--- a/include/SDL_mutex.h Thu Jun 13 21:40:18 2002 +0000
+++ b/include/SDL_mutex.h Thu Jun 13 23:59:20 2002 +0000
@@ -66,7 +66,10 @@
#define SDL_LockMutex(m) SDL_mutexP(m)
extern DECLSPEC int SDLCALL SDL_mutexP(SDL_mutex *mutex);
-/* Unlock the mutex (Returns 0, or -1 on error) */
+/* Unlock the mutex (Returns 0, or -1 on error)
+ It is an error to unlock a mutex that has not been locked by
+ the current thread, and doing so results in undefined behavior.
+ */
#define SDL_UnlockMutex(m) SDL_mutexV(m)
extern DECLSPEC int SDLCALL SDL_mutexV(SDL_mutex *mutex);