diff --git a/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh b/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh
index b785a779c8bc..7f6ddb76ad57 100644
--- a/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh
+++ b/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh
@@ -1,6 +1,6 @@
 . @fix_qmake_libtool@
 
-qmakeFlags=( $qmakeFlags )
+qmakeFlags=( ${qmakeFlags-} )
 
 qmakePrePhase() {
     qmakeFlags=( \