diff --git a/pkgs/build-support/setup-hooks/audit-tmpdir.sh b/pkgs/build-support/setup-hooks/audit-tmpdir.sh
index ffaa61f2d80..0f515842ebc 100644
--- a/pkgs/build-support/setup-hooks/audit-tmpdir.sh
+++ b/pkgs/build-support/setup-hooks/audit-tmpdir.sh
@@ -27,7 +27,7 @@ auditTmpdir() {
         fi
 
         if  isScript "$i"; then
-            if [ -e "$(dirname $i)/.$(basename $i)-wrapped" ]; then
+            if [ -e "$(dirname "$i")/.$(basename "$i")-wrapped" ]; then
                 if grep -q -F "$TMPDIR" "$i"; then
                     echo "wrapper script $i contains a forbidden reference to $TMPDIR"
                     exit 1