On Fri, Jul 06, 2018 at 11:13:02PM +0900, Masahiro Yamada wrote: > >> LDFLAGS is for internal-use. > >> Please do not override it from the command line. > > > > Can we generate a build error if a user try to override LDFLAGS, CFLAGS or > > other critical internal-use-only variables? > > Yes, Make can check where variables came from.
I think we should do this. > >> make LDFLAGS_KERNEL=... LDFLAGS_MODULE=... > >> will allow you to append linker flags. > > > > Okay. It makes me wounder if we should taint kernel in such cases? > > Custom compiler/linker flags are risky and can lead to weird bugs. > > OK. > So, what problem are we discussing? Users set custom LDFLAGS/CFLAGS and break kernel. Then report bug that hard to debug. See https://bugzilla.kernel.org/show_bug.cgi?id=200385 and start of this thread: https://lore.kernel.org/lkml/20180701213243.ga20...@trogon.sfo.coreos.systems/ It took me a while to track down the issue. I blamed linker for a while. > > I've got it wrong. *Any* LDFLAGS option passed to make this way: > > > > make LDFLAGS="..." > > In your previous mail, I thought you were asking me how to pass > custom linker flags. > > If not, we do not need to think about that case. > Just say "Do not do that". At least we need to make user aware about risk of setting custom flags. -- Kirill A. Shutemov
