bug#17622: 24.4.50; bootstrap failure

[Katsumi Yamaoka]

I verified simply reverting r117168 builds Emacs successfully on
Cygwin.

On Thu, 29 May 2014 11:02:32 +0900, Katsumi Yamaoka wrote:
> 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>
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> ..
> 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)