1 files changed, 20 insertions, 0 deletions
diff --git a/compiler/rustc_error_codes/src/error_codes/E0276.md b/compiler/rustc_error_codes/src/error_codes/E0276.md
new file mode 100644
index 000000000..ad76968c5
--- /dev/null
+++ b/compiler/rustc_error_codes/src/error_codes/E0276.md
@@ -0,0 +1,20 @@
+A trait implementation has stricter requirements than the trait definition.
+
+Erroneous code example:
+
+```compile_fail,E0276
+trait Foo {
+    fn foo<T>(x: T);
+}
+
+impl Foo for bool {
+    fn foo<T>(x: T) where T: Copy {}
+}
+```
+
+Here, all types implementing `Foo` must have a method `foo<T>(x: T)` which can
+take any type `T`. However, in the `impl` for `bool`, we have added an extra
+bound that `T` is `Copy`, which isn't compatible with the original trait.
+
+Consider removing the bound from the method or adding the bound to the original
+method definition in the trait.