diff --git a/ChangeLog b/ChangeLog
index 47f8156f92..c2822bfae7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Aug 14 21:14:07 2001  Akinori MUSHA  <knu@iDaemons.org>
+
+	* ext/digest/sha2/extconf.rb: do not create Makefile when no 64bit
+	  integer type is detected.
+
 Tue Aug 14 17:09:12 2001  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* range.c (range_step): new method.
diff --git a/ext/digest/sha2/extconf.rb b/ext/digest/sha2/extconf.rb
index fcbc1ddd8b..144f266b20 100644
--- a/ext/digest/sha2/extconf.rb
+++ b/ext/digest/sha2/extconf.rb
@@ -17,4 +17,12 @@ have_header("inttypes.h")
 
 have_header("unistd.h")
 
+unless try_link(<<SRC, $defs.join(' '))
+#include "../defs.h"
+main(){}
+SRC
+  puts "** Cannot find a 64bit integer type - skipping the SHA2 module."
+  exit 1
+end
+
 create_makefile("digest/sha2")