ghc/packages/Cabal is not a valid repository name

On 2016-11-05 I was able to follow the newcomer build instructions https://ghc.haskell.org/trac/ghc/wiki/Newcomers and built ghc on Windows with MSYS2 x64. I am now repeating those steps and see that doing a clean recursive clone of ghc fails for the Cabal submodule and many others ...

$ git clone --recursive git://github.com/ghc/ghc

Cloning into '/d/Dev/Src/ghc/libraries/Cabal'...
fatal: remote error:
  ghc/packages/Cabal is not a valid repository name

I tried the exact same recursive clone on OSX and it completed without error.

Edited Mar 10, 2019 by Phil de Joux

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information