On Sat, Sep 19, 2026 at 06:02:46PM +0100, Lorenzo Stoakes (ARM) wrote: > On Thu, Sep 17, 2026 at 01:59:26PM -0700, Kees Cook wrote: > > So, yeah, it makes me nervous, and it may make incremental builds less > > idempotent. But I can't really find extant problems and the demo is > > slightly contrived, but not exactly an impossible situation. > > Ack thanks for this! > > There is definitely an issue here, your example is fine in the stock kernel > but one run late in v3. > > Solution is to have depcheck treat any dependency that is itself a target > of the same run as never being 'fresh' (it already reads every .cmd file in > the directory so has all the dependency information it needs), so that's > fixed in v4. > > Confirmed that it fixes the demo'd bug here, that touching a header > rebuilds exactly the same objects as it did before and that noop build perf > was not harmed by the change.
Oh very nice! Thank you for finding a solution there. :) -- Kees Cook
