Auto merge of #141710 - tgross35:rollup-ecyw183, r=tgross35

Rollup of 8 pull requests

Successful merges:

 - #125087 (Optimize `Seek::stream_len` impl for `File`)
 - #138285 (Stabilize `repr128`)
 - #139994 (add `CStr::display`)
 - #141477 (Path::with_extension: show that it adds an extension where one did no…)
 - #141533 (clean up old rintf leftovers)
 - #141690 (Add `rustc_diagnostic_item` to `sys::Mutex` methods)
 - #141693 (Subtree update of `rust-analyzer`)
 - #141702 (Add eholk to compiler reviewer rotation)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_error_codes/src/error_codes/E0658.md

@@ -3,10 +3,7 @@ An unstable feature was used.
 Erroneous code example:
 
 ```compile_fail,E0658
-#[repr(u128)] // error: use of unstable library feature 'repr128'
-enum Foo {
-    Bar(u64),
-}
+use std::intrinsics; // error: use of unstable library feature `core_intrinsics`
 ```
 
 If you're using a stable or a beta version of rustc, you won't be able to use
@@ -17,12 +14,9 @@ If you're using a nightly version of rustc, just add the corresponding feature
 to be able to use it:
 
 ```
-#![feature(repr128)]
+#![feature(core_intrinsics)]
 
-#[repr(u128)] // ok!
-enum Foo {
-    Bar(u64),
-}
+use std::intrinsics; // ok!
 ```
 
 [rustup]: https://rust-lang.github.io/rustup/concepts/channels.html

compiler/rustc_feature/src/accepted.rs

@@ -360,6 +360,8 @@ declare_features! (
     (accepted, relaxed_adts, "1.19.0", Some(35626)),
     /// Lessens the requirements for structs to implement `Unsize`.
     (accepted, relaxed_struct_unsize, "1.58.0", Some(81793)),
+    /// Allows the `#[repr(i128)]` attribute for enums.
+    (accepted, repr128, "CURRENT_RUSTC_VERSION", Some(56071)),
     /// Allows `repr(align(16))` struct attribute (RFC 1358).
     (accepted, repr_align, "1.25.0", Some(33626)),
     /// Allows using `#[repr(align(X))]` on enums with equivalent semantics