Hi, 

Due to Daniel Schaefer's suggestion, I describe my case in details.

My case reproduction steps:

ENV:

Host: Ubuntu 20.04 but local $LANG is zh_CN.utf8

VM: Fedora RISCV Kernel 5.5 and local $LANG is en_US.UTF-8

Steps: 

1) Boot up Fedora RISCV VM:

qemu-system-riscv64 \
>   -nographic \
>   -machine virt \
>   -smp 8 \
>   -m 2G \
>   -kernel Fedora-Developer-Rawhide-20200108.n.0-fw_payload-uboot-qemu-virt-smode.elf \
>   -object rng-random,filename=/dev/urandom,id=rng0 \
>   -device virtio-rng-device,rng=rng0 \
>   -device virtio-blk-device,drive=hd0 \
>   -drive file=Fedora-Developer-Rawhide-20200108.n.0-sda.raw,format=raw,id=hd0 \
>   -device virtio-net-device,netdev=usernet \
>   -netdev user,id=usernet,hostfwd=tcp::10000-:22

2) SSH to Fedora RISCV VM from Host:

ssh -p 10000 -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o PreferredAuthentications=password -o PubkeyAuthentication=no root@localhost

3) Login Fedora RISCV VM: 

Inherit Host env variable $LANG "zh_CN.utf8", although the VM's local $LANG var in /etc/locale.conf is "en_US.UTF-8".

4) Build the EDK2 binary:
build -a RISCV64 -t GCC5 -p Platform/SiFive/U5SeriesPkg/FreedomU540HiFiveUnleashedBoard/U540.dsc

When building, UiApp.offset file not created is due to the offset variable cannot be fetched from UiApp.map file, and it causes the building failed.

The root cause of UiApp.offset file not created is "Archive member included" does not appears in the head of UiApp.map.

But instead, "Archive member included" is written in Chinese words in UiApp.map in my case. So offset var cannot be fetched because GetVariableOffset doesn't handle Chinese words in its code logic.

So it's probably edk2 prioritizes or only handles env var $LANG, but not check $LANG difference between env var and /etc/locale.conf.

My case workaround: Just re-source the VM local "/etc/locale.conf" to change the $LANG to "en_US.UTF-8" and re-build the binary, then succeed.

Best Regards