
| 32 | fprintf(stderr, format: "stack: %p dtls: %p\n" , &x, x); |
| 33 | return 0; |
| 34 | } |
| 35 | |
| 36 | void *Thread2(void *unused) { |
| 37 | long *x = GetTls(); |
| 38 | fprintf(stderr, format: "stack: %p dtls: %p\n" , &x, x); |
| 39 | if (*x) |
| 40 | fprintf(stderr, format: "foo\n" ); // False negative here. |
| 41 | return 0; |
| 42 | } |
| 43 | |
| 44 | int main(int argc, char *argv[]) { |
| 45 | char path[4096]; |
| 46 | snprintf(s: path, maxlen: sizeof(path), format: "%s-so.so" , argv[0]); |
| 47 | int i; |
| 48 | |
| 49 | void *handle = dlopen(file: path, RTLD_LAZY); |
| 50 | if (!handle) fprintf(stderr, format: "%s\n" , dlerror()); |
| 51 | assert(handle != 0); |
| 52 | GetTls = (get_t)dlsym(handle: handle, name: "GetTls" ); |
| 53 | assert(dlerror() == 0); |
| 54 | |
| 55 | pthread_t t; |
| 56 | pthread_create(newthread: &t, attr: 0, start_routine: Thread1, arg: 0); |
| 57 | pthread_join(th: t, thread_return: 0); |
| 58 | pthread_create(newthread: &t, attr: 0, start_routine: Thread2, arg: 0); |
| 59 | pthread_join(th: t, thread_return: 0); |
| 60 | return 0; |
| 61 | } |
| 62 | #else // BUILD_SO |
| 63 | __thread long huge_thread_local_array[1 << 17]; |
| 64 | long *GetTls() { |
| 65 | return &huge_thread_local_array[0]; |
| 66 | } |
| 67 | #endif |
| 68 | |