Index: head/devel/py-sysctl/Makefile
===================================================================
--- head/devel/py-sysctl/Makefile	(revision 552141)
+++ head/devel/py-sysctl/Makefile	(revision 552142)
@@ -1,22 +1,23 @@
 # Created by: William Grzybowski <wg@FreeBSD.org>
 # $FreeBSD$
 
 PORTNAME=	sysctl
 PORTVERSION=	0.3.20201005
 CATEGORIES=	devel python
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}
 
 MAINTAINER=	wg@FreeBSD.org
 COMMENT=	Wrapper for the sysctl system functions
 
 LICENSE=	BSD2CLAUSE
 
 USES=		python
+USE_CSTD=	c99
 USE_PYTHON=	distutils autoplist
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	william-gr
 GH_PROJECT=	py-sysctl
 GH_TAGNAME=	eeb46ce2
 
 .include <bsd.port.mk>