syntax_data: {"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // The only side-effect of this is possibly worse diagnostics in case the layout
context_before:     // Types that reference `ty::Error` pessimistically don't have a meaningful layout.
context_after:     // was actually computable (like if the `ty::Error` showed up only in a `PhantomData`).