Auto merge of rust-lang#121770 - matthiaskrgr:rollup-wdher8r, r=matthiaskrgr

Rollup of 5 pull requests

Successful merges:

 - rust-lang#110543 (Make `ReentrantLock` public)
 - rust-lang#121689 ([rustdoc] Prevent inclusion of whitespace character after macro_rules ident)
 - rust-lang#121724 (Use `LitKind::Err` for malformed floats)
 - rust-lang#121735 (pattern analysis: Don't panic when encountering unexpected constructor)
 - rust-lang#121743 (Opportunistically resolve regions when processing region outlives obligations)

Failed merges:

 - rust-lang#121326 (Detect empty leading where clauses on type aliases)
 - rust-lang#121416 (Improve error messages for generics with default parameters)
 - rust-lang#121669 (Count stashed errors again)
 - rust-lang#121723 (Two diagnostic things)

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

Author: bors

compiler/rustc_infer/src/infer/outlives/obligations.rs

@@ -62,14 +62,17 @@
 use crate::infer::outlives::components::{push_outlives_components, Component};
 use crate::infer::outlives::env::RegionBoundPairs;
 use crate::infer::outlives::verify::VerifyBoundCx;
+use crate::infer::resolve::OpportunisticRegionResolver;
 use crate::infer::{
     self, GenericKind, InferCtxt, RegionObligation, SubregionOrigin, UndoLog, VerifyBound,
 };
 use crate::traits::{ObligationCause, ObligationCauseCode};
 use rustc_data_structures::undo_log::UndoLogs;
 use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::traits::query::NoSolution;
-use rustc_middle::ty::{self, GenericArgsRef, Region, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{
+    self, GenericArgsRef, Region, Ty, TyCtxt, TypeFoldable as _, TypeVisitableExt,
+};
 use rustc_middle::ty::{GenericArgKind, PolyTypeOutlivesPredicate};
 use rustc_span::DUMMY_SP;
 use smallvec::smallvec;
@@ -176,6 +179,11 @@ impl<'tcx> InferCtxt<'tcx> {
                         .map_err(|NoSolution| (outlives, origin.clone()))?
                         .no_bound_vars()
                         .expect("started with no bound vars, should end with no bound vars");
+                // `TypeOutlives` is structural, so we should try to opportunistically resolve all
+                // region vids before processing regions, so we have a better chance to match clauses
+                // in our param-env.
+                let (sup_type, sub_region) =
+                    (sup_type, sub_region).fold_with(&mut OpportunisticRegionResolver::new(self));
 
                 debug!(?sup_type, ?sub_region, ?origin);
 

compiler/rustc_parse/src/lexer/mod.rs

@@ -501,9 +501,11 @@ impl<'sess, 'src> StringReader<'sess, 'src> {
                 (kind, self.symbol_from_to(start, end))
             }
             rustc_lexer::LiteralKind::Float { base, empty_exponent } => {
+                let mut kind = token::Float;
                 if empty_exponent {
                     let span = self.mk_sp(start, self.pos);
-                    self.dcx().emit_err(errors::EmptyExponentFloat { span });
+                    let guar = self.dcx().emit_err(errors::EmptyExponentFloat { span });
+                    kind = token::Err(guar);
                 }
                 let base = match base {
                     Base::Hexadecimal => Some("hexadecimal"),
@@ -513,9 +515,11 @@ impl<'sess, 'src> StringReader<'sess, 'src> {
                 };
                 if let Some(base) = base {
                     let span = self.mk_sp(start, end);
-                    self.dcx().emit_err(errors::FloatLiteralUnsupportedBase { span, base });
+                    let guar =
+                        self.dcx().emit_err(errors::FloatLiteralUnsupportedBase { span, base });
+                    kind = token::Err(guar)
                 }
-                (token::Float, self.symbol_from_to(start, end))
+                (kind, self.symbol_from_to(start, end))
             }
         }
     }

compiler/rustc_pattern_analysis/src/constructor.rs

@@ -940,7 +940,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
             }
             ConstructorSet::Variants { variants, non_exhaustive } => {
                 let mut seen_set = index::IdxSet::new_empty(variants.len());
-                for idx in seen.iter().map(|c| c.as_variant().unwrap()) {
+                for idx in seen.iter().filter_map(|c| c.as_variant()) {
                     seen_set.insert(idx);
                 }
                 let mut skipped_a_hidden_variant = false;
@@ -969,7 +969,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
             ConstructorSet::Bool => {
                 let mut seen_false = false;
                 let mut seen_true = false;
-                for b in seen.iter().map(|ctor| ctor.as_bool().unwrap()) {
+                for b in seen.iter().filter_map(|ctor| ctor.as_bool()) {
                     if b {
                         seen_true = true;
                     } else {
@@ -989,7 +989,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
             }
             ConstructorSet::Integers { range_1, range_2 } => {
                 let seen_ranges: Vec<_> =
-                    seen.iter().map(|ctor| *ctor.as_int_range().unwrap()).collect();
+                    seen.iter().filter_map(|ctor| ctor.as_int_range()).copied().collect();
                 for (seen, splitted_range) in range_1.split(seen_ranges.iter().cloned()) {
                     match seen {
                         Presence::Unseen => missing.push(IntRange(splitted_range)),
@@ -1006,7 +1006,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
                 }
             }
             ConstructorSet::Slice { array_len, subtype_is_empty } => {
-                let seen_slices = seen.iter().map(|c| c.as_slice().unwrap());
+                let seen_slices = seen.iter().filter_map(|c| c.as_slice());
                 let base_slice = Slice::new(*array_len, VarLen(0, 0));
                 for (seen, splitted_slice) in base_slice.split(seen_slices) {
                     let ctor = Slice(splitted_slice);

library/std/src/io/stdio.rs

@@ -11,8 +11,9 @@ use crate::fs::File;
 use crate::io::{
     self, BorrowedCursor, BufReader, IoSlice, IoSliceMut, LineWriter, Lines, SpecReadByte,
 };
+use crate::panic::{RefUnwindSafe, UnwindSafe};
 use crate::sync::atomic::{AtomicBool, Ordering};
-use crate::sync::{Arc, Mutex, MutexGuard, OnceLock, ReentrantMutex, ReentrantMutexGuard};
+use crate::sync::{Arc, Mutex, MutexGuard, OnceLock, ReentrantLock, ReentrantLockGuard};
 use crate::sys::stdio;
 
 type LocalStream = Arc<Mutex<Vec<u8>>>;
@@ -545,7 +546,7 @@ pub struct Stdout {
     // FIXME: this should be LineWriter or BufWriter depending on the state of
     //        stdout (tty or not). Note that if this is not line buffered it
     //        should also flush-on-panic or some form of flush-on-abort.
-    inner: &'static ReentrantMutex<RefCell<LineWriter<StdoutRaw>>>,
+    inner: &'static ReentrantLock<RefCell<LineWriter<StdoutRaw>>>,
 }
 
 /// A locked reference to the [`Stdout`] handle.
@@ -567,10 +568,10 @@ pub struct Stdout {
 #[must_use = "if unused stdout will immediately unlock"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct StdoutLock<'a> {
-    inner: ReentrantMutexGuard<'a, RefCell<LineWriter<StdoutRaw>>>,
+    inner: ReentrantLockGuard<'a, RefCell<LineWriter<StdoutRaw>>>,
 }
 
-static STDOUT: OnceLock<ReentrantMutex<RefCell<LineWriter<StdoutRaw>>>> = OnceLock::new();
+static STDOUT: OnceLock<ReentrantLock<RefCell<LineWriter<StdoutRaw>>>> = OnceLock::new();
 
 /// Constructs a new handle to the standard output of the current process.
 ///
@@ -624,7 +625,7 @@ static STDOUT: OnceLock<ReentrantMutex<RefCell<LineWriter<StdoutRaw>>>> = OnceLo
 pub fn stdout() -> Stdout {
     Stdout {
         inner: STDOUT
-            .get_or_init(|| ReentrantMutex::new(RefCell::new(LineWriter::new(stdout_raw())))),
+            .get_or_init(|| ReentrantLock::new(RefCell::new(LineWriter::new(stdout_raw())))),
     }
 }
 
@@ -635,7 +636,7 @@ pub fn cleanup() {
     let mut initialized = false;
     let stdout = STDOUT.get_or_init(|| {
         initialized = true;
-        ReentrantMutex::new(RefCell::new(LineWriter::with_capacity(0, stdout_raw())))
+        ReentrantLock::new(RefCell::new(LineWriter::with_capacity(0, stdout_raw())))
     });
 
     if !initialized {
@@ -678,6 +679,12 @@ impl Stdout {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for Stdout {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for Stdout {}
+
 #[stable(feature = "std_debug", since = "1.16.0")]
 impl fmt::Debug for Stdout {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -737,6 +744,12 @@ impl Write for &Stdout {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for StdoutLock<'_> {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for StdoutLock<'_> {}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Write for StdoutLock<'_> {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
@@ -786,7 +799,7 @@ impl fmt::Debug for StdoutLock<'_> {
 /// standard library or via raw Windows API calls, will fail.
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Stderr {
-    inner: &'static ReentrantMutex<RefCell<StderrRaw>>,
+    inner: &'static ReentrantLock<RefCell<StderrRaw>>,
 }
 
 /// A locked reference to the [`Stderr`] handle.
@@ -808,7 +821,7 @@ pub struct Stderr {
 #[must_use = "if unused stderr will immediately unlock"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct StderrLock<'a> {
-    inner: ReentrantMutexGuard<'a, RefCell<StderrRaw>>,
+    inner: ReentrantLockGuard<'a, RefCell<StderrRaw>>,
 }
 
 /// Constructs a new handle to the standard error of the current process.
@@ -862,8 +875,8 @@ pub fn stderr() -> Stderr {
     // Note that unlike `stdout()` we don't use `at_exit` here to register a
     // destructor. Stderr is not buffered, so there's no need to run a
     // destructor for flushing the buffer
-    static INSTANCE: ReentrantMutex<RefCell<StderrRaw>> =
-        ReentrantMutex::new(RefCell::new(stderr_raw()));
+    static INSTANCE: ReentrantLock<RefCell<StderrRaw>> =
+        ReentrantLock::new(RefCell::new(stderr_raw()));
 
     Stderr { inner: &INSTANCE }
 }
@@ -898,6 +911,12 @@ impl Stderr {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for Stderr {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for Stderr {}
+
 #[stable(feature = "std_debug", since = "1.16.0")]
 impl fmt::Debug for Stderr {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -957,6 +976,12 @@ impl Write for &Stderr {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for StderrLock<'_> {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for StderrLock<'_> {}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Write for StderrLock<'_> {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {

library/std/src/sync/mod.rs

@@ -184,7 +184,8 @@ pub use self::lazy_lock::LazyLock;
 #[stable(feature = "once_cell", since = "1.70.0")]
 pub use self::once_lock::OnceLock;
 
-pub(crate) use self::remutex::{ReentrantMutex, ReentrantMutexGuard};
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+pub use self::reentrant_lock::{ReentrantLock, ReentrantLockGuard};
 
 pub mod mpsc;
 
@@ -196,5 +197,5 @@ mod mutex;
 pub(crate) mod once;
 mod once_lock;
 mod poison;
-mod remutex;
+mod reentrant_lock;
 mod rwlock;