diff --git a/math/flopc++/Makefile b/math/flopc++/Makefile
index bff88d1552c9..ec31e8986f28 100644
--- a/math/flopc++/Makefile
+++ b/math/flopc++/Makefile
@@ -1,30 +1,30 @@
 PORTNAME=	flopc++
-DISTVERSION=	1.2.5
-PORTREVISION=	1
+DISTVERSION=	1.2.5.20200527
 CATEGORIES=	math
-MASTER_SITES=	http://www.coin-or.org/download/pkgsource/FlopC++/
 PKGNAMEPREFIX=	coin-or-
-DISTNAME=	FlopC++-${DISTVERSION}
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Library for solving Linear Optimization Problems in C++
 
 LICENSE=	EPL
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 LIB_DEPENDS=	libCoinUtils.so:math/coinutils \
 		libOsi.so:math/osi
 
 USES=		gmake libtool pkgconfig tar:tgz
 USE_LDCONFIG=	yes
 
-USE_GCC=	yes # clang breaks: no matching conversion for functional-style cast from 'const flopc::SUBSETREF' to 'flopc::MP_domain' https://github.com/coin-or/FlopCpp/issues/28
+USE_GITHUB=	yes
+GH_ACCOUNT=	coin-or
+GH_PROJECT=	FlopCpp
+GH_TAGNAME=	d4c1d98 # fix-clang branch
 
 GNU_CONFIGURE=	yes
 
 INSTALL_TARGET=	install-strip
 
 post-install:
 	@${RM} -r ${STAGEDIR}${PREFIX}/share
 
 .include <bsd.port.mk>
diff --git a/math/flopc++/distinfo b/math/flopc++/distinfo
index 04ca64acec35..f55a0d2210e2 100644
--- a/math/flopc++/distinfo
+++ b/math/flopc++/distinfo
@@ -1,3 +1,3 @@
-TIMESTAMP = 1619779256
-SHA256 (FlopC++-1.2.5.tgz) = 8b4a21d26bcd375995a8f6e1de25674afee6f5d49cf21c682ab3c543c64c25a7
-SIZE (FlopC++-1.2.5.tgz) = 357541
+TIMESTAMP = 1620783296
+SHA256 (coin-or-FlopCpp-1.2.5.20200527-d4c1d98_GH0.tar.gz) = c33d1821167a99f3b19075cc3cf72d6510f68e137e12e48000c39ea4ed3b3f02
+SIZE (coin-or-FlopCpp-1.2.5.20200527-d4c1d98_GH0.tar.gz) = 619152