In my understanding, other implementations cannot perform better, because the root cause is how it is defined in the standard. Basically, any better implementat

In my understanding, other implementations cannot perform better, because the root cause is how it is defined in the standard. Basically, any better implementation would be non-conforming. It’s not the kind of ABI issue where simply choosing a different one would help; the flaw comes directly from the definition, which cannot be changed. Of course, non-std implementations of regexes in C++ don’t have this issue. Were strictly talking about the standard library one.