Hi, I met a CMake error, “Variable KernelArch is not set” when I tried to build a seL4 project based on the open source code of the UNSW course, Advanced Operating System, aka. AOS. The original version uses odroidc2 as the building platform, and I want to build it with the riscv gnu toolchain and simulate it on qemu-riscv-virt. Here is the repository: https://github.com/SEL4PROJ/AOS-manifest The building hierachy is as the basic build system structure, with init-build.sh, setting.cmake and CMakeLists.txt in the top level. And the top level contains kernel, tools, and project folders, in which there are CMakeLists.txt and .cmake files. Since I have no experience on cmake, I tried to compare the manifest xml between AOS project and seL4test project. I found that the major difference between them are in “init-build.sh”, “setting.cmake” and the “CMakeList.txt” in the top level. There are also some unused libraries in AOS project. I tried deleting the “set PLATFORM odroidc2” command in the setting.cmake, and added the DCROSSCOMPILER=riscv-unknown-linux-gnu, DPLATFORM=qemu-riscv-virt in the build command. But they doesn’t work. After checking the “/kernel/configs/seL4Config.cmake”, it says that the error is caused since KernelArch is left as empty string… And I want to ask whether I have set anything improperly.... I will appreciate for any help. Thank you for reading my question!