Subject: Re: bug#25172: 26.0.50; Concurrency feature, sit-for doesn't work (crashing and unexpected behaviour)

From: Andreas Schwab <[email-masked]>
Date: Tue, 13 Dec 2016 19:25:19 +0100

On Dez 13 2016, Eli Zaretskii <[email-masked]> wrote:

> There's something here I don't understand.  It looks like 9 threads
> are stuck in acquire_global_lock, which is fine.  The main thread was
> executing some timer (probably, the one set up by global-eldoc-mode),
> when it was delivered SIGSEGV.  There's one more thread running this:
>
>   Stack trace of thread 23775: 
>   #0 0x00007f5687e5e426 __sigsuspend (libc.so.6) 
>   #1 0x0000000000578385 deliver_thread_signal (emacs-26.0.50) 
>   #2 0x00000000005783f8 deliver_fatal_thread_signal (emacs-26.0.50) 
>   #3 0x00000000005785ae handle_sigsegv (emacs-26.0.50) 
>   #4 0x00007f5688810080 n/a (libpthread.so.0) 
>
> This seems to be some thread, which was hit by SIGSEGV, and since it
> is not the main thread, it calls pdthread_kill to kill the main
> thread, which explains why the main thread received the signal.  But
> what I don't understand is what was this thread 23775 doing before it
> hit SIGSEGV?  The backtrace stops at handle_sigsegv, without revealing
> that.

Installing debuginfo for glibc and/or `thread apply all bt' will most
likely give more information.

Andreas.

-- 
Andreas Schwab, [email-masked]
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."