While copying the build system, do_populate_sdk walks each layer and copies files over to the SDK. This brings all the ".git" folders with it. When you run oe-publish-sdk, you create a git repo at the base of those layers. Cloning that repo (when running devtool sdk-update for example) will fail to clone those layers with git repos in them. We should probably do something like: 1. Not copy git metadata when creating our SDK. 2. Remove those files when we run oe-publish-sdk.
Fixed in oe-core 6a5e2b2196e5654fc54ba5b2e51a390c966fd1b7.