Re: branch master segfault (2019-02-05)

[Eli Zaretskii]

> From: Philippe Vaucher <address@hidden>
> Date: Wed, 6 Feb 2019 17:23:11 +0100
> Cc: Emacs developers <address@hidden>
> 
>  > I know docker allocates a "pseudo TTY", so probably that there's a 
> misdetection happening here.
> 
>  No, it isn't misdetection.  The problem is that safe_terminal_coding
>  is not set up.
> 
> Your patch works, thanks!
> 
> Just curious, does that mean that in "normal terminals" (not docker) it uses 
> `FRAME_TERMINAL_CODING (f)
> ` but in docker it uses `safe_terminal_coding`?

Looks like that, yes.  It would mean that the docker doesn't define a
locale environment which defines a usable codeset.  I know nothing
about dockers, so I have no idea how could this happen.

> If yes, why does it also work in Docker when using `FRAME_TERMINAL_CODING 
> (f)`?

Because the terminal encoding was set up, whereas safe_terminal_coding
wasn't.  In Emacs 26, safe_terminal_coding kept its value initialized
in temacs and recorded by unexec, but with pdumper that doesn't
happen, so safe_terminal_coding started as all-zero, as any other
static variable.