Ubuntu 20.10 does not have `libffi7`
Which ghcup asks to be installed. I believe the correct package for 20.10 is libffi8ubuntu1. https://packages.ubuntu.com/groovy/libffi8ubuntu1
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Which ghcup asks to be installed. I believe the correct package for 20.10 is libffi8ubuntu1. https://packages.ubuntu.com/groovy/libffi8ubuntu1