From: Tom Lane <tgl@sss.pgh.pa.us>
To: exclusion@gmail.com
Cc: pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #16814: Invalid memory access on regexp_match with .* and BRE
Date: Fri, 08 Jan 2021 12:19:46 -0500
Message-ID: <323716.1610126386@sss.pgh.pa.us> (raw)
In-Reply-To: <16814-6c5e3edd2bdf0d50@postgresql.org>
References: <16814-6c5e3edd2bdf0d50@postgresql.org>
PG Bug reporting form <noreply@postgresql.org> writes:
> When executing the following regexp call:
> select regexp_match('abc', '.*', 'b');
> valgrind detects an error:
Hah, nice one. It gives the wrong answer too, at least it does most of
the time for me:
# select regexp_match('abc', '.*', 'b');
regexp_match
--------------
{""}
(1 row)
That's because it's acting like the pattern is '.*?' (prefer shortest
match) rather than '.*'.
This bug is well over the age of consent, btw. Tcl's got it too,
so it surely is aboriginal in Henry Spencer's code.
Thanks for the report!
regards, tom lane
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Subject: Re: BUG #16814: Invalid memory access on regexp_match with .* and BRE
In-Reply-To: <323716.1610126386@sss.pgh.pa.us>
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