Hi Paul. > > As a point of information, it does happen for gawk. > > Could you please say where that happens? I just now looked at the gawk > trunk, and the only two places I saw it calling dfaexec > (helpers/testdfa.c and re.c), it passed a nonnull backref argument.
OK, I was wrong and spoke without checking. My point was that the code in question is buggy for gawk. I suspect that the reason gawk always passes non-null backref may be that at one time the pointer had to be valid. I tried it by passing a NULL pointer and only one of the tests in the test suite fails; no time right now to investigate more, but it might be possible for gawk to pass NULL and have it work. > Obviously this revert does reintroduce the bug with [\]-\]] that you > mentioned with Awk regular expressions. It reintroduces similar bugs > for GNU grep. At the very least we should fix that. I'll follow up with > a patch. Looking forward to this. Grep has general RRI problems. I think the grep team needs to decide if RRI is important for grep or not, and if so whether it is more important than collating sequences and equivalence characters. I think everyone knows how I feel about these issues. If not, I will expound further. Thanks, Arnold
