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...
Gershom sent me an email about this earlier, and I looked into it. As far as I can tell, Stack is _not_ affected by this, since—although it uses the same hackage-security library as cabal-install—it follows a different codepath outside of hackage-security for downloading tarballs. I'm not 100% certain Stack is immune, however, so if someone notices a problem, please report it.