diff --git a/ChangeLog b/ChangeLog
index 3e2f71d114..1b027edd66 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,7 +1,9 @@
 Sun Jul 27 21:16:30 2003  WATANABE Hirofumi  <eban@ruby-lang.org>
 
 	* ext/openssl/extconf.rb: better support MinGW.  add
-	dir_config("kerberos") and with_config("pkg-config").
+	  dir_config("kerberos") and with_config("pkg-config").
+
+	* mkconfig.rb: initialize global variables to avoid warnings.
 
 Sun Jul 27 14:43:37 2003  NAKAMURA, Hiroshi  <nahi@ruby-lang.org>
 
diff --git a/mkconfig.rb b/mkconfig.rb
index 9eea3198a1..b697dfb9d1 100644
--- a/mkconfig.rb
+++ b/mkconfig.rb
@@ -1,5 +1,10 @@
 #!./miniruby -s
 
+# avoid warnings with -d.
+$srcdir ||= nil
+$install_name ||= nil
+$so_name ||= nil
+
 require File.dirname($0)+"/lib/ftools"
 mkconfig = File.basename($0)