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diff --git a/src/librustc_error_codes/error_codes/E0657.md b/src/librustc_error_codes/error_codes/E0657.md
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+A lifetime bound on a trait implementation was captured at an incorrect place.
+
+Erroneous code example:
+
+```compile_fail,E0657
+trait Id<T> {}
+trait Lt<'a> {}
+
+impl<'a> Lt<'a> for () {}
+impl<T> Id<T> for T {}
+
+fn free_fn_capture_hrtb_in_impl_trait()
+    -> Box<for<'a> Id<impl Lt<'a>>> // error!
+{
+    Box::new(())
+}
+
+struct Foo;
+impl Foo {
+    fn impl_fn_capture_hrtb_in_impl_trait()
+        -> Box<for<'a> Id<impl Lt<'a>>> // error!
+    {
+        Box::new(())
+    }
+}
+```
+
+Here, you have used the inappropriate lifetime in the `impl Trait`,
+The `impl Trait` can only capture lifetimes bound at the fn or impl
+level.
+
+To fix this we have to define the lifetime at the function or impl
+level and use that lifetime in the `impl Trait`. For example you can
+define the lifetime at the function:
+
+```
+trait Id<T> {}
+trait Lt<'a> {}
+
+impl<'a> Lt<'a> for () {}
+impl<T> Id<T> for T {}
+
+fn free_fn_capture_hrtb_in_impl_trait<'b>()
+    -> Box<for<'a> Id<impl Lt<'b>>> // ok!
+{
+    Box::new(())
+}
+
+struct Foo;
+impl Foo {
+    fn impl_fn_capture_hrtb_in_impl_trait<'b>()
+        -> Box<for<'a> Id<impl Lt<'b>>> // ok!
+    {
+        Box::new(())
+    }
+}
+```