Comment #3 on issue 795 by kimgr: IWYU crashes with assertion failure `Name is not a simple identifier`
I've played around with this a little off and on, and I can confirm that it's crashing on the lambda expression, because it's unnamed.
While that's easy to fix, e.g. by checking if the `FunctionDecl` lacks an identifier, doing so turns into a really strange suggestion to add a forward decl for `union f::::::X`. So I think it would make sense to try and fix the root cause -- we should not suggest a forward declaration in this case.
But maybe it's better to make sure we don't crash, so the analysis is a little wrong, but at least not entirely broken.