diff --git a/git-filter-branch.sh b/git-filter-branch.sh
index c106f45af73446d26630030f77107efa520aa296..56d1bd0f99743fdb4ba53c457d823b4efc7c1bdd 100755
--- a/git-filter-branch.sh
+++ b/git-filter-branch.sh
@@ -442,19 +442,20 @@ rm -rf "$tempdir"
 
 trap - 0
 
+unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE
+test -z "$ORIG_GIT_DIR" || {
+	GIT_DIR="$ORIG_GIT_DIR" && export GIT_DIR
+}
+test -z "$ORIG_GIT_WORK_TREE" || {
+	GIT_WORK_TREE="$ORIG_GIT_WORK_TREE" &&
+	export GIT_WORK_TREE
+}
+test -z "$ORIG_GIT_INDEX_FILE" || {
+	GIT_INDEX_FILE="$ORIG_GIT_INDEX_FILE" &&
+	export GIT_INDEX_FILE
+}
+
 if [ "$(is_bare_repository)" = false ]; then
-	unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE
-	test -z "$ORIG_GIT_DIR" || {
-		GIT_DIR="$ORIG_GIT_DIR" && export GIT_DIR
-	}
-	test -z "$ORIG_GIT_WORK_TREE" || {
-		GIT_WORK_TREE="$ORIG_GIT_WORK_TREE" &&
-		export GIT_WORK_TREE
-	}
-	test -z "$ORIG_GIT_INDEX_FILE" || {
-		GIT_INDEX_FILE="$ORIG_GIT_INDEX_FILE" &&
-		export GIT_INDEX_FILE
-	}
 	git read-tree -u -m HEAD
 fi
 
diff --git a/t/t7003-filter-branch.sh b/t/t7003-filter-branch.sh
index b0a9d7d536314ec842b141c09ba0d6f8b06b6288..6a9936e5c45a973f2fd64a2fe20463497f9564eb 100755
--- a/t/t7003-filter-branch.sh
+++ b/t/t7003-filter-branch.sh
@@ -39,7 +39,9 @@ test_expect_success 'result is really identical' '
 '
 
 test_expect_success 'rewrite bare repository identically' '
-	(git config core.bare true && cd .git && git filter-branch branch)
+	(git config core.bare true && cd .git &&
+	 git filter-branch branch > filter-output 2>&1 &&
+	! fgrep fatal filter-output)
 '
 git config core.bare false
 test_expect_success 'result is really identical' '