Re: [PATCH] iomap: hide iomap_sector with CONFIG_BLOCK=n

[Masahiro Yamada]

On Fri, Jul 19, 2019 at 11:24 AM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
>
> On 7/18/19 7:19 PM, Masahiro Yamada wrote:
> > Hi.
> >
> > On Thu, Jul 18, 2019 at 11:28 PM Darrick J. Wong
> > <darrick.wong@xxxxxxxxxx> wrote:
> >>
> >> On Thu, Jul 18, 2019 at 03:08:35PM +0200, Christoph Hellwig wrote:
> >>> On Thu, Jul 18, 2019 at 03:03:15PM +0200, Arnd Bergmann wrote:
> >>>> The inclusion comes from the recently added header check in commit
> >>>> c93a0368aaa2 ("kbuild: do not create wrappers for header-test-y").
> >>>>
> >>>> This just tries to include every header by itself to see if there are build
> >>>> failures from missing indirect includes. We probably don't want to
> >>>> add an exception for iomap.h there.
> >>>
> >>> I very much disagree with that check.  We don't need to make every
> >>> header compilable with a setup where it should not be included.
> >>
> >> Seconded, unless there's some scenario where someone needs iomap when
> >> CONFIG_BLOCK=n (???)
> >
> > I agree.
> >
> > There is no situation that iomap.h is included when CONFIG_BLOCK=n.
> > So, it is pointless to surround offending code with #ifdef
> > just for the purpose of satisfying the header-test.
> >
> >
> > I started to think
> > compiling all headers is more painful than useful.
> >
> >
> > MW is closing, so I am thinking of disabling it for now
> > to take time to re-think.
> >
> >
> > diff --git a/init/Kconfig b/init/Kconfig
> > index bd7d650d4a99..cbb31d134f7e 100644
> > --- a/init/Kconfig
> > +++ b/init/Kconfig
> > @@ -111,6 +111,7 @@ config HEADER_TEST
> >  config KERNEL_HEADER_TEST
> >         bool "Compile test kernel headers"
> >         depends on HEADER_TEST
> > +       depends on BROKEN
> >         help
> >           Headers in include/ are used to build external moduls.
> >           Compile test them to ensure they are self-contained, i.e.
> >
> >
> >
> > Maybe, we should compile-test headers
> > only when it is reasonable to do so.
>
> Maybe.  But I would find it easier to use if it were a make target
> instead of a Kconfig symbol, so someone could do
> $ make compile_test_headers


You can do equivalent with this:

$ ./scripts/config -e HEADER_TEST
$ make include/


-- 
Best Regards
Masahiro Yamada