My impression was that for interfacing with hardware, the memory layout isn’t always contiguous, leaving gaps for reserved fields, so people just use the explic

My impression was that for interfacing with hardware, the memory layout isn’t always contiguous, leaving gaps for reserved fields, so people just use the explicit syntax shown in the article. I had been under the impression the layout of bit fields was guaranteed (much like struct fields) but if that is truly compiler specific as you say, I can see why it would not be useful for interfacing with hardware. I had always thought it was because embedded c sometimes deals with less capable compilers, so people often limit themselves to c89 or even older standards.