Re: [PATCH] lib/Kconfig.debug: Require a release version of LLVM 22 for context analysis

[Marco Elver]

On Wed, 25 Feb 2026 at 00:16, Nathan Chancellor <nathan@xxxxxxxxxx> wrote:
>
> Using a prerelease version as a minimum supported version for
> CONFIG_WARN_CONTEXT_ANALYSIS was reasonable to do while LLVM 22 was the
> development version so that people could immediately build from main and
> start testing and validating this in their own code. However, it can be
> problematic when using prerelease versions of LLVM 22, such as Android
> clang 22.0.1 (the current android mainline compiler) or when bisecting
> LLVM between llvmorg-22-init and llvmorg-23-init, to build the kernel,
> as all compiler fixes for the context analysis may not be present,
> potentially resulting in warnings that can easily turn into errors.
>
> Now that LLVM 22 is released as 22.1.0, upgrade the check to require at
> least this version to ensure that a user's toolchain actually has all
> the changes needed for a smooth experience with context analysis.
>
> Fixes: 3269701cb256 ("compiler-context-analysis: Add infrastructure for Context Analysis with Clang")
> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>

Acked-by: Marco Elver <elver@xxxxxxxxxx>

> ---
> Peter, could you take this for a 7.0-rc?
> ---
>  lib/Kconfig.debug | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 4e2dfbbd3d78..8e2b858078e6 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -630,7 +630,7 @@ config DEBUG_FORCE_WEAK_PER_CPU
>
>  config WARN_CONTEXT_ANALYSIS
>         bool "Compiler context-analysis warnings"
> -       depends on CC_IS_CLANG && CLANG_VERSION >= 220000
> +       depends on CC_IS_CLANG && CLANG_VERSION >= 220100
>         # Branch profiling re-defines "if", which messes with the compiler's
>         # ability to analyze __cond_acquires(..), resulting in false positives.
>         depends on !TRACE_BRANCH_PROFILING
> @@ -641,7 +641,7 @@ config WARN_CONTEXT_ANALYSIS
>           and releasing user-definable "context locks".
>
>           Clang's name of the feature is "Thread Safety Analysis". Requires
> -         Clang 22 or later.
> +         Clang 22.1.0 or later.
>
>           Produces warnings by default. Select CONFIG_WERROR if you wish to
>           turn these warnings into errors.
>
> ---
> base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
> change-id: 20260224-bump-clang-ver-context-analysis-b4f5e27d208e
>
> Best regards,
> --
> Nathan Chancellor <nathan@xxxxxxxxxx>
>