A variant of move-if-change, by Stefan Weil.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3098 c046a42c-6fe2-441c-8c8c-71466251a162

configure

@@ -699,6 +699,8 @@ config_h="config-host.h"
 
 #echo "Creating $config_mak and $config_h"
 
+test -f $config_h && mv $config_h ${config_h}~
+
 echo "# Automatically generated by configure - do not modify" > $config_mak
 echo "# Configured with: $0 $@" >> $config_mak
 echo "/* Automatically generated by configure - do not modify */" > $config_h
@@ -867,6 +869,8 @@ fi
 
 echo "#define CONFIG_UNAME_RELEASE \"$uname_release\"" >> $config_h
 
+test -f ${config_h}~ && cmp -s $config_h ${config_h}~ && mv ${config_h}~ $config_h
+
 for target in $target_list; do
 target_dir="$target"
 config_mak=$target_dir/config.mak
@@ -915,6 +919,8 @@ fi
 
 #echo "Creating $config_mak, $config_h and $target_dir/Makefile"
 
+test -f $config_h && mv $config_h ${config_h}~
+
 mkdir -p $target_dir
 mkdir -p $target_dir/fpu
 if test "$target" = "arm-linux-user" -o "$target" = "armeb-linux-user" ; then
@@ -1074,6 +1080,8 @@ if test "$cocoa" = "yes" ; then
     echo "CONFIG_COCOA=yes" >> $config_mak
 fi
 
+test -f ${config_h}~ && cmp -s $config_h ${config_h}~ && mv ${config_h}~ $config_h
+
 done # for target in $targets
 
 # build tree in object directory if source path is different from current one