error[E0751]: found both positive and negative implementation of trait `Send` for type `TestType<_>`: --> $DIR/coherence-conflicting-negative-trait-impl.rs:11:1 | LL | unsafe impl Send for TestType {} | ------------------------------------------------------ positive implementation here LL | LL | impl !Send for TestType {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ negative implementation here error[E0119]: conflicting implementations of trait `Send` for type `TestType<_>` --> $DIR/coherence-conflicting-negative-trait-impl.rs:13:1 | LL | unsafe impl Send for TestType {} | ------------------------------------------------------ first implementation here ... LL | unsafe impl Send for TestType {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `TestType<_>` error: aborting due to 2 previous errors Some errors have detailed explanations: E0119, E0751. For more information about an error, try `rustc --explain E0119`.