Index: head/devel/libconcurrent/Makefile
===================================================================
--- head/devel/libconcurrent/Makefile	(revision 410472)
+++ head/devel/libconcurrent/Makefile	(revision 410473)
@@ -1,49 +1,55 @@
 # Created by: Tobias Kortkamp <t@tobik.me>
 # $FreeBSD$
 
 PORTNAME=	libconcurrent
 PORTVERSION=	0.0.20160303
+PORTREVISION=	1
 CATEGORIES=	devel
 
 MAINTAINER=	t@tobik.me
 COMMENT=	Tiny asymmetric-coroutine library
 
 LICENSE=	ZLIB
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 BUILD_DEPENDS=	nasm:${PORTSDIR}/devel/nasm
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	sharow
 # Rolling release
 GH_TAGNAME=	f55d33a789a4b2c6267268ec2d44a245f766f500
 
 ONLY_FOR_ARCHS=	i386 amd64
 
 OPTIONS_DEFINE=	EXAMPLES
 OPTIONS_DEFAULT=	EXAMPLES
 
 MAKEFILE=	makefile
 MAKE_ARGS=	LIBCONCURRENT_DESTDIR=${STAGEDIR}${PREFIX}
-USES=		gmake
+USES=		gmake compiler:c11
 
 post-patch:
+# Remove explicitly (re-)set C compiler and linker in libconcurrent's
+# makefile.  The ports system will provide the correct ones.  This is
+# needed on FreeBSD 9 where cc does not understand -std=c11.
+	@${REINPLACE_CMD} 's/CC=cc//g' ${WRKSRC}/makefile
+	@${REINPLACE_CMD} 's/LD=ld//g' ${WRKSRC}/makefile
 # libconcurrent's makefile resets ${ARCH} internally and the ports
 # system interferes with that for some reason, so replace it with a
 # more neutral variant.
 	@${REINPLACE_CMD} 's/ARCH/LIBCONCURRENT_ARCH/g' ${WRKSRC}/makefile
 # Same with ${DESTDIR}
 	@${REINPLACE_CMD} 's/DESTDIR/LIBCONCURRENT_DESTDIR/g' ${WRKSRC}/makefile
 
 post-patch-EXAMPLES-on:
 # Fix examples makefile to work out-of-tree
 	@${REINPLACE_CMD} 's|INCDIR+=-I../include|INCDIR+=-I${PREFIX}/include|g' \
 		${WRKSRC}/examples/makefile
 	@${REINPLACE_CMD} 's|-L../|-L${PREFIX}/lib|g' \
 		${WRKSRC}/examples/makefile
 
 post-install-EXAMPLES-on:
 	@${MKDIR} ${STAGEDIR}${EXAMPLESDIR}
 	@(cd ${WRKSRC}/examples && ${COPYTREE_SHARE} . ${STAGEDIR}${EXAMPLESDIR})
 
 .include <bsd.port.mk>