Re: [PATCH v18 01/10] idr: add #include <linux/bug.h>

[Michal Hocko]

On Wed 29-11-17 16:58:17, Matthew Wilcox wrote:
> On Wed, Nov 29, 2017 at 09:55:17PM +0800, Wei Wang wrote:
> > The <linux/bug.h> was removed from radix-tree.h by the following commit:
> > f5bba9d11a256ad2a1c2f8e7fc6aabe6416b7890.
> > 
> > Since that commit, tools/testing/radix-tree/ couldn't pass compilation
> > due to: tools/testing/radix-tree/idr.c:17: undefined reference to
> > WARN_ON_ONCE. This patch adds the bug.h header to idr.h to solve the
> > issue.
> 
> Thanks; I sent this same patch out yesterday.
> 
> Unfortunately, you didn't cc the author of this breakage, Masahiro Yamada.
> I want to highlight that these kinds of header cleanups are risky,
> and very low reward.  I really don't want to see patches going all over
> the tree randomly touching header files.  If we've got a real problem
> to solve, then sure.  But I want to see a strong justification for any
> more header file cleanups.

I agree. It usually requires unexpected combination of config options to
uncover some nasty include dependencies. So these patches might break
build while their additional value is quite questionable.
-- 
Michal Hocko
SUSE Labs