Well, the problem here is (assuming I'm understanding everything correctly) pretty specifically the combination of the comma operator and a bitfield. Of those

Well, the problem here is (assuming I'm understanding everything correctly) pretty specifically the combination of the comma operator and a bitfield. Of those two, I'd say the latter, even if superficially more intuitive, is probably the more obscure and advisable to avoid. The comma operator, while not all that common, can be pretty useful in common situations, and can easily achieve both clarity and conciseness. For example, to iterate over a singly-linked list while keeping a pointer to the previous item: for (prev = NULL, this = first; this != NULL; prev = this, this = this->next) { ... } I think this is a perfectly reasonable way to do things. Disallowing the comma operator due to an underspecified interaction with bitfields would be throwing out the baby with the bathwater, in my opinion.