Re: [PATCH 0/2 v3] Demangler crash handler

[Mark Kettenis <mark dot kettenis at xs4all dot nl>]

> Date: Wed, 4 Jun 2014 11:07:55 +0100
> From: Gary Benson <gbenson@redhat.com>
> 
> Hi all,
> 
> This patch is an updated version of the demangler crash handler I
> posted two weeks ago.  There are two main changes from the previous
> version:
> 
>  1) The signal handler creates a core file before returning.
>     This ensures that a core file is created at the correct
>     location.
> 
>  2) I have switched the crash handler to be enabled by default.
>     I think this is appropriate now that a core file is always
>     created.
> 
> To make this work correctly I have had to add a new class of
> internal problem, which I've called demangler_warning.  This
> has the same behaviour as internal_warning except that it does
> not prompt the user to create a core file because that's already
> been done.  I know Doug didn't want this but it's necessary to
> avoid either overwriting the useful core file with a non-useful
> one or confusing the user with a second, non-useful core file.
> 
> I've split this patch into two parts for ease of discussion.  The
> first patch adds the new internal problem functionality, and the
> second patch is the crash handler itself.  This differs from the
> previous version by the addition of core file generation and in
> that it calls demangler_warning instead of internal_warning.
> 
> I would push both patches as one commit.  The news file entries
> for the commit would be:
> 
>   * New options
>   
>   maint set catch-demangler-crashes (on|off)
>   maint show catch-demangler-crashes
>     Control whether GDB should attempt to catch crashes in the symbol
>     name demangler.  The default is to attempt to catch crashes.  If
>     enabled, the first time a crash is caught, a core file is created,
>     the offending symbol is displayed and the user is presented with
>     the option to terminate the current session.
>   
>   maint set demangler-warning quit (yes|no|ask)
>     When GDB catches a crash in the symbol name demangler it can offer
>     the user the opportunity to both quit GDB and create a core file of
>     the current GDB session.  These options control whether or not to
>     do either of these.  The default is to create a core file and to ask
>     the user whether to quit.
>   
>   * New commands
>   
>   maint demangler-warning
>     Cause GDB to call the internal function demangler_warning and
>     hence behave as though an internal error in the demangler has
>     been detected.
> 
> Is this ok to commit?

Not for me.  You're running too much code between entering the SIGSEGV
handler and dumping core for my taste.

I still very much agree with Pedro; this should not be necessary.
Drop this.  Spend your time on fixing the actual bugs.