diff -ru pari-2.1.7.orig\src\gp\highlvl.c pari-2.1.7\src\gp\highlvl.c
--- pari-2.1.7.orig\src\gp\highlvl.c Tue Apr 23 17:29:37 2002
+++ pari-2.1.7\src\gp\highlvl.c Wed Mar 03 09:21:11 2010
@@ -18,6 +18,13 @@
 /*        SOME GP FUNCTION THAT MAY BE USEFUL OUTSIDE OF IT        */
 /*                                                                 */
 /*******************************************************************/
+
+/* we need to include windows.h quite early to avoid some macro name collisions */
+#ifdef _WIN32
+#  define WIN32_LEAN_AND_MEAN
+#  include <windows.h>
+#endif
+
 #include "pari.h"
 #ifdef macintosh
 #  include "rect.h"