Re: Regular expression libraries

[Paul Eggert]

On 12/15/2016 11:00 AM, Clément Pit--Claudel wrote:
> I've had a quick look at the existing options.  Here's what I gathered (the 
> list below includes only libraries whose licensing is compatible with Emacs):
>
> * There are only two usable, non-backtracking regexp libraries:
>    - RE2 ...
>    - TRE ...

Another library is in that list:

  - The GNU C library, which ordinarily uses a DFA but which uses 
backtracking if needed.

That is, the current glibc implementation is now quite different from 
the old version that the Emacs matcher is derived from.