diff --git a/ChangeLog b/ChangeLog
index 8a9b4928cb..cdb54d27da 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Dec 24 00:23:13 2014  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* tool/extlibs.rb (do_extract): the pipe should be binmode.
+
 Wed Dec 24 00:21:44 2014  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* Makefile.in, common.mk: move common-srcs to Makefile.in because
diff --git a/tool/extlibs.rb b/tool/extlibs.rb
index aab08d0372..a8554b3de2 100755
--- a/tool/extlibs.rb
+++ b/tool/extlibs.rb
@@ -52,7 +52,7 @@ def do_extract(cache, dir)
   else
     inp = cache
   end
-  inp ||= f
+  inp ||= f.binmode
   ext = File.extname(cache)
   case ext
   when '.tar', /\A\.t[gbx]z\z/