Only include <basetsd.h> for VC 6.0 and higher.
diff --git a/PC/config.h b/PC/config.h
index 850af58..f057a75 100644
--- a/PC/config.h
+++ b/PC/config.h
@@ -243,7 +243,9 @@
 
 /* define the ANSI intptr_t type for portable use of a pointer sized
    integer */
+#if _MSC_VER >= 1200 /* This file only exists in VC 6.0 or higher */
 #include <basetsd.h>
+#endif
 #if defined(MS_WINDOWS) && !defined(MS_WIN64)
 typedef long intptr_t;
 #endif