ps2: Now even after I remove'd libclang-dev, theide in upp version 16443 won't work. You don't even need to type in anything, it will crash itself with invalid memory access in just a few seconds(when background parsing threads start). It looks like a libclang version problem. For now, I will go back to upp version 16303 on which autocomplete works fine.

sudo bash -c "$(wget -O - https://apt.llvm.org/llvm.sh)"