pdumper on Solaris 10

[Pip Cet via "Emacs development discussions." <emacs-devel@gnu.org>]

"Po Lu" <luangruo@yahoo.com> writes:

> pdumper-dumped binaries appear to crash in an x86 Solaris 10 zone,
> though I don't really use this configuration and I'm not interested in
> trying the portable dumper on sparc:
>
> core 'core' of 7021:        ../../src/bootstrap-emacs -batch --no-site-file --no-site-lisp -f batc
>  00007fffaf433dc2 ???????? ()
>  00007fffaf5eb3d7 ???????? ()
>  00007fffaf5ec590 ???????? ()
>  00007fffae3f351a _lwp_kill () + a
>  00007fffae3981b9 raise () + 19
>  00000000008baf90 terminate_due_to_signal () + c0
>  000000000090236e ???????? ()
>  0000000000902334 deliver_thread_signal () + 74
>  00000000009023b0 deliver_fatal_thread_signal () + 10
>  00000000009024ef handle_sigsegv () + 4f
>  00007fffae3edd16 __sighndlr () + 6
>  00007fffae3e25e2 call_user_handler () + 252
>  00007fffae3e280e sigacthandler () + ee
>  00007fffaf5ea82d ???????? ()
>  ffffffffffffffff ???????? ()
>  00000000009c77e7 lisp_align_malloc () + 4d7
>  00000000009c9dd2 make_float () + 42
>  00000000009d2e9d init_alloc () + d
>  00000000008bd373 main () + bb3
>  00000000006d15ab ???????? ()

FWIW, this issue doesn't appear to happen on a "fresh" Solaris 10
install, in a qemu virtual machine, on x86.  I used the
sol-10-u11-ga-x86-dvd.iso image, installed to a new disk, then installed
OpenCSW and built Emacs from the master branch with and without
CFLAGS="-m64" (plus the linker path selection). Both builds appear to
work.

What's odd about that backtrace is that lisp_align_malloc in the current
build is only 435 bytes long (with -m64), so it's hard to guess
which part of the alignment code used to be at offset 0x4d7.

But while we're talking about rare and unusual systems, !USE_LSB builds
are currently broken except for the WIDE_EMACS_INT case, because the
stack scanning code makes no attempt to remove MSB tags.  It may be time
to simply remove MSB tag support, unless there are systems around that
actually fail to align static objects to 8-byte boundaries (but such
systems would have been broken for a while now).

Pip