1// RUN: %clang_cl_asan %s -Fe%t.exe /MD
2// RUN: %run %t.exe | FileCheck %s
3
4// CHECK: my_thread_callback
5// CHECK: ran_before_main: 1
6
7#include <windows.h>
8#include <stdio.h>
9#include <string.h>
10
11#pragma comment (lib, "dbghelp")
12
13static bool ran_before_main = false;
14
15extern "C" void __asan_init(void);
16
17static void NTAPI /*__attribute__((no_sanitize_address))*/
18my_thread_callback(PVOID module, DWORD reason, PVOID reserved) {
19 ran_before_main = true;
20 static const char str[] = "my_thread_callback\n";
21
22 // Fail the test if we aren't called for the expected reason or we can't write
23 // stdout.
24 if (reason != DLL_PROCESS_ATTACH)
25 return;
26 HANDLE out = GetStdHandle(STD_OUTPUT_HANDLE);
27 if (!out || out == INVALID_HANDLE_VALUE)
28 return;
29
30 DWORD written = 0;
31 WriteFile(out, &str[0], sizeof(str), &written, NULL);
32}
33
34extern "C" {
35#pragma const_seg(".CRT$XLC")
36extern const PIMAGE_TLS_CALLBACK p_thread_callback;
37const PIMAGE_TLS_CALLBACK p_thread_callback = my_thread_callback;
38#pragma const_seg()
39}
40
41#ifdef _WIN64
42#pragma comment(linker, "/INCLUDE:_tls_used")
43#pragma comment(linker, "/INCLUDE:p_thread_callback")
44#else
45#pragma comment(linker, "/INCLUDE:__tls_used")
46#pragma comment(linker, "/INCLUDE:_p_thread_callback")
47#endif
48
49int main() {
50 printf(format: "ran_before_main: %d\n", ran_before_main);
51}
52

source code of compiler-rt/test/asan/TestCases/Windows/msvc/tls_init.cpp