As with LLVM and most of the git world, CIRCT has migrated to use ‘main’ as the branch name. You’ll want to update your local repositories as well.
Note: the ‘master’ branch can’t be removed because of the outstanding pull requests. Please update your pull requests to the ‘main’ branch.
Can the ‘master’ branch be removed now, I don’t see any outstanding pull requests. I’ve opened a separate thread about this, as the current situation has resulted in 404s: Can the 'master' branch be deleted?