--- /dev/null
+error[E0308]: mismatched types
+ --> $DIR/sugar.rs:12:7
+ |
+LL | a(x);
+ | ^ expected trait `Foo + Send`, found trait `Foo + Sync`
+ |
+ = note: expected struct `Box<(dyn Foo + Send + 'static)>`
+ found struct `Box<(dyn Foo + Sync + 'static)>`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.