[RFC PATCH v2 00/13] objtool: add base support for arm64

[Nick Desaulniers]

(in response to
https://lore.kernel.org/linux-arm-kernel/20210303170932.1838634-1-jthierry@redhat.com/
from the command line)

> Changes since v1[2]:
> - Drop gcc plugin in favor of -fno-jump-tables

Thank you for this!  I built+booted(under emulation) arm64 defconfig and built
arm64 allmodconfig with LLVM=1 with this series applied.

Tested-by: Nick Desaulniers <ndesaulniers at google.com>

One thing I noticed was a spew of warnings for allmodconfig, like:
init/main.o: warning: objtool: asan.module_ctor()+0xc: call without frame pointer save/setup
init/main.o: warning: objtool: asan.module_dtor()+0xc: call without frame pointer save/setup

I assume those are from the KASAN constructors. See also:
https://github.com/ClangBuiltLinux/linux/issues/1238

Can we disable HAVE_STACK_PROTECTOR if CC_IS_CLANG and CONFIG_KASAN is set,
until we can resolve the above issue?