If RUST_LIB_SRC is defined in the top-level Makefile (via an environment
variable or command line), it is already exported.

The only situation where it is defined but not exported is when the
top-level Makefile is wrapped by another Makefile (e.g., GNUmakefile).
I cannot think of any other use cases.

I know some people use this tip to define custom variables. However,
even in that case, you can export it directly in the wrapper Makefile.

Example GNUmakefile:

    export RUST_LIB_SRC = /path/to/your/sysroot/lib/rustlib/src/rust/library
    include Makefile

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
This code was added by this commit:

  https://github.com/Rust-for-Linux/linux/commit/3f46885dc03ed2d750085b2237078a1628323964

Please me know if I am missing something.


 Makefile | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/Makefile b/Makefile
index d57cfc6896b8..b194b7702a2e 100644
--- a/Makefile
+++ b/Makefile
@@ -578,10 +578,6 @@ else
 	RUSTC_OR_CLIPPY = $(RUSTC)
 endif
 
-ifdef RUST_LIB_SRC
-	export RUST_LIB_SRC
-endif
-
 # Allows the usage of unstable features in stable compilers.
 export RUSTC_BOOTSTRAP := 1
 
-- 
2.43.0

On Fri, Sep 13, 2024 at 8:06 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> This code was added by this commit:
>
>   https://github.com/Rust-for-Linux/linux/commit/3f46885dc03ed2d750085b2237078a1628323964
>
> Please me know if I am missing something.

I think it is OK -- unless Fiona recalls something:

Acked-by: Miguel Ojeda <ojeda@kernel.org>
Tested-by: Miguel Ojeda <ojeda@kernel.org>

Thanks Masahiro for the simplification!

Cheers,
Miguel

On 24 Sep 2024, at 20:42, Miguel Ojeda wrote:

> On Fri, Sep 13, 2024 at 8:06 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
>>
>> This code was added by this commit:
>>
>>  https://github.com/Rust-for-Linux/linux/commit/3f46885dc03ed2d750085b2237078a1628323964
>>
>> Please me know if I am missing something.
>
> I think it is OK -- unless Fiona recalls something:

As long as the export to rustc and the rust analyzer script works this looks good.

Acked-by: Fiona Behrens <me@kloenk.dev>

>
> Acked-by: Miguel Ojeda <ojeda@kernel.org>
> Tested-by: Miguel Ojeda <ojeda@kernel.org>
>
> Thanks Masahiro for the simplification!
>
> Cheers,
> Miguel

On Fri, Sep 13, 2024 at 8:06 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> If RUST_LIB_SRC is defined in the top-level Makefile (via an environment
> variable or command line), it is already exported.
>
> The only situation where it is defined but not exported is when the
> top-level Makefile is wrapped by another Makefile (e.g., GNUmakefile).
> I cannot think of any other use cases.
>
> I know some people use this tip to define custom variables. However,
> even in that case, you can export it directly in the wrapper Makefile.
>
> Example GNUmakefile:
>
>     export RUST_LIB_SRC = /path/to/your/sysroot/lib/rustlib/src/rust/library
>     include Makefile
>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Reviewed-by: Alice Ryhl <aliceryhl@google.com>

On Sat, Sep 14, 2024 at 03:06:20AM +0900, Masahiro Yamada wrote:
> If RUST_LIB_SRC is defined in the top-level Makefile (via an environment
> variable or command line), it is already exported.
> 
> The only situation where it is defined but not exported is when the
> top-level Makefile is wrapped by another Makefile (e.g., GNUmakefile).
> I cannot think of any other use cases.
> 
> I know some people use this tip to define custom variables. However,
> even in that case, you can export it directly in the wrapper Makefile.
> 
> Example GNUmakefile:
> 
>     export RUST_LIB_SRC = /path/to/your/sysroot/lib/rustlib/src/rust/library
>     include Makefile
> 
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> ---
> This code was added by this commit:
> 
>   https://github.com/Rust-for-Linux/linux/commit/3f46885dc03ed2d750085b2237078a1628323964
> 
> Please me know if I am missing something.

Looks good to me.

Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>