Re: bug#20657: Accepting [xyz---abc] - three minus signs to mean one

[Paul Eggert]

On 4/24/22 06:21, arnold@skeeve.com wrote:
> I plan to add a test to gawk; perhaps grep would benefit from one as well?

That'd need more than just a test, as we'd need to also modify regex.m4 
to arrange to replace any system regex that has this incompatibility 
with gnulib regex. And we'd need to document the extension since we 
shouldn't test undocumented features. Although such work could be done, 
I expect it'd be a more productive use of our limited time to get this 
extension into glibc first. I'll add that to my (long) list of things to do.