* configure.in: keep old config.h unless changed.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@2050 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,7 @@
+Wed Feb  6 17:18:54 2002  Nobuyoshi Nakada  <nobu.nakada@nifty.ne.jp>
+
+	* configure.in: keep old config.h unless changed.
+
 Wed Feb  6 13:28:53 2002  Amos Gouaux  <amos+ruby@utdallas.edu>
 
 	* lib/net/imap.rb: OpenSSL support.

configure.in

@@ -1093,8 +1093,12 @@ if test "$search_path" != ""; then
     AC_DEFINE_UNQUOTED(RUBY_SEARCH_PATH,"$search_path")
 fi
 
-echo "creating config.h"
-tr -d '\015' < confdefs.h > config.h
+if test -f config.h && tr -d '\015' < confdefs.h | cmp -s config.h -; then
+  echo "config.h unchanged"
+else
+  echo "creating config.h"
+  tr -d '\015' < confdefs.h > config.h
+fi
 : > confdefs.h
 
 AC_OUTPUT($FIRSTMAKEFILE Makefile ext/extmk.rb)