“Robert Day proposed a couple of new kernel code maturity
configuration options for tagging code as either ‘deprecated’ or
‘obsolete.’ He referenced earlier confusion around the attempt to
remove devfs in which it wasn’t clear on the current state and
future plans for the code. He explained, ‘using deprecated code is
still technically fine, but using obsolete code should be something
that raises a red flag of some kind.’ Aside from a little confusion
between the differences in definition between these two words,
general feedback was positive. H. Peter Anvin supported the patch,
‘if nothing else, it gives some middle-of-the-roadness to the
continual ‘to remove or not to remove’ debate.’ Robert also noted
that the ‘deprecated’ flag would be a useful sanity check when
building a kernel, ‘this would seem to be a quick and dirty way to
prune anything that is *supposed* to be obsolete from the build, to
make sure you’re not picking up dead code by accident…'”