llvm-project/compiler-rt/test/msan/dtls_test.c

61 lines
1.4 KiB
C

/* RUN: %clang_msan -m64 %s -o %t
RUN: %clang_msan -m64 %s -DBUILD_SO -fPIC -o %t-so.so -shared
RUN: not %t 2>&1 | FileCheck %s
CHECK: MemorySanitizer: use-of-uninitialized-value
This is an actual bug in msan/glibc integration,
see https://sourceware.org/bugzilla/show_bug.cgi?id=16291
*/
#ifndef BUILD_SO
#include <assert.h>
#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
typedef long *(* get_t)();
get_t GetTls;
void *Thread1(void *unused) {
long uninitialized;
long *x = GetTls();
if (*x)
fprintf(stderr, "bar\n");
*x = uninitialized;
fprintf(stderr, "stack: %p dtls: %p\n", &x, x);
return 0;
}
void *Thread2(void *unused) {
long *x = GetTls();
fprintf(stderr, "stack: %p dtls: %p\n", &x, x);
if (*x)
fprintf(stderr, "foo\n"); // False negative here.
return 0;
}
int main(int argc, char *argv[]) {
char path[4096];
snprintf(path, sizeof(path), "%s-so.so", argv[0]);
int i;
void *handle = dlopen(path, RTLD_LAZY);
if (!handle) fprintf(stderr, "%s\n", dlerror());
assert(handle != 0);
GetTls = (get_t)dlsym(handle, "GetTls");
assert(dlerror() == 0);
pthread_t t;
pthread_create(&t, 0, Thread1, 0);
pthread_join(t, 0);
pthread_create(&t, 0, Thread2, 0);
pthread_join(t, 0);
return 0;
}
#else // BUILD_SO
__thread long huge_thread_local_array[1 << 17];
long *GetTls() {
return &huge_thread_local_array[0];
}
#endif