[PATCH v2] hardening: Avoid harmless Clang option under CONFIG_INIT_STACK_ALL_ZERO

[Will Deacon]

On Tue, Sep 14, 2021 at 01:02:03PM -0700, Kees Cook wrote:
> Currently under Clang, CC_HAS_AUTO_VAR_INIT_ZERO requires an extra
> -enable flag compared to CC_HAS_AUTO_VAR_INIT_PATTERN. GCC does not,
> and will happily ignore the Clang-specific flag. However, its presence
> on the command-line is both cumbersome and confusing. Due to GCC's
> tolerant behavior, though, we can continue to use a single Kconfig
> cc-option test for the feature on both compilers, but then drop the
> Clang-specific option in the Makefile.
> 
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Cc: Masahiro Yamada <masahiroy at kernel.org>
> Cc: llvm at lists.linux.dev
> Fixes: dcb7c0b9461c ("hardening: Clarify Kconfig text for auto-var-init")
> Suggested-by: Will Deacon <will at kernel.org>
> Link: https://lore.kernel.org/lkml/20210914102837.6172-1-will@kernel.org/
> Reviewed-by: Nick Desaulniers <ndesaulniers at google.com>
> Reviewed-by: Nathan Chancellor <nathan at kernel.org>
> Signed-off-by: Kees Cook <keescook at chromium.org>
> ---
>  Makefile                   | 6 +++---
>  security/Kconfig.hardening | 5 ++++-
>  2 files changed, 7 insertions(+), 4 deletions(-)

Acked-by: Will Deacon <will at kernel.org>

Cheers for sorting this out!

Will