Ouch. I'm pretty sure that the compiler I worked on 22 years ago could stop at sequence points, e.g. after the evaluation of the LHS of && and ||. (OK, actually it was a superset of those, called "gesornenplatz points" in-house, but that's another story.)

Ignoring the "no space after if/while/for" issue, I'd suspect that code to not have been the author's intent if I just came across it.