Re: [PATCH v2 1/7] compiler-clang: add build check for clang 10.0.1

From: Sedat Dilek
Date: Tue Sep 01 2020 - 09:54:19 EST


On Tue, Sep 1, 2020 at 2:23 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote:
>
> During Plumbers 2020, we voted to just support the latest release of
> Clang for now. Add a compile time check for this.
>
> We plan to remove workarounds for older versions now, which will break
> in subtle and not so subtle ways.
>
> Link: https://github.com/ClangBuiltLinux/linux/issues/9
> Link: https://github.com/ClangBuiltLinux/linux/issues/941
> Suggested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
> Suggested-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> Suggested-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Acked-by: Marco Elver <elver@xxxxxxxxxx>
> Acked-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> Acked-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx>
> Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>

Reviewed-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
Tested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>

- Sedat -

> ---
> Changes V1 -> V2:
> * use a more informational error, as per Kees.
> * collect tags.
>
> include/linux/compiler-clang.h | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h
> index cee0c728d39a..230604e7f057 100644
> --- a/include/linux/compiler-clang.h
> +++ b/include/linux/compiler-clang.h
> @@ -3,6 +3,14 @@
> #error "Please don't include <linux/compiler-clang.h> directly, include <linux/compiler.h> instead."
> #endif
>
> +#define CLANG_VERSION (__clang_major__ * 10000 \
> + + __clang_minor__ * 100 \
> + + __clang_patchlevel__)
> +
> +#if CLANG_VERSION < 100001
> +# error Sorry, your version of Clang is too old - please use 10.0.1 or newer.
> +#endif
> +
> /* Compiler specific definitions for Clang compiler */
>
> /* same as gcc, this was present in clang-2.6 so we can assume it works
> --
> 2.28.0.402.g5ffc5be6b7-goog
>