Index: head/textproc/htmldoc/Makefile
===================================================================
--- head/textproc/htmldoc/Makefile	(revision 487855)
+++ head/textproc/htmldoc/Makefile	(revision 487856)
@@ -1,49 +1,50 @@
 # Created by: Glenn Trewitt <glenn@trewitt.org>
 # $FreeBSD$
 
 PORTNAME=		htmldoc
 PORTVERSION=		1.9.3
 DISTVERSIONPREFIX=	v
 CATEGORIES=		textproc
 
 MAINTAINER=	jose@diasfernandes.pt
 COMMENT=	Converts HTML to PDF and/or PostScript
 
 LICENSE=	GPLv2
 LICENSE_FILE=	${WRKSRC}/COPYING
 
 BROKEN_mips=	Complains of expecting ) before png_ptr
 
 LIB_DEPENDS=	libpng.so:graphics/png
 
+USES=		compiler:c11
 USE_GITHUB=	yes
 GH_ACCOUNT=	michaelrsweet
 
 HAS_CONFIGURE=	yes
 MAKE_ARGS=	mandir="${MANDIRS}"
 
 OPTIONS_DEFINE=		HTMLDOCGUI GNUTLS
 OPTIONS_DEFAULT=	GNUTLS
 
 HTMLDOCGUI_DESC=	Build GUI front-end
 HTMLDOCGUI_CONFIGURE_WITH=	gui=yes
 HTMLDOCGUI_LIB_DEPENDS=		libfltk.so:x11-toolkits/fltk \
 				libfontconfig.so:x11-fonts/fontconfig
 HTMLDOCGUI_USE=			XORG=x11,xrender,xcursor,xfixes \
 				xext,xft,xinerama jpeg
 GNUTLS_CONFIGURE_ENABLE=	gnutls
 GNUTLS_USES=			pkgconfig
 GNUTLS_LIB_DEPENDS=		libgnutls.so:security/gnutls
 
 .include <bsd.port.pre.mk>
 
 # Fix arm64 build
 .if ${ARCH} == "aarch64"
 pre-build:
 	${REINPLACE_CMD} -e '/PNG_FILTER_OPTIMIZATIONS(pp, bpp);/d' ${WRKSRC}/png/pngrutil.c
 .endif
 
 post-install:
 	${STRIP_CMD} ${STAGEDIR}${PREFIX}/bin/htmldoc
 
 .include <bsd.port.post.mk>