[m-rev.] for review: Initial support for cross-compiling using clang.

[Julien Fischer]

On Mon, 18 Jul 2022, Peter Wang wrote:

> [I will rename README.cross to README.cross-gcc in a separate change.]

I would be inclined to rename it to README.cross-gcc.md (and similarly
for the clang version), so that people viewing it on github see the
formatted version**.  (I've been meaning to do that the all of the
README file, but just haven't got around to it yet.)

(** At least I would be so inclined were either file properly
Markdownified.)

> ---
>
> README.cross-clang:
> .nocopyright:
>    Add instructions for cross-compiling using clang.
>
> README.cross:
>    Clarify this document discusses cross-compilation using gcc.
>
> README.md:
>    Add reference to new readme.
>
> tools/configure_cross:
>    Adapt script to support a FreeBSD x86-64 target using clang.
>
> NEWS:
>    Announce change to script.

That looks fine.

Julien.