Function rustc_query_impl::make_query::object_lifetime_defaults_map

pub fn object_lifetime_defaults_map<'tcx>(
    tcx: QueryCtxt<'tcx>, 
    key: object_lifetime_defaults_map<'tcx>
) -> QueryStackFrame

For a given item (like a struct), gets the default lifetimes to be used for each parameter if a trait object were to be passed for that parameter. For example, for struct Foo<'a, T, U>, this would be ['static, 'static]. For struct Foo<'a, T: 'a, U>, this would instead be ['a, 'static].