Fatal: fetch-pack: invalid index-pack output --llvm-project

Trying to install swift-language. I am running into this error. I am obviously new to Arch. Any help is appreciated.

→ Cloning llvm-project git repo…
Cloning into bare repository ‘/home/user/Downloads/swift-language/llvm-project’…
remote: Enumerating objects: 5742126, done.
remote: Counting objects: 100% (526/526), done.
remote: Compressing objects: 100% (84/84), done.
fatal: fetch-pack: invalid index-pack output.82 GiB | 579.00 KiB/s
==> ERROR: Failure while downloading llvm-project git repo
Aborting…

swift-language is in the AUR. Can you try installing that. Also see this guide arch wiki.

Not sure but probably a network related error. Similar issue on stackoverflow.