Re: [PATCH v9 2/8] kbuild: add modules_thick.builtin

[Nick Alcock]

On 11 Nov 2022, Nick Alcock said:

> But... it's not quite doing the same thing, so perhaps it can't be that
> much simpler. Picking the first item that appears in my test build of
> this but not in modules_thick.builtin:
>
> +arch/x86/crypto/libblake2s-x86_64.o: arch/x86/crypto/blake2s-core.o arch/x86/crypto/blake2s-glue.o
>
> But...
>
> obj-$(CONFIG_CRYPTO_BLAKE2S_X86) += libblake2s-x86_64.o
> libblake2s-x86_64-y := blake2s-core.o blake2s-glue.o
>
> config CRYPTO_BLAKE2S_X86
>         bool "Hash functions: BLAKE2s (SSSE3/AVX-512)"
>
> This cannot be built as a module. The point of modules_thick.builtin was
> not to capture things that can be built into the kernel or left
> unconfigured entirely (though that is *also* a nice thing to capture,
> and should probably be captured regardless) but to capture *those things
> that can possibly be built as modules*, i.e. those things which are
> tristates in Kbuild and might possibly get built into .ko's. That was
> the whole reason we needed the tristate stuff in the first place, and
> I'm still not sure how to do it without that.

OK, I think I should be able to combine your patch with (a variant of)
the tristate stuff and get the best of both worlds (only-modular plus
the efficiency of building and simplicity of your patch, with no nasty
separate recursion like I had for modules_thick.builtin). Working on
that...