diff --git a/src/thread/switch/SDL_systhread.c b/src/thread/switch/SDL_systhread.c
index e704d3683..b3bd286ed 100644
--- a/src/thread/switch/SDL_systhread.c
+++ b/src/thread/switch/SDL_systhread.c
@@ -33,7 +33,7 @@
 
 #define STACK_SIZE 0x2000
 
-void
+static void
 SDL_SYS_RunThread(void *data)
 {
     SDL_RunThread(data);