I found it's quite painful. There seems no global target for cleaning up everything and do a rebuild. (e.g. if you rename your directories, things will break; and you want to do a clean build).
The best approach I found is to clean up individual targets. Go to build/. Then type make <tab>. It will list all targets. Execute targets end with -clean. e.g. make optee-os-clean
mv edk2/Conf/BuildEnv.sh /tmp
Explanation: edk2 seems to be in particular problematic. It's build environment, edk2/Conf/BuildEnv.sh, always contains stale configurations. Symptoms: make edk2 cannot find build command; make edk2-clean fails, etc.
- Just manually rename or remove it, then do a clean build of edk2.
Go to the top directory
mkdir -p edk2-platforms
Explanation: to make ``make edk2-clean'' happy.
cd trusted-firmware-a
make clean
Explanation: arm-tf can be problematic. do make arm-tf-clean under build does not clean tools like tools/fiptool/fiptool, which may link to libs that have stale paths (e.g. tools/fiptool/fiptool: error while loading shared libraries: libcrypto.so.3: cannot open shared...)
Then go to build/, do make clean. It should finish without any errors.