On Wed, Dec 6, 2023, 9:55 PM Simon J. Gerraty <[email protected]> wrote:
> Jessica Clarke <[email protected]> wrote: > > > Warner Losh <[email protected]> wrote: > > >> Silly question: why not just add it to CFLAGS with > > >> -DOSNAME=\"${OSNAME}\" rather than generating this file? > > > > > > Actually it is an excellent question - I've no idea why opt_osname.h is > > > needed. > > > > To quote the motivation from brd@’s original review: > > > > > The reason I did it using a file is so that make(1) would detect a > > > change a rebuild if you change the value and do another build. > > A fair point. Of course moot if using META_MODE. > The other benefit of the header is only the files that include it will > be rebuilt when the value changes whereas (with META_MODE) everything > will be rebuilt if value is in CFLAGS. > > That can be mitigated by using per object CFLAGS, but all in all the > header is a simpler solution. > This name never changes on practice. We shouldn't optimize for a rare case that causes build races. Who would ever change it in the same tree? Warner --sjg >
