diff --git a/tests/functional/gc-runtime.sh b/tests/functional/gc-runtime.sh
index 2ee72b61e..b5f6f769c 100755
--- a/tests/functional/gc-runtime.sh
+++ b/tests/functional/gc-runtime.sh
@@ -12,27 +12,27 @@ esac
 set -m # enable job control, needed for kill
 
 profiles="$NIX_STATE_DIR"/profiles
-rm -rf $profiles
+rm -rf "$profiles"
 
-nix-env -p $profiles/test -f ./gc-runtime.nix -i gc-runtime
+nix-env -p "$profiles/test" -f ./gc-runtime.nix -i gc-runtime
 
-outPath=$(nix-env -p $profiles/test -q --no-name --out-path gc-runtime)
-echo $outPath
+outPath=$(nix-env -p "$profiles/test" -q --no-name --out-path gc-runtime)
+echo "$outPath"
 
 echo "backgrounding program..."
-$profiles/test/program &
+"$profiles"/test/program &
 sleep 2 # hack - wait for the program to get started
 child=$!
 echo PID=$child
 
-nix-env -p $profiles/test -e gc-runtime
-nix-env -p $profiles/test --delete-generations old
+nix-env -p "$profiles/test" -e gc-runtime
+nix-env -p "$profiles/test" --delete-generations old
 
 nix-store --gc
 
 kill -- -$child
 
-if ! test -e $outPath; then
+if ! test -e "$outPath"; then
     echo "running program was garbage collected!"
     exit 1
 fi