On Thu, Aug 26, 2010 at 05:15:35PM +0200, Arnd Bergmann wrote: > On Wednesday 25 August 2010, Hollis Blanchard wrote: > > > We only recently fixed the kernel to have this warning in types.h, which > > > triggers more often than kernel.h, where it used to be before. In 2.6.35 > > > and before, you consequently would not have noticed the problem. > > > > > > > Thanks Arnd, that explains it. > > > > It looks like the --kerneldir option needs to be re-thought. > > Yes. I believe that we should just kill that option, since there is > no reason for building with set of headers from a different kernel > than the one your glibc normally uses.
As others pointed out, it's very useful for development. I would suggest we do what qemu-kvm.git does instead, and keep a copy of some headers in qemu tree. This way developer just copies the header into qemu tree, and we can get rid of a bunch of ifdefs in code. > You obviously need copies of some headers to match qemu code, e.g. > the kvm headers, but for those we have run-time compatibility code > in qemu. Building with a newer kernel header is pointless because > qemu would not use any of the features that were added after the > release of the qemu tree you are trying to build. Building with > an older kernel header is equally pointless because all it would > do is to require #ifdef magic in qemu that ends up preventing you > from using all features of new kernels. > > Arnd
