Re: Emacs 25.1 build failures on Ubuntu arm64

[Eli Zaretskii]

> From: Barry Warsaw <address@hidden>
> Date: Tue, 28 Mar 2017 20:30:40 -0400
> 
> I'm not sure how much of this email will be actionable, but I wanted to at
> least let y'all know about a problem we've seen building Emacs 25.1 on Ubuntu
> 17.04 arm64.

Did this configuration build correctly with Emacs 24.5?

> In any case, for several weeks now we've seen Emacs segfault on arm64 builders
> consistently in what I think are the CEDET tests.  The full traceback, when
> we've been able to capture it, is here:
> 
> https://launchpadlibrarian.net/302409391/gdb-bt-full.txt

I see this there:

  #5  handle_sigsegv (sig=11, siginfo=<optimized out>, arg=<optimized out>) at 
sysdep.c:1695
          fatal = <optimized out>
  #6  <signal handler called>
  No symbol table info available.
  #7  unchain_marker (address@hidden) at marker.c:605
          tail = <optimized out>
          prev = 0x676e696e6e6967e5
          b = 0x130acf0
  #8  0x00000000005334a4 in free_marker (address@hidden) at alloc.c:3850
  No locals.

The value of 'prev' in frame #7 looks garbled: it's ASCII text
"ginning", probably was "beginning" at some point.  This might
indicate memory corruption, either some dynamically allocated memory
or the stack got smashed.

Does your build compile ralloc.c?  If so, could you try configuring
with REL_ALLOC=no?

> and the bug that tracks this is here:
> 
> https://bugs.launchpad.net/ubuntu/+source/emacs25/+bug/1656474

That bug mentions several fixed done by Debian; did you try them?