Auto merge of #121295 - matthiaskrgr:rollup-j2vffew, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #119808 (Store core::str::CharSearcher::utf8_size as u8)
 - #121032 (Continue reporting remaining errors instead of silently dropping them)
 - #121041 (Add `Future` and `IntoFuture` to the 2024 prelude)
 - #121230 (Extend Level API)
 - #121272 (Add diagnostic items for legacy numeric constants)
 - #121275 (add test for panicking attribute macros)

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

7 files changed, 64 insertions, 16 deletions

diff --git a/library/core/src/num/f32.rs b/library/core/src/num/f32.rs
index 047cb64ce50..47e16018a47 100644
--- a/library/core/src/num/f32.rs
+++ b/library/core/src/num/f32.rs
@@ -32,6 +32,7 @@ use crate::num::FpCategory;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `RADIX` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_radix"]
 pub const RADIX: u32 = f32::RADIX;
 
 /// Number of significant digits in base 2.
@@ -52,6 +53,7 @@ pub const RADIX: u32 = f32::RADIX;
     since = "TBD",
     note = "replaced by the `MANTISSA_DIGITS` associated constant on `f32`"
 )]
+#[rustc_diagnostic_item = "f32_legacy_const_mantissa_dig"]
 pub const MANTISSA_DIGITS: u32 = f32::MANTISSA_DIGITS;
 
 /// Approximate number of significant digits in base 10.
@@ -69,6 +71,7 @@ pub const MANTISSA_DIGITS: u32 = f32::MANTISSA_DIGITS;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `DIGITS` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_digits"]
 pub const DIGITS: u32 = f32::DIGITS;
 
 /// [Machine epsilon] value for `f32`.
@@ -90,6 +93,7 @@ pub const DIGITS: u32 = f32::DIGITS;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `EPSILON` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_epsilon"]
 pub const EPSILON: f32 = f32::EPSILON;
 
 /// Smallest finite `f32` value.
@@ -107,6 +111,7 @@ pub const EPSILON: f32 = f32::EPSILON;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_min"]
 pub const MIN: f32 = f32::MIN;
 
 /// Smallest positive normal `f32` value.
@@ -124,6 +129,7 @@ pub const MIN: f32 = f32::MIN;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN_POSITIVE` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_min_positive"]
 pub const MIN_POSITIVE: f32 = f32::MIN_POSITIVE;
 
 /// Largest finite `f32` value.
@@ -141,6 +147,7 @@ pub const MIN_POSITIVE: f32 = f32::MIN_POSITIVE;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_max"]
 pub const MAX: f32 = f32::MAX;
 
 /// One greater than the minimum possible normal power of 2 exponent.
@@ -158,6 +165,7 @@ pub const MAX: f32 = f32::MAX;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN_EXP` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_min_exp"]
 pub const MIN_EXP: i32 = f32::MIN_EXP;
 
 /// Maximum possible power of 2 exponent.
@@ -175,6 +183,7 @@ pub const MIN_EXP: i32 = f32::MIN_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MAX_EXP` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_max_exp"]
 pub const MAX_EXP: i32 = f32::MAX_EXP;
 
 /// Minimum possible normal power of 10 exponent.
@@ -192,6 +201,7 @@ pub const MAX_EXP: i32 = f32::MAX_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN_10_EXP` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_min_10_exp"]
 pub const MIN_10_EXP: i32 = f32::MIN_10_EXP;
 
 /// Maximum possible power of 10 exponent.
@@ -209,6 +219,7 @@ pub const MIN_10_EXP: i32 = f32::MIN_10_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MAX_10_EXP` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_max_10_exp"]
 pub const MAX_10_EXP: i32 = f32::MAX_10_EXP;
 
 /// Not a Number (NaN).
@@ -226,6 +237,7 @@ pub const MAX_10_EXP: i32 = f32::MAX_10_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `NAN` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_nan"]
 pub const NAN: f32 = f32::NAN;
 
 /// Infinity (∞).
@@ -243,6 +255,7 @@ pub const NAN: f32 = f32::NAN;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `INFINITY` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_infinity"]
 pub const INFINITY: f32 = f32::INFINITY;
 
 /// Negative infinity (−∞).
@@ -260,6 +273,7 @@ pub const INFINITY: f32 = f32::INFINITY;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `NEG_INFINITY` associated constant on `f32`")]
+#[rustc_diagnostic_item = "f32_legacy_const_neg_infinity"]
 pub const NEG_INFINITY: f32 = f32::NEG_INFINITY;
 
 /// Basic mathematical constants.
diff --git a/library/core/src/num/f64.rs b/library/core/src/num/f64.rs
index 16d81941935..cd69e758d28 100644
--- a/library/core/src/num/f64.rs
+++ b/library/core/src/num/f64.rs
@@ -32,6 +32,7 @@ use crate::num::FpCategory;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `RADIX` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_radix"]
 pub const RADIX: u32 = f64::RADIX;
 
 /// Number of significant digits in base 2.
@@ -52,6 +53,7 @@ pub const RADIX: u32 = f64::RADIX;
     since = "TBD",
     note = "replaced by the `MANTISSA_DIGITS` associated constant on `f64`"
 )]
+#[rustc_diagnostic_item = "f64_legacy_const_mantissa_dig"]
 pub const MANTISSA_DIGITS: u32 = f64::MANTISSA_DIGITS;
 
 /// Approximate number of significant digits in base 10.
@@ -69,6 +71,7 @@ pub const MANTISSA_DIGITS: u32 = f64::MANTISSA_DIGITS;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `DIGITS` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_digits"]
 pub const DIGITS: u32 = f64::DIGITS;
 
 /// [Machine epsilon] value for `f64`.
@@ -90,6 +93,7 @@ pub const DIGITS: u32 = f64::DIGITS;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `EPSILON` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_epsilon"]
 pub const EPSILON: f64 = f64::EPSILON;
 
 /// Smallest finite `f64` value.
@@ -107,6 +111,7 @@ pub const EPSILON: f64 = f64::EPSILON;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_min"]
 pub const MIN: f64 = f64::MIN;
 
 /// Smallest positive normal `f64` value.
@@ -124,6 +129,7 @@ pub const MIN: f64 = f64::MIN;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN_POSITIVE` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_min_positive"]
 pub const MIN_POSITIVE: f64 = f64::MIN_POSITIVE;
 
 /// Largest finite `f64` value.
@@ -141,6 +147,7 @@ pub const MIN_POSITIVE: f64 = f64::MIN_POSITIVE;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_max"]
 pub const MAX: f64 = f64::MAX;
 
 /// One greater than the minimum possible normal power of 2 exponent.
@@ -158,6 +165,7 @@ pub const MAX: f64 = f64::MAX;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN_EXP` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_min_exp"]
 pub const MIN_EXP: i32 = f64::MIN_EXP;
 
 /// Maximum possible power of 2 exponent.
@@ -175,6 +183,7 @@ pub const MIN_EXP: i32 = f64::MIN_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MAX_EXP` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_max_exp"]
 pub const MAX_EXP: i32 = f64::MAX_EXP;
 
 /// Minimum possible normal power of 10 exponent.
@@ -192,6 +201,7 @@ pub const MAX_EXP: i32 = f64::MAX_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MIN_10_EXP` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_min_10_exp"]
 pub const MIN_10_EXP: i32 = f64::MIN_10_EXP;
 
 /// Maximum possible power of 10 exponent.
@@ -209,6 +219,7 @@ pub const MIN_10_EXP: i32 = f64::MIN_10_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `MAX_10_EXP` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_max_10_exp"]
 pub const MAX_10_EXP: i32 = f64::MAX_10_EXP;
 
 /// Not a Number (NaN).
@@ -226,6 +237,7 @@ pub const MAX_10_EXP: i32 = f64::MAX_10_EXP;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `NAN` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_nan"]
 pub const NAN: f64 = f64::NAN;
 
 /// Infinity (∞).
@@ -243,6 +255,7 @@ pub const NAN: f64 = f64::NAN;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `INFINITY` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_infinity"]
 pub const INFINITY: f64 = f64::INFINITY;
 
 /// Negative infinity (−∞).
@@ -260,6 +273,7 @@ pub const INFINITY: f64 = f64::INFINITY;
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[deprecated(since = "TBD", note = "replaced by the `NEG_INFINITY` associated constant on `f64`")]
+#[rustc_diagnostic_item = "f64_legacy_const_neg_infinity"]
 pub const NEG_INFINITY: f64 = f64::NEG_INFINITY;
 
 /// Basic mathematical constants.
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 434bcace616..fa37ee4ffb2 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -3507,6 +3507,7 @@ macro_rules! int_impl {
         #[rustc_promotable]
         #[rustc_const_stable(feature = "const_min_value", since = "1.32.0")]
         #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on this type")]
+        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_min_value")]
         pub const fn min_value() -> Self {
             Self::MIN
         }
@@ -3520,6 +3521,7 @@ macro_rules! int_impl {
         #[rustc_promotable]
         #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")]
         #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on this type")]
+        #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_max_value")]
         pub const fn max_value() -> Self {
             Self::MAX
         }
diff --git a/library/core/src/num/shells/int_macros.rs b/library/core/src/num/shells/int_macros.rs
index 2b1133e11a5..8ae9b7abae3 100644
--- a/library/core/src/num/shells/int_macros.rs
+++ b/library/core/src/num/shells/int_macros.rs
@@ -20,6 +20,7 @@ macro_rules! int_module {
         ///
         #[$attr]
         #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on this type")]
+        #[rustc_diagnostic_item = concat!(stringify!($T), "_legacy_const_min")]
         pub const MIN: $T = $T::MIN;
 
         #[doc = concat!(
@@ -39,6 +40,7 @@ macro_rules! int_module {
         ///
         #[$attr]
         #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on this type")]
+        #[rustc_diagnostic_item = concat!(stringify!($T), "_legacy_const_max")]
         pub const MAX: $T = $T::MAX;
     )
 }
diff --git a/library/core/src/prelude/mod.rs b/library/core/src/prelude/mod.rs
index 12f762ef193..b4791c2c022 100644
--- a/library/core/src/prelude/mod.rs
+++ b/library/core/src/prelude/mod.rs
@@ -49,9 +49,13 @@ pub mod rust_2021 {
 /// The 2024 edition of the core prelude.
 ///
 /// See the [module-level documentation](self) for more.
-#[unstable(feature = "prelude_2024", issue = "none")]
+#[unstable(feature = "prelude_2024", issue = "121042")]
 pub mod rust_2024 {
-    #[unstable(feature = "prelude_2024", issue = "none")]
+    #[unstable(feature = "prelude_2024", issue = "121042")]
     #[doc(no_inline)]
     pub use super::rust_2021::*;
+
+    #[unstable(feature = "prelude_2024", issue = "121042")]
+    #[doc(no_inline)]
+    pub use crate::future::{Future, IntoFuture};
 }
diff --git a/library/core/src/str/pattern.rs b/library/core/src/str/pattern.rs
index caa54e00f31..cc66da25795 100644
--- a/library/core/src/str/pattern.rs
+++ b/library/core/src/str/pattern.rs
@@ -40,6 +40,7 @@
 
 use crate::cmp;
 use crate::cmp::Ordering;
+use crate::convert::TryInto as _;
 use crate::fmt;
 use crate::slice::memchr;
 
@@ -370,11 +371,17 @@ pub struct CharSearcher<'a> {
 
     // safety invariant: `utf8_size` must be less than 5
     /// The number of bytes `needle` takes up when encoded in utf8.
-    utf8_size: usize,
+    utf8_size: u8,
     /// A utf8 encoded copy of the `needle`
     utf8_encoded: [u8; 4],
 }
 
+impl CharSearcher<'_> {
+    fn utf8_size(&self) -> usize {
+        self.utf8_size.into()
+    }
+}
+
 unsafe impl<'a> Searcher<'a> for CharSearcher<'a> {
     #[inline]
     fn haystack(&self) -> &'a str {
@@ -414,7 +421,7 @@ unsafe impl<'a> Searcher<'a> for CharSearcher<'a> {
             let bytes = self.haystack.as_bytes().get(self.finger..self.finger_back)?;
             // the last byte of the utf8 encoded needle
             // SAFETY: we have an invariant that `utf8_size < 5`
-            let last_byte = unsafe { *self.utf8_encoded.get_unchecked(self.utf8_size - 1) };
+            let last_byte = unsafe { *self.utf8_encoded.get_unchecked(self.utf8_size() - 1) };
             if let Some(index) = memchr::memchr(last_byte, bytes) {
                 // The new finger is the index of the byte we found,
                 // plus one, since we memchr'd for the last byte of the character.
@@ -434,10 +441,10 @@ unsafe impl<'a> Searcher<'a> for CharSearcher<'a> {
                 // find something. When we find something the `finger` will be set
                 // to a UTF8 boundary.
                 self.finger += index + 1;
-                if self.finger >= self.utf8_size {
-                    let found_char = self.finger - self.utf8_size;
+                if self.finger >= self.utf8_size() {
+                    let found_char = self.finger - self.utf8_size();
                     if let Some(slice) = self.haystack.as_bytes().get(found_char..self.finger) {
-                        if slice == &self.utf8_encoded[0..self.utf8_size] {
+                        if slice == &self.utf8_encoded[0..self.utf8_size()] {
                             return Some((found_char, self.finger));
                         }
                     }
@@ -482,7 +489,7 @@ unsafe impl<'a> ReverseSearcher<'a> for CharSearcher<'a> {
             let bytes = haystack.get(self.finger..self.finger_back)?;
             // the last byte of the utf8 encoded needle
             // SAFETY: we have an invariant that `utf8_size < 5`
-            let last_byte = unsafe { *self.utf8_encoded.get_unchecked(self.utf8_size - 1) };
+            let last_byte = unsafe { *self.utf8_encoded.get_unchecked(self.utf8_size() - 1) };
             if let Some(index) = memchr::memrchr(last_byte, bytes) {
                 // we searched a slice that was offset by self.finger,
                 // add self.finger to recoup the original index
@@ -493,14 +500,14 @@ unsafe impl<'a> ReverseSearcher<'a> for CharSearcher<'a> {
                 // char in the paradigm of reverse iteration). For
                 // multibyte chars we need to skip down by the number of more
                 // bytes they have than ASCII
-                let shift = self.utf8_size - 1;
+                let shift = self.utf8_size() - 1;
                 if index >= shift {
                     let found_char = index - shift;
-                    if let Some(slice) = haystack.get(found_char..(found_char + self.utf8_size)) {
-                        if slice == &self.utf8_encoded[0..self.utf8_size] {
+                    if let Some(slice) = haystack.get(found_char..(found_char + self.utf8_size())) {
+                        if slice == &self.utf8_encoded[0..self.utf8_size()] {
                             // move finger to before the character found (i.e., at its start index)
                             self.finger_back = found_char;
-                            return Some((self.finger_back, self.finger_back + self.utf8_size));
+                            return Some((self.finger_back, self.finger_back + self.utf8_size()));
                         }
                     }
                 }
@@ -542,7 +549,12 @@ impl<'a> Pattern<'a> for char {
     #[inline]
     fn into_searcher(self, haystack: &'a str) -> Self::Searcher {
         let mut utf8_encoded = [0; 4];
-        let utf8_size = self.encode_utf8(&mut utf8_encoded).len();
+        let utf8_size = self
+            .encode_utf8(&mut utf8_encoded)
+            .len()
+            .try_into()
+            .expect("char len should be less than 255");
+
         CharSearcher {
             haystack,
             finger: 0,
diff --git a/library/std/src/prelude/mod.rs b/library/std/src/prelude/mod.rs
index 1b29c887d21..7d44d2e4b5d 100644
--- a/library/std/src/prelude/mod.rs
+++ b/library/std/src/prelude/mod.rs
@@ -132,13 +132,13 @@ pub mod rust_2021 {
 /// The 2024 version of the prelude of The Rust Standard Library.
 ///
 /// See the [module-level documentation](self) for more.
-#[unstable(feature = "prelude_2024", issue = "none")]
+#[unstable(feature = "prelude_2024", issue = "121042")]
 pub mod rust_2024 {
-    #[unstable(feature = "prelude_2024", issue = "none")]
+    #[unstable(feature = "prelude_2024", issue = "121042")]
     #[doc(no_inline)]
     pub use super::v1::*;
 
-    #[unstable(feature = "prelude_2024", issue = "none")]
+    #[unstable(feature = "prelude_2024", issue = "121042")]
     #[doc(no_inline)]
     pub use core::prelude::rust_2024::*;
 }