Re: [RFC PATCH v3 0/2] rust: crates in other kernel directories

From: Masahiro Yamada
Date: Mon Feb 19 2024 - 04:07:14 EST


On Mon, Feb 19, 2024 at 1:11 AM Martin Rodriguez Reboredo
<yakoyoku@xxxxxxxxx> wrote:
>
> On 11/13/23 11:13, Masahiro Yamada wrote:
> > [...]
> >
> > I will not provide a line-by-line review.
> >
> >
> > Just one thing I'd like to point out.
> >
> > You assume the library (drivers/usb/core/*)
> > is built before its consumers (samples/rust/*).
> >
> > If Kbuild ends up with building lib consumers first,
> > it will be a build error.
> >
> >
> >
> > Kbuild descends into multiple directories in parallel building.
> >
> > You cannot predict which directory is built first.
> >
> > [...]
>
> Thinking with what you've said the same thing might apply to any Rust
> written code that depends on crates under the `rust` dir. Adding
> Make dependencies to object code made from `.rs` will be required if so,
> assuming that Kbuild is intelligent enough to build the crates first.


rust/Makefile specifies dependencies between crates.

I do not know how to specify crate dependencies
across multiple Makefiles, like you did in
drivers/usb/core/Makefile and samples/rust/Makefile.



--
Best Regards
Masahiro Yamada