Index: head/math/py-z3-solver/Makefile
===================================================================
--- head/math/py-z3-solver/Makefile	(revision 490084)
+++ head/math/py-z3-solver/Makefile	(revision 490085)
@@ -1,25 +1,25 @@
 # $FreeBSD$
 
 PORTNAME=	z3-solver
 DISTVERSIONPREFIX=	z3-
 DISTVERSION=	4.7.1
 CATEGORIES=	math
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Python binding for Z3 Theorem Prover
 
 LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/../../../LICENSE.txt
 
 # CAVEAT: It should have LIB_DEPENDS=libz3.so:math/z3, but currently it rebuilds all code, see https://github.com/Z3Prover/z3/issues/1767
 
-USES=		python
+USES=		compiler:c++11-lang python
 USE_GITHUB=	yes
 GH_ACCOUNT=	Z3Prover
 GH_PROJECT=	z3
 USE_PYTHON=	distutils autoplist
 
 WRKSRC_SUBDIR=	src/api/python
 
 .include <bsd.port.mk>