bug#17622: 24.4.50; bootstrap failure

[Katsumi Yamaoka <yamaoka@jpl.org>]

A gdb backtrace is attached below.

On Thu, 29 May 2014 08:45:40 +0900, Katsumi Yamaoka wrote:
> Bootstrap fails since yesterday.  I have no clue for this but
> bootstrap-emacs seems to do nothing and to quit silently.

> ,---- (Note: there is no `Wrote *.elc' message.)
>| [...]
>| Dumping under the name emacs
>| Maximum static heap usage: 10470112 of 13631488 bytes
>| 46131 pure bytes used
>| cd ../lisp; make -w compile-first EMACS="../src/bootstrap-emacs.exe"
>| make[3]: Entering directory '/Work/Emacs/lisp'
>| Compiling emacs-lisp/macroexp.el
>| Compiling emacs-lisp/cconv.el
>| Compiling emacs-lisp/byte-opt.el
>| Compiling emacs-lisp/bytecomp.el
>| Compiling emacs-lisp/autoload.el
>| [...]
> `----

$ gdb ./bootstrap-emacs.exe
GNU gdb (GDB) 7.6.50.20130728-cvs (cygwin-special)
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i686-pc-cygwin".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word".
..
Reading symbols from /Work/Emacs/src/bootstrap-emacs.exe...done.
warning: File "/Work/Emacs/src/.gdbinit" auto-loading has been declined by your `auto-load safe-path' set to "$debugdir:$datadir/auto-load".
To enable execution of this file add
	add-auto-load-safe-path /Work/Emacs/src/.gdbinit
line to your configuration file "/home/yamaoka/.gdbinit".
To completely disable this security protection add
	set auto-load safe-path /
line to your configuration file "/home/yamaoka/.gdbinit".
For more information about this security protection see the
"Auto-loading safe path" section in the GDB manual.  E.g., run from the shell:
	info "(gdb)Auto-loading safe path"
^[[?1034h(gdb) r
Starting program: /Work/Emacs/src/bootstrap-emacs.exe 
[New Thread 11900.0x28f8]
[New Thread 11900.0x2d58]

Program received signal SIGSEGV, Segmentation fault.
mmap_alloc (var=var@entry=0x935118 <bss_sbrk_buffer+1188856>, 
    nbytes=nbytes@entry=46) at buffer.c:4895
4895		r->next->prev = r;
(gdb) bt
#0  mmap_alloc (var=var@entry=0x935118 <bss_sbrk_buffer+1188856>, 
    nbytes=nbytes@entry=46) at buffer.c:4895
#1  0x004e23a9 in mmap_realloc (nbytes=46, 
    var=0x935118 <bss_sbrk_buffer+1188856>) at buffer.c:4934
#2  enlarge_buffer_text (b=b@entry=0x935000 <bss_sbrk_buffer+1188576>, 
    delta=delta@entry=0) at buffer.c:5042
#3  0x004e397d in init_buffer () at buffer.c:5290
#4  0x005b2d2f in main (argc=1, argv=0x22ac1c) at emacs.c:1379
(gdb) q
A debugging session is active.

	Inferior 1 [process 11900] will be killed.

Quit anyway? (y or n)