===================================================================
RCS file: /cvs/mandoc/roff.c,v
retrieving revision 1.380
retrieving revision 1.383
diff -u -p -r1.380 -r1.383
--- mandoc/roff.c	2021/10/04 14:19:14	1.380
+++ mandoc/roff.c	2022/04/24 17:40:22	1.383
@@ -1,6 +1,6 @@
-/* $Id: roff.c,v 1.380 2021/10/04 14:19:14 schwarze Exp $ */
+/* $Id: roff.c,v 1.383 2022/04/24 17:40:22 schwarze Exp $ */
 /*
- * Copyright (c) 2010-2015, 2017-2021 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2010-2015, 2017-2022 Ingo Schwarze <schwarze@openbsd.org>
  * Copyright (c) 2008-2012, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  *
  * Permission to use, copy, modify, and distribute this software for any
@@ -1401,7 +1401,7 @@ roff_expand(struct roff *r, struct buf *buf, int ln, i
 
 		term = '\0';
 		cp = stesc + 1;
-		if (*cp == 'E')
+		while (*cp == 'E')
 			cp++;
 		esct = cp;
 		switch (*esct) {
@@ -2433,9 +2433,11 @@ roff_cond_sub(ROFF_ARGS)
 			}
 		}
 	} else if (t != TOKEN_NONE &&
-	    (rr || roffs[t].flags & ROFFMAC_STRUCT))
+	    (rr || roffs[t].flags & ROFFMAC_STRUCT)) {
 		irc |= (*roffs[t].proc)(r, t, buf, ln, ppos, pos, offs);
-	else
+		if (irc & ROFF_WHILE)
+			irc &= ~(ROFF_LOOPCONT | ROFF_LOOPEXIT);
+	} else
 		irc |= rr ? ROFF_CONT : ROFF_IGN;
 	return irc;
 }
@@ -3870,8 +3872,9 @@ static int
 roff_shift(ROFF_ARGS)
 {
 	struct mctx	*ctx;
-	int		 levels, i;
+	int		 argpos, levels, i;
 
+	argpos = pos;
 	levels = 1;
 	if (buf->buf[pos] != '\0' &&
 	    roff_evalnum(r, ln, buf->buf, &pos, &levels, 0) == 0) {
@@ -3886,8 +3889,12 @@ roff_shift(ROFF_ARGS)
 	ctx = r->mstack + r->mstackpos;
 	if (levels > ctx->argc) {
 		mandoc_msg(MANDOCERR_SHIFT,
-		    ln, pos, "%d, but max is %d", levels, ctx->argc);
+		    ln, argpos, "%d, but max is %d", levels, ctx->argc);
 		levels = ctx->argc;
+	}
+	if (levels < 0) {
+		mandoc_msg(MANDOCERR_ARG_NEG, ln, argpos, "shift %d", levels);
+		levels = 0;
 	}
 	if (levels == 0)
 		return ROFF_IGN;