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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Tue, 13 Jun 2023 19:16:36 +0200
Message-ID: <CANiq72mTjNzLhfhax761CPDUHj=zC6qa6i3hobMWYaCvmgBAJQ@mail.gmail.com>
Subject: Re: [PATCH v3 03/57] locking: Introduce __cleanup() based infrastructure
To:     Peter Zijlstra <peterz@infradead.org>
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On Mon, Jun 12, 2023 at 11:39=E2=80=AFAM Peter Zijlstra <peterz@infradead.o=
rg> wrote:
>
> --- a/include/linux/compiler_attributes.h
> +++ b/include/linux/compiler_attributes.h
> @@ -77,6 +77,12 @@
>  #define __attribute_const__             __attribute__((__const__))
>
>  /*
> + *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.=
html#index-cleanup-variable-attribute
> + * clang: https://clang.llvm.org/docs/AttributeReference.html#cleanup
> + */
> +#define __cleanup(func)                        __attribute__((__cleanup_=
_(func)))
> +
> +/*
>   * Optional: only supported since gcc >=3D 9
>   * Optional: not supported by clang
>   *

`cleanup` goes before `const`, but apart from that, for compiler attributes=
:

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

Thanks for bringing RAII/SBRM to the kernel!

Rust also behaves like the `__cleanup__` attribute, e.g. iterating on
a loop destroys and constructs the variables defined inside the loop.
Also breaking to an outer label/scope.

By the way, maybe some of the macros in `cleanup.h` read a bit better
applying `clang-format` to it.

Cheers,
Miguel