Re: [PATCH 2/2] kconfig: do not write .config if the content is the same

[Masahiro Yamada]

On Fri, May 10, 2019 at 3:21 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Fri, May 10, 2019 at 03:12:05PM +0900, Masahiro Yamada wrote:
> > Kconfig updates the .config when it exits even if its content is
> > exactly the same as before. Since its timestamp becomes newer than
> > that of other build artifacts, additional processing is invoked,
> > which is annoying.
> >
> > - syncconfig is invoked to update include/config/auto.conf, etc.
> >
> > - kernel/config.o is recompiled if CONFIG_IKCONFIG is enabled,
> >   then vmlinux is relinked as well.
> >
> > If the .config is not changed at all, we do not have to even
> > touch it. Just bail out showing "No change to .config".
> >
> >   $ make allmodconfig
> >   scripts/kconfig/conf  --allmodconfig Kconfig
> >   #
> >   # configuration written to .config
> >   #
> >   $ make allmodconfig
> >   scripts/kconfig/conf  --allmodconfig Kconfig
> >   #
> >   # No change to .config
> >   #
> >
> > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
>
> Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> ?

OK.

For reviewers who do not know the context,
please see this comment from Linus:

https://lkml.org/lkml/2019/5/9/983



-- 
Best Regards
Masahiro Yamada