Function class_doc_conflicts 

fn class_doc_conflicts(
    definer: &ClassBlockEntry,
    blocks: &[&ClassBlockEntry],
) -> Vec<String>

The problems the doc comments of a type’s impl blocks make for its merged roxygen block (#1776): every block’s doc tags are written, so two different @titles give the class two titles (roxygen2 silently keeps the first), and a @name or @rdname other than the defining block’s would move the class block to a page the defining block’s generated documentation was not written for.