--- devel/abseil/Makefile	(revision 557453)
+++ devel/abseil/Makefile	(working copy)
@@ -3,6 +3,7 @@ 
 
 PORTNAME=	abseil
 PORTVERSION=	20200923.2
+PORTREVISION=	1
 CATEGORIES=	devel
 
 MAINTAINER=	danfe@FreeBSD.org
@@ -14,6 +15,8 @@ 
 USE_GITHUB=	yes
 GH_PROJECT=	${PORTNAME}-cpp
 
-CMAKE_ARGS=	-DBUILD_SHARED_LIBS:BOOL=ON
+CMAKE_ARGS=	-DBUILD_SHARED_LIBS:BOOL=ON \
+		-DCMAKE_CXX_STANDARD=17
+# see https://github.com/abseil/abseil-cpp/issues/819
 
 .include <bsd.port.mk>