depends on ARCH_SUPPORTS_CFI_CLANG
depends on $(cc-option,-fsanitize=kcfi)
help
- This option enables Clang’s forward-edge Control Flow Integrity
+ This option enables Clang's forward-edge Control Flow Integrity
(CFI) checking, where the compiler injects a runtime check to each
indirect function call to ensure the target is a valid function with
the correct static type. This restricts possible call targets and
default 4 if FUNCTION_ALIGNMENT_4B
default 0
+config CC_HAS_MIN_FUNCTION_ALIGNMENT
+ # Detect availability of the GCC option -fmin-function-alignment which
+ # guarantees minimal alignment for all functions, unlike
+ # -falign-functions which the compiler ignores for cold functions.
+ def_bool $(cc-option, -fmin-function-alignment=8)
+
+config CC_HAS_SANE_FUNCTION_ALIGNMENT
+ # Set if the guaranteed alignment with -fmin-function-alignment is
+ # available or extra care is required in the kernel. Clang provides
+ # strict alignment always, even with -falign-functions.
+ def_bool CC_HAS_MIN_FUNCTION_ALIGNMENT || CC_IS_CLANG
+
endmenu