Re: [PATCH v2 12/48] kcsan: clang: retire CONFIG_KCSAN_KCOV_BROKEN

[Marco Elver]

On Tue, 29 Mar 2022 at 14:41, Alexander Potapenko <glider@xxxxxxxxxx> wrote:
>
> kcov used to be broken prior to Clang 11, but right now that version is
> already the minimum required to build with KCSAN, because no prior
> compiler has "-tsan-distinguish-volatile=1".
>
> Therefore KCSAN_KCOV_BROKEN is not needed anymore.
>
> Suggested-by: Marco Elver <elver@xxxxxxxxxx>
> Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>

FYI, this is superseded by
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b027471adaf955efde6153d67f391fe1604b7292

> ---
> Link: https://linux-review.googlesource.com/id/Ida287421577f37de337139b5b5b9e977e4a6fee2
> ---
>  lib/Kconfig.kcsan | 11 -----------
>  1 file changed, 11 deletions(-)
>
> diff --git a/lib/Kconfig.kcsan b/lib/Kconfig.kcsan
> index 63b70b8c55519..de022445fbba5 100644
> --- a/lib/Kconfig.kcsan
> +++ b/lib/Kconfig.kcsan
> @@ -10,21 +10,10 @@ config HAVE_KCSAN_COMPILER
>           For the list of compilers that support KCSAN, please see
>           <file:Documentation/dev-tools/kcsan.rst>.
>
> -config KCSAN_KCOV_BROKEN
> -       def_bool KCOV && CC_HAS_SANCOV_TRACE_PC
> -       depends on CC_IS_CLANG
> -       depends on !$(cc-option,-Werror=unused-command-line-argument -fsanitize=thread -fsanitize-coverage=trace-pc)
> -       help
> -         Some versions of clang support either KCSAN and KCOV but not the
> -         combination of the two.
> -         See https://bugs.llvm.org/show_bug.cgi?id=45831 for the status
> -         in newer releases.
> -
>  menuconfig KCSAN
>         bool "KCSAN: dynamic data race detector"
>         depends on HAVE_ARCH_KCSAN && HAVE_KCSAN_COMPILER
>         depends on DEBUG_KERNEL && !KASAN
> -       depends on !KCSAN_KCOV_BROKEN
>         select STACKTRACE
>         help
>           The Kernel Concurrency Sanitizer (KCSAN) is a dynamic
> --
> 2.35.1.1021.g381101b075-goog
>