Nice! I already knew that CLang provides a better warning/error messages, as well as helping find some issues without the need of some other lint software, but I had no idea that it tried to optimize the output from bison et al!
OK, I'll update the note with this in mind.
The problem is that optimizing the parser for swak is futile: the time spent doing the actual parsing is small compard to the actual "OF-work": calculations on the fields. That's why I added the special optimiziation switch for the parsers.
PS: and this "tries to optimize goto-stained code" is only a theory (I haven't looked at the source. But its behaviour - certain CLang versions freeze a 8 Gig machine when compiling FieldParser with O3 - make me pretty sure that this is the case)