Index: Makefile
===================================================================
--- Makefile	(revision 480965)
+++ Makefile	(working copy)
@@ -22,7 +22,7 @@
 		libxkbcommon.so:x11/libxkbcommon
 RUN_DEPENDS=	xdg-open:devel/xdg-utils
 
-USES=		jpeg localbase qmake:no_env qt-dist:5,base
+USES=		compiler:c++17-lang jpeg localbase qmake:no_env qt-dist:5,base
 USE_GL=		gl egl
 USE_GNOME=	glib20
 USE_QT=		core dbus network qmake_build buildtools_build