Re: Why this regexp matches?!

Alban Hertroys <haramrae@gmail.com> writes:
> On 4 Feb 2012, at 9:46, hubert depesz lubaczewski wrote:
>> select 'depesz depeszx depesz' ~ E'^(.*)( \\1)+$';

> Apparently something odd is going on between the wildcard, the repetitive part and the back-reference. That could be
justus not seeing what's wrong with the expression or be an actual bug. 

FYI, I've made some progress on characterizing the cause of this bug,
as per comments at the upstream bug report:
https://sourceforge.net/tracker/index.php?func=detail&aid=1115587&group_id=10894&atid=110894
There are actually two distinct bugs involved, and I don't yet have a
patch for the case depesz illustrates.

            regards, tom lane