cvs commit: src/lib/libc/stdlib malloc.c

[Giorgos Keramidas]

On 2006-01-13 11:07, Jason Evans <jasone at FreeBSD.org> wrote:
>On Jan 12, 2006, at 5:29 PM, Giorgos Keramidas wrote:
>>
>> [...]
>>
>> Does this look like an off-by-one error to you too Jason?
>> Apparently, the allocated size of s->data is s->size, which is 873
>> bytes, but then Emacs tries to access s->data[873].
>>
>> Does it look like I'm right in thinking that this is a bug in Emacs?
>
> This looks like a bug in emacs, as you say, but I don't know if it
> has any particular relation to the posix_memalign() changes.

Apparently it does seem related to posix_memalign() changes.
When I bootstrap Emacs without posix_memalign(), by manually
tweaking src/config.h after configure runs, and #undef
POSIX_MEMALIGN, then it passes the bootstrap stage normally.

> If updating to either before or after the broken
> posix_memalign() revision, and need help figuring out the
> issue, please let me know.

More issues come up after updating to today's CURRENT version of
malloc.  In particular:

    irssi started core dumping with symptoms similar to those of
    Emacs bootstrap, i.e. access to memory regions that are
    <inaccessible> in gdb

    xorg-server-snap is a requirement in FreeBSD/amd64, but it
    seems to trigger a panic and an insta-reboot with an ATI
    Radeon here.

Since this is the laptop I'm also using for every day work, I'll
try to revert back to the cvs -D '2006/01/12 07:28:20 UTC'
version for now.  Apart from looking at the source code, do we
have some sort of 'design' docs for the new malloc(), to see if I
can help debug these problems a bit more when I restore my
laptop's ports & packages from the backup later tonight?

- Giorgos