Re: [PATCH 1/2] kbuild: create built-in.o automatically if parent directory wants it

[Sam Ravnborg]

Hi Masahiro.

Thanks for picking this up.

> A key point is, the parent Makefile knows whether built-in.o is needed
> or not.  If a subdirectory needs to create built-in.o, its parent can
> tell the fact when Kbuild descends into it.
Good observation!
> 
> diff --git a/Makefile b/Makefile
> index 008a4e5..cc0b618 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1003,7 +1003,7 @@ $(sort $(vmlinux-deps)): $(vmlinux-dirs) ;
>  
>  PHONY += $(vmlinux-dirs)
>  $(vmlinux-dirs): prepare scripts
> -	$(Q)$(MAKE) $(build)=$@
> +	$(Q)$(MAKE) $(build)=$@ need-builtin=1

The need-bultin may also be required for the shortcuts
that allows one to use:

	make <dir>/

    example:

	make net/

And maybe selftest, documentation shortcuts too?
Other than that - looks good.

Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx>

	Sam