diff --git a/math/eclib/Makefile b/math/eclib/Makefile
index 2bba0ad45dd2..528c05998935 100644
--- a/math/eclib/Makefile
+++ b/math/eclib/Makefile
@@ -1,30 +1,31 @@
 PORTNAME=	eclib
 PORTVERSION=	20230424
 DISTVERSIONPREFIX=	v
 CATEGORIES=	math
 
 MAINTAINER=	thierry@FreeBSD.org
 COMMENT=	C++ library for arithmetic on elliptic curves
 WWW=		https://homepages.warwick.ac.uk/staff/J.E.Cremona/mwrank/
 
 LICENSE=	GPLv2
 
 LIB_DEPENDS=	libntl.so:math/ntl		\
 		libpari.so:math/pari		\
 		libflint.so:math/flint2		\
 		libboost_thread.so:devel/boost-libs
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	JohnCremona
 
 USES=		autoreconf compiler:c++11-lang libtool localbase
 
 OPTIONS_DEFINE=	DOCS
 
+CXXFLAGS+=	-std=c++11
 LIBS+=		"-lm"
 GNU_CONFIGURE=	yes
 CONFIGURE_ARGS=	--with-flint=${LOCALBASE} --with-boost=${LOCALBASE}
 INSTALL_TARGET=	install-strip
 USE_LDCONFIG=	yes
 
 .include <bsd.port.mk>