From: Richard M. Stallman <rms@gnu.org>
Date: Tue, 27 Jan 2004 04:52:09 +0000 (+0000)
Subject: (Freplace_match): Handle nonexistent back-references properly.
X-Git-Tag: ttn-vms-21-2-B4~7818
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=5fbbc83b2b8aa7d2f13c72467b43c6c71d01f388;p=emacs.git

(Freplace_match): Handle nonexistent back-references properly.
---

diff --git a/src/search.c b/src/search.c
index 020573b75a1..c60d68b9374 100644
--- a/src/search.c
+++ b/src/search.c
@@ -2366,13 +2366,21 @@ since only regular expressions have distinguished subexpressions.  */)
 		      substart = search_regs.start[sub];
 		      subend = search_regs.end[sub];
 		    }
-		  else if (c >= '1' && c <= '9' && c <= search_regs.num_regs + '0')
+		  else if (c >= '1' && c <= '9')
 		    {
-		      if (search_regs.start[c - '0'] >= 0)
+		      if (search_regs.start[c - '0'] >= 0
+			  && c <= search_regs.num_regs + '0')
 			{
 			  substart = search_regs.start[c - '0'];
 			  subend = search_regs.end[c - '0'];
 			}
+		      else
+			{
+			  /* If that subexp did not match,
+			     replace \\N with nothing.  */
+			  substart = 0;
+			  subend = 0;
+			}
 		    }
 		  else if (c == '\\')
 		    delbackslash = 1;