OS Version: R65, ToT as of 1/8.
Copied from b/71708351 to keep bug public.

Attempting to build 4.14 kernel on Eve gives me a spew like so. 
The build goes on fine though..haven't loaded the kernel yet. 

kernel/sched/rt.o: warning: objtool: __enqueue_rt_entity()+0x243: can't find call dest symbol at offset 0x142b
  AR      sound/soc/xtensa/built-in.o
  CC [M]  drivers/net/ethernet/intel/e100.o
  AR      crypto/crypto_simd.o
  CC      kernel/sched/deadline.o
drivers/of/irq.o: warning: objtool: of_irq_init()+0x19a: can't find call dest symbol at offset 0x192
  CC      drivers/media/rc/keymaps/rc-avermedia-m135a.o
drivers/iio/inkern.o: warning: objtool: iio_channel_read()+0x9f: can't find call dest symbol at offset 0xba
  CC      drivers/of/of_net.o
  AR      drivers/net/ethernet/mellanox/built-in.o
fs/ext4/ialloc.o: warning: objtool: ext4_read_inode_bitmap()+0x46e: can't find call dest symbol at offset 0xbb6
  CC      lib/strncpy_from_user.o
  CC [M]  fs/nfs/client.o
  CC      drivers/pci/pci.o
  CC [M]  net/sunrpc/auth_gss/gss_rpc_xdr.o
  AR      drivers/net/wireless/cisco/built-in.o
mm/mmu_notifier.o: warning: objtool: .text.__x86.indirect_thunk.r8+0x0: can't find call dest symbol at offset 0x9
  LD [M]  crypto/ecdh_generic.o
  AR      drivers/net/wireless/intel/built-in.o
  CC      arch/x86/kernel/fpu/regset.o
  AR      fs/kernfs/built-in.o
  CC      fs/jbd2/revoke.o
  AR      drivers/net/ethernet/intel/e1000/built-in.o
  CC [M]  drivers/net/usb/r8152.o
  CC      drivers/mmc/core/pwrseq_emmc.o
drivers/md/persistent-data/dm-btree.o: warning: objtool: insert()+0x238: can't find call dest symbol at offset 0x13ff
  AR      sound/soc/zte/built-in.o


Guenter Roeck did some digging, pasting his findings from b/71708351:
"I tried "cros_workon_make --board eve sys-kernel/chromeos-kernel-4_14" as well as "USE="kasan pcserial tty_console_ttyS0" emerge-eve chromeos-kernel-4_14" in my chroot, but I don't see the problem. Did you update your chroot recently?"

"Problem shows up after updating my chroot. This may be a side effect / result of the new compilers and Sprectre mitigation."

"Reverting commit e6e13d175846d ("cros-kernel2: Use new branch option.") from chromiumos-overlay 'fixes' the problem. It appears that code generated by the new compiler confuses objtool."