diff --git a/ChangeLog b/ChangeLog
index 3a4bc8443f..9d771898c4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu May  3 02:07:45 2001  Usaku Nakamura  <usa@osb.att.ne.jp>
+
+	* win32/config.h.in: add SIZEOF___INT64 definition.
+
 Wed May  2 20:39:35 2001  WATANABE Hirofumi  <eban@ruby-lang.org>
 
 	* dir.c (rb_glob, rb_globi): remove unnecessary FNM_PATHNAME.
diff --git a/win32/config.h.in b/win32/config.h.in
index 0f017e9ac2..22073b0d14 100644
--- a/win32/config.h.in
+++ b/win32/config.h.in
@@ -57,6 +57,7 @@
 #define SIZEOF_INT   4
 #define SIZEOF_SHORT 2
 #define SIZEOF_LONG  4
+#define SIZEOF___INT64 8
 #define SIZEOF_VOIDP 4
 #define SIZEOF_FLOAT 4
 #define SIZEOF_DOUBLE 8