2018-01-02 2:24 GMT+01:00 Gershom B <gershomb@gmail.com>:

A recent update to hackage, which fixed up the 01-index.tar.gz file,
revealed a bug in existing versions of cabal-install, when index files
are cleaned up. This bug means that the `cabal update` command, which
updates the hackage index file, will fail silently and leave the old
file in place. It is easy to get things working again, but it requires
manual intervention. [...]

Quick question: Are stack users affected, too, or only cabal users? I'm just asking because as a stack user you have ~/.stack/indices/Hackage/01-index.* files lying around, too...