From: Sami Tolvanen samitolvanen@google.com
commit 2120635108b35ecad9c59c8b44f6cbdf4f98214e upstream.
We enable -Wcast-function-type globally in the kernel to warn about mismatching types in function pointer casts. Compilers currently warn only about ABI incompability with this flag, but Clang 16 will enable a stricter version of the check by default that checks for an exact type match. This will be very noisy in the kernel, so disable -Wcast-function-type-strict without W=1 until the new warnings have been addressed.
Cc: stable@vger.kernel.org Link: https://reviews.llvm.org/D134831 Link: https://github.com/ClangBuiltLinux/linux/issues/1724 Suggested-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Sami Tolvanen samitolvanen@google.com Signed-off-by: Kees Cook keescook@chromium.org Link: https://lore.kernel.org/r/20220930203310.4010564-1-samitolvanen@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- scripts/Makefile.extrawarn | 1 + 1 file changed, 1 insertion(+)
--- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -50,6 +50,7 @@ KBUILD_CFLAGS += -Wno-sign-compare KBUILD_CFLAGS += -Wno-format-zero-length KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast) KBUILD_CFLAGS += $(call cc-disable-warning, unaligned-access) +KBUILD_CFLAGS += $(call cc-disable-warning, cast-function-type-strict) endif
endif