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+A trait type has been dereferenced.
+
+Erroneous code example:
+
+```compile_fail,E0033
+# trait SomeTrait { fn method_one(&self){} fn method_two(&self){} }
+# impl<T> SomeTrait for T {}
+let trait_obj: &SomeTrait = &"some_value";
+
+// This tries to implicitly dereference to create an unsized local variable.
+let &invalid = trait_obj;
+
+// You can call methods without binding to the value being pointed at.
+trait_obj.method_one();
+trait_obj.method_two();
+```
+
+A pointer to a trait type cannot be implicitly dereferenced by a pattern. Every
+trait defines a type, but because the size of trait implementers isn't fixed,
+this type has no compile-time size. Therefore, all accesses to trait types must
+be through pointers. If you encounter this error you should try to avoid
+dereferencing the pointer.
+
+You can read more about trait objects in the [Trait Objects] section of the
+Reference.
+
+[Trait Objects]: https://doc.rust-lang.org/reference/types.html#trait-objects