Index: head/devel/py-grpcio-tools/Makefile
===================================================================
--- head/devel/py-grpcio-tools/Makefile	(revision 500566)
+++ head/devel/py-grpcio-tools/Makefile	(revision 500567)
@@ -1,26 +1,26 @@
 # Created by: vanilla@
 # $FreeBSD$
 
 PORTNAME=	grpcio-tools
 PORTVERSION=	1.20.1
 CATEGORIES=	devel python
 MASTER_SITES=	CHEESESHOP
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}
 
 MAINTAINER=	vanilla@FreeBSD.org
 COMMENT=	Protobuf code generator for gRPC
 
 LICENSE=	BSD3CLAUSE
 
 RUN_DEPENDS=	${PYTHON_PKGNAMEPREFIX}grpcio>1:devel/py-grpcio@${PY_FLAVOR}
 LIB_DEPENDS=	libcares.so:dns/c-ares
 
-USES=		localbase:ldflags python
+USES=		compiler:c++11-lang localbase:ldflags python
 USE_PYTHON=	autoplist distutils
 CFLAGS+=	-DHAVE_PTHREAD=1
 LDFLAGS+=	-lcares
 
 post-install:
 	${STRIP_CMD} ${STAGEDIR}${PYTHONPREFIX_SITELIBDIR}/grpc_tools/_protoc_compiler.so
 
 .include <bsd.port.mk>