bug#34910: 27.0.50; Too much matching reentrancy

[Stefan Monnier]

>> By the way, is there any reason why only calls to re_search_2 are made
>> with a busy-marked regexp buffer, not calls to re_search? Are the
>> latter guaranteed not to be reentrant?
> Not sure.  Stefan, any thoughts?

It was probably just an oversight, because whether we're searching
within strings or within buffers the same problems appear with \{N\}
repetitions (where the counter is stored directly inside the
regexp-byte-code) and with on-the-fly strength-reduction (where we
replace some byte-code with cheaper ones (where applicable) on the first
pass through the regexp).


        Stefan