--- a/mojoshader_common.c	Wed Apr 01 17:23:22 2020 -0400
+++ b/mojoshader_common.c	Thu Apr 02 15:06:14 2020 -0400
@@ -578,7 +578,7 @@
     // In this case we make another copy of va and fetch the length only
     // with another call to _vscprintf
 
-#ifdef _WIN32
+#if defined(_WIN32) && !defined(MOJOSHADER_USE_SDL_STDLIB)
     if (len == -1)
     {
         va_copy(ap, va);