Rework Win32 mutex, condition variable and once flag (#2111)

* Rework Win32 mutex, condition variable and once flag.

lib/std/os/win32/general.c3

@@ -222,4 +222,5 @@ const Win32_DWORD ERROR_MR_MID_NOT_FOUND = 0x13D;
 const Win32_DWORD ERROR_SCOPE_NOT_FOUND = 0x13E;
 const Win32_DWORD ERROR_UNDEFINED_SCOPE = 0x13F;
 const Win32_DWORD ERROR_IO_INCOMPLETE = 0x3E4;
-const Win32_DWORD ERROR_IO_PENDING = 0x3E5;
+const Win32_DWORD ERROR_IO_PENDING = 0x3E5;
+const Win32_DWORD ERROR_TIMEOUT = 0x5B4;

lib/std/os/win32/process.c3

@@ -46,6 +46,8 @@ const IMAGE_FILE_MACHINE_ARM64 = 0xAA64;
 const IMAGE_FILE_MACHINE_AMD64 = 0x8664;
 const UNDNAME_COMPLETE = 0x0000;
 
+alias Win32_INIT_ONCE_FN = fn Win32_BOOL(Win32_INIT_ONCE* initOnce, void* parameter, void** context);
+
 extern fn void initializeCriticalSection(Win32_CRITICAL_SECTION* section) @extern("InitializeCriticalSection");
 extern fn void deleteCriticalSection(Win32_CRITICAL_SECTION* section) @extern("DeleteCriticalSection");
 extern fn Win32_HANDLE createMutex(void*, Win32_BOOL, void*) @extern("CreateMutexA");
@@ -53,6 +55,19 @@ extern fn Win32_BOOL releaseMutex(Win32_HANDLE) @extern("ReleaseMutex");
 extern fn void enterCriticalSection(Win32_CRITICAL_SECTION* section) @extern("EnterCriticalSection");
 extern fn void leaveCriticalSection(Win32_CRITICAL_SECTION* section) @extern("LeaveCriticalSection");
 extern fn Win32_BOOL tryEnterCriticalSection(Win32_CRITICAL_SECTION* section) @extern("TryEnterCriticalSection");
+extern fn void initializeSRWLock(Win32_SRWLOCK* lock) @extern("InitializeSRWLock");
+extern fn void acquireSRWLockExclusive(Win32_SRWLOCK* lock) @extern("AcquireSRWLockExclusive");
+extern fn void acquireSRWLockShared(Win32_SRWLOCK* lock) @extern("AcquireSRWLockShared");
+extern fn void releaseSRWLockExclusive(Win32_SRWLOCK* lock) @extern("ReleaseSRWLockExclusive");
+extern fn void releaseSRWLockShared(Win32_SRWLOCK* lock) @extern("ReleaseSRWLockShared");
+extern fn Win32_BOOL tryAcquireSRWLockExclusive(Win32_SRWLOCK* lock) @extern("TryAcquireSRWLockExclusive");
+extern fn Win32_BOOL tryAcquireSRWLockShared(Win32_SRWLOCK* lock) @extern("TryAcquireSRWLockShared");
+extern fn void initializeConditionVariable(Win32_CONDITION_VARIABLE* conditionVariable) @extern("InitializeConditionVariable");
+extern fn void wakeConditionVariable(Win32_CONDITION_VARIABLE* conditionVariable) @extern("WakeConditionVariable");
+extern fn void wakeAllConditionVariable(Win32_CONDITION_VARIABLE* conditionVariable) @extern("WakeAllConditionVariable");
+extern fn Win32_BOOL sleepConditionVariableCS(Win32_CONDITION_VARIABLE* conditionVariable, Win32_CRITICAL_SECTION* section, Win32_DWORD dwMilliseconds) @extern("SleepConditionVariableCS");
+extern fn Win32_BOOL sleepConditionVariableSRW(Win32_CONDITION_VARIABLE* conditionVariable, Win32_SRWLOCK* lock, Win32_DWORD dwMilliseconds, Win32_ULONG flags) @extern("SleepConditionVariableSRW");
+extern fn Win32_BOOL initOnceExecuteOnce(Win32_INIT_ONCE* initOnce, Win32_INIT_ONCE_FN initFn, void* parameter, void** context) @extern("InitOnceExecuteOnce");
 extern fn Win32_DWORD waitForSingleObject(Win32_HANDLE hHandle, Win32_DWORD dwMilliseconds) @extern("WaitForSingleObject");
 extern fn Win32_DWORD waitForSingleObjectEx(Win32_HANDLE hHandle, Win32_DWORD dwMilliseconds, Win32_BOOL bAlertable) @extern("WaitForSingleObjectEx");
 extern fn Win32_DWORD waitForMultipleObjects(Win32_DWORD nCount, Win32_HANDLE* lpHandles, Win32_BOOL bWaitAll, Win32_DWORD dwMilliseconds) @extern("WaitForMultipleObjects");

lib/std/os/win32/types.c3

@@ -190,6 +190,9 @@ union Win32_LARGE_INTEGER
 }
 
 typedef Win32_CRITICAL_SECTION = ulong[5];
+typedef Win32_CONDITION_VARIABLE = void*;
+typedef Win32_SRWLOCK = void*;
+typedef Win32_INIT_ONCE = void*;
 
 struct Win32_SECURITY_ATTRIBUTES
 {
@@ -694,4 +697,3 @@ alias Win32_LPSTACKFRAME64 = Win32_STACKFRAME64*;
 alias Win32_PMODLOAD_DATA = Win32_MODLOAD_DATA*;
 alias Win32_PIMAGEHLP_LINE64 = Win32_IMAGEHLP_LINE64*;
 alias Win32_LPMODULEINFO = Win32_MODULEINFO*;
-

lib/std/threads/os/thread_none.c3

@@ -1,6 +1,7 @@
 module std::thread::os @if (!env::POSIX && !env::WIN32);
 
 typedef NativeMutex = int;
+typedef NativeTimedMutex = int;
 typedef NativeConditionVariable = int;
 typedef NativeOnceFlag = int;
 typedef NativeThread = int;

lib/std/threads/os/thread_posix.c3

@@ -7,6 +7,8 @@ struct NativeMutex
 	bool initialized;
 }
 
+alias NativeTimedMutex = NativeMutex;
+
 alias NativeConditionVariable = Pthread_cond_t;
 
 struct NativeThread
@@ -28,7 +30,7 @@ fn void? NativeMutex.init(&self, MutexType type)
 	if (posix::pthread_mutexattr_init(&attr)) return thread::INIT_FAILED?;
 	defer posix::pthread_mutexattr_destroy(&attr);
 	// TODO: make a fine grained error instead
-	if (type & thread::MUTEX_RECURSIVE)
+	if (type.recursive)
 	{
 		if (posix::pthread_mutexattr_settype(&attr, posix::PTHREAD_MUTEX_RECURSIVE)) return thread::INIT_FAILED?;
 	}

lib/std/threads/os/thread_win32.c3

@@ -5,239 +5,313 @@ typedef NativeThread = inline Win32_HANDLE;
 
 struct NativeMutex
 {
-	union
+	Win32_SRWLOCK srw_lock;
+	Win32_DWORD owner_thread;
+	bitstruct : uint
 	{
-		Win32_CRITICAL_SECTION critical_section;
-		Win32_HANDLE handle;
+		bool initialized : 0;
+		bool recursive   : 1;
+		uint locks       : 2..31;
 	}
-	// Size is less than a Win32_HANDLE so due to alignment
-	// there is no benefit to pack these into a bitstruct.
-	uint locks;
-	bool recursive;
-	bool timed;
 }
 
-struct NativeOnceFlag
+struct NativeTimedMutex
 {
-	int status;
-	Win32_CRITICAL_SECTION lock;
+	Win32_SRWLOCK srw_lock;
+	Win32_CONDITION_VARIABLE cond_var;
+	Win32_DWORD owner_thread;
+	bitstruct : uint
+	{
+		bool initialized : 0;
+		bool recursive   : 1;
+		uint locks       : 2..31;
+	}
 }
 
 struct NativeConditionVariable
 {
-	union
-	{
-		struct
-		{
-			Win32_HANDLE event_one;
-			Win32_HANDLE event_all;
-		}
-		Win32_HANDLE[2] events;
-	}
-	uint waiters_count;
-	Win32_CRITICAL_SECTION waiters_count_lock;
+	Win32_CONDITION_VARIABLE cond_var;
 }
 
-fn void? NativeMutex.init(&mtx, MutexType type)
+struct NativeOnceFlag
 {
-	mtx.locks = 0;
-	mtx.recursive = (bool)(type & thread::MUTEX_RECURSIVE);
-	mtx.timed = (bool)(type & thread::MUTEX_TIMED);
-	if (!mtx.timed)
-	{
-		win32::initializeCriticalSection(&(mtx.critical_section));
-		return;
-	}
-	if (!(mtx.handle = win32::createMutex(null, 0, null))) return thread::INIT_FAILED?;
+	Win32_INIT_ONCE init_once;
 }
 
-fn void? NativeMutex.destroy(&mtx)
-{
-	mtx.locks = 0;
-	if (!mtx.timed)
-	{
-		win32::deleteCriticalSection(&mtx.critical_section);
-		return;
-	}
-	if (!win32::closeHandle(mtx.handle)) return thread::DESTROY_FAILED?;
-}
-
-fn void? NativeMutex.lock(&mtx)
-{
-	if (!mtx.timed)
-	{
-		win32::enterCriticalSection(&mtx.critical_section);
-	}
-	else
-	{
-		switch (win32::waitForSingleObject(mtx.handle, win32::INFINITE))
-		{
-			case win32::WAIT_OBJECT_0:
-				break;
-			case win32::WAIT_ABANDONED:
-			default:
-				return thread::LOCK_FAILED?;
-
-		}
-	}
-	if (!mtx.recursive && mtx.locks)
-	{
-		return thread::LOCK_FAILED?;
-	}
-	mtx.locks++;
-}
-
-
 <*
- @require mtx.timed : "Only available for timed locks"
+ @require !mtx.initialized : "Mutex is already initialized"
+ @require !type.timed
+ @ensure mtx.initialized
 *>
-fn void? NativeMutex.lock_timeout(&mtx, ulong ms)
+fn void? NativeMutex.init(&mtx, MutexType type)
 {
-	if (ms > uint.max) ms = uint.max;
-	switch (win32::waitForSingleObject(mtx.handle, (uint)ms))
-	{
-		case win32::WAIT_OBJECT_0:
-			break;
-		case win32::WAIT_TIMEOUT:
-			return thread::LOCK_TIMEOUT?;
-		case win32::WAIT_ABANDONED:
-		default:
-			return thread::LOCK_FAILED?;
-	}
-	if (!mtx.recursive && mtx.locks)
-	{
-		return thread::LOCK_FAILED?;
-	}
-	mtx.locks++;
+	*mtx = {
+		.initialized = true,
+		.recursive = type.recursive,
+	};
 }
 
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+ @require mtx.owner_thread != win32::getCurrentThreadId() : "Mutex was not unlocked before destroying it"
+ @ensure !mtx.initialized
+*>
+fn void? NativeMutex.destroy(&mtx)
+{
+	*mtx = {};
+}
+
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
+fn void? NativeMutex.lock(&mtx)
+{
+	Win32_DWORD current_thread = win32::getCurrentThreadId();
+	if (mtx.owner_thread == current_thread)
+	{
+		if (!mtx.recursive) return thread::LOCK_FAILED?;
+		mtx.locks++;
+		return;
+	}
+
+	win32::acquireSRWLockExclusive(&mtx.srw_lock);
+	mtx.owner_thread = current_thread;
+	mtx.locks = 1;
+}
+
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
 fn bool NativeMutex.try_lock(&mtx)
 {
-	bool success = mtx.timed
-		? win32::waitForSingleObject(mtx.handle, 0) == win32::WAIT_OBJECT_0
-		: (bool)win32::tryEnterCriticalSection(&mtx.critical_section);
-
-	if (!success) return false;
-	if (!mtx.recursive)
+	Win32_DWORD current_thread = win32::getCurrentThreadId();
+	if (mtx.owner_thread == current_thread)
 	{
-		if (mtx.locks)
-		{
-			if (mtx.timed)
-			{
-				win32::releaseMutex(mtx.handle);
-			}
-			else
-			{
-				win32::leaveCriticalSection(&mtx.critical_section);
-			}
-			return false;
-		}
+		if (!mtx.recursive) return false;
+		mtx.locks++;
+		return true;
 	}
-	mtx.locks++;
+
+	if (!win32::tryAcquireSRWLockExclusive(&mtx.srw_lock)) return false;
+
+	mtx.owner_thread = current_thread;
+	mtx.locks = 1;
 	return true;
 }
 
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
 fn void? NativeMutex.unlock(&mtx)
 {
-	if (!mtx.locks) return thread::UNLOCK_FAILED?;
-	mtx.locks--;
-	if (!mtx.timed)
+	$if env::COMPILER_SAFE_MODE:
+		if (mtx.owner_thread != win32::getCurrentThreadId()) return thread::UNLOCK_FAILED?; // Mutex was not locked by the current thread
+	$endif
+	if (--mtx.locks == 0)
 	{
-		win32::leaveCriticalSection(&mtx.critical_section);
-		return;
+		mtx.owner_thread = 0;
+		win32::releaseSRWLockExclusive(&mtx.srw_lock);
 	}
-	if (!win32::releaseMutex(mtx.handle)) return thread::UNLOCK_FAILED?;
 }
 
-const int CONDITION_EVENT_ONE = 0;
-const int CONDITION_EVENT_ALL = 1;
+<*
+ @require type.timed
+ @require !mtx.initialized : "Mutex is already initialized"
+ @ensure mtx.initialized
+*>
+fn void? NativeTimedMutex.init(&mtx, MutexType type)
+{
+	*mtx = {
+		.initialized = true,
+		.recursive = type.recursive,
+	};
+}
+
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+ @require mtx.owner_thread != win32::getCurrentThreadId() : "Mutex was not unlocked before destroying it"
+ @ensure !mtx.initialized
+*>
+fn void? NativeTimedMutex.destroy(&mtx)
+{
+	*mtx = {};
+}
+
+fn void? NativeTimedMutex.wait_cond_var(&mtx, uint ms) @local
+{
+	if (!win32::sleepConditionVariableSRW(&mtx.cond_var, &mtx.srw_lock, ms, 0))
+	{
+		if (win32::getLastError() != win32::ERROR_TIMEOUT)
+		{
+			return thread::WAIT_FAILED?;
+		}
+	}
+}
+
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
+fn void? NativeTimedMutex.lock(&mtx)
+{
+	Win32_DWORD current_thread = win32::getCurrentThreadId();
+	if (mtx.owner_thread == current_thread)
+	{
+		if (!mtx.recursive) return thread::LOCK_FAILED?;
+		mtx.locks++;
+		return;
+	}
+
+	win32::acquireSRWLockExclusive(&mtx.srw_lock);
+	defer win32::releaseSRWLockExclusive(&mtx.srw_lock);
+
+	while (mtx.locks)
+	{
+		mtx.wait_cond_var(win32::INFINITE)!;
+	}
+	mtx.locks = 1;
+	mtx.owner_thread = current_thread;
+}
+
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
+fn void? NativeTimedMutex.lock_timeout(&mtx, ulong ms)
+{
+	Win32_DWORD current_thread = win32::getCurrentThreadId();
+	if (mtx.owner_thread == current_thread)
+	{
+		if (!mtx.recursive) return thread::LOCK_FAILED?;
+		mtx.locks++;
+		return;
+	}
+
+	win32::acquireSRWLockExclusive(&mtx.srw_lock);
+	defer win32::releaseSRWLockExclusive(&mtx.srw_lock);
+
+	if (!mtx.locks)
+	{
+		// Got the lock without needing to wait
+		mtx.locks = 1;
+		mtx.owner_thread = current_thread;
+		return;
+	}
+
+	NanoDuration duration = time::ms(ms).to_nano();
+	Clock start = clock::now();
+	for (NanoDuration remaining = duration; remaining > 0; remaining = duration - start.to_now())
+	{
+		ulong remaining_ms = remaining.to_ms();
+		if (remaining_ms > uint.max) remaining_ms = uint.max;
+		mtx.wait_cond_var((uint)remaining_ms)!;
+		if (!mtx.locks)
+		{
+			// Got the lock
+			mtx.locks = 1;
+			mtx.owner_thread = current_thread;
+			return;
+		}
+	}
+	return thread::WAIT_FAILED?;
+}
+
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
+fn bool NativeTimedMutex.try_lock(&mtx)
+{
+	Win32_DWORD current_thread = win32::getCurrentThreadId();
+	if (mtx.owner_thread == current_thread)
+	{
+		if (!mtx.recursive) return false;
+		mtx.locks++;
+		return true;
+	}
+
+	win32::acquireSRWLockExclusive(&mtx.srw_lock);
+	defer win32::releaseSRWLockExclusive(&mtx.srw_lock);
+
+	if (mtx.locks) return false;
+	mtx.locks = 1;
+	mtx.owner_thread = current_thread;
+	return true;
+}
+
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
+fn void? NativeTimedMutex.unlock(&mtx)
+{
+	win32::acquireSRWLockExclusive(&mtx.srw_lock);
+	$if env::COMPILER_SAFE_MODE:
+		if (mtx.owner_thread != win32::getCurrentThreadId()) 
+		{
+			win32::releaseSRWLockExclusive(&mtx.srw_lock);
+			return thread::UNLOCK_FAILED?; // Mutex was not locked by the current thread
+		}
+	$endif
+
+	bool signal;
+	if (--mtx.locks == 0)
+	{
+		mtx.owner_thread = 0;
+		signal = true;
+	}
+	win32::releaseSRWLockExclusive(&mtx.srw_lock);
+	if (signal) win32::wakeConditionVariable(&mtx.cond_var);
+}
 
 fn void? NativeConditionVariable.init(&cond)
 {
-	cond.waiters_count = 0;
-	win32::initializeCriticalSection(&cond.waiters_count_lock);
-	cond.event_one = win32::createEventA(null, 0, 0, null);
-	if (!cond.event_one)
-	{
-		cond.event_all = (Win32_HANDLE)0;
-		return thread::INIT_FAILED?;
-	}
-	cond.event_all = win32::createEventA(null, 1, 0, null);
-	if (!cond.event_all)
-	{
-		win32::closeHandle(cond.event_one);
-		cond.event_one = (Win32_HANDLE)0;
-		return thread::INIT_FAILED?;
-	}
+	cond.cond_var = {};
 }
 
 fn void? NativeConditionVariable.destroy(&cond) @maydiscard
 {
-	if (cond.event_one) win32::closeHandle(cond.event_one);
-	if (cond.event_all) win32::closeHandle(cond.event_all);
-	win32::deleteCriticalSection(&cond.waiters_count_lock);
+	// Nothing to do
 }
 
 fn void? NativeConditionVariable.signal(&cond)
 {
-	win32::enterCriticalSection(&cond.waiters_count_lock);
-	bool have_waiters = cond.waiters_count > 0;
-	win32::leaveCriticalSection(&cond.waiters_count_lock);
-	if (have_waiters && !win32::setEvent(cond.event_one)) return thread::SIGNAL_FAILED?;
+	win32::wakeConditionVariable(&cond.cond_var);
 }
 
 fn void? NativeConditionVariable.broadcast(&cond)
 {
-	win32::enterCriticalSection(&cond.waiters_count_lock);
-	bool have_waiters = cond.waiters_count > 0;
-	win32::leaveCriticalSection(&cond.waiters_count_lock);
-	if (have_waiters && !win32::setEvent(cond.event_all)) return thread::SIGNAL_FAILED?;
+	win32::wakeAllConditionVariable(&cond.cond_var);
 }
 
 fn void? timedwait(NativeConditionVariable* cond, NativeMutex* mtx, uint timeout) @private
 {
-	win32::enterCriticalSection(&cond.waiters_count_lock);
-	cond.waiters_count++;
-	win32::leaveCriticalSection(&cond.waiters_count_lock);
-
-	mtx.unlock()!;
-
-	uint result = win32::waitForMultipleObjects(2, &cond.events, 0, timeout);
-	switch (result)
+	Win32_DWORD owner_thread = mtx.owner_thread;
+	if (mtx.locks != 1 || owner_thread != win32::getCurrentThreadId()) return thread::WAIT_FAILED?;
+	mtx.owner_thread = 0;
+	mtx.locks = 0;
+	defer
 	{
-		case win32::WAIT_TIMEOUT:
-			mtx.lock()!;
-			return thread::WAIT_TIMEOUT?;
-		case win32::WAIT_FAILED:
-			mtx.lock()!;
-			return thread::WAIT_FAILED?;
-		default:
-			break;
+		mtx.owner_thread = owner_thread;
+		mtx.locks = 1;
 	}
-
-	win32::enterCriticalSection(&cond.waiters_count_lock);
-	cond.waiters_count--;
-	// If event all && no waiters
-	bool last_waiter = result == 1 && !cond.waiters_count;
-	win32::leaveCriticalSection(&cond.waiters_count_lock);
-
-	if (last_waiter)
+	if (!win32::sleepConditionVariableSRW(&cond.cond_var, &mtx.srw_lock, timeout, 0))
 	{
-		if (!win32::resetEvent(cond.event_all))
+		if (win32::getLastError() == win32::ERROR_TIMEOUT)
 		{
-			mtx.lock()!;
-			return thread::WAIT_FAILED?;
+			return thread::WAIT_TIMEOUT?;
 		}
+		return thread::WAIT_FAILED?;
 	}
-
-	mtx.lock()!;
 }
 
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
 fn void? NativeConditionVariable.wait(&cond, NativeMutex* mtx) @inline
 {
 	return timedwait(cond, mtx, win32::INFINITE) @inline;
 }
 
+<*
+ @require mtx.initialized : "Mutex was not initialized"
+*>
 fn void? NativeConditionVariable.wait_timeout(&cond, NativeMutex* mtx, ulong ms) @inline
 {
 	if (ms > uint.max) ms = uint.max;
@@ -267,30 +341,12 @@ fn void native_thread_yield()
 
 fn void NativeOnceFlag.call_once(&flag, OnceFn func)
 {
-	while (@volatile_load(flag.status) < 3)
+	var callback = fn Win32_BOOL(Win32_INIT_ONCE* init_once, void* parameter, void** context)
 	{
-		switch (@volatile_load(flag.status))
-		{
-			case 0:
-				if (mem::compare_exchange_volatile(&flag.status, 1, 0, AtomicOrdering.SEQ_CONSISTENT, AtomicOrdering.SEQ_CONSISTENT) == 0)
-				{
-					win32::initializeCriticalSection(&flag.lock);
-					win32::enterCriticalSection(&flag.lock);
-					@volatile_store(flag.status, 2);
-					func();
-					@volatile_store(flag.status, 3);
-					win32::leaveCriticalSection(&flag.lock);
-					return;
-				}
-				break;
-			case 1:
-				break;
-			case 2:
-				win32::enterCriticalSection(&flag.lock);
-				win32::leaveCriticalSection(&flag.lock);
-				break;
-		}
-	}
+		((OnceFn)parameter)();
+		return 1;
+	};
+	win32::initOnceExecuteOnce(&flag.init_once, callback, func, null);
 }
 
 fn int? NativeThread.join(thread)

lib/std/threads/thread.c3

@@ -2,16 +2,16 @@ module std::thread;
 import std::thread::os;
 import std::time;
 
-typedef MutexType = int;
-
-const MutexType MUTEX_PLAIN = 0;
-const MutexType MUTEX_TIMED = 1;
-const MutexType MUTEX_RECURSIVE = 2;
+bitstruct MutexType : int
+{
+	bool timed;
+	bool recursive;
+}
 
 typedef Mutex = NativeMutex;
-typedef TimedMutex = inline Mutex;
 typedef RecursiveMutex = inline Mutex;
-typedef TimedRecursiveMutex = inline Mutex;
+typedef TimedMutex = NativeTimedMutex;
+typedef TimedRecursiveMutex = inline TimedMutex;
 typedef ConditionVariable = NativeConditionVariable;
 typedef Thread = inline NativeThread;
 typedef OnceFlag = NativeOnceFlag;
@@ -33,16 +33,21 @@ faultdef
 	INTERRUPTED,
 	CHANNEL_CLOSED;
 
-macro void? Mutex.init(&mutex) => NativeMutex.init((NativeMutex*)mutex, MUTEX_PLAIN);
-macro void? TimedMutex.init(&mutex) => NativeMutex.init((NativeMutex*)mutex, MUTEX_TIMED);
-macro void? RecursiveMutex.init(&mutex) => NativeMutex.init((NativeMutex*)mutex, MUTEX_RECURSIVE);
-macro void? TimedRecursiveMutex.init(&mutex) => NativeMutex.init((NativeMutex*)mutex, MUTEX_TIMED | MUTEX_RECURSIVE);
+macro void? Mutex.init(&mutex) => NativeMutex.init((NativeMutex*)mutex, {});
+macro void? RecursiveMutex.init(&mutex) => NativeMutex.init((NativeMutex*)mutex, {.recursive});
 macro void? Mutex.destroy(&mutex) => NativeMutex.destroy((NativeMutex*)mutex);
 macro void? Mutex.lock(&mutex) => NativeMutex.lock((NativeMutex*)mutex);
-macro void? TimedMutex.lock_timeout(&mutex, ulong ms) => NativeMutex.lock_timeout((NativeMutex*)mutex, ms);
-macro void? TimedRecursiveMutex.lock_timeout(&mutex, ulong ms) => NativeMutex.lock_timeout((NativeMutex*)mutex, ms);
-macro bool Mutex.try_lock(&mutex) => NativeMutex.try_lock((NativeMutex*)mutex);
+macro bool  Mutex.try_lock(&mutex) => NativeMutex.try_lock((NativeMutex*)mutex);
 macro void? Mutex.unlock(&mutex) => NativeMutex.unlock((NativeMutex*)mutex);
+
+macro void? TimedMutex.init(&mutex) => NativeTimedMutex.init((NativeTimedMutex*)mutex, {.timed});
+macro void? TimedRecursiveMutex.init(&mutex) => NativeTimedMutex.init((NativeTimedMutex*)mutex, {.timed, .recursive});
+macro void? TimedMutex.destroy(&mutex) => NativeTimedMutex.destroy((NativeTimedMutex*)mutex);
+macro void? TimedMutex.lock(&mutex) => NativeTimedMutex.lock((NativeTimedMutex*)mutex);
+macro void? TimedMutex.lock_timeout(&mutex, ulong ms) => NativeTimedMutex.lock_timeout((NativeTimedMutex*)mutex, ms);
+macro bool  TimedMutex.try_lock(&mutex) => NativeTimedMutex.try_lock((NativeTimedMutex*)mutex);
+macro void? TimedMutex.unlock(&mutex) => NativeTimedMutex.unlock((NativeTimedMutex*)mutex);
+
 macro void Mutex.@in_lock(&mutex; @body)
 {
 	(void)mutex.lock();

releasenotes.md

@@ -19,6 +19,7 @@
 - Deprecated old inference with slice copy. Copying must now ensure a slicing operator at the end of the right hand side: `foo[1..2] = bar[..]` rather than the old `foo[1..2] = bar`. The old behaviour can be mostly retained with `--use-old-slice-copy`).
 - Added `Enum.lookup` and `Enum.lookup_field`.
 - `c3c build` picks first target rather than the first executable #2105.
+- New Win32 Mutex, ConditionVariable and OnceFlag implementation
 
 ### Fixes
 - Trying to cast an enum to int and back caused the compiler to crash.
@@ -38,6 +39,7 @@
 - `@ensure` should be allowed to read "out" variables. #2107
 - Error message for casting generic to incompatible type does not work properly with nested generics #1953
 - Fixed enum regression after 0.7.0 enum change.
+- ConditionVariable now properly works on Win32
 
 ### Stdlib changes
 - Hash functions for integer vectors and arrays.