performed --bless of 15 ui tests affected

1 files changed, 50 insertions, 19 deletions

diff --git a/src/librustc_error_codes/error_codes/E0637.md b/src/librustc_error_codes/error_codes/E0637.md
index 978cf273c94..ba81e42ce08 100644
--- a/src/librustc_error_codes/error_codes/E0637.md
+++ b/src/librustc_error_codes/error_codes/E0637.md
@@ -1,31 +1,62 @@
-An underscore `_` character or a numeric literal `u8`, `i32`, `f64`, etc has
-been used as the identifier for a lifetime.
+An underscore `_` character has been used as the identifier for a lifetime,
+or a const generic has been borrowed without an explicit lifetime.
 
-Erroneous code example 1:
+Erroneous example with an underscore:
 ```
-fn some_function<'_>(str1: &'_ str, str2: &'_ str) -> &'_ str {
-    //Some code
-}
+fn foo<'_>(str1: &'_ str, str2: &'_ str) -> &'_ str {}
+    // ^^ `'_` is a reserved lifetime name
+```
+Lifetimes are named with `'ident`, where ident is the name of the lifetime or
+loop. The `_` character, which represents the ignore pattern, cannot be used
+as the identifier because it is a reserved lifetime name. To fix
+this, use a lowercase letter, or a series of lowercase letters as the lifetime
+identifier. Often a single lowercase letter, such as `'a`, is sufficient.  For
+more information, see
+[the book][bk-no].
+
+Corrected underscore example:
+```
+fn <'a>(str1: &'a str, str2: &'a str) -> &'a str {}
 ```
-or Erroneous code example 2:
+
+Erroneous example with const generic:
 ```
-fn some_function<'u8>(str1: &'u8 str, str2: &'u8 str) -> &'u8 str {
-    //Some code
+struct A<const N: &u8>;
+//~^ ERROR `&` without an explicit lifetime name cannot be used here
+trait B {}
+
+impl<const N: &u8> A<N> { 
+//~^ ERROR `&` without an explicit lifetime name cannot be used here
+    fn foo<const M: &u8>(&self) {}
+    //~^ ERROR `&` without an explicit lifetime name cannot be used here
+}
+
+impl<const N: &u8> B for A<N> {}
+//~^ ERROR `&` without an explicit lifetime name cannot be used here
+
+fn bar<const N: &u8>() {}
+//~^ ERROR `&` without an explicit lifetime name cannot be used here
 }
 ```
 
-Lifetimes are named with `'ident`, where ident is the name of the lifetime or
-loop. The `_` character, which represents the ignore pattern, cannot be used
-as the identifier because it is a reserved lifetime name. Numeric literals are
-also invalid lifetime identifiers and will cause this error to be thrown. To fix
-this, use a series of lowercase letters as the lifetime identifier. Often a
-single lowercase letter, such as `'a`, is sufficient.  For more information, see
-[the book][bk-no].
+Const generics cannot be borrowed without specifying a lifetime.The 
+compiler handles memory allocation of constants differently than that of
+variables and it cannot infer the lifetime of the borrowed constant.
+To fix this, explicitly specify a lifetime for the const generic.
 
-Corrected code example:
+Corrected const generic example:
 ```
-fn some_function<'a>(str1: &'a str, str2: &'a str) -> &'a str {
-    //Some code
+struct A<const N: &'a u8>;
+
+trait B {}
+
+impl<const N: &'a u8> A<N> {
+    fn foo<const M: &'a u8>(&self) {}
+}
+
+impl<const N: &'a u8> B for A<N> {}
+
+fn bar<const N: &'a u8>() {}
 }
 ```
 [bk-no]: https://doc.rust-lang.org/book/appendix-02-operators.html#non-operator-symbols