bug#44047: current HEAD has been crashing on startup

[Eli Zaretskii]

> Date: Sat, 17 Oct 2020 11:06:23 -0600 (MDT)
> From: Liam Stitt <stittl@cuug.ab.ca>
> 
> 
> I waited a few days before reporting this because I'm not sure how much 
> useful information I can provide in this report, but it hasn't been 
> mentioned by anyone else, so here goes.
> 
> Running ./emacs in src/ within gdb (invoking it with -Q), I'm getting:
> 
> Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
> 
> Program received signal SIGSEGV, Segmentation fault.
> 
> build_frame_matrix_from_leaf_window (w=0x555555b8c140,
>      frame_matrix=<optimized out>) at dispnew.c:2531
> 2531          fill_up_frame_row_with_spaces (frame_row, 
> window_matrix->matrix_x);
> 
> This is on a Linux 5.7 kernel, Debian unstable, x86-64, but I can 
> replicate it on a raspi running 5.4 and stable.
> 
> It appears to be related to -nw somehow; using that triggers the crash on 
> the Pi (otherwise it starts up normally).

You are saying that "./src/emacs -Q -nw" crashes on startup?  That
doesn't happen to me with today's master branch.

Can you build an unoptimized version, run it under GDB, and when it
crashes, show a backtrace?