updated for version 7.3.1313
Problem:    :py and :py3 don't work when compiled with Cygwin or MingW with 64
            bit.
Solution:   Add -DMS_WIN64 to the build command. (Ken Takata)
diff --git a/src/Make_ming.mak b/src/Make_ming.mak
index 45d903f..7aa3994 100644
--- a/src/Make_ming.mak
+++ b/src/Make_ming.mak
@@ -328,6 +328,9 @@
 DEF_GUI=-DFEAT_GUI_W32 -DFEAT_CLIPBOARD
 DEFINES=-DWIN32 -DWINVER=$(WINVER) -D_WIN32_WINNT=$(WINVER) \
 	-DHAVE_PATHDEF -DFEAT_$(FEATURES)
+ifeq ($(ARCH),x86-64)
+DEFINES+=-DMS_WIN64
+endif
 ifeq ($(CROSS),yes)
 # cross-compiler prefix:
 CROSS_COMPILE = i586-pc-mingw32msvc-