From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 5231A3858D28; Tue, 17 Jan 2023 19:37:02 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5231A3858D28
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1673984222;
	bh=oAlZXCpymSCznnD1bviVgt9eZ8N36CcVIyFCGI8GpIE=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=ZHpiugSikh/fd8xC1IcOMi0u2d/0VskGCMI4sZPydL7v0yGFlN1THqxy5heIt2U3g
	 MOrszMmYWhFN2nbmNf1Te7WumQoSuo/HAUMFHxmwIjGJNsgN7xwjpMcm3Gy1mk8ZIA
	 hYR7VOyQRhV59NSK6A9IQW95MgUEffYRK9WF8KSE=
From: "gustaf.waldemarson at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug debug/107965] libstdc++ Python Pretty-Printers: Many Exceptions
 From Uninitialized Structures
Date: Tue, 17 Jan 2023 19:37:01 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: debug
X-Bugzilla-Version: unknown
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: gustaf.waldemarson at gmail dot com
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-107965-4-FdFPLgkGXT@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-107965-4@http.gcc.gnu.org/bugzilla/>
References: <bug-107965-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107965

--- Comment #7 from Gustaf Waldemarson <gustaf.waldemarson at gmail dot com=
> ---
Very interesting to see so many people chime in on this. Since I arguably
agree that this looks like a GDB bug than an error in the printers. To that
end, I went ahead and registered this
[ticket](https://sourceware.org/bugzilla/show_bug.cgi?id=3D30018) here. Ple=
ase
feel free to add
some more details if you have time, as some of the details presented here is
admittedly a bit beyond my skills.

All that said, I still think that the pretty printers should be a bit more
defensive to errors and conservative with what it outputs. E.g., presenting=
 an
error message once, due to something like this is fine in my opinion, but
displaying hundreds of lines with the same error just because some function
uses a hash-map is clearly excessive.

To that end, perhaps it would make sense to defend the `to_string`=C2=A0cal=
ls (and
possibly others) with something like this:

    seen_errors =3D {}
    # ...
    try:
        to_string(...)
    except Exception as ex:
        if ex not in seen_errors:
            seen_errors.add(ex)
            raise ex

Admittedly, I don't know all the details here, so perhaps this isn't feasib=
le?=