iPXE EFI build fails with PXE_STACK defined

Code:
[AR] bin-x86_64-efi/blib.a

ar: creating bin-x86_64-efi/blib.a

  [HOSTCC] util/elf2efi64

  [VERSION] bin-x86_64-efi/version.ipxe.efi.o

  [LD] bin-x86_64-efi/ipxe.efi.tmp

bin-x86_64-efi/blib.a(librm.o): In function `pm_esp':

(.data.pm_esp+0x0): relocation truncated to fit: R_X86_64_32 against symbol `_estack' defined in .stack section in bin-x86_64-efi/blib.a(stack.o)

bin-x86_64-efi/blib.a(librm.o): In function `real_to_prot':

(.text16.real_to_prot+0x1): relocation truncated to fit: R_X86_64_PC16 against symbol `enable_a20' defined in .text16.early section in bin-x86_64-efi/blib.a(liba20.o)

bin-x86_64-efi/blib.a(librm.o): In function `real_to_prot':

(.text16.real_to_prot+0x8): relocation truncated to fit: R_X86_64_16 against symbol `rm_ds' defined in .text16.data.rm_ds section in bin-x86_64-efi/blib.a(librm.o)

bin-x86_64-efi/blib.a(librm.o): In function `real_to_prot':

(.text16.real_to_prot+0x25): relocation truncated to fit: R_X86_64_16 against `.bss16.rm_virt_addrs'

bin-x86_64-efi/blib.a(librm.o): In function `real_to_prot':

(.text16.real_to_prot+0x2b): relocation truncated to fit: R_X86_64_16 against `.data16.gdt'

bin-x86_64-efi/blib.a(librm.o): In function `real_to_prot':

(.text16.real_to_prot+0x4a): relocation truncated to fit: R_X86_64_32 against `.text.real_to_prot'

bin-x86_64-efi/blib.a(librm.o): In function `r2p_pmode':

(.text.real_to_prot+0x10): relocation truncated to fit: R_X86_64_32 against `.data.pm_esp'

bin-x86_64-efi/blib.a(librm.o): In function `r2p_pmode':

(.text.real_to_prot+0x17): relocation truncated to fit: R_X86_64_32 against symbol `idtr32' defined in .data.idtr32 section in bin-x86_64-efi/blib.a(librm_mgmt.o)

bin-x86_64-efi/blib.a(librm.o): In function `r2p_pmode':

(.text.real_to_prot+0x1e): relocation truncated to fit: R_X86_64_32 against symbol `rm_ss' defined in .bss.rm_ss section in bin-x86_64-efi/blib.a(librm.o)

bin-x86_64-efi/blib.a(librm.o): In function `r2p_pmode':

(.text.real_to_prot+0x27): relocation truncated to fit: R_X86_64_32 against symbol `rm_sp' defined in .bss.rm_sp section in bin-x86_64-efi/blib.a(librm.o)

bin-x86_64-efi/blib.a(librm.o): In function `prot_to_real':

(.text.prot_to_real+0x2): additional relocation overflows omitted from the output

bin-x86_64-efi/blib.a(pxe_entry.o): In function `pxe_segments':

(.text16.data+0x26): undefined reference to `_data16_memsz'

bin-x86_64-efi/blib.a(pxe_entry.o): In function `pxe_segments':

(.text16.data+0x2e): undefined reference to `_data16_memsz'

bin-x86_64-efi/blib.a(pxe_entry.o): In function `pxe_segments':

(.text16.data+0x36): undefined reference to `_text16_memsz'

bin-x86_64-efi/blib.a(pxe_entry.o): In function `pxe_segments':

(.text16.data+0x3e): undefined reference to `_text16_memsz'

bin-x86_64-efi/blib.a(pxe_entry.o): In function `pxenv':

(.text16.data+0x76): undefined reference to `_data16_memsz'

bin-x86_64-efi/blib.a(pxe_entry.o): In function `pxenv':

(.text16.data+0x82): undefined reference to `_data16_memsz'

bin-x86_64-efi/blib.a(pxe_entry.o): In function `pxenv':

(.text16.data+0x86): undefined reference to `_text16_memsz'

Makefile.housekeeping:1104: recipe for target 'bin-x86_64-efi/ipxe.efi.tmp' failed

make: *** [bin-x86_64-efi/ipxe.efi.tmp] Error 1

rm bin-x86_64-efi/version.ipxe.efi.o