Inconsistent revision control

[Alan Snyder]

I have been trying to use Carbon Copy Cloner to make a copy of an active jdk repo on another macOS machine for the purpose of running tests.

The initial clone is fine.

After an incremental clone of the directory tree, I get mysterious messages like this:

Inconsistent revision control: 17-24-55/ is missing .git directory

What is this about?

Is there an easy way to fix this problem?