patch

sed -i 's/-O2/-Og/g' Makefile

Disable BUILD_BUG_ON easy! :)

git diff include/asm-generic/fixmap.h

diff --git a/include/asm-generic/fixmap.h b/include/asm-generic/fixmap.h
index 8cc7b09c1bc7..f6588d25e9fa 100644
--- a/include/asm-generic/fixmap.h
+++ b/include/asm-generic/fixmap.h
@@ -29,7 +29,7 @@
  */
 static __always_inline unsigned long fix_to_virt(const unsigned int idx)
 {
-       BUILD_BUG_ON(idx >= __end_of_fixed_addresses);
+       BUILD_BUG_ON(false && idx >= __end_of_fixed_addresses);
        return __fix_to_virt(idx);
 }

git diff include/linux/thread_info.h

diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index 0999f6317978..bb6f799422ea 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -204,7 +204,7 @@ static __always_inline __must_check bool
 check_copy_size(const void *addr, size_t bytes, bool is_source)
 {
        int sz = __compiletime_object_size(addr);
-       if (unlikely(sz >= 0 && sz < bytes)) {
+       if (false && unlikely(sz >= 0 && sz < bytes)) {
                if (!__builtin_constant_p(bytes))
                        copy_overflow(sz, bytes);
                else if (is_source)

build

make defconfig
make -j8
build with arm64 default config

qemu aarch64

qemu-system-aarch64 -S \
-machine virt -cpu cortex-a72 -machine type=virt -machine gic_version=3 -nographic \
-smp 4 -m 4096 \
-kernel arch/arm64/boot/Image \
--append "console=ttyAMA0 nokaslr" -s

gdb-multiarch

gdb-multiarch
setup arch aarch64
target remote:1234
file vmlinux