diff --git a/gettext.pri b/gettext.pri
index 84fffa55..26a562a4 100644
--- a/gettext.pri
+++ b/gettext.pri
@@ -19,8 +19,9 @@ macx: {
       GETTEXT_LIBPATH = $$OPENSCAD_LIBRARIES_DIR/lib
     }
   }
-  GETTEXT_CXXFLAGS=-I$$GETTEXT_INCLUDEPATH
-  GETTEXT_LIBS=-L$$GETTEXT_LIBPATH -lintl -liconv
+  !isEmpty(GETTEXT_INCLUDEPATH): GETTEXT_CXXFLAGS = -I$$GETTEXT_INCLUDEPATH
+  !isEmpty(GETTEXT_LIBPATH): GETTEXT_LIBS = -L$$GETTEXT_LIBPATH 
+  GETTEXT_LIBS += -lintl -liconv
 }
 
 QMAKE_CXXFLAGS += $$GETTEXT_CXXFLAGS