diff --git a/src/misc2.c b/src/misc2.c
index 19b99e2..f22bf3f 100644
--- a/src/misc2.c
+++ b/src/misc2.c
@@ -5924,7 +5924,11 @@
 {
     if (emsg_not_now())
 	return TRUE;		/* no error messages at the moment */
+#ifdef HAVE_STDARG_H
+    vim_snprintf((char *)IObuff, IOSIZE, (char *)s, a1, a2);
+#else
     vim_snprintf((char *)IObuff, IOSIZE, (char *)s, (long_u)a1, (long_u)a2);
+#endif
     return emsg(IObuff);
 }