Auto merge of #68011 - JohnTitor:rollup-44s8twu, r=JohnTitor

Rollup of 10 pull requests

Successful merges:

 - #67774 (Try statx for all linux-gnu target.)
 - #67781 (Move `is_min_const_fn` query to librustc_mir.)
 - #67798 (Remove wrong advice about spin locks from `spin_loop_hint` docs)
 - #67849 (Add a check for swapped words when we can't find an identifier)
 - #67875 (Distinguish between private items and hidden items in rustdoc)
 - #67887 (`Option::{expect,unwrap}` and `Result::{expect, expect_err, unwrap, unwrap_err}` have `#[track_caller]`)
 - #67955 (rustdoc: Remove more `#[doc(cfg(..))]` duplicates)
 - #67977 (Updates for VxWorks)
 - #67985 (Remove insignificant notes from CStr documentation)
 - #68003 (ci: fix wrong shared.sh import for publish_toolstate)

Failed merges:

 - #67820 (Parse the syntax described in RFC 2632)
 - #67979 (Move `intravisit` => `rustc_hir` + misc cleanup)

r? @ghost

src/ci/publish_toolstate.sh

@@ -3,7 +3,7 @@
 set -euo pipefail
 IFS=$'\n\t'
 
-source "$(cd "$(dirname "$0")" && pwd)/../shared.sh"
+source "$(cd "$(dirname "$0")" && pwd)/shared.sh"
 
 # The following lines are also found in src/bootstrap/toolstate.rs,
 # so if updating here, please also update that file.

src/libcore/option.rs

@@ -341,6 +341,7 @@ impl<T> Option<T> {
     /// x.expect("the world is ending"); // panics with `the world is ending`
     /// ```
     #[inline]
+    #[track_caller]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn expect(self, msg: &str) -> T {
         match self {
@@ -374,6 +375,7 @@ impl<T> Option<T> {
     /// assert_eq!(x.unwrap(), "air"); // fails
     /// ```
     #[inline]
+    #[track_caller]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn unwrap(self) -> T {
         match self {
@@ -1015,6 +1017,7 @@ impl<T: fmt::Debug> Option<T> {
     /// }
     /// ```
     #[inline]
+    #[track_caller]
     #[unstable(feature = "option_expect_none", reason = "newly added", issue = "62633")]
     pub fn expect_none(self, msg: &str) {
         if let Some(val) = self {
@@ -1057,6 +1060,7 @@ impl<T: fmt::Debug> Option<T> {
     /// }
     /// ```
     #[inline]
+    #[track_caller]
     #[unstable(feature = "option_unwrap_none", reason = "newly added", issue = "62633")]
     pub fn unwrap_none(self) {
         if let Some(val) = self {
@@ -1184,13 +1188,15 @@ impl<T, E> Option<Result<T, E>> {
 // This is a separate function to reduce the code size of .expect() itself.
 #[inline(never)]
 #[cold]
+#[track_caller]
 fn expect_failed(msg: &str) -> ! {
     panic!("{}", msg)
 }
 
 // This is a separate function to reduce the code size of .expect_none() itself.
 #[inline(never)]
 #[cold]
+#[track_caller]
 fn expect_none_failed(msg: &str, value: &dyn fmt::Debug) -> ! {
     panic!("{}: {:?}", msg, value)
 }

src/libcore/result.rs

@@ -957,6 +957,7 @@ impl<T, E: fmt::Debug> Result<T, E> {
     /// x.unwrap(); // panics with `emergency failure`
     /// ```
     #[inline]
+    #[track_caller]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn unwrap(self) -> T {
         match self {
@@ -984,6 +985,7 @@ impl<T, E: fmt::Debug> Result<T, E> {
     /// x.expect("Testing expect"); // panics with `Testing expect: emergency failure`
     /// ```
     #[inline]
+    #[track_caller]
     #[stable(feature = "result_expect", since = "1.4.0")]
     pub fn expect(self, msg: &str) -> T {
         match self {
@@ -1017,6 +1019,7 @@ impl<T: fmt::Debug, E> Result<T, E> {
     /// assert_eq!(x.unwrap_err(), "emergency failure");
     /// ```
     #[inline]
+    #[track_caller]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn unwrap_err(self) -> E {
         match self {
@@ -1044,6 +1047,7 @@ impl<T: fmt::Debug, E> Result<T, E> {
     /// x.expect_err("Testing expect_err"); // panics with `Testing expect_err: 10`
     /// ```
     #[inline]
+    #[track_caller]
     #[stable(feature = "result_expect_err", since = "1.17.0")]
     pub fn expect_err(self, msg: &str) -> E {
         match self {
@@ -1188,6 +1192,7 @@ impl<T, E> Result<Option<T>, E> {
 // This is a separate function to reduce the code size of the methods
 #[inline(never)]
 #[cold]
+#[track_caller]
 fn unwrap_failed(msg: &str, error: &dyn fmt::Debug) -> ! {
     panic!("{}: {:?}", msg, error)
 }

src/libcore/sync/atomic.rs

@@ -134,16 +134,10 @@ use crate::hint::spin_loop;
 /// This function is different from [`std::thread::yield_now`] which directly yields to the
 /// system's scheduler, whereas `spin_loop_hint` does not interact with the operating system.
 ///
-/// Spin locks can be very efficient for short lock durations because they do not involve context
-/// switches or interaction with the operating system. For long lock durations they become wasteful
-/// however because they use CPU cycles for the entire lock duration, and using a
-/// [`std::sync::Mutex`] is likely the better approach. If actively spinning for a long time is
-/// required, e.g. because code polls a non-blocking API, calling [`std::thread::yield_now`]
-/// or [`std::thread::sleep`] may be the best option.
-///
-/// **Note**: Spin locks are based on the underlying assumption that another thread will release
-/// the lock 'soon'. In order for this to work, that other thread must run on a different CPU or
-/// core (at least potentially). Spin locks do not work efficiently on single CPU / core platforms.
+/// A common use case for `spin_loop_hint` is implementing bounded optimistic spinning in a CAS
+/// loop in synchronization primitives. To avoid problems like priority inversion, it is strongly
+/// recommended that the spin loop is terminated after a finite amount of iterations and an
+/// appropriate blocking syscall is made.
 ///
 /// **Note**: On platforms that do not support receiving spin-loop hints this function does not
 /// do anything at all.

src/librustc/ty/mod.rs

@@ -97,7 +97,6 @@ pub mod cast;
 #[macro_use]
 pub mod codec;
 pub mod _match;
-mod constness;
 mod erase_regions;
 pub mod error;
 pub mod fast_reject;
@@ -3318,7 +3317,6 @@ pub fn provide(providers: &mut ty::query::Providers<'_>) {
     context::provide(providers);
     erase_regions::provide(providers);
     layout::provide(providers);
-    constness::provide(providers);
     *providers = ty::query::Providers {
         asyncness,
         associated_item,

src/librustc_mir/const_eval.rs

@@ -9,10 +9,12 @@ use crate::interpret::{intern_const_alloc_recursive, ConstValue, InterpCx};
 
 mod error;
 mod eval_queries;
+mod fn_queries;
 mod machine;
 
 pub use error::*;
 pub use eval_queries::*;
+pub use fn_queries::*;
 pub use machine::*;
 
 /// Extracts a field of a (variant of a) const.