Subject: bug#9388: 24.0.50; Bug in libxml-parse-xml-region

From: Jason Earl <[email-masked]>
Date: Sat, 27 Aug 2011 18:00:11 -0600

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgement at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from `emacs -Q':

open a file foo.xml with the following contents (although any valid xml
file will do).

--8<---------------cut here---------------start------------->8---
<?xml version='1.0' encoding='utf-8'?>
<foo/>
--8<---------------cut here---------------end--------------->8---

Then start ielm and test libxml-parse-xml-region with the following bit
of elisp.

--8<---------------cut here---------------start------------->8---
(with-current-buffer "foo.xml"
	 (libxml-parse-xml-region (point-min) (point-max)))
--8<---------------cut here---------------end--------------->8---

It will return nil, but it should return "(foo nil)".

This function was broken with bzr commit 105297 to trunk, and I believe
that it can be fixed with the following simple patch (at least it works
for me).

--8<---------------cut here---------------start------------->8---
=== modified file 'src/xml.c'
--- src/xml.c	2011-07-24 14:01:58 +0000
+++ src/xml.c	2011-08-27 22:58:13 +0000
@@ -124,7 +124,7 @@
 
   if (doc != NULL)
     {
-      xmlNode *n = doc->children->next;
+      xmlNode *n = doc->children;
       Lisp_Object r = Qnil;
 
       while (n) {

--8<---------------cut here---------------end--------------->8---

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
/usr/local/share/emacs/24.0.50/etc/DEBUG.

In GNU Emacs 24.0.50.4 (x86_64-unknown-linux-gnu, GTK+ Version 2.24.4)
 of 2011-08-27 on jearl-desktop
Windowing system distributor `The X.Org Foundation', version 11.0.11001000
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: IELM

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-x C-f f o o <tab> . x <tab> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> f o o . x m l <return> 
C-x 2 C-x o M-x i e l m <tab> <return> ( w i t h <tab> 
c u <tab> SPC " f o o . x m l " <return> ( l i b <tab> 
x <tab> SPC ( p o i n t - m i n ) SPC ( p o i n t - 
m a x ) ) <return> ) <return> M-x e m a c s - r e <tab> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> r e p o <tab> r 
<tab> <return>

Recent messages:
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