bug#36677: [PATCH] Don't truncate backtraces

[Mark H Weaver <mhw@netris.org>]

Hi Robert,

Robert Vollmert <rob@vllmrt.net> writes:

> * module/system/repl/debug.scm (print-frame): Print full object if
> width keyword is #f.
> * libguile/backtrace.c (display_backtrace_body): Call print-frames
> with #:width #f.
> ---
>
> This change was prompted by recent discussion on the Guix lists:
>   https://lists.gnu.org/archive/html/guix-devel/2019-07/msg00207.html
> In Guix, the truncation of stack traces frequently obscures
> important information due to the long filenames.

I'm sympathetic to this problem, but simply disabling the truncated
printing during backtraces is not workable.  It is quite often the case
that some of the structures printed in backtraces are *huge*, or even
cyclic.

Have you tried setting the COLUMNS environment variable to a larger
value?  I'd prefer a solution along those lines, where the user can set
an environment variable to ask for less truncation in backtraces.

     Thanks,
       Mark