lang/sketchy: Fix build with llvm15

- Adopt port

lang/sketchy/Makefile

@@ -4,7 +4,7 @@ PORTREVISION=	1
 CATEGORIES=	lang devel lisp scheme
 MASTER_SITES=	SF/sketchy-lisp/sketchy-lisp/2007-02-18
 
-MAINTAINER=	ports@FreeBSD.org
+MAINTAINER=	bofh@FreeBSD.org
 COMMENT=	Interpreter for purely applicative Scheme
 WWW=		http://sketchy-lisp.sourceforge.net/
 
@@ -13,6 +13,12 @@ USE_LDCONFIG=	yes
 
 OPTIONS_DEFINE=	DOCS
 
+.include <bsd.port.pre.mk>
+
+.if ${OPSYS} == FreeBSD && ( ${OSVERSION} >= 1400079 || ( ${OSVERSION} >= 1302505 && ${OSVERSION} < 1400000 ))
+CFLAGS+=	-Wno-error=int-conversion
+.endif
+
 post-patch:
 	@${REINPLACE_CMD} -e 's|/usr/local|${PREFIX}|g' ${WRKSRC}/sketchy.h
 	@${REINPLACE_CMD} -e 's|/usr/local|${PREFIX}|g' ${WRKSRC}/src/pp.scm
@@ -26,4 +32,4 @@ post-install:
 	${STRIP_CMD} ${STAGEDIR}${PREFIX}/lib/libsketchy.so
 	${LN} -s sketchy.1.gz ${STAGEDIR}${MANPREFIX}/man/man1/sk.1.gz
 
-.include <bsd.port.mk>
+.include <bsd.port.post.mk>