Auto merge of #57882 - euclio:unused-doc-attributes, r=estebank

overhaul unused doc comments lint

This PR contains a number of improvements to the `unused_doc_comments` lint.

- Extends the span to cover the entire comment when using sugared doc comments.
- Triggers the lint for all unused doc comments on a node, instead of just the first one.
- Triggers the lint on macro expansions, and provides a help note explaining that doc comments must be expanded by the macro.
- Adds a label pointing at the node that cannot be documented.

Furthermore, this PR fixes any instances in rustc where a macro expansion was erroneously documented.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/libstd/io/stdio.rs b/src/libstd/io/stdio.rs
index 589fb455a19..d53a294fa6a 100644
--- a/src/libstd/io/stdio.rs
+++ b/src/libstd/io/stdio.rs
@@ -11,15 +11,15 @@ use crate::sys::stdio;
 use crate::sys_common::remutex::{ReentrantMutex, ReentrantMutexGuard};
 use crate::thread::LocalKey;
 
-/// Stdout used by print! and println! macros
 thread_local! {
+    /// Stdout used by print! and println! macros
     static LOCAL_STDOUT: RefCell<Option<Box<dyn Write + Send>>> = {
         RefCell::new(None)
     }
 }
 
-/// Stderr used by eprint! and eprintln! macros, and panics
 thread_local! {
+    /// Stderr used by eprint! and eprintln! macros, and panics
     static LOCAL_STDERR: RefCell<Option<Box<dyn Write + Send>>> = {
         RefCell::new(None)
     }