diff --git a/src/librustc_error_codes/error_codes/E0749.md b/src/librustc_error_codes/error_codes/E0749.md
index 7a1a745b53c12..dfe90ae89e4cb 100644
--- a/src/librustc_error_codes/error_codes/E0749.md
+++ b/src/librustc_error_codes/error_codes/E0749.md
@@ -11,9 +11,19 @@ trait MyTrait {
 impl !MyTrait for u32 {
     type Foo = i32; // error!
 }
-# fn main() {}
 ```
 
 Negative impls are not allowed to have any items. Negative impls declare that a
 trait is **not** implemented (and never will be) and hence there is no need to
 specify the values for trait methods or other items.
+
+One way to fix this is to remove the items in negative impls:
+
+```
+# #![feature(negative_impls)]
+trait MyTrait {
+    type Foo;
+}
+
+impl !MyTrait for u32 {}
+```