Index: head/archivers/ppmd/Makefile
===================================================================
--- head/archivers/ppmd/Makefile	(revision 462481)
+++ head/archivers/ppmd/Makefile	(revision 462482)
@@ -1,23 +1,30 @@
 # Created by: Emanuel Haupt <ehaupt@critical.ch>
 # $FreeBSD$
 
 PORTNAME=	ppmd
 PORTVERSION=	20050811
 CATEGORIES=	archivers
 MASTER_SITES=	LOCAL/ehaupt
 
 MAINTAINER=	ehaupt@FreeBSD.org
 COMMENT=	Fast archiver with good compression ratio
 
 PORTDOCS=	read_me.txt
 PLIST_FILES=	bin/ppmd man/man1/ppmd.1.gz
 
 OPTIONS_DEFINE=	DOCS
 
+.include <bsd.port.pre.mk>
+
+# does not compile with clang 6.0.0
+.if ${OPSYS} == FreeBSD && ${OSVERSION} >= 1200056
+USE_GCC=	yes
+.endif
+
 do-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/${PORTNAME} ${STAGEDIR}${PREFIX}/bin
 	${INSTALL_MAN} ${WRKSRC}/${PORTNAME}.1 ${STAGEDIR}${MANPREFIX}/man/man1
 	@${MKDIR} ${STAGEDIR}${DOCSDIR}
 	${INSTALL_DATA} ${WRKSRC}/${PORTDOCS} ${STAGEDIR}${DOCSDIR}
 
-.include <bsd.port.mk>
+.include <bsd.port.post.mk>