Index: head/math/GiNaC/Makefile
===================================================================
--- head/math/GiNaC/Makefile	(revision 414969)
+++ head/math/GiNaC/Makefile	(revision 414970)
@@ -1,39 +1,40 @@
 # Created by: Ying-Chieh Liao <ijliao@FreeBSD.org>
 # $FreeBSD$
 
 PORTNAME=	GiNaC
 PORTVERSION=	1.7.0
 CATEGORIES=	math
 MASTER_SITES=	ftp://ftpthep.physik.uni-mainz.de/pub/GiNaC/ \
 		http://www.ginac.de/
 DISTNAME=	${PORTNAME:tl}-${PORTVERSION}
 
 MAINTAINER=	stephen@FreeBSD.org
 COMMENT=	C++ library for symbolic mathematical calculations
 
 LICENSE=	GPLv2
 LICENSE_FILE=	${WRKSRC}/COPYING
 
 LIB_DEPENDS=	libcln.so:math/cln
 
 USES=		gmake libtool makeinfo pathfix pkgconfig python:build \
 		tar:bzip2 compiler:c++11-lib
 GNU_CONFIGURE=	yes
 USE_LDCONFIG=	yes
 INSTALL_TARGET=	install-strip
 
 CPPFLAGS+=	-I${LOCALBASE}/include
 LDFLAGS+=	-L${LOCALBASE}/lib
+CXXFLAGS+=	-D_GLIBCXX_USE_C99
 
 INFO=		ginac ginac-examples
 
 .include <bsd.port.pre.mk>
 
 post-patch:
 	@${REINPLACE_CMD} -e 's|-ldl||g' ${WRKSRC}/configure
 .if ${ARCH} != "i386"
 	@${REINPLACE_CMD} -e 's|unsigned|size_t|g' \
 		${WRKSRC}/ginac/parser/parser.cpp
 .endif
 
 .include <bsd.port.post.mk>