diff --git a/sim_disk.c b/sim_disk.c
index b6768525..5dbbb012 100644
--- a/sim_disk.c
+++ b/sim_disk.c
@@ -2787,7 +2787,7 @@ errno = Status;
 return hVHD;
 }
 
-static
+static void
 ExpandToFullPath (const char *szFileSpec,
                   char *szFullFileSpecBuffer,
                   size_t BufferSize)