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This patch changes CONFIG_CFI_CLANG to depend on the built-in and effectively upgrades the minimum supported compiler version for CFI to Clang 14. Signed-off-by: Sami Tolvanen --- arch/Kconfig | 5 +---- init/Kconfig | 3 +++ 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 29b0167c088b..eecfc2809781 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -723,10 +723,7 @@ config ARCH_SUPPORTS_CFI_CLANG config CFI_CLANG bool "Use Clang's Control Flow Integrity (CFI)" depends on LTO_CLANG && ARCH_SUPPORTS_CFI_CLANG - # Clang >=3D 12: - # - https://bugs.llvm.org/show_bug.cgi?id=3D46258 - # - https://bugs.llvm.org/show_bug.cgi?id=3D47479 - depends on CLANG_VERSION >=3D 120000 + depends on CC_HAS_BUILTIN_FUNCTION_START select KALLSYMS help This option enables Clang=E2=80=99s forward-edge Control Flow Integrity diff --git a/init/Kconfig b/init/Kconfig index ddcbefe535e9..f024fd353373 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -86,6 +86,9 @@ config CC_HAS_ASM_INLINE config CC_HAS_NO_PROFILE_FN_ATTR def_bool $(success,echo '__attribute__((no_profile_instrument_function)) = int x();' | $(CC) -x c - -c -o /dev/null -Werror) =20 +config CC_HAS_BUILTIN_FUNCTION_START + def_bool $(success,echo 'void f(void) {}; 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