Auto merge of #101938 - Dylan-DPC:rollup-6vlohhs, r=Dylan-DPC

Rollup of 6 pull requests

Successful merges:

 - #93628 (Stabilize `let else`)
 - #98441 (Implement simd_as for pointers)
 - #101790 (Do not suggest a placeholder to const and static without a type)
 - #101807 (Disallow defaults on type GATs)
 - #101915 (doc: fix redirected link in `/index.html`)
 - #101931 (doc: Fix a typo in `Rc::make_mut` docstring)

Failed merges:

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

Author: bors

alloc/src/lib.rs

@@ -169,7 +169,7 @@
 #![cfg_attr(not(test), feature(generator_trait))]
 #![feature(hashmap_internals)]
 #![feature(lang_items)]
-#![feature(let_else)]
+#![cfg_attr(bootstrap, feature(let_else))]
 #![feature(min_specialization)]
 #![feature(negative_impls)]
 #![feature(never_type)]

alloc/src/rc.rs

@@ -1142,7 +1142,7 @@ impl<T: Clone> Rc<T> {
     /// be cloned.
     ///
     /// See also [`get_mut`], which will fail rather than cloning the inner value
-    /// or diassociating [`Weak`] pointers.
+    /// or disassociating [`Weak`] pointers.
     ///
     /// [`clone`]: Clone::clone
     /// [`get_mut`]: Rc::get_mut

std/src/lib.rs

@@ -255,7 +255,7 @@
 #![cfg_attr(bootstrap, feature(label_break_value))]
 #![feature(lang_items)]
 #![feature(let_chains)]
-#![feature(let_else)]
+#![cfg_attr(bootstrap, feature(let_else))]
 #![feature(linkage)]
 #![feature(link_cfg)]
 #![feature(min_specialization)]