[compiler-rt] [compiler-rt] Support Windows GNU sanitizer runtimes (PR #209902)
via llvm-commits
llvm-commits at lists.llvm.org
Thu Jul 16 11:49:32 PDT 2026
https://github.com/oltolm updated https://github.com/llvm/llvm-project/pull/209902
>From 4671b848aa10f07aa60618766a687a2fa4af72c5 Mon Sep 17 00:00:00 2001
From: Oleg Tolmatcev <oleg.tolmatcev at gmail.com>
Date: Wed, 15 Jul 2026 18:07:03 +0200
Subject: [PATCH 1/3] [compiler-rt] Support Windows GNU sanitizer runtimes
Handle Windows GNU-specific section and weak-symbol behavior in the sanitizer runtime. Keep Clang on the existing Windows path because it also defines __GNUC__ on Windows.
Co-authored-by: Hannes Domani <ssbssa at yahoo.de>
---
compiler-rt/lib/asan/asan_globals_win.cpp | 31 +++++----
compiler-rt/lib/asan/asan_malloc_win.cpp | 14 +++--
compiler-rt/lib/asan/asan_win.cpp | 63 +++++++++++++++----
.../asan/asan_win_common_runtime_thunk.cpp | 11 ++--
.../lib/asan/asan_win_common_runtime_thunk.h | 20 +++---
.../asan/asan_win_dynamic_runtime_thunk.cpp | 8 +--
compiler-rt/lib/builtins/emutls.c | 1 +
compiler-rt/lib/builtins/gcc_personality_v0.c | 2 +-
.../lib/interception/interception_win.cpp | 27 ++++++++
.../sanitizer_internal_defs.h | 8 +--
.../lib/sanitizer_common/sanitizer_win.cpp | 8 ++-
.../lib/sanitizer_common/sanitizer_win_defs.h | 26 ++++++--
.../sanitizer_win_thunk_interception.cpp | 24 ++++---
.../sanitizer_win_thunk_interception.h | 48 ++++++++------
compiler-rt/lib/ubsan/ubsan_handlers.cpp | 7 ++-
15 files changed, 203 insertions(+), 95 deletions(-)
diff --git a/compiler-rt/lib/asan/asan_globals_win.cpp b/compiler-rt/lib/asan/asan_globals_win.cpp
index 2b59595dcd3bf..5c038ebb3f228 100644
--- a/compiler-rt/lib/asan/asan_globals_win.cpp
+++ b/compiler-rt/lib/asan/asan_globals_win.cpp
@@ -12,16 +12,23 @@
#include "asan_interface_internal.h"
#if SANITIZER_WINDOWS
+# include "sanitizer_common/sanitizer_win_defs.h"
+
+# if defined(__GNUC__) && !defined(__clang__)
+extern "C" void __debugbreak();
+# endif
namespace __asan {
-#pragma section(".ASAN$GA", read, write)
-#pragma section(".ASAN$GZ", read, write)
+# if !defined(__GNUC__) || defined(__clang__)
+# pragma section(".ASAN$GA", read, write)
+# pragma section(".ASAN$GZ", read, write)
+# endif
extern "C" alignas(sizeof(__asan_global))
- __declspec(allocate(".ASAN$GA")) __asan_global __asan_globals_start = {};
+ IN_SECTION(".ASAN$GA") __asan_global __asan_globals_start = {};
extern "C" alignas(sizeof(__asan_global))
- __declspec(allocate(".ASAN$GZ")) __asan_global __asan_globals_end = {};
-#pragma comment(linker, "/merge:.ASAN=.data")
+ IN_SECTION(".ASAN$GZ") __asan_global __asan_globals_end = {};
+# pragma comment(linker, "/merge:.ASAN=.data")
static void call_on_globals(void (*hook)(__asan_global *, uptr)) {
__asan_global *start = &__asan_globals_start + 1;
@@ -51,12 +58,14 @@ static void unregister_dso_globals() {
}
// Register globals
-#pragma section(".CRT$XCU", long, read)
-#pragma section(".CRT$XTX", long, read)
-extern "C" __declspec(allocate(".CRT$XCU"))
-void (*const __asan_dso_reg_hook)() = ®ister_dso_globals;
-extern "C" __declspec(allocate(".CRT$XTX"))
-void (*const __asan_dso_unreg_hook)() = &unregister_dso_globals;
+# if !defined(__GNUC__) || defined(__clang__)
+# pragma section(".CRT$XCU", long, read)
+# pragma section(".CRT$XTX", long, read)
+# endif
+extern "C" IN_SECTION(".CRT$XCU") void (*const __asan_dso_reg_hook)() =
+ ®ister_dso_globals;
+extern "C" IN_SECTION(".CRT$XTX") void (*const __asan_dso_unreg_hook)() =
+ &unregister_dso_globals;
} // namespace __asan
diff --git a/compiler-rt/lib/asan/asan_malloc_win.cpp b/compiler-rt/lib/asan/asan_malloc_win.cpp
index e728591cc145e..abb1b496d1b40 100644
--- a/compiler-rt/lib/asan/asan_malloc_win.cpp
+++ b/compiler-rt/lib/asan/asan_malloc_win.cpp
@@ -14,12 +14,14 @@
#include "sanitizer_common/sanitizer_allocator_interface.h"
#include "sanitizer_common/sanitizer_platform.h"
#if SANITIZER_WINDOWS
-#include "asan_allocator.h"
-#include "asan_interceptors.h"
-#include "asan_internal.h"
-#include "asan_stack.h"
-#include "interception/interception.h"
-#include <stddef.h>
+# include <stddef.h>
+
+# include "asan_allocator.h"
+# include "asan_interceptors.h"
+# include "asan_internal.h"
+# include "asan_stack.h"
+# include "interception/interception.h"
+# include "sanitizer_common/sanitizer_win_defs.h"
// Intentionally not including windows.h here, to avoid the risk of
// pulling in conflicting declarations of these functions. (With mingw-w64,
diff --git a/compiler-rt/lib/asan/asan_win.cpp b/compiler-rt/lib/asan/asan_win.cpp
index 845408ac38abc..2e6781988d5eb 100644
--- a/compiler-rt/lib/asan/asan_win.cpp
+++ b/compiler-rt/lib/asan/asan_win.cpp
@@ -15,6 +15,9 @@
#include "sanitizer_common/sanitizer_platform.h"
#if SANITIZER_WINDOWS
# define WIN32_LEAN_AND_MEAN
+# if defined(__GNUC__) && !defined(__clang__)
+# include <malloc.h>
+# endif
# include <stdlib.h>
# include <windows.h>
@@ -228,7 +231,17 @@ void FlushUnneededASanShadowMemory(uptr p, uptr size) {
// ---------------------- TSD ---------------- {{{
static bool tsd_key_inited = false;
+# if !defined(__GNUC__) || defined(__clang__)
static __declspec(thread) void *fake_tsd = 0;
+# else
+struct TlsVoidPtr {
+ operator void*() { return TlsGetValue(tls_index); }
+ void operator=(void* v) { TlsSetValue(tls_index, v); }
+
+ DWORD tls_index;
+};
+static TlsVoidPtr fake_tsd;
+# endif
// https://docs.microsoft.com/en-us/windows/desktop/api/winternl/ns-winternl-_teb
// "[This structure may be altered in future versions of Windows. Applications
@@ -261,7 +274,7 @@ void AsanTSDInit(void (*destructor)(void *tsd)) {
void *AsanTSDGet() {
CHECK(tsd_key_inited);
- return IsTlsInitialized() ? fake_tsd : nullptr;
+ return IsTlsInitialized() ? (void*)fake_tsd : nullptr;
}
void AsanTSDSet(void *tsd) {
@@ -332,7 +345,12 @@ ShadowExceptionHandler(PEXCEPTION_POINTERS exception_pointers) {
#endif
void InitializePlatformExceptionHandlers() {
-#if SANITIZER_WINDOWS64
+# if defined(__GNUC__) && !defined(__clang__)
+ fake_tsd.tls_index = TlsAlloc();
+ CHECK(fake_tsd.tls_index != TLS_OUT_OF_INDEXES);
+# endif
+
+# if SANITIZER_WINDOWS64
// On Win64, we map memory on demand with access violation handler.
// Install our exception handler.
CHECK(AddVectoredExceptionHandler(TRUE, &ShadowExceptionHandler));
@@ -340,7 +358,19 @@ void InitializePlatformExceptionHandlers() {
}
bool IsSystemHeapAddress(uptr addr) {
- return ::HeapValidate(GetProcessHeap(), 0, (void *)addr) != FALSE;
+ HANDLE process_heap = GetProcessHeap();
+ if (::HeapValidate(process_heap, 0, (void*)addr))
+ return true;
+
+# if defined(__GNUC__) && !defined(__clang__)
+ HANDLE crt_heap = (HANDLE)_get_heap_handle();
+ if (crt_heap == process_heap)
+ return false;
+
+ return ::HeapValidate(crt_heap, 0, (void*)addr) != FALSE;
+# else
+ return false;
+# endif
}
// We want to install our own exception handler (EH) to print helpful reports
@@ -384,9 +414,10 @@ bool HandleDlopenInit() {
// beginning of C++ initialization. We set our priority to XCAB to run
// immediately after the CRT runs. This way, our exception filter is called
// first and we can delegate to their filter if appropriate.
-#pragma section(".CRT$XCAB", long, read)
-__declspec(allocate(".CRT$XCAB")) int (*__intercept_seh)() =
- __asan_set_seh_filter;
+# if !defined(__GNUC__) || defined(__clang__)
+# pragma section(".CRT$XCAB", long, read)
+# endif
+IN_SECTION(".CRT$XCAB") int (*__intercept_seh)() = __asan_set_seh_filter;
// Piggyback on the TLS initialization callback directory to initialize asan as
// early as possible. Initializers in .CRT$XL* are called directly by ntdll,
@@ -397,10 +428,12 @@ static void NTAPI asan_thread_init(void *module, DWORD reason, void *reserved) {
__asan_init();
}
-#pragma section(".CRT$XLAB", long, read)
-__declspec(allocate(".CRT$XLAB")) void(NTAPI *__asan_tls_init)(
- void *, unsigned long, void *) = asan_thread_init;
-#endif
+# if !defined(__GNUC__) || defined(__clang__)
+# pragma section(".CRT$XLAB", long, read)
+# endif
+IN_SECTION(".CRT$XLAB")
+void(NTAPI* __asan_tls_init)(void*, unsigned long, void*) = asan_thread_init;
+# endif
static void NTAPI asan_thread_exit(void *module, DWORD reason, void *reserved) {
if (reason == DLL_THREAD_DETACH) {
@@ -411,9 +444,13 @@ static void NTAPI asan_thread_exit(void *module, DWORD reason, void *reserved) {
}
}
-#pragma section(".CRT$XLY", long, read)
-__declspec(allocate(".CRT$XLY")) void(NTAPI *__asan_tls_exit)(
- void *, unsigned long, void *) = asan_thread_exit;
+# if !defined(__GNUC__) || defined(__clang__)
+# pragma section(".CRT$XLY", long, read)
+# endif
+IN_SECTION(".CRT$XLY")
+void(NTAPI* __asan_tls_exit)(void*, unsigned long, void*) = asan_thread_exit;
+
+extern "C" void (*const __asan_dso_reg_hook)();
WIN_FORCE_LINK(__asan_dso_reg_hook)
diff --git a/compiler-rt/lib/asan/asan_win_common_runtime_thunk.cpp b/compiler-rt/lib/asan/asan_win_common_runtime_thunk.cpp
index 056e49336d326..1c6bac48141b2 100644
--- a/compiler-rt/lib/asan/asan_win_common_runtime_thunk.cpp
+++ b/compiler-rt/lib/asan/asan_win_common_runtime_thunk.cpp
@@ -83,12 +83,11 @@ static void WINAPI asan_thread_init(void *mod, unsigned long reason,
// Our cloned variables must be initialized before C/C++ constructors. If TLS
// is used, our .CRT$XLAB initializer will run first. If not, our .CRT$XIB
// initializer is needed as a backup.
-extern "C" __declspec(allocate(".CRT$XIB")) int (*__asan_thunk_init)() =
- asan_thunk_init;
+extern "C" IN_SECTION(".CRT$XIB") int (*__asan_thunk_init)() = asan_thunk_init;
WIN_FORCE_LINK(__asan_thunk_init)
-extern "C" __declspec(allocate(".CRT$XLAB")) void(WINAPI *__asan_tls_init)(
- void *, unsigned long, void *) = asan_thread_init;
+extern "C" IN_SECTION(".CRT$XLAB") void(WINAPI* __asan_tls_init)(
+ void*, unsigned long, void*) = asan_thread_init;
WIN_FORCE_LINK(__asan_tls_init)
////////////////////////////////////////////////////////////////////////////////
@@ -101,12 +100,14 @@ static int SetSEHFilter() { return __asan_set_seh_filter(); }
// Unfortunately, putting a pointer to __asan_set_seh_filter into
// __asan_intercept_seh gets optimized out, so we have to use an extra function.
-extern "C" __declspec(allocate(".CRT$XCAB")) int (*__asan_seh_interceptor)() =
+extern "C" IN_SECTION(".CRT$XCAB") int (*__asan_seh_interceptor)() =
SetSEHFilter;
WIN_FORCE_LINK(__asan_seh_interceptor)
}
+# ifdef SANITIZER_STATIC_RUNTIME_THUNK
WIN_FORCE_LINK(__asan_dso_reg_hook)
+# endif
#endif // defined(SANITIZER_DYNAMIC_RUNTIME_THUNK) ||
// defined(SANITIZER_STATIC_RUNTIME_THUNK)
diff --git a/compiler-rt/lib/asan/asan_win_common_runtime_thunk.h b/compiler-rt/lib/asan/asan_win_common_runtime_thunk.h
index 159cc152474e7..fcb695e0fa92a 100644
--- a/compiler-rt/lib/asan/asan_win_common_runtime_thunk.h
+++ b/compiler-rt/lib/asan/asan_win_common_runtime_thunk.h
@@ -18,17 +18,19 @@
defined(SANITIZER_DYNAMIC_RUNTIME_THUNK)
# include "sanitizer_common/sanitizer_win_defs.h"
-# pragma section(".CRT$XIB", long, \
- read) // C initializer (during C init before dyninit)
-# pragma section(".CRT$XID", long, \
- read) // First C initializer after CRT initializers
-# pragma section(".CRT$XCAB", long, \
- read) // First C++ initializer after startup initializers
+# if !defined(__GNUC__) || defined(__clang__)
+# pragma section(".CRT$XIB", long, \
+ read) // C initializer (during C init before dyninit)
+# pragma section(".CRT$XID", long, \
+ read) // First C initializer after CRT initializers
+# pragma section(".CRT$XCAB", long, \
+ read) // First C++ initializer after startup initializers
-# pragma section(".CRT$XTW", long, read) // First ASAN globals terminator
-# pragma section(".CRT$XTY", long, read) // Last ASAN globals terminator
+# pragma section(".CRT$XTW", long, read) // First ASAN globals terminator
+# pragma section(".CRT$XTY", long, read) // Last ASAN globals terminator
-# pragma section(".CRT$XLAB", long, read) // First TLS initializer
+# pragma section(".CRT$XLAB", long, read) // First TLS initializer
+# endif
# ifdef SANITIZER_STATIC_RUNTIME_THUNK
extern "C" void __asan_initialize_static_thunk();
diff --git a/compiler-rt/lib/asan/asan_win_dynamic_runtime_thunk.cpp b/compiler-rt/lib/asan/asan_win_dynamic_runtime_thunk.cpp
index 421fe651b7d91..2a864aa4ee8c1 100644
--- a/compiler-rt/lib/asan/asan_win_dynamic_runtime_thunk.cpp
+++ b/compiler-rt/lib/asan/asan_win_dynamic_runtime_thunk.cpp
@@ -33,8 +33,8 @@ extern "C" int __cdecl atexit(void(__cdecl *f)(void));
extern "C" void __cdecl _initterm(void *a, void *b);
namespace {
-__declspec(allocate(".CRT$XTW")) void *before_global_dtors = 0;
-__declspec(allocate(".CRT$XTY")) void *after_global_dtors = 0;
+IN_SECTION(".CRT$XTW") void* before_global_dtors = 0;
+IN_SECTION(".CRT$XTY") void* after_global_dtors = 0;
void UnregisterGlobals() {
_initterm(&before_global_dtors, &after_global_dtors);
@@ -47,8 +47,8 @@ int ScheduleUnregisterGlobals() { return atexit(UnregisterGlobals); }
// atexit() is initialized (.CRT$XIC). As this is executed before C++
// initializers (think ctors for globals), UnregisterGlobals gets executed after
// dtors for C++ globals.
-extern "C" __declspec(allocate(".CRT$XID")) int (
- *__asan_schedule_unregister_globals)() = ScheduleUnregisterGlobals;
+extern "C" IN_SECTION(".CRT$XID") int (*__asan_schedule_unregister_globals)() =
+ ScheduleUnregisterGlobals;
WIN_FORCE_LINK(__asan_schedule_unregister_globals)
#endif // SANITIZER_DYNAMIC_RUNTIME_THUNK
diff --git a/compiler-rt/lib/builtins/emutls.c b/compiler-rt/lib/builtins/emutls.c
index a8a5d7c0749a8..9d127e991a9b4 100644
--- a/compiler-rt/lib/builtins/emutls.c
+++ b/compiler-rt/lib/builtins/emutls.c
@@ -138,6 +138,7 @@ static __inline void emutls_unlock(void) { pthread_mutex_unlock(&emutls_mutex);
#include <assert.h>
#include <malloc.h>
#include <stdio.h>
+#define WIN32_LEAN_AND_MEAN 1
#include <windows.h>
static LPCRITICAL_SECTION emutls_mutex;
diff --git a/compiler-rt/lib/builtins/gcc_personality_v0.c b/compiler-rt/lib/builtins/gcc_personality_v0.c
index 6d92a7b248f3c..02d4e65d78d1c 100644
--- a/compiler-rt/lib/builtins/gcc_personality_v0.c
+++ b/compiler-rt/lib/builtins/gcc_personality_v0.c
@@ -22,8 +22,8 @@
#endif
#if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
+#define WIN32_LEAN_AND_MEAN 1
#include <windows.h>
-#include <winnt.h>
EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD, void *, PCONTEXT,
PDISPATCHER_CONTEXT,
diff --git a/compiler-rt/lib/interception/interception_win.cpp b/compiler-rt/lib/interception/interception_win.cpp
index 19bccb3566d72..6fd1f97308cdd 100644
--- a/compiler-rt/lib/interception/interception_win.cpp
+++ b/compiler-rt/lib/interception/interception_win.cpp
@@ -1110,6 +1110,33 @@ bool OverrideFunctionWithDetour(
bool OverrideFunctionWithRedirectJump(
uptr old_func, uptr new_func, uptr *orig_old_func) {
+# if SANITIZER_WINDOWS64 && defined(__GNUC__) && !defined(__clang__)
+ u8* old_u8 = (u8*)old_func;
+
+ // relative indirect jump
+ if (old_u8[0] == 0xff && old_u8[1] == 0x25) {
+ sptr relative_offset = *(s32*)(old_func + 2);
+ uptr* absolute_target_ptr = (uptr*)(old_func + 6 + relative_offset);
+ if (orig_old_func)
+ *orig_old_func = *absolute_target_ptr;
+
+ // Change memory protection to writable.
+ DWORD protection = 0;
+ if (!ChangeMemoryProtection((uptr)absolute_target_ptr, sizeof(uptr),
+ &protection))
+ return false;
+
+ *absolute_target_ptr = new_func;
+
+ // Restore previous memory protection.
+ if (!RestoreMemoryProtection((uptr)absolute_target_ptr, sizeof(uptr),
+ protection))
+ return false;
+
+ return true;
+ }
+# endif
+
// Check whether the first instruction is a relative jump.
if (*(u8*)old_func != 0xE9)
return false;
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h b/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h
index c694897b6556b..c4bfee6c479e3 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h
@@ -63,10 +63,10 @@
// For example:
// SANITIZER_INTERFACE_WEAK_DEF(bool, compare, int a, int b) { return a > b; }
//
-#if SANITIZER_WINDOWS
-#include "sanitizer_win_defs.h"
-# define SANITIZER_INTERFACE_WEAK_DEF(ReturnType, Name, ...) \
- WIN_WEAK_EXPORT_DEF(ReturnType, Name, __VA_ARGS__)
+#if SANITIZER_WINDOWS && (!defined(__GNUC__) || defined(__clang__))
+# include "sanitizer_win_defs.h"
+# define SANITIZER_INTERFACE_WEAK_DEF(ReturnType, Name, ...) \
+ WIN_WEAK_EXPORT_DEF(ReturnType, Name, __VA_ARGS__)
#else
# define SANITIZER_INTERFACE_WEAK_DEF(ReturnType, Name, ...) \
extern "C" SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE \
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp
index 3a1d1257a3481..4c4b5cf964256 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp
@@ -759,9 +759,11 @@ static int RunAtexit() {
return ret;
}
-#pragma section(".CRT$XID", long, read)
-__declspec(allocate(".CRT$XID")) int (*__run_atexit)() = RunAtexit;
-#endif
+# if !defined(__GNUC__) || defined(__clang__)
+# pragma section(".CRT$XID", long, read)
+# endif
+IN_SECTION(".CRT$XID") int (*__run_atexit)() = RunAtexit;
+# endif
// ------------------ sanitizer_libc.h
fd_t OpenFile(const char *filename, FileAccessMode mode, error_t *last_error) {
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_win_defs.h b/compiler-rt/lib/sanitizer_common/sanitizer_win_defs.h
index bfe38a3323674..e25dedb3d2fbb 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_win_defs.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_win_defs.h
@@ -43,7 +43,13 @@
#define STRINGIFY_(A) #A
#define STRINGIFY(A) STRINGIFY_(A)
-#if !SANITIZER_GO
+# if !defined(__GNUC__) || defined(__clang__)
+# define IN_SECTION(n) __declspec(allocate(n))
+# else
+# define IN_SECTION(n) __attribute__((section(n)))
+# endif
+
+# if !SANITIZER_GO && defined(__clang__)
// ----------------- A workaround for the absence of weak symbols --------------
// We don't have a direct equivalent of weak symbols when using MSVC, but we can
@@ -161,14 +167,24 @@
// }
//
-#else // SANITIZER_GO
+# elif !SANITIZER_GO
+
+# define WIN_FORCE_LINK(Name) \
+ extern "C" __typeof__(Name) Name; \
+ static __attribute__((used)) __typeof__(&Name) __force_link_##Name = \
+ &Name;
+
+# define WIN_WEAK_EXPORT_DEF(ReturnType, Name, ...) \
+ extern "C" __attribute__((dllexport)) ReturnType Name(__VA_ARGS__)
+
+# else // SANITIZER_GO
// Go neither needs nor wants weak references.
// The shenanigans above don't work for gcc.
-# define WIN_WEAK_EXPORT_DEF(ReturnType, Name, ...) \
- extern "C" ReturnType Name(__VA_ARGS__)
+# define WIN_WEAK_EXPORT_DEF(ReturnType, Name, ...) \
+ extern "C" ReturnType Name(__VA_ARGS__)
-#endif // SANITIZER_GO
+# endif // SANITIZER_GO
#endif // SANITIZER_WINDOWS
#endif // SANITIZER_WIN_DEFS_H
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.cpp
index 16ba155630b0a..794f61fd34418 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.cpp
@@ -61,14 +61,11 @@ void initialize_thunks(const sanitizer_thunk *first,
# pragma section(".WEAK$Z", read) // weak end
extern "C" {
-__declspec(allocate(
- ".INTR$A")) sanitizer_thunk __sanitizer_intercept_thunk_begin;
-__declspec(allocate(".INTR$Z")) sanitizer_thunk __sanitizer_intercept_thunk_end;
-
-__declspec(allocate(
- ".WEAK$A")) sanitizer_thunk __sanitizer_register_weak_thunk_begin;
-__declspec(allocate(
- ".WEAK$Z")) sanitizer_thunk __sanitizer_register_weak_thunk_end;
+IN_SECTION(".INTR$A") sanitizer_thunk __sanitizer_intercept_thunk_begin;
+IN_SECTION(".INTR$Z") sanitizer_thunk __sanitizer_intercept_thunk_end;
+
+IN_SECTION(".WEAK$A") sanitizer_thunk __sanitizer_register_weak_thunk_begin;
+IN_SECTION(".WEAK$Z") sanitizer_thunk __sanitizer_register_weak_thunk_end;
}
extern "C" int __sanitizer_thunk_init() {
@@ -92,8 +89,9 @@ extern "C" int __sanitizer_thunk_init() {
// We want to call dll_thunk_init before C/C++ initializers / constructors are
// executed, otherwise functions like memset might be invoked.
# pragma section(".CRT$XIB", long, read)
-__declspec(allocate(".CRT$XIB")) int (*__sanitizer_thunk_init_ptr)() =
+extern "C" IN_SECTION(".CRT$XIB") int (*__sanitizer_thunk_init_ptr)() =
__sanitizer_thunk_init;
+WIN_FORCE_LINK(__sanitizer_thunk_init_ptr)
static void WINAPI sanitizer_thunk_thread_init(void *mod, unsigned long reason,
void *reserved) {
@@ -102,9 +100,9 @@ static void WINAPI sanitizer_thunk_thread_init(void *mod, unsigned long reason,
}
# pragma section(".CRT$XLAB", long, read)
-__declspec(allocate(".CRT$XLAB")) void(
- WINAPI *__sanitizer_thunk_thread_init_ptr)(void *, unsigned long, void *) =
+extern "C" IN_SECTION(".CRT$XLAB") void(
+ WINAPI* __sanitizer_thunk_thread_init_ptr)(void*, unsigned long, void*) =
sanitizer_thunk_thread_init;
-
+WIN_FORCE_LINK(__sanitizer_thunk_thread_init_ptr)
#endif // defined(SANITIZER_STATIC_RUNTIME_THUNK) ||
- // defined(SANITIZER_DYNAMIC_RUNTIME_THUNK)
\ No newline at end of file
+ // defined(SANITIZER_DYNAMIC_RUNTIME_THUNK)
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.h b/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.h
index 278450d68ac51..492ef6b2b98b2 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_win_thunk_interception.h
@@ -14,6 +14,7 @@
#include <stdint.h>
#include "sanitizer_internal_defs.h"
+#include "sanitizer_win_defs.h"
extern "C" {
__declspec(dllimport) bool __cdecl __sanitizer_override_function(
@@ -53,8 +54,8 @@ void initialize_thunks(const sanitizer_thunk *begin,
sanitizer_export, \
reinterpret_cast<__sanitizer::uptr>(local_function)); \
} \
- __pragma(section(".INTR$M", long, read)) __declspec(allocate( \
- ".INTR$M")) int (*__sanitizer_static_thunk_##local_function)() = \
+ __pragma(section(".INTR$M", long, read)) IN_SECTION(".INTR$M") int ( \
+ *__sanitizer_static_thunk_##local_function)() = \
intercept_##local_function;
// ------------------ Weak symbol registration macros ---------------------- //
@@ -68,21 +69,28 @@ void initialize_thunks(const sanitizer_thunk *begin,
# define REGISTER_WEAK_FUNCTION_ADDRESS(fn) &fn
#endif
-#define REGISTER_WEAK_FUNCTION(local_function) \
- extern "C" void local_function(); \
- extern "C" void WEAK_EXPORT_NAME(local_function)(); \
- WIN_WEAK_IMPORT_DEF(local_function) \
- REGISTER_WEAK_OPTNONE static int register_weak_##local_function() { \
- if ((uintptr_t)REGISTER_WEAK_FUNCTION_ADDRESS(local_function) != \
- (uintptr_t)REGISTER_WEAK_FUNCTION_ADDRESS( \
- WEAK_EXPORT_NAME(local_function))) { \
- return __sanitizer::register_weak( \
- SANITIZER_STRINGIFY(WEAK_EXPORT_NAME(local_function)), \
- reinterpret_cast<__sanitizer::uptr>(local_function)); \
- } \
- return 0; \
- } \
- __pragma(section(".WEAK$M", long, read)) __declspec(allocate( \
- ".WEAK$M")) int (*__sanitizer_register_weak_##local_function)() = \
- register_weak_##local_function;
-#endif // SANITIZER_WIN_STATIC_RUNTIME_THUNK_H
+#if !defined(__GNUC__) || defined(__clang__)
+# define REGISTER_WEAK_FUNCTION(local_function) \
+ extern "C" void local_function(); \
+ extern "C" void WEAK_EXPORT_NAME(local_function)(); \
+ WIN_WEAK_IMPORT_DEF(local_function) \
+ REGISTER_WEAK_OPTNONE static int register_weak_##local_function() { \
+ if ((uintptr_t)REGISTER_WEAK_FUNCTION_ADDRESS(local_function) != \
+ (uintptr_t)REGISTER_WEAK_FUNCTION_ADDRESS( \
+ WEAK_EXPORT_NAME(local_function))) { \
+ return __sanitizer::register_weak( \
+ SANITIZER_STRINGIFY(WEAK_EXPORT_NAME(local_function)), \
+ reinterpret_cast<__sanitizer::uptr>(local_function)); \
+ } \
+ return 0; \
+ } \
+ __pragma(section(".WEAK$M", long, read)) __declspec(allocate( \
+ ".WEAK$M")) int (*__sanitizer_register_weak_##local_function)() = \
+ register_weak_##local_function;
+#else
+// GNU ld does not support /alternatename. User overrides of weak sanitizer
+// functions are not forwarded to the sanitizer DLL on this toolchain.
+# define REGISTER_WEAK_FUNCTION(local_function) \
+ extern "C" void local_function();
+#endif
+#endif // SANITIZER_WIN_THUNK_INTERCEPTION_H
diff --git a/compiler-rt/lib/ubsan/ubsan_handlers.cpp b/compiler-rt/lib/ubsan/ubsan_handlers.cpp
index 2614d49bf238b..38e156b85489c 100644
--- a/compiler-rt/lib/ubsan/ubsan_handlers.cpp
+++ b/compiler-rt/lib/ubsan/ubsan_handlers.cpp
@@ -927,7 +927,7 @@ static void handleCFIBadIcall(CFICheckFailData *Data, ValueHandle Function,
namespace __ubsan {
-#ifdef _WIN32
+#if defined(_WIN32) && (!defined(__GNUC__) || defined(__clang__))
extern "C" void __ubsan_handle_cfi_bad_type_default(CFICheckFailData *Data,
ValueHandle Vtable,
bool ValidVtable,
@@ -936,6 +936,11 @@ extern "C" void __ubsan_handle_cfi_bad_type_default(CFICheckFailData *Data,
}
WIN_WEAK_ALIAS(__ubsan_handle_cfi_bad_type, __ubsan_handle_cfi_bad_type_default)
+void __ubsan_handle_cfi_bad_type(CFICheckFailData *Data, ValueHandle Vtable,
+ bool ValidVtable, ReportOptions Opts);
+#elif defined(_WIN32)
+// GNU ld does not support /alternatename. The real implementation lives in
+// ubsan_handlers_cxx.cpp.
void __ubsan_handle_cfi_bad_type(CFICheckFailData *Data, ValueHandle Vtable,
bool ValidVtable, ReportOptions Opts);
#else
>From 9cfae7205066537b476dc3b9ab1dc2fdf4666e29 Mon Sep 17 00:00:00 2001
From: Oleg Tolmatcev <oleg.tolmatcev at gmail.com>
Date: Wed, 15 Jul 2026 18:09:46 +0200
Subject: [PATCH 2/3] [compiler-rt] Adjust ASan Windows tests for mingw-w64
Update the Windows ASan tests for the mingw-w64 configuration.
---
.../test/asan/TestCases/Windows/fuse-lld.cpp | 10 ++++++----
.../test/asan/TestCases/Windows/unsymbolized.cpp | 16 +++++++++++-----
2 files changed, 17 insertions(+), 9 deletions(-)
diff --git a/compiler-rt/test/asan/TestCases/Windows/fuse-lld.cpp b/compiler-rt/test/asan/TestCases/Windows/fuse-lld.cpp
index 5fa5945df4dc0..b689b403fcb92 100644
--- a/compiler-rt/test/asan/TestCases/Windows/fuse-lld.cpp
+++ b/compiler-rt/test/asan/TestCases/Windows/fuse-lld.cpp
@@ -2,8 +2,8 @@
//
// REQUIRES: lld-available
//
-// RUN: %clangxx_asan -O2 %s -o %t.exe -g -gcodeview -fuse-ld=lld -Wl,-debug
-// RUN: not %run %t.exe 2>&1 | FileCheck %s
+// RUN: %clangxx_asan %if target={{.*-windows-gnu}} %{ -gcodeview -gcolumn-info -Wl,--pdb= %} %else %{ -g -gcodeview -Wl,-debug %} -O2 %s -o %t.exe -fuse-ld=lld
+// RUN: not %run %t.exe 2>&1 | FileCheck %s --check-prefixes=CHECK,%if target={{.*-windows-msvc.*}} %{MSVC%} %else %{MINGW%}
#include <stdlib.h>
@@ -13,7 +13,9 @@ int main() {
return x[5];
// CHECK: heap-use-after-free
// CHECK: free
- // CHECK: main{{.*}}fuse-lld.cpp:[[@LINE-4]]:3
+ // MSVC: main{{.*}}fuse-lld.cpp:[[@LINE-4]]:3
+ // MINGW: {{.*fuse-lld.cpp.tmp.exe\+0x14000[0-9a-f]+}}
// CHECK: malloc
- // CHECK: main{{.*}}fuse-lld.cpp:[[@LINE-7]]:20
+ // MSVC: main{{.*}}fuse-lld.cpp:[[@LINE-8]]:20
+ // MINGW: {{.*fuse-lld.cpp.tmp.exe\+0x14000[0-9a-f]+}}
}
diff --git a/compiler-rt/test/asan/TestCases/Windows/unsymbolized.cpp b/compiler-rt/test/asan/TestCases/Windows/unsymbolized.cpp
index ade5e5b914be8..29c9c3f7f15b9 100644
--- a/compiler-rt/test/asan/TestCases/Windows/unsymbolized.cpp
+++ b/compiler-rt/test/asan/TestCases/Windows/unsymbolized.cpp
@@ -3,9 +3,13 @@
// which is the default image base of an executable.
// RUN: rm -f %t.pdb
-// RUN: %clangxx_asan -c -O2 %s -o %t.obj
-// RUN: lld-link /nologo /OUT:%t.exe %t.obj -defaultlib:libcmt -nodefaultlib:msvcrt -defaultlib:oldnames %asan_static_runtime_thunk %asan_lib
-// RUN: not %run %t.exe 2>&1 | FileCheck %s
+// RUN: %if target={{.*-windows-gnu}} %{ \
+// RUN: %clangxx_asan -O2 %s -o %t.exe -gcodeview -gcolumn-info -fuse-ld=lld \
+// RUN: %} %else %{ \
+// RUN: %clangxx_asan -c -O2 %s -o %t.obj && \
+// RUN: lld-link /nologo /OUT:%t.exe %t.obj -defaultlib:libcmt -nodefaultlib:msvcrt -defaultlib:oldnames %asan_static_runtime_thunk %asan_lib \
+// RUN: %}
+// RUN: not %run %t.exe 2>&1 | FileCheck %s --check-prefixes=CHECK,%if target={{.*-windows-msvc.*}} %{MSVC%} %else %{MINGW%}
// REQUIRES: lld-available
#include "../defines.h"
@@ -22,6 +26,8 @@ int do_uaf(void) {
free(x);
return x[5];
// CHECK: AddressSanitizer: heap-use-after-free
- // CHECK: #0 {{0x[a-f0-9]+ \(.*[\\/]unsymbolized.cpp.*.exe\+(0x40|0x14000)[a-f0-9]{4}\)}}
- // CHECK: #1 {{0x[a-f0-9]+ \(.*[\\/]unsymbolized.cpp.*.exe\+(0x40|0x14000)[a-f0-9]{4}\)}}
+ // MSVC: #0 {{0x[a-f0-9]+ \(.*[\\/]unsymbolized.cpp.*.exe\+(0x40|0x14000)[a-f0-9]{4}\)}}
+ // MSVC: #1 {{0x[a-f0-9]+ \(.*[\\/]unsymbolized.cpp.*.exe\+(0x40|0x14000)[a-f0-9]{4}\)}}
+ // MINGW: #0 {{0x[a-f0-9]+ in do_uaf\(\) \(.*[\\/]unsymbolized.cpp.*.exe\+0x14000[a-f0-9]{4}\)}}
+ // MINGW: #1 {{0x[a-f0-9]+ in main \(.*[\\/]unsymbolized.cpp.*.exe\+0x14000[a-f0-9]{4}\)}}
}
>From 7db83fffba20fe6cac82301844d780011c191f26 Mon Sep 17 00:00:00 2001
From: Oleg Tolmatcev <oleg.tolmatcev at gmail.com>
Date: Thu, 16 Jul 2026 20:31:12 +0200
Subject: [PATCH 3/3] [compiler-rt] Add libbacktrace support on Windows
---
.../sanitizer_symbolizer_libbacktrace.cpp | 16 ++++++++--------
.../sanitizer_symbolizer_win.cpp | 8 ++++++++
2 files changed, 16 insertions(+), 8 deletions(-)
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libbacktrace.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libbacktrace.cpp
index d78dab93487f1..849e5ee475eb5 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libbacktrace.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libbacktrace.cpp
@@ -19,15 +19,15 @@
#if SANITIZER_LIBBACKTRACE
# include "backtrace-supported.h"
-# if SANITIZER_POSIX && BACKTRACE_SUPPORTED && !BACKTRACE_USES_MALLOC
-# include "backtrace.h"
-# if SANITIZER_CP_DEMANGLE
-# undef ARRAY_SIZE
-# include "demangle.h"
+# if BACKTRACE_SUPPORTED && !BACKTRACE_USES_MALLOC
+# include "backtrace.h"
+# if SANITIZER_CP_DEMANGLE
+# undef ARRAY_SIZE
+# include "demangle.h"
+# endif
+# else
+# define SANITIZER_LIBBACKTRACE 0
# endif
-# else
-# define SANITIZER_LIBBACKTRACE 0
-# endif
#endif
namespace __sanitizer {
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp
index 1ff8b8f1bab48..af6639d740f49 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp
@@ -16,6 +16,7 @@
# include "sanitizer_dbghelp.h"
# include "sanitizer_symbolizer_internal.h"
+# include "sanitizer_symbolizer_libbacktrace.h"
namespace __sanitizer {
@@ -279,6 +280,12 @@ static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
return;
}
+# if defined(__GNUC__) && !defined(__clang__)
+ if (SymbolizerTool* tool = LibbacktraceSymbolizer::get(allocator)) {
+ VReport(2, "Using libbacktrace symbolizer.\n");
+ list->push_back(tool);
+ }
+# else
// Add llvm-symbolizer.
const char *user_path = common_flags()->external_symbolizer_path;
@@ -301,6 +308,7 @@ static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
} else {
VReport(2, "External symbolizer is not present.\n");
}
+# endif
// Add the dbghelp based symbolizer.
list->push_back(new(*allocator) WinSymbolizerTool());
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