diff --git a/x11-wm/fvwm3/Makefile b/x11-wm/fvwm3/Makefile
index 7c1db0ac05aa..5fd9bf299903 100644
--- a/x11-wm/fvwm3/Makefile
+++ b/x11-wm/fvwm3/Makefile
@@ -1,93 +1,93 @@
 # Created by: Felix Palmen <felix@palmen-it.de>
 
 PORTNAME=	fvwm3
 PORTVERSION=	1.0.2
 CATEGORIES=	x11-wm
 MASTER_SITES=	https://github.com/fvwmorg/fvwm3/releases/download/${PORTVERSION}/ \
 		http://fvwm.sourceforge.net/generated/icon_download/:icons
 
 MAINTAINER=	felix@palmen-it.de
 COMMENT=	F? Virtual Window Manager
 
 LICENSE=	GPLv2
 LICENSE_FILE=	${WRKSRC}/COPYING
 
 LIB_DEPENDS=	libbson-1.0.so:devel/libbson \
 		libevent.so:devel/libevent
 
-USES=		pkgconfig python:3.7+ readline xorg
+USES=		compiler:c11 pkgconfig python:3.7+ readline xorg
 USE_XORG=	ice x11 xext xrandr xrender xt
 
 CONFLICTS_INSTALL=	fvwm-2.*
 
 GNU_CONFIGURE=	yes
 CONFIGURE_ARGS=	ac_cv_path_PYTHON=${PYTHON_CMD} \
 		--disable-golang
 
 OPTIONS_DEFINE=	FRIBIDI ICONS ICONV MANPAGES NLS PERL PNG SVG \
 		XCURSOR XFT XPM XSM
 OPTIONS_DEFAULT=	FRIBIDI ICONV MANPAGES PERL PNG XCURSOR XFT XSM
 OPTIONS_SUB=	yes
 
 FRIBIDI_LIB_DEPENDS=	libfribidi.so:converters/fribidi
 FRIBIDI_CONFIGURE_ENABLE=	bidi
 
 FVWM_ICONS=	fvwm_icons-20070101
 ICONS_DISTFILES=	${DISTNAME}${EXTRACT_SUFX} ${FVWM_ICONS}.tar.bz2:icons
 ICONS_IMPLIES=	XPM
 
 ICONV_USES=	iconv:translit
 ICONV_CONFIGURE_ENABLE=	iconv
 
 MANPAGES_BUILD_DEPENDS=	rubygem-asciidoctor>0:textproc/rubygem-asciidoctor
 MANPAGES_USES=	gmake
 MANPAGES_CONFIGURE_ENABLE=	mandoc
 MANPAGES_IMPLIES=	PERL
 
 NLS_CONFIGURE_ENABLE=	nls
 NLS_USES=	gettext-runtime
 
 PERL_USES=	perl5
 PERL_CONFIGURE_ENABLE=	perllib
 
 PNG_LIB_DEPENDS=	libpng.so:graphics/png
 PNG_CONFIGURE_ENABLE=	png
 
 SVG_LIB_DEPENDS=	librsvg-2.so:graphics/librsvg2-rust
 SVG_USES=	gnome
 SVG_USE=	gnome=cairo,glib20,gdkpixbuf2
 SVG_CONFIGURE_ENABLE=	rsvg
 
 XCURSOR_USE=	xorg=xcursor
 XCURSOR_CONFIGURE_ENABLE=	xcursor
 
 XFT_LIB_DEPENDS=	libfreetype.so:print/freetype2 \
 			libfontconfig.so:x11-fonts/fontconfig
 XFT_USE=	xorg=xft
 XFT_CONFIGURE_ENABLE=	xft
 
 XPM_USE=	xorg=xpm
 XPM_CONFIGURE_OFF=	--with-xpm-library=no
 
 XSM_DESC=	X11 session management support
 XSM_USE=	xorg=sm
 XSM_CONFIGURE_ENABLE=	sm
 
 post-patch:
 	@${REINPLACE_CMD} -e 's,/etc/,${LOCALBASE}/etc/,g' \
 		${WRKSRC}/bin/fvwm-menu-desktop.in
 
 post-install-ICONS-on:
 	${MKDIR} ${STAGEDIR}${PREFIX}/share/fvwm3/pixmaps
 	${INSTALL_DATA} ${WRKDIR}/${FVWM_ICONS}/*.xpm \
 		${STAGEDIR}${PREFIX}/share/fvwm3/pixmaps
 
 post-install-PERL-off:
 .for script in fvwm-convert-2.6 fvwm-menu-directory fvwm-menu-xlock fvwm-perllib
 	${RM} ${STAGEDIR}${PREFIX}/bin/${script}
 .endfor
 .for script in FvwmConsoleC.pl FvwmPerl
 	${RM} ${STAGEDIR}${PREFIX}/libexec/fvwm3/${PORTVERSION}/${script}
 .endfor
 
 .include <bsd.port.mk>