From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
cc: Alvaro Herrera <alvherre@alvh.no-ip.org>,
        Robert Haas <robertmhaas@gmail.com>,
        David Rowley <david.rowley@2ndquadrant.com>,
        Amit Langote <amitlangote09@gmail.com>,
        Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>,
        Jesper Pedersen <jesper.pedersen@redhat.com>,
        Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>,
        Beena Emerson <memissemerson@gmail.com>, amul sul <sulamul@gmail.com>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>,
        Dilip Kumar <dilipbalaut@gmail.com>
Subject: Re: [HACKERS] Runtime Partition Pruning
In-reply-to: <16007.1558711252@sss.pgh.pa.us>
References: <20180410213203.nl645o5vj5ap66sl@alvherre.pgsql>
 <d4903af2-e7b7-b551-71f8-3e4a6bdc2e73@2ndquadrant.com>
 <16007.1558711252@sss.pgh.pa.us>
Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Fri, 24 May 2019 11:20:52 -0400"
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Date: Fri, 24 May 2019 11:34:58 -0400
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I wrote:
> Peter Eisentraut <peter.eisentraut@2ndquadrant.com> writes:
>> What do people think about adding something like this errbacktrace()
>> from =C3=81lvaro's patch to core PostgreSQL?

> I think we did discuss it right after that, or somewhere nearby, and
> concluded that the output is so imprecise that it's not really going
> to be worth whatever portability issues we'd have to deal with.

Hmm, after some digging in the archives, the closest thing I can find
is this thread:

https://www.postgresql.org/message-id/flat/CAMsr%2BYGL%2ByfWE%3DJvbUbnpWtr=
RZNey7hJ07%2BzT4bYJdVp4Szdrg%40mail.gmail.com

where we discussed using libunwind instead, but people didn't like
the extra dependency.

However, I stand by the assertion that glibc's backtrace() is too
imprecise to be useful; I've experimented with it and despaired of
being able to tell where control had actually been.

			regards, tom lane