core-y += arch/um/sys-x86_64/
START := 0x60000000
+_extra_flags_ = -fno-builtin -m64 -mcmodel=kernel
+
#We #undef __x86_64__ for kernelspace, not for userspace where
#it's needed for headers to work!
-CFLAGS += -U__$(SUBARCH)__ -fno-builtin -m64
-USER_CFLAGS += -fno-builtin -m64
+CFLAGS += -U__$(SUBARCH)__ $(_extra_flags_)
+USER_CFLAGS += $(_extra_flags_)
+
CHECKFLAGS += -m64
AFLAGS += -m64
LDFLAGS += -m elf_x86_64
+CPPFLAGS += -m64
ELF_ARCH := i386:x86-64
ELF_FORMAT := elf64-x86-64