尝试在我从GitHub克隆的Raspberry Pi 3上构建libreswan。一切进展顺利，直到：
/home/pi/libreswan/OBJ.linux.arm/lib/libswan/libswan.a(ike_alg.o):(.data.rel+0x2c): undefined reference to `oakley_group_dh31'
/home/pi/libreswan/OBJ.linux.arm/lib/libswan/libswan.a(ike_info.o):(.data.rel+0x44): undefined reference to `oakley_group_dh31'
collect2: error: ld returned 1 exit status
../../mk/program.mk:120: recipe for target 'pluto' failed
make[3]: *** [pluto] Error 1
../../mk/targets.mk:69: recipe for target 'base' failed
make[2]: *** [base] Error 2
make[2]: Leaving directory '/home/pi/libreswan/programs/pluto'
../mk/targets.mk:69: recipe for target 'recursive-base' failed
make[1]: *** [recursive-base] Error 2
make[1]: Leaving directory '/home/pi/libreswan/programs'
mk/targets.mk:69: recipe for target 'recursive-base' failed
make: *** [recursive-base] Error 2
（./ mk / userland-cflags.mk中）似乎存在问题：
USE_DH31 ?= true
ifeq ($(USE_DH31),true)
USERLAND_CFLAGS += -DUSE_DH31
endif
有人遇到过这个问题吗？我不想破解解决方案吗？