Weirdly, initializer indentation is controlled by `ContinuationIndentWidth` rather than by `IndentWidth`. That one I would agree is a clang-format bug, or a mistaken policy decision.

I haven't myself worked on a tabbed code base during clang-format's existence. You might want to look at Linux's settings for ideas, although they clearly differ from your preferences in other ways. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin...