Auto merge of #125423 - fmease:rollup-ne4l9y4, r=fmease

Rollup of 7 pull requests

Successful merges:

 - #125043 (reference type safety invariant docs: clarification)
 - #125306 (Force the inner coroutine of an async closure to `move` if the outer closure is `move` and `FnOnce`)
 - #125355 (Use Backtrace::force_capture instead of Backtrace::capture in rustc_log)
 - #125382 (rustdoc: rename `issue-\d+.rs` tests to have meaningful names (part 7))
 - #125391 (Minor serialize/span tweaks)
 - #125395 (Remove unnecessary `.md` from the documentation sidebar)
 - #125399 (Stop using `to_hir_binop` in codegen)

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

tests/ui/async-await/async-closures/force-move-due-to-actually-fnonce.rs

@@ -0,0 +1,27 @@
+//@ aux-build:block-on.rs
+//@ edition:2021
+//@ check-pass
+
+#![feature(async_closure)]
+
+extern crate block_on;
+
+fn consume(_: String) {}
+
+fn main() {
+    block_on::block_on(async {
+        let x = 1i32;
+        let s = String::new();
+        // `consume(s)` pulls the closure's kind down to `FnOnce`,
+        // which means that we don't treat the borrow of `x` as a
+        // self-borrow (with `'env` lifetime). This leads to a lifetime
+        // error which is solved by forcing the inner coroutine to
+        // be `move` as well, so that it moves `x`.
+        let c = async move || {
+            println!("{x}");
+            // This makes the closure FnOnce...
+            consume(s);
+        };
+        c().await;
+    });
+}

tests/ui/async-await/async-closures/force-move-due-to-inferred-kind.rs

@@ -0,0 +1,24 @@
+//@ aux-build:block-on.rs
+//@ edition:2021
+//@ check-pass
+
+#![feature(async_closure)]
+
+extern crate block_on;
+
+fn force_fnonce<T: async FnOnce()>(t: T) -> T { t }
+
+fn main() {
+    block_on::block_on(async {
+        let x = 1i32;
+        // `force_fnonce` pulls the closure's kind down to `FnOnce`,
+        // which means that we don't treat the borrow of `x` as a
+        // self-borrow (with `'env` lifetime). This leads to a lifetime
+        // error which is solved by forcing the inner coroutine to
+        // be `move` as well, so that it moves `x`.
+        let c = force_fnonce(async move || {
+            println!("{x}");
+        });
+        c().await;
+    });
+}