On Sat, Feb 20, 2016 at 8:19 PM, Jim Meyering <jim@meyering.net> wrote:
...
>> The bug also present with PCRE engine:
>>
>>    $ printf '12\n34\0' | LC_ALL=en_US.utf-8 grep -z -P '^[1234]*$' | wc -c
>>    6
>>    $ printf '12\n34\0' | LC_ALL=en_US.utf-8 grep -z -P '^[1-4]*$' | wc -c
>>    6
>
> Thank you for the analysis and the report.
> I have fixed the regex-oriented problem with the attached
> patch, but not yet the case using -P -z (PCRE + --null-data):

FTR, I've also pushed the attached test-improving patch: