Auto merge of rust-lang#125010 - matthiaskrgr:rollup-270pck3, r=matth…

…iaskrgr

Rollup of 5 pull requests

Successful merges:

 - rust-lang#124928 (Stabilize `byte_slice_trim_ascii` for `&[u8]`/`&str`)
 - rust-lang#124954 (Document proper usage of `fmt::Error` and `fmt()`'s `Result`.)
 - rust-lang#124969 (check if `x test tests` missing any test directory)
 - rust-lang#124978 (Handle Deref expressions in invalid_reference_casting)
 - rust-lang#125005 (Miri subtree update)

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

compiler/rustc_lint/src/reference_casting.rs

@@ -202,8 +202,10 @@ fn is_cast_to_bigger_memory_layout<'tcx>(
 
     // if the current expr looks like this `&mut expr[index]` then just looking
     // at `expr[index]` won't give us the underlying allocation, so we just skip it
-    // the same logic applies field access like `&mut expr.field`
-    if let ExprKind::Index(..) | ExprKind::Field(..) = e_alloc.kind {
+    // the same logic applies field access `&mut expr.field` and reborrows `&mut *expr`.
+    if let ExprKind::Index(..) | ExprKind::Field(..) | ExprKind::Unary(UnOp::Deref, ..) =
+        e_alloc.kind
+    {
         return None;
     }
 

library/alloc/src/fmt.rs

@@ -403,7 +403,7 @@
 //! is, a formatting implementation must and may only return an error if the
 //! passed-in [`Formatter`] returns an error. This is because, contrary to what
 //! the function signature might suggest, string formatting is an infallible
-//! operation. This function only returns a result because writing to the
+//! operation. This function only returns a [`Result`] because writing to the
 //! underlying stream might fail and it must provide a way to propagate the fact
 //! that an error has occurred back up the stack.
 //!

library/core/src/fmt/fmt_trait_method_doc.md

@@ -0,0 +1,8 @@
+Formats the value using the given formatter.
+
+# Errors
+
+This function should return [`Err`] if, and only if, the provided [`Formatter`] returns [`Err`].
+String formatting is considered an infallible operation; this function only
+returns a [`Result`] because writing to the underlying stream might fail and it must
+provide a way to propagate the fact that an error has occurred back up the stack.

library/core/src/fmt/mod.rs

@@ -72,14 +72,24 @@ pub type Result = result::Result<(), Error>;
 /// The error type which is returned from formatting a message into a stream.
 ///
 /// This type does not support transmission of an error other than that an error
-/// occurred. Any extra information must be arranged to be transmitted through
-/// some other means.
-///
-/// An important thing to remember is that the type `fmt::Error` should not be
+/// occurred. This is because, despite the existence of this error,
+/// string formatting is considered an infallible operation.
+/// `fmt()` implementors should not return this `Error` unless they received it from their
+/// [`Formatter`]. The only time your code should create a new instance of this
+/// error is when implementing `fmt::Write`, in order to cancel the formatting operation when
+/// writing to the underlying stream fails.
+///
+/// Any extra information must be arranged to be transmitted through some other means,
+/// such as storing it in a field to be consulted after the formatting operation has been
+/// cancelled. (For example, this is how [`std::io::Write::write_fmt()`] propagates IO errors
+/// during writing.)
+///
+/// This type, `fmt::Error`, should not be
 /// confused with [`std::io::Error`] or [`std::error::Error`], which you may also
 /// have in scope.
 ///
 /// [`std::io::Error`]: ../../std/io/struct.Error.html
+/// [`std::io::Write::write_fmt()`]: ../../std/io/trait.Write.html#method.write_fmt
 /// [`std::error::Error`]: ../../std/error/trait.Error.html
 ///
 /// # Examples
@@ -118,8 +128,10 @@ pub trait Write {
     /// This function will return an instance of [`std::fmt::Error`][Error] on error.
     ///
     /// The purpose of that error is to abort the formatting operation when the underlying
-    /// destination encounters some error preventing it from accepting more text; it should
-    /// generally be propagated rather than handled, at least when implementing formatting traits.
+    /// destination encounters some error preventing it from accepting more text;
+    /// in particular, it does not communicate any information about *what* error occurred.
+    /// It should generally be propagated rather than handled, at least when implementing
+    /// formatting traits.
     ///
     /// # Examples
     ///
@@ -586,7 +598,7 @@ impl Display for Arguments<'_> {
 #[rustc_diagnostic_item = "Debug"]
 #[rustc_trivial_field_reads]
 pub trait Debug {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     ///
     /// # Examples
     ///
@@ -703,7 +715,7 @@ pub use macros::Debug;
 #[rustc_diagnostic_item = "Display"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait Display {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     ///
     /// # Examples
     ///
@@ -777,7 +789,7 @@ pub trait Display {
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait Octal {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
@@ -836,7 +848,7 @@ pub trait Octal {
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait Binary {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
@@ -891,7 +903,7 @@ pub trait Binary {
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait LowerHex {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
@@ -946,7 +958,7 @@ pub trait LowerHex {
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait UpperHex {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
@@ -997,7 +1009,7 @@ pub trait UpperHex {
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_diagnostic_item = "Pointer"]
 pub trait Pointer {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
@@ -1048,7 +1060,7 @@ pub trait Pointer {
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait LowerExp {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
@@ -1099,7 +1111,7 @@ pub trait LowerExp {
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait UpperExp {
-    /// Formats the value using the given formatter.
+    #[doc = include_str!("fmt_trait_method_doc.md")]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }

library/core/src/slice/ascii.rs

@@ -114,18 +114,17 @@ impl [u8] {
     /// Returns a byte slice with leading ASCII whitespace bytes removed.
     ///
     /// 'Whitespace' refers to the definition used by
-    /// `u8::is_ascii_whitespace`.
+    /// [`u8::is_ascii_whitespace`].
     ///
     /// # Examples
     ///
     /// ```
-    /// #![feature(byte_slice_trim_ascii)]
-    ///
     /// assert_eq!(b" \t hello world\n".trim_ascii_start(), b"hello world\n");
     /// assert_eq!(b"  ".trim_ascii_start(), b"");
     /// assert_eq!(b"".trim_ascii_start(), b"");
     /// ```
-    #[unstable(feature = "byte_slice_trim_ascii", issue = "94035")]
+    #[stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trim_ascii_start(&self) -> &[u8] {
         let mut bytes = self;
@@ -144,18 +143,17 @@ impl [u8] {
     /// Returns a byte slice with trailing ASCII whitespace bytes removed.
     ///
     /// 'Whitespace' refers to the definition used by
-    /// `u8::is_ascii_whitespace`.
+    /// [`u8::is_ascii_whitespace`].
     ///
     /// # Examples
     ///
     /// ```
-    /// #![feature(byte_slice_trim_ascii)]
-    ///
     /// assert_eq!(b"\r hello world\n ".trim_ascii_end(), b"\r hello world");
     /// assert_eq!(b"  ".trim_ascii_end(), b"");
     /// assert_eq!(b"".trim_ascii_end(), b"");
     /// ```
-    #[unstable(feature = "byte_slice_trim_ascii", issue = "94035")]
+    #[stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trim_ascii_end(&self) -> &[u8] {
         let mut bytes = self;
@@ -175,18 +173,17 @@ impl [u8] {
     /// removed.
     ///
     /// 'Whitespace' refers to the definition used by
-    /// `u8::is_ascii_whitespace`.
+    /// [`u8::is_ascii_whitespace`].
     ///
     /// # Examples
     ///
     /// ```
-    /// #![feature(byte_slice_trim_ascii)]
-    ///
     /// assert_eq!(b"\r hello world\n ".trim_ascii(), b"hello world");
     /// assert_eq!(b"  ".trim_ascii(), b"");
     /// assert_eq!(b"".trim_ascii(), b"");
     /// ```
-    #[unstable(feature = "byte_slice_trim_ascii", issue = "94035")]
+    #[stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trim_ascii(&self) -> &[u8] {
         self.trim_ascii_start().trim_ascii_end()

library/core/src/str/mod.rs

@@ -2531,15 +2531,14 @@ impl str {
     /// # Examples
     ///
     /// ```
-    /// #![feature(byte_slice_trim_ascii)]
-    ///
     /// assert_eq!(" \t \u{3000}hello world\n".trim_ascii_start(), "\u{3000}hello world\n");
     /// assert_eq!("  ".trim_ascii_start(), "");
     /// assert_eq!("".trim_ascii_start(), "");
     /// ```
-    #[unstable(feature = "byte_slice_trim_ascii", issue = "94035")]
     #[must_use = "this returns the trimmed string as a new slice, \
                   without modifying the original"]
+    #[stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trim_ascii_start(&self) -> &str {
         // SAFETY: Removing ASCII characters from a `&str` does not invalidate
@@ -2557,15 +2556,14 @@ impl str {
     /// # Examples
     ///
     /// ```
-    /// #![feature(byte_slice_trim_ascii)]
-    ///
     /// assert_eq!("\r hello world\u{3000}\n ".trim_ascii_end(), "\r hello world\u{3000}");
     /// assert_eq!("  ".trim_ascii_end(), "");
     /// assert_eq!("".trim_ascii_end(), "");
     /// ```
-    #[unstable(feature = "byte_slice_trim_ascii", issue = "94035")]
     #[must_use = "this returns the trimmed string as a new slice, \
                   without modifying the original"]
+    #[stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trim_ascii_end(&self) -> &str {
         // SAFETY: Removing ASCII characters from a `&str` does not invalidate
@@ -2584,15 +2582,14 @@ impl str {
     /// # Examples
     ///
     /// ```
-    /// #![feature(byte_slice_trim_ascii)]
-    ///
     /// assert_eq!("\r hello world\n ".trim_ascii(), "hello world");
     /// assert_eq!("  ".trim_ascii(), "");
     /// assert_eq!("".trim_ascii(), "");
     /// ```
-    #[unstable(feature = "byte_slice_trim_ascii", issue = "94035")]
     #[must_use = "this returns the trimmed string as a new slice, \
                   without modifying the original"]
+    #[stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "byte_slice_trim_ascii", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trim_ascii(&self) -> &str {
         // SAFETY: Removing ASCII characters from a `&str` does not invalidate

src/bootstrap/src/core/builder.rs

@@ -320,11 +320,13 @@ const PATH_REMAP: &[(&str, &[&str])] = &[
     (
         "tests",
         &[
+            // tidy-alphabetical-start
             "tests/assembly",
             "tests/codegen",
             "tests/codegen-units",
             "tests/coverage",
             "tests/coverage-run-rustdoc",
+            "tests/crashes",
             "tests/debuginfo",
             "tests/incremental",
             "tests/mir-opt",
@@ -340,6 +342,7 @@ const PATH_REMAP: &[(&str, &[&str])] = &[
             "tests/rustdoc-ui",
             "tests/ui",
             "tests/ui-fulldeps",
+            // tidy-alphabetical-end
         ],
     ),
 ];

src/bootstrap/src/core/builder/tests.rs

@@ -128,6 +128,26 @@ fn validate_path_remap() {
         });
 }
 
+#[test]
+fn check_missing_paths_for_x_test_tests() {
+    let build = Build::new(configure("test", &["A-A"], &["A-A"]));
+
+    let (_, tests_remap_paths) =
+        PATH_REMAP.iter().find(|(target_path, _)| *target_path == "tests").unwrap();
+
+    let tests_dir = fs::read_dir(build.src.join("tests")).unwrap();
+    for dir in tests_dir {
+        let path = dir.unwrap().path();
+
+        // Skip if not a test directory.
+        if path.ends_with("tests/auxiliary") || !path.is_dir() {
+            continue
+        }
+
+        assert!(tests_remap_paths.iter().any(|item| path.ends_with(*item)), "{} is missing in PATH_REMAP tests list.", path.display());
+    }
+}
+
 #[test]
 fn test_exclude() {
     let mut config = configure("test", &["A-A"], &["A-A"]);

src/tools/miri/.gitignore

@@ -9,5 +9,5 @@ tex/*/out
 perf.data
 perf.data.old
 flamegraph.svg
-tests/extern-so/libtestlib.so
+tests/native-lib/libtestlib.so
 .auto-*