Re: Crash report for some ICU-52 (debian8) COLLATE and work_mem values

Tom Lane wrote:

> The other class of failures amounts to this loop iterating till it falls
> off the end of memory:
>
> while(schar > (tchar = *(UCharOffset+offset))) { /* since the
> contraction codepoints should be ordered, we skip all that are smaller */
> offset++;
> }
>
> which is unsurprising, because (in my core dump) schar is 1113834 which is
> larger than any possible UChar value, so the loop cannot terminate except
> by crashing. The crash occurred while trying to process this string:
>
> buf2 = 0x1614d20 "requ\364\217\273\252te",
>
> and I do not think it's coincidence that that multibyte character
> there corresponds to U+10FEEA or decimal 1113834. Apparently
> they've got some bugs with dealing with characters beyond U+FFFF,
> at least in certain locales.

For that failure, this single comparison seems to hit it consistently
with ICU-52:

# SELECT 'ab' < 'abc'||chr(128519) COLLATE "bs-x-icu";

server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.

128519 is 'SMILING FACE WITH HALO' (U+1F607), and nearby codepoints
cause the same bug.

At least from this simple test we can produce a bug report
to the maintainers who are still interested in pre-53 versions.

Best regards,
--
Daniel Vérité
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