編譯OmniROM 8.1時，在這個地方出錯：
[ 21% 2441/11398] //external/selinux/checkpolicy:checkpolicy lex policy_scan.l [linux]
FAILED: /home/anclark/Wonderland/aosp3/omni8/out/soong/.intermediates/external/selinux/checkpolicy/checkpolicy/linux_x86_64/gen/lex/external/selinux/checkpolicy/policy_scan.c
prebuilts/misc/linux-x86/flex/flex-2.5.39 -o/home/anclark/Wonderland/aosp3/omni8/out/soong/.intermediates/external/selinux/checkpolicy/checkpolicy/linux_x86_64/gen/lex/external/selinux/checkpolicy/policy_scan.c external/selinux/checkpolicy/policy_scan.l
flex-2.5.39: loadlocale.c:130: _nl_intern_locale_data: Assertion `cnt < (sizeof (_nl_value_type_LC_TIME) / sizeof (_nl_value_type_LC_TIME[0]))' failed.
Aborted (core dumped)
其中涉及到了Flex這款語法解釋器生成器（lexical analyser generator），它的作用是將以*.l爲擴展名的源文件編譯成解釋器的C語言代碼。checkpolicy這個用於檢測SELinux策略（SELinux policy）的工具，正是使用flex來解析策略文件的語法的。
Android Ninja編譯系統的好處是，會將出錯的命令記錄在屏幕上。拷貝上述出錯的命令，重新執行：
prebuilts/misc/linux-x86/flex/flex-2.5.39 -o/home/anclark/Wonderland/aosp3/omni8/out/soong/.intermediates/external/selinux/checkpolicy/checkpolicy/linux_x86_64/gen/lex/external/selinux/checkpolicy/policy_scan.c external/selinux/checkpolicy/policy_scan.l
發現問題依舊。
於是，筆者試着更換一個Flex版本，以apt安裝的版本2.6.4（sudo apt install flex）嘗試編譯：
flex -o/home/anclark/Wonderland/aosp3/omni8/out/soong/.intermediates/external/selinux/checkpolicy/checkpolicy/linux_x86_64/gen/lex/external/selinux/checkpolicy/policy_scan.c external/selinux/checkpolicy/policy_scan.l
結果成功！
看來，問題就出在OmniROM源碼附帶的Flex2.5.39版本里。
暫時使用符號鏈接，將OmniROM自帶的Flex更換爲apt的最新版：
ln -s /usr/bin/flex prebuilts/misc/linux-x86/flex/flex-2.5.39