diff --git a/x11-toolkits/ztoolkit/Makefile b/x11-toolkits/ztoolkit/Makefile
index 768b0e004ab6..ac55ff3fad26 100644
--- a/x11-toolkits/ztoolkit/Makefile
+++ b/x11-toolkits/ztoolkit/Makefile
@@ -11,7 +11,7 @@ COMMENT=	GUI toolkit heavily inspired by GTK
 LICENSE=	AGPLv3
 LICENSE_FILE=	${WRKSRC}/COPYING
 
-USES=		gnome meson pkgconfig xorg
+USES=		compiler:c11 gnome meson pkgconfig xorg
 USE_GNOME=	cairo
 USE_XORG=	x11