Index: generic/nsfInt.h
===================================================================
diff -u -r880487204ff2da18d2d25ebd727b9b4bbda86c8e -r836e08bf2af69a30dcd2cf6bb2e19f97d798b98a
--- generic/nsfInt.h	(.../nsfInt.h)	(revision 880487204ff2da18d2d25ebd727b9b4bbda86c8e)
+++ generic/nsfInt.h	(.../nsfInt.h)	(revision 836e08bf2af69a30dcd2cf6bb2e19f97d798b98a)
@@ -35,6 +35,21 @@
 # define HAVE_UINTPTR_T 
 #endif
 
+/*
+ * MinGW and MinGW-w64 provide both MSCRT-compliant and ANSI-compliant
+ * implementations of certain I/O operations (e.g., *printf()). By
+ * setting __USE_MINGW_ANSI_STDIO to 1 explicitly, we can assume the
+ * ANSI versions.
+ *
+ * Note: It is sufficient to test for __MINGW32__ to trap all MinGW
+ * tool chains, including 64bit versions. See
+ * http://sourceforge.net/p/predef/wiki/Compilers/#mingw-and-mingw-w64
+ */
+
+#if defined(__MINGW32__) && !defined(__USE_MINGW_ANSI_STDIO)
+#define __USE_MINGW_ANSI_STDIO 1
+#endif
+
 #include <tclInt.h>
 #include "nsf.h"
 
@@ -1057,7 +1072,6 @@
 #endif
 #endif
 
-
 #if !defined(NDEBUG)
 /*# define NSF_INLINE*/
 #endif