diff --git a/buildcore.sh b/buildcore.sh
index a0ae1169a..b6535127e 100755
--- a/buildcore.sh
+++ b/buildcore.sh
@@ -189,6 +189,22 @@ fi
 SOMETHINGCHANGED=0
 if [ "$GIT" = "1" ]; then
 	# using git
+
+	# Do some error checking for the build before starting...
+	# check if there's any modifications to git current repo
+	MODIFIED_FILES=`git ls-files --modified | tr '\n' ', '`
+	if [ $MODIFIED_FILES ]; then
+		echo "The following files have been modified in the local repository: $MODIFIED_FILES..."
+		echo "Not a clean build, aborting..."
+		exit 3
+	fi
+	# check if there's any modifications to git current repo
+	UNTRACKED_FILES=`git ls-files --others | tr '\n' ', '`
+	if [ -n $UNTRACKED_FILES ]; then
+		echo "The following files are not tracked in git: $UNTRACKED_FILES..."
+		echo "Not a clean build, aborting..."
+		exit 3
+	fi
 	if [ -z "$GITUP" ]; then
 		GITUP=../coregitup
 		echo "git pull > $GITUP"
diff --git a/makerpm b/makerpm
index fba98fc4c..14a4d7c02 100755
--- a/makerpm
+++ b/makerpm
@@ -45,6 +45,11 @@ function makenoarch {
 		rm -f $RPMROOT/SRPMS/$RPMNAME-$VER*rpm $RPMROOT/RPMS/noarch/$RPMNAME-$VER*rpm
 		rpmbuild $QUIET -ta $RPMROOT/SOURCES/$RPMNAME-$VER.tar.gz
 		RC=$?
+
+		if [ $RPMNAME = "xCAT-UI" ]; then
+			# undo the modifications above to leave the sandbox prestine on the build machine
+			git checkout xCAT-UI/xCAT-UI.spec
+		fi
 	fi
 }