diff --git a/devel/pructl/Makefile b/devel/pructl/Makefile
index c23c86038a48..6c370e7b69ae 100644
--- a/devel/pructl/Makefile
+++ b/devel/pructl/Makefile
@@ -1,23 +1,25 @@
 PORTNAME=	pructl
 DISTVERSION=	0.2
 PORTREVISION=	1
 CATEGORIES=	devel
 
 MAINTAINER=	jmg@FreeBSD.org
 # The maintainer says, if you're actively using this you are free to
 # take this port.
 COMMENT=	Utilities to interface with PRUs
 WWW=		https://bitbucket.org/rpaulo/pructl
 
 LICENSE=	BSD2CLAUSE
 
+BROKEN=		does not build: /lib/libc.so.7: undefined reference to _Block_copy
+
 USE_GITHUB=	yes
 GH_ACCOUNT=	rpaulo
 GH_TAGNAME=	v0.2
 
 LIB_DEPENDS=	libpru.so:devel/libpru
 
 USES=		cmake libedit
 USE_CSTD=	c99
 
 .include <bsd.port.mk>