comment out record of now-unused error code E0563

The sole appearance of this code was deleted in 6383de15; the existing practice
in these cases seems to be to comment out its mention in
`register_diagnostics!`.

diff --git a/src/librustc_typeck/diagnostics.rs b/src/librustc_typeck/diagnostics.rs
index 3037e8d4a16022fda56d28d647e9422169cbc5c0..1323997315e78a32e8522a2540bbb7441ff921b4 100644 (file)
--- a/src/librustc_typeck/diagnostics.rs
+++ b/src/librustc_typeck/diagnostics.rs
@@ -4709,7 +4709,7 @@ fn i_am_a_function() {}
            // between structures with the same definition
     E0521, // redundant default implementations of trait
     E0533, // `{}` does not name a unit variant, unit struct or a constant
-    E0563, // cannot determine a type for this `impl Trait`: {}
+//  E0563, // cannot determine a type for this `impl Trait`: {} // removed in 6383de15
     E0564, // only named lifetimes are allowed in `impl Trait`,
            // but `{}` was found in the type `{}`
     E0567, // auto traits can not have type parameters