Fixed bug #741

The thread ID is an unsigned long so it can hold pthread_t so people can do naughty things with it.

I'm going to be adding additional useful thread API functions, but this should prevent crashes in people's existing code on 64-bit architectures.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%404327

test/testerror.c

@@ -22,7 +22,7 @@ int SDLCALL
 ThreadFunc(void *data)
 {
     /* Set the child thread error string */
-    SDL_SetError("Thread %s (%d) had a problem: %s",
+    SDL_SetError("Thread %s (%lu) had a problem: %s",
                  (char *) data, SDL_ThreadID(), "nevermind");
     while (alive) {
         printf("Thread '%s' is alive!\n", (char *) data);