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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Mark Dilger <mark.dilger@enterprisedb.com>
cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: Assert triggered during RE_compile_and_cache
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Comments: In-reply-to Mark Dilger <mark.dilger@enterprisedb.com>
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Mark Dilger <mark.dilger@enterprisedb.com> writes:
> +select '' ~ '(())(\2){0}';
> +server closed the connection unexpectedly

> Any ideas?

Huh.  This seems like some deficiency in the part of parseqatom
starting with

	/* annoying special case:  {0} or {0,0} cancels everything */
	if (m == 0 && n == 0)

but I don't immediately see what's different about your failing case
versus the not-failing ones.

			regards, tom lane