1error[E0277]: `proc_macro::Span` cannot be sent between threads safely 2 --> test-not-send.rs:5:21 3 | 45 | requires_send::<Span>(); 5 | ^^^^ `proc_macro::Span` cannot be sent between threads safely 6 | 7 = help: within `Span`, the trait `Send` is not implemented for `proc_macro::Span` 8 = note: required because it appears within the type `Span` 9 = note: required because it appears within the type `Span` 10note: required by a bound in `requires_send` 11 --> test-not-send.rs:4:25 12 | 134 | fn requires_send<T: Send>() {} 14 | ^^^^ required by this bound in `requires_send` 15 16error[E0277]: `Rc<()>` cannot be sent between threads safely 17 --> test-not-send.rs:5:21 18 | 195 | requires_send::<Span>(); 20 | ^^^^ `Rc<()>` cannot be sent between threads safely 21 | 22 = help: within `Span`, the trait `Send` is not implemented for `Rc<()>` 23 = note: required because it appears within the type `ProcMacroAutoTraits` 24 = note: required because it appears within the type `PhantomData<ProcMacroAutoTraits>` 25 = note: required because it appears within the type `Span` 26note: required by a bound in `requires_send` 27 --> test-not-send.rs:4:25 28 | 294 | fn requires_send<T: Send>() {} 30 | ^^^^ required by this bound in `requires_send` 31