diff --git a/src/thread/pthread/SDL_systhread.c b/src/thread/pthread/SDL_systhread.c
index cd11acc67c..5b39e3b1ad 100644
--- a/src/thread/pthread/SDL_systhread.c
+++ b/src/thread/pthread/SDL_systhread.c
@@ -176,7 +176,7 @@ SDL_ThreadID(void)
 
 int SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
 {
-#if __RISCOS__
+#if defined(__RISCOS__)
     /* FIXME: Setting thread priority does not seem to be supported */
     return 0;
 #else