Re: [PATCH v2] rust: enable slice_flatten feature and provide it through an extension trait

[Alexandre Courbot]

On Tue Nov 4, 2025 at 11:10 PM JST, Alice Ryhl wrote:
>> diff --git a/scripts/Makefile.build b/scripts/Makefile.build
>> index d0ee33a487be..a84b9e3171a3 100644
>> --- a/scripts/Makefile.build
>> +++ b/scripts/Makefile.build
>> @@ -308,6 +308,7 @@ $(obj)/%.lst: $(obj)/%.c FORCE
>>  
>>  # The features in this list are the ones allowed for non-`rust/` code.
>>  #
>> +#   - Stable since Rust 1.80.0: `feature(slice_flatten)`.
>>  #   - Stable since Rust 1.81.0: `feature(lint_reasons)`.
>>  #   - Stable since Rust 1.82.0: `feature(asm_const)`,
>>  #     `feature(offset_of_nested)`, `feature(raw_ref_op)`.
>> @@ -317,7 +318,7 @@ $(obj)/%.lst: $(obj)/%.c FORCE
>>  #
>>  # Please see https://github.com/Rust-for-Linux/linux/issues/2 for details on
>>  # the unstable features in use.
>> -rust_allowed_features := asm_const,asm_goto,arbitrary_self_types,lint_reasons,offset_of_nested,raw_ref_op,used_with_arg
>> +rust_allowed_features := asm_const,asm_goto,arbitrary_self_types,lint_reasons,offset_of_nested,raw_ref_op,slice_flatten,used_with_arg
>
> You should double-check, but I don't think you need to list it here
> because all uses of the unstable method are under the `rust/` directory.

Confirmed that this is not needed, thank you!