Revert unconditional config.h overwriting, it may cause unnecessary rebuilds.

Originally committed as revision 5020 to svn://svn.ffmpeg.org/ffmpeg/trunk

diff --git a/configure b/configure
index 9b5e942ce9831ef11f63744a4e86ef1999447478..1770aa4ead8ecec8cf32e3fb5ca8c6d5899c065f 100755 (executable)
--- a/configure
+++ b/configure
@@ -1939,7 +1939,13 @@ for codec in $CODEC_LIST ; do
     echo "CONFIG_`echo $codec | tr a-z A-Z`=yes" >> config.mak
 done
 
-mv -f $TMPH config.h
+# Do not overwrite config.h if unchanged to avoid superfluous rebuilds.
+diff $TMPH config.h >/dev/null 2>&1
+if test $? -ne 0 ; then
+        mv -f $TMPH config.h
+else
+        echo "config.h is unchanged"
+fi
 
 rm -f $TMPO $TMPC $TMPE $TMPS $TMPH