compiling clang on ubuntu 20.04, the link step used up all my ram and started swapping on the nvme. htop froze, so i hit ctrl-c, but nothing happened. no mouse

compiling clang on ubuntu 20.04, the link step used up all my ram and started swapping on the nvme. htop froze, so i hit ctrl-c, but nothing happened. no mouse movement, no ssh'ing in, just totally hard-locked. i ended up having to physically powercycle the machine. after that i turned off swap so that it killed the process rather than the machine (and remembered to pass -DLLVM_PARALLEL_LINK_JOBS=1)