diff --git a/include/wx/defs.h b/include/wx/defs.h
index ff94eca938..49e76fe214 100644
--- a/include/wx/defs.h
+++ b/include/wx/defs.h
@@ -146,7 +146,7 @@
 // "old" GNUWIN32 is the one without Norlander's headers: it lacks the standard
 // Win32 headers and we define the used stuff ourselves for it in
 // wx/msw/gnuwin32/extra.h
-#if defined(__GNUWIN32__) && !wxUSE_NORLANDER_HEADERS
+#if defined(__GNUC__) && !wxUSE_NORLANDER_HEADERS
     #define __GNUWIN32_OLD__
 #endif