diff --git a/pkgs/development/compilers/ghcjs/default.nix b/pkgs/development/compilers/ghcjs/default.nix
index 06588ec949b1..65988901de7a 100644
--- a/pkgs/development/compilers/ghcjs/default.nix
+++ b/pkgs/development/compilers/ghcjs/default.nix
@@ -103,7 +103,7 @@ in mkDerivation (rec {
 
     # Make the patches be relative their corresponding package's directory.
     # See: https://github.com/ghcjs/ghcjs-boot/pull/12
-    for patch in $topDir/ghcjs-boot/patches/*.patch; do
+    for patch in "$topDir/ghcjs-boot/patches/"*.patch; do
       echo "fixing patch: $patch"
       sed -i -e 's@ \(a\|b\)/boot/[^/]\+@ \1@g' $patch
     done