PCRE2 interim release 2 requested to support grep 3.11

[Brian Inglis]

On 2023-05-20 12:16, Achim Gratz via Cygwin-apps wrote:
> Brian Inglis via Cygwin-apps writes:
>> Because of issues with the current release of PCRE2 Unicode matching
>> in latest grep 3.11 release reverting to ASCII only matches for some
>> patterns, it would be good to have an updated interim Cygwin release 2
>> of PCRE2 10.42+ available incorporating PCRE2_EXTRA_ASCII_... changes,
>> and for PCRE2_MATCH_INVALID_UTF, between Feb 1 and April 21, submitted
>> by Carlo Arenas for pcre2 and grep.
> 
> That patch set is apparently still not merged upstream and other work in
> this area is still going on, so I don't think it's wise to jump the gun.

It appears that carenas has applied the patches to pcre2 and grep to "fix" the 
issue in either case by testing the pcre2 implementation during configuration.

>> Otherwise we could not upgrade grep until pcre2 10.43 is released.

> Yes, we can just wait for uptstream to sort things out.

Given that there are currently grep -P bugs in 3.10 "fixed" in 3.11, should we 
then revert grep -P to 3.8 level, drop Unicode pattern support, and support only 
ASCII?
It is unclear to me from the description if only the escape sequence patterns 
are affected, or also the [[:...:]] character and [[=?=]] equivalence classes, 
and Unicode properties \p{prop} \P{prop}?

-- 
Take care. Thanks, Brian Inglis              Calgary, Alberta, Canada

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry