is this the issue that you faced with latest llvm?

[Jorn Vernee]

Ah, sorry. This was left from when I was testing with allowing multiple 
different version, e.g. `grep -P "^(10|9|8)"` or similar. The default 
grep regex didn't seem to support that syntax, so I went with perl 
regex, and didn't realize this wouldn't work everywhere.

The -P option can just be removed for the current implementation. Maybe 
if we want to support multiple different version we will have to look 
into that again.

Jorn

Maurizio Cimadamore schreef op 2019-05-03 16:41:
> On 03/05/2019 15:38, Maurizio Cimadamore wrote:
>> seems like an issue with grep?
> 
> Yeah
> 
> -P, --perl-regexp
>               Interpret the pattern as a  Perl-compatible regular  
> expression
>               (PCRE).   This  is  highly  experimental and grep -P may 
> warn of
>               unimplemented features.
> 
> Why did you go for Perl-style?
> 
> Maurizio