Re: [RFC PATCH v2 09/31] kvx: Add build infrastructure

[Jules Maselbas]

On Fri, Jan 20, 2023 at 03:39:22PM +0100, Arnd Bergmann wrote:
> On Fri, Jan 20, 2023, at 15:09, Yann Sionneau wrote:
> >      - Fix clean target raising an error from gcc (LIBGCC)
> 
> I had not noticed this on v1 but:
> 
> > +# Link with libgcc to get __div* builtins.
> > +LIBGCC	:= $(shell $(CC) $(DEFAULT_OPTS) --print-libgcc-file-name)
> 
> It's better to copy the bits of libgcc that you actually need
> than to include the whole thing. The kernel is in a weird
It was initialy using KCONFIG_CFLAGS which do not contains valid options
when invoking the clean target.

I am not exactly sure what's needed by gcc for --print-libgcc-file-name,
my guess is that only the -march option matters, I will double check
internally with compiler peoples.

> state that is neither freestanding nor the normal libc based
> environment, so we generally want full control over what is
> used. This is particularly important for 32-bit architectures
> that do not want the 64-bit division, but there are probably
> enough other cases as well.
> 
>      Arnd
> 
> 
> 
>