diff --git a/ChangeLog b/ChangeLog
index 38978cf91f..b2025e2b8d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Mon Jan  5 01:47:53 2004  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* lib/mkmf.rb (create_makefile): remove duplicated object files
+	  from $objs on DOSISH platforms.
+
 Sat Jan  3 02:44:48 2004  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* rubysig.h (TRAP_END): preserve errno before switching context.
diff --git a/lib/mkmf.rb b/lib/mkmf.rb
index 27e534bb39..94269cba34 100644
--- a/lib/mkmf.rb
+++ b/lib/mkmf.rb
@@ -784,7 +784,8 @@ def create_makefile(target, srcprefix = nil)
   unless $objs then
     $objs = []
     for f in Dir[File.join(srcdir, "*.{#{SRC_EXT.join(%q{,})}}")]
-      $objs.push(File.basename(f, ".*") << "." << $OBJEXT)
+      obj = File.basename(f, ".*") << "." << $OBJEXT
+      $objs.push(obj) unless $objs.index(obj)
     end
   else
     for i in $objs