diff -urp src.old/winsup/cygwin/thread.cc src/winsup/cygwin/thread.cc
--- src.old/winsup/cygwin/thread.cc	2003-03-19 14:22:24.000000000 +0100
+++ src/winsup/cygwin/thread.cc	2003-03-19 14:27:45.000000000 +0100
@@ -934,11 +934,11 @@ pthread_cond::Wait (pthread_mutex_t mute
   DWORD rv;
 
   mtxIn.Lock ();
-  if (1 == InterlockedIncrement ((long *)&waiting))
+  if (1 == InterlockedIncrementUL (&waiting))
     mtxCond = mutex;
   else if (mtxCond != mutex)
     {
-      InterlockedDecrement ((long *)&waiting);
+      InterlockedDecrementUL (&waiting);
       mtxIn.UnLock ();
       return EINVAL;
     }
@@ -969,7 +969,7 @@ pthread_cond::Wait (pthread_mutex_t mute
         rv = WAIT_OBJECT_0;
     }
 
-  InterlockedDecrement ((long *)&waiting);
+  InterlockedDecrementUL (&waiting);
 
   if (rv == WAIT_OBJECT_0 && 0 == --pending)
     /*
@@ -1596,11 +1596,11 @@ pthread_mutex::_Lock (pthread_t self)
 {
   int result = 0;
 
-  if (1 == InterlockedIncrement ((long *)&lock_counter))
+  if (1 == InterlockedIncrementUL (&lock_counter))
     SetOwner (self);
   else if (PTHREAD_MUTEX_NORMAL != type && pthread_equal (owner, self))
     {
-      InterlockedDecrement ((long *) &lock_counter);
+      InterlockedDecrementUL (&lock_counter);
       if (PTHREAD_MUTEX_RECURSIVE == type)
 	result = LockRecursive ();
       else
@@ -1620,7 +1620,7 @@ pthread_mutex::_TryLock (pthread_t self)
 {
   int result = 0;
 
-  if (0 == InterlockedCompareExchange ((long *)&lock_counter, 1, 0 ))
+  if (0 == InterlockedCompareExchangeUL (&lock_counter, 1, 0 ))
     SetOwner (self);
   else if (PTHREAD_MUTEX_RECURSIVE == type && pthread_equal (owner, self))
     result = LockRecursive ();
@@ -1639,7 +1639,7 @@ pthread_mutex::_UnLock (pthread_t self)
   if (0 == --recursion_counter)
     {
       owner = NULL;
-      if (InterlockedDecrement ((long *)&lock_counter))
+      if (InterlockedDecrementUL (&lock_counter))
 	// Another thread is waiting
 	::ReleaseSemaphore (win32_obj_id, 1, NULL);
     }
diff -urp src.old/winsup/cygwin/winbase.h src/winsup/cygwin/winbase.h
--- src.old/winsup/cygwin/winbase.h	2003-03-19 14:23:15.000000000 +0100
+++ src/winsup/cygwin/winbase.h	2003-03-19 14:25:20.000000000 +0100
@@ -57,6 +57,30 @@ ilockcmpexch (long *t, long v, long c)
 #undef InterlockedCompareExchange
 #define InterlockedCompareExchange ilockcmpexch
 
+extern __inline__ unsigned long
+InterlockedIncrementUL (unsigned long *m)
+{
+  return (unsigned long) InterlockedIncrement ((long*) m);
+}
+
+extern __inline__ unsigned long
+InterlockedDecrementUL(unsigned long *m)
+{
+  return (unsigned long) InterlockedDecrement ((long*) m);
+}
+
+extern __inline__ unsigned long
+InterlockedExchangeUL (unsigned long *t, unsigned long v)
+{
+  return (unsigned long) InterlockedExchange ((long*) t, (long) v);
+}
+
+extern __inline__ unsigned long
+InterlockedCompareExchangeUL(unsigned long *t, unsigned long v, unsigned long c)
+{
+  return (unsigned long) InterlockedCompareExchange ((long*) t, (long) v, (long) c);
+}
+
 #ifndef EXPCGf
 #define DECLARE_TLS_STORAGE do {} while (0)
 #else