Probe that toolchain to install ghc exists

Judging from social media, it seems people routinely ignore a warning to install build-essential libffi-dev libffi7 libgmp-dev libgmp10 libncurses-dev libncurses5 libtinfo5. While it's difficult to probe for libraries in a cross-platform way, could ghcup probe that build-essential tools are in PATH? This might help in a typical case.