Index: head/deskutils/ausweisapp2/Makefile
===================================================================
--- head/deskutils/ausweisapp2/Makefile	(revision 528332)
+++ head/deskutils/ausweisapp2/Makefile	(revision 528333)
@@ -1,31 +1,31 @@
 # $FreeBSD$
 
 PORTNAME=	ausweisapp2
 DISTVERSION=	1.20.0
 PORTREVISION=	1
 CATEGORIES=	deskutils security
 
 MAINTAINER=	freebsd@sysctl.cz
 COMMENT=	Official authentication app for German ID cards and residence permits
 
 LICENSE=	EUPLv1.2
 LICENSE_NAME=	European Union Public Licence V. 1.2
 LICENSE_FILE=	${WRKSRC}/LICENSE.txt
 LICENSE_PERMS=	dist-mirror dist-sell pkg-mirror pkg-sell auto-accept
 
 BUILD_DEPENDS=	pcsc-lite>0:devel/pcsc-lite
 LIB_DEPENDS=	libhttp_parser.so:www/http-parser \
 		libpcsclite.so:devel/pcsc-lite
 
-USES=		cmake pkgconfig qmake qt:5 ssl
+USES=		cmake compiler:c++17-lang pkgconfig qmake qt:5 ssl
 USE_GITHUB=	yes
 GH_ACCOUNT=	Governikus
 GH_PROJECT=	AusweisApp2
 USE_QT=		buildtools concurrent core declarative gui linguisttools \
 		network quickcontrols2 svg websockets widgets
 
 # The VENDOR variable controls the name of the directory in ${PREFIX}/share.
 CMAKE_ARGS=	-DVENDOR=${PORTNAME}
 MAKE_ENV=	DESTDIR=${STAGEDIR}
 
 .include <bsd.port.mk>