===================================================================
RCS file: /cvs/mandoc/roff.c,v
retrieving revision 1.388
retrieving revision 1.389
diff -u -p -r1.388 -r1.389
--- mandoc/roff.c	2022/05/19 15:37:47	1.388
+++ mandoc/roff.c	2022/05/30 23:03:47	1.389
@@ -1,4 +1,4 @@
-/* $Id: roff.c,v 1.388 2022/05/19 15:37:47 schwarze Exp $ */
+/* $Id: roff.c,v 1.389 2022/05/30 23:03:47 schwarze Exp $ */
 /*
  * Copyright (c) 2010-2015, 2017-2022 Ingo Schwarze <schwarze@openbsd.org>
  * Copyright (c) 2008-2012, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -1529,6 +1529,12 @@ roff_expand(struct roff *r, struct buf *buf, int ln, i
 			ubuf[1] = '\0';
 			res = ubuf;
 			break;
+		case 'V':
+			mandoc_msg(MANDOCERR_UNSUPP, ln, iesc,
+			    "%.*s", iend - iesc, buf->buf + iesc);
+			roff_expand_patch(buf, iendarg, "}", iend);
+			roff_expand_patch(buf, iesc, "${", iarg);
+			continue;
 		case 'n':
 			if (iendarg > iarg)
 				(void)snprintf(ubuf, sizeof(ubuf), "%d",
@@ -1567,9 +1573,8 @@ roff_expand_patch(struct buf *buf, int start, const ch
 {
 	char	*nbuf;
 
-	buf->buf[start] = '\0';
-	buf->sz = mandoc_asprintf(&nbuf, "%s%s%s", buf->buf, repl,
-	    buf->buf + end) + 1;
+	buf->sz = mandoc_asprintf(&nbuf, "%.*s%s%s", start, buf->buf,
+	    repl, buf->buf + end) + 1;
 	free(buf->buf);
 	buf->buf = nbuf;
 }