Index: head/multimedia/zart/Makefile
===================================================================
--- head/multimedia/zart/Makefile	(revision 514641)
+++ head/multimedia/zart/Makefile	(revision 514642)
@@ -1,39 +1,39 @@
 # $FreeBSD$
 
 PORTNAME=	zart
 PORTVERSION=	g20190911
 CATEGORIES=	multimedia
 MASTER_SITES=	https://gmic.eu/files/source/:gmic
 DISTFILES=	gmic_${GMIC_VERSION}.tar.gz:gmic
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	GMIC GUI for video streams
 
 LICENSE=	CeCILL
 LICENSE_NAME=	CeCILL
 LICENSE_FILE=	${WRKSRC}/LICENSE
 LICENSE_PERMS=	dist-mirror dist-sell pkg-mirror pkg-sell auto-accept
 
 LIB_DEPENDS=	libopencv_core.so:graphics/opencv-core \
 		libopencv_video.so:graphics/opencv \
 		libfftw3.so:math/fftw3
 
-USES=		pkgconfig qmake qt:5
+USES=		compiler:c++11-lang pkgconfig qmake qt:5
 USE_GITHUB=	yes
 GH_ACCOUNT=	c-koi
 GH_TAGNAME=	e1b25e8
 USE_QT=		core gui network widgets xml buildtools_build
 
 GMIC_VERSION=	2.7.4
 
 QMAKE_ARGS=	"GMIC_PATH=${WRKDIR}/gmic-${GMIC_VERSION}/src"
 
 PLIST_FILES=	bin/${PORTNAME}
 
 post-patch:
 	@${REINPLACE_CMD} 's|SYS_gettid|SYS_thr_self|' ${WRKDIR}/gmic-${GMIC_VERSION}/src/gmic.cpp
 
 do-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/${PORTNAME} ${STAGEDIR}${PREFIX}/bin
 
 .include <bsd.port.mk>