diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs
index ec2c703ad495d..a2fadb13a5741 100644
--- a/compiler/rustc_feature/src/active.rs
+++ b/compiler/rustc_feature/src/active.rs
@@ -678,6 +678,9 @@ declare_features! (
     /// Allows `#[doc(cfg_hide(...))]`.
     (active, doc_cfg_hide, "1.57.0", Some(43781), None),
 
+    /// Allows using the `non_exhaustive_omitted_patterns` lint.
+    (active, non_exhaustive_omitted_patterns_lint, "1.57.0", Some(89554), None),
+
     // -------------------------------------------------------------------------
     // feature-group-end: actual feature gates
     // -------------------------------------------------------------------------
diff --git a/compiler/rustc_lint_defs/src/builtin.rs b/compiler/rustc_lint_defs/src/builtin.rs
index 7a51e1e321a2a..a93d18950dba9 100644
--- a/compiler/rustc_lint_defs/src/builtin.rs
+++ b/compiler/rustc_lint_defs/src/builtin.rs
@@ -6,6 +6,7 @@
 
 use crate::{declare_lint, declare_lint_pass, FutureIncompatibilityReason};
 use rustc_span::edition::Edition;
+use rustc_span::symbol::sym;
 
 declare_lint! {
     /// The `forbidden_lint_groups` lint detects violations of
@@ -3476,6 +3477,8 @@ declare_lint! {
     /// }
     ///
     /// // in crate B
+    /// #![feature(non_exhaustive_omitted_patterns_lint)]
+    ///
     /// match Bar::A {
     ///     Bar::A => {},
     ///     #[warn(non_exhaustive_omitted_patterns)]
@@ -3512,6 +3515,7 @@ declare_lint! {
     pub NON_EXHAUSTIVE_OMITTED_PATTERNS,
     Allow,
     "detect when patterns of types marked `non_exhaustive` are missed",
+    @feature_gate = sym::non_exhaustive_omitted_patterns_lint;
 }
 
 declare_lint! {
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 0e30e154ee57c..9551120ca5522 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -893,6 +893,7 @@ symbols! {
         nomem,
         non_ascii_idents,
         non_exhaustive,
+        non_exhaustive_omitted_patterns_lint,
         non_modrs_mods,
         none_error,
         nontemporal_store,
diff --git a/library/alloc/src/collections/btree/set.rs b/library/alloc/src/collections/btree/set.rs
index 16150ceeb62c1..f4c1010098256 100644
--- a/library/alloc/src/collections/btree/set.rs
+++ b/library/alloc/src/collections/btree/set.rs
@@ -534,6 +534,7 @@ impl<T> BTreeSet<T> {
     /// b.insert(1);
     /// assert_eq!(a.is_disjoint(&b), false);
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn is_disjoint(&self, other: &BTreeSet<T>) -> bool
     where
@@ -559,6 +560,7 @@ impl<T> BTreeSet<T> {
     /// set.insert(4);
     /// assert_eq!(set.is_subset(&sup), false);
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn is_subset(&self, other: &BTreeSet<T>) -> bool
     where
@@ -638,6 +640,7 @@ impl<T> BTreeSet<T> {
     /// set.insert(2);
     /// assert_eq!(set.is_superset(&sub), true);
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn is_superset(&self, other: &BTreeSet<T>) -> bool
     where
diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs
index dd04f782f940a..89ab11fb97e10 100644
--- a/library/alloc/src/lib.rs
+++ b/library/alloc/src/lib.rs
@@ -73,6 +73,7 @@
         not(test),
         not(any(test, bootstrap)),
         any(not(feature = "miri-test-libstd"), test, doctest),
+        no_global_oom_handling,
         target_has_atomic = "ptr"
     ))
 )]
diff --git a/library/core/src/char/methods.rs b/library/core/src/char/methods.rs
index b3af1f1ffb592..45f7540d314be 100644
--- a/library/core/src/char/methods.rs
+++ b/library/core/src/char/methods.rs
@@ -377,6 +377,8 @@ impl char {
     /// ```
     /// assert_eq!('❤'.escape_unicode().to_string(), "\\u{2764}");
     /// ```
+    #[must_use = "this returns the escaped char as an iterator, \
+                  without modifying the original"]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn escape_unicode(self) -> EscapeUnicode {
@@ -453,6 +455,8 @@ impl char {
     /// ```
     /// assert_eq!('\n'.escape_debug().to_string(), "\\n");
     /// ```
+    #[must_use = "this returns the escaped char as an iterator, \
+                  without modifying the original"]
     #[stable(feature = "char_escape_debug", since = "1.20.0")]
     #[inline]
     pub fn escape_debug(self) -> EscapeDebug {
@@ -507,6 +511,8 @@ impl char {
     /// ```
     /// assert_eq!('"'.escape_default().to_string(), "\\\"");
     /// ```
+    #[must_use = "this returns the escaped char as an iterator, \
+                  without modifying the original"]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn escape_default(self) -> EscapeDefault {
@@ -692,6 +698,7 @@ impl char {
     /// // love is many things, but it is not alphabetic
     /// assert!(!c.is_alphabetic());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_alphabetic(self) -> bool {
@@ -724,6 +731,7 @@ impl char {
     /// assert!(!'中'.is_lowercase());
     /// assert!(!' '.is_lowercase());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_lowercase(self) -> bool {
@@ -756,6 +764,7 @@ impl char {
     /// assert!(!'中'.is_uppercase());
     /// assert!(!' '.is_uppercase());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_uppercase(self) -> bool {
@@ -784,6 +793,7 @@ impl char {
     ///
     /// assert!(!'越'.is_whitespace());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_whitespace(self) -> bool {
@@ -812,6 +822,7 @@ impl char {
     /// assert!('و'.is_alphanumeric());
     /// assert!('藏'.is_alphanumeric());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_alphanumeric(self) -> bool {
@@ -837,6 +848,7 @@ impl char {
     /// assert!('œ'.is_control());
     /// assert!(!'q'.is_control());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_control(self) -> bool {
@@ -852,6 +864,7 @@ impl char {
     /// [uax29]: https://www.unicode.org/reports/tr29/
     /// [ucd]: https://www.unicode.org/reports/tr44/
     /// [`DerivedCoreProperties.txt`]: https://www.unicode.org/Public/UCD/latest/ucd/DerivedCoreProperties.txt
+    #[must_use]
     #[inline]
     pub(crate) fn is_grapheme_extended(self) -> bool {
         unicode::Grapheme_Extend(self)
@@ -881,6 +894,7 @@ impl char {
     /// assert!(!'و'.is_numeric());
     /// assert!(!'藏'.is_numeric());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
     pub fn is_numeric(self) -> bool {
@@ -1060,6 +1074,7 @@ impl char {
     /// assert!(ascii.is_ascii());
     /// assert!(!non_ascii.is_ascii());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")]
     #[rustc_const_stable(feature = "const_ascii_methods_on_intrinsics", since = "1.32.0")]
     #[inline]
@@ -1237,6 +1252,7 @@ impl char {
     /// assert!(!lf.is_ascii_alphabetic());
     /// assert!(!esc.is_ascii_alphabetic());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1270,6 +1286,7 @@ impl char {
     /// assert!(!lf.is_ascii_uppercase());
     /// assert!(!esc.is_ascii_uppercase());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1303,6 +1320,7 @@ impl char {
     /// assert!(!lf.is_ascii_lowercase());
     /// assert!(!esc.is_ascii_lowercase());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1339,6 +1357,7 @@ impl char {
     /// assert!(!lf.is_ascii_alphanumeric());
     /// assert!(!esc.is_ascii_alphanumeric());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1372,6 +1391,7 @@ impl char {
     /// assert!(!lf.is_ascii_digit());
     /// assert!(!esc.is_ascii_digit());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1408,6 +1428,7 @@ impl char {
     /// assert!(!lf.is_ascii_hexdigit());
     /// assert!(!esc.is_ascii_hexdigit());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1445,6 +1466,7 @@ impl char {
     /// assert!(!lf.is_ascii_punctuation());
     /// assert!(!esc.is_ascii_punctuation());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1478,6 +1500,7 @@ impl char {
     /// assert!(!lf.is_ascii_graphic());
     /// assert!(!esc.is_ascii_graphic());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1528,6 +1551,7 @@ impl char {
     /// assert!(lf.is_ascii_whitespace());
     /// assert!(!esc.is_ascii_whitespace());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -1563,6 +1587,7 @@ impl char {
     /// assert!(lf.is_ascii_control());
     /// assert!(esc.is_ascii_control());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index e10d01b58b017..7bc641c52767d 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -65,6 +65,7 @@
     doc(cfg_hide(
         not(test),
         any(not(feature = "miri-test-libstd"), test, doctest),
+        no_fp_fmt_parse,
         target_pointer_width = "16",
         target_pointer_width = "32",
         target_pointer_width = "64",
diff --git a/library/core/src/num/f32.rs b/library/core/src/num/f32.rs
index c47a2e8b05c4b..d3dd710f7c05f 100644
--- a/library/core/src/num/f32.rs
+++ b/library/core/src/num/f32.rs
@@ -436,6 +436,7 @@ impl f32 {
     /// assert!(nan.is_nan());
     /// assert!(!f.is_nan());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -467,6 +468,7 @@ impl f32 {
     /// assert!(inf.is_infinite());
     /// assert!(neg_inf.is_infinite());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -488,6 +490,7 @@ impl f32 {
     /// assert!(!inf.is_finite());
     /// assert!(!neg_inf.is_finite());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -515,6 +518,7 @@ impl f32 {
     /// assert!(lower_than_min.is_subnormal());
     /// ```
     /// [subnormal]: https://en.wikipedia.org/wiki/Denormal_number
+    #[must_use]
     #[stable(feature = "is_subnormal", since = "1.53.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -541,6 +545,7 @@ impl f32 {
     /// assert!(!lower_than_min.is_normal());
     /// ```
     /// [subnormal]: https://en.wikipedia.org/wiki/Denormal_number
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -587,6 +592,7 @@ impl f32 {
     /// assert!(f.is_sign_positive());
     /// assert!(!g.is_sign_positive());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -604,6 +610,7 @@ impl f32 {
     /// assert!(!f.is_sign_negative());
     /// assert!(g.is_sign_negative());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
diff --git a/library/core/src/num/f64.rs b/library/core/src/num/f64.rs
index cfcc08b9addeb..233c7b7e8de82 100644
--- a/library/core/src/num/f64.rs
+++ b/library/core/src/num/f64.rs
@@ -435,6 +435,7 @@ impl f64 {
     /// assert!(nan.is_nan());
     /// assert!(!f.is_nan());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -466,6 +467,7 @@ impl f64 {
     /// assert!(inf.is_infinite());
     /// assert!(neg_inf.is_infinite());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -487,6 +489,7 @@ impl f64 {
     /// assert!(!inf.is_finite());
     /// assert!(!neg_inf.is_finite());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -514,6 +517,7 @@ impl f64 {
     /// assert!(lower_than_min.is_subnormal());
     /// ```
     /// [subnormal]: https://en.wikipedia.org/wiki/Denormal_number
+    #[must_use]
     #[stable(feature = "is_subnormal", since = "1.53.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -540,6 +544,7 @@ impl f64 {
     /// assert!(!lower_than_min.is_normal());
     /// ```
     /// [subnormal]: https://en.wikipedia.org/wiki/Denormal_number
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -586,6 +591,7 @@ impl f64 {
     /// assert!(f.is_sign_positive());
     /// assert!(!g.is_sign_positive());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -593,6 +599,7 @@ impl f64 {
         !self.is_sign_negative()
     }
 
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_deprecated(since = "1.0.0", reason = "renamed to is_sign_positive")]
     #[inline]
@@ -611,6 +618,7 @@ impl f64 {
     /// assert!(!f.is_sign_negative());
     /// assert!(g.is_sign_negative());
     /// ```
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_unstable(feature = "const_float_classify", issue = "72505")]
     #[inline]
@@ -618,6 +626,7 @@ impl f64 {
         self.to_bits() & 0x8000_0000_0000_0000 != 0
     }
 
+    #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_deprecated(since = "1.0.0", reason = "renamed to is_sign_negative")]
     #[inline]
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index 12dda61400f2a..1eff6f9613019 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -2199,7 +2199,8 @@ macro_rules! int_impl {
             }
         }
 
-        /// Returns the logarithm of the number with respect to an arbitrary base.
+        /// Returns the logarithm of the number with respect to an arbitrary base,
+        /// rounded down.
         ///
         /// This method might not be optimized owing to implementation details;
         /// `log2` can produce results more efficiently for base 2, and `log10`
@@ -2208,8 +2209,8 @@ macro_rules! int_impl {
         /// # Panics
         ///
         /// When the number is zero, or if the base is not at least 2; it
-        /// panics in debug mode and the return value is wrapped to 0 in release
-        /// mode (the only situation in which the method can return 0).
+        /// panics in debug mode and the return value is 0 in release
+        /// mode.
         ///
         /// # Examples
         ///
@@ -2237,13 +2238,12 @@ macro_rules! int_impl {
             }
         }
 
-        /// Returns the base 2 logarithm of the number.
+        /// Returns the base 2 logarithm of the number, rounded down.
         ///
         /// # Panics
         ///
         /// When the number is zero it panics in debug mode and the return value
-        /// is wrapped to 0 in release mode (the only situation in which the
-        /// method can return 0).
+        /// is 0 in release mode.
         ///
         /// # Examples
         ///
@@ -2271,13 +2271,12 @@ macro_rules! int_impl {
             }
         }
 
-        /// Returns the base 10 logarithm of the number.
+        /// Returns the base 10 logarithm of the number, rounded down.
         ///
         /// # Panics
         ///
         /// When the number is zero it panics in debug mode and the return value
-        /// is wrapped to 0 in release mode (the only situation in which the
-        /// method can return 0).
+        /// is 0 in release mode.
         ///
         /// # Example
         ///
@@ -2305,7 +2304,8 @@ macro_rules! int_impl {
             }
         }
 
-        /// Returns the logarithm of the number with respect to an arbitrary base.
+        /// Returns the logarithm of the number with respect to an arbitrary base,
+        /// rounded down.
         ///
         /// Returns `None` if the number is negative or zero, or if the base is not at least 2.
         ///
@@ -2345,7 +2345,7 @@ macro_rules! int_impl {
             }
         }
 
-        /// Returns the base 2 logarithm of the number.
+        /// Returns the base 2 logarithm of the number, rounded down.
         ///
         /// Returns `None` if the number is negative or zero.
         ///
@@ -2369,7 +2369,7 @@ macro_rules! int_impl {
             }
         }
 
-        /// Returns the base 10 logarithm of the number.
+        /// Returns the base 10 logarithm of the number, rounded down.
         ///
         /// Returns `None` if the number is negative or zero.
         ///
@@ -2502,6 +2502,7 @@ macro_rules! int_impl {
         #[doc = concat!("assert!(10", stringify!($SelfT), ".is_positive());")]
         #[doc = concat!("assert!(!(-10", stringify!($SelfT), ").is_positive());")]
         /// ```
+        #[must_use]
         #[stable(feature = "rust1", since = "1.0.0")]
         #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
         #[inline(always)]
@@ -2518,6 +2519,7 @@ macro_rules! int_impl {
         #[doc = concat!("assert!((-10", stringify!($SelfT), ").is_negative());")]
         #[doc = concat!("assert!(!10", stringify!($SelfT), ".is_negative());")]
         /// ```
+        #[must_use]
         #[stable(feature = "rust1", since = "1.0.0")]
         #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")]
         #[inline(always)]
diff --git a/library/core/src/num/mod.rs b/library/core/src/num/mod.rs
index 44918a711d470..18ebf1cbb1063 100644
--- a/library/core/src/num/mod.rs
+++ b/library/core/src/num/mod.rs
@@ -259,6 +259,7 @@ impl u8 {
     /// assert!(ascii.is_ascii());
     /// assert!(!non_ascii.is_ascii());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")]
     #[rustc_const_stable(feature = "const_ascii_methods_on_intrinsics", since = "1.43.0")]
     #[inline]
@@ -419,6 +420,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_alphabetic());
     /// assert!(!esc.is_ascii_alphabetic());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -452,6 +454,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_uppercase());
     /// assert!(!esc.is_ascii_uppercase());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -485,6 +488,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_lowercase());
     /// assert!(!esc.is_ascii_lowercase());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -521,6 +525,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_alphanumeric());
     /// assert!(!esc.is_ascii_alphanumeric());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -554,6 +559,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_digit());
     /// assert!(!esc.is_ascii_digit());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -590,6 +596,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_hexdigit());
     /// assert!(!esc.is_ascii_hexdigit());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -627,6 +634,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_punctuation());
     /// assert!(!esc.is_ascii_punctuation());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -660,6 +668,7 @@ impl u8 {
     /// assert!(!lf.is_ascii_graphic());
     /// assert!(!esc.is_ascii_graphic());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -710,6 +719,7 @@ impl u8 {
     /// assert!(lf.is_ascii_whitespace());
     /// assert!(!esc.is_ascii_whitespace());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
@@ -745,6 +755,7 @@ impl u8 {
     /// assert!(lf.is_ascii_control());
     /// assert!(esc.is_ascii_control());
     /// ```
+    #[must_use]
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
     #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs
index e44597279baf2..c1e768655e094 100644
--- a/library/core/src/num/nonzero.rs
+++ b/library/core/src/num/nonzero.rs
@@ -878,6 +878,7 @@ macro_rules! nonzero_unsigned_is_power_of_two {
                 #[doc = concat!("let ten = std::num::", stringify!($Ty), "::new(10).unwrap();")]
                 /// assert!(!ten.is_power_of_two());
                 /// ```
+                #[must_use]
                 #[unstable(feature = "nonzero_is_power_of_two", issue = "81106")]
                 #[inline]
                 pub const fn is_power_of_two(self) -> bool {
diff --git a/library/core/src/num/saturating.rs b/library/core/src/num/saturating.rs
index f6dd3603c4914..af7b9c63fd207 100644
--- a/library/core/src/num/saturating.rs
+++ b/library/core/src/num/saturating.rs
@@ -847,6 +847,7 @@ macro_rules! saturating_int_impl_signed {
             #[doc = concat!("assert!(Saturating(10", stringify!($t), ").is_positive());")]
             #[doc = concat!("assert!(!Saturating(-10", stringify!($t), ").is_positive());")]
             /// ```
+            #[must_use]
             #[inline]
             #[unstable(feature = "saturating_int_impl", issue = "87920")]
             pub const fn is_positive(self) -> bool {
@@ -867,6 +868,7 @@ macro_rules! saturating_int_impl_signed {
             #[doc = concat!("assert!(Saturating(-10", stringify!($t), ").is_negative());")]
             #[doc = concat!("assert!(!Saturating(10", stringify!($t), ").is_negative());")]
             /// ```
+            #[must_use]
             #[inline]
             #[unstable(feature = "saturating_int_impl", issue = "87920")]
             pub const fn is_negative(self) -> bool {
@@ -925,6 +927,7 @@ macro_rules! saturating_int_impl_unsigned {
             #[doc = concat!("assert!(Saturating(16", stringify!($t), ").is_power_of_two());")]
             #[doc = concat!("assert!(!Saturating(10", stringify!($t), ").is_power_of_two());")]
             /// ```
+            #[must_use]
             #[inline]
             #[unstable(feature = "saturating_int_impl", issue = "87920")]
             pub fn is_power_of_two(self) -> bool {
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 25cd582bb67d7..8cd5b2c6dc0c1 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -658,7 +658,8 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Returns the logarithm of the number with respect to an arbitrary base.
+        /// Returns the logarithm of the number with respect to an arbitrary base,
+        /// rounded down.
         ///
         /// This method might not be optimized owing to implementation details;
         /// `log2` can produce results more efficiently for base 2, and `log10`
@@ -667,8 +668,7 @@ macro_rules! uint_impl {
         /// # Panics
         ///
         /// When the number is negative, zero, or if the base is not at least 2;
-        /// it panics in debug mode and the return value is wrapped to 0 in
-        /// release mode (the only situation in which the method can return 0).
+        /// it panics in debug mode and the return value is 0 in release mode.
         ///
         /// # Examples
         ///
@@ -696,13 +696,12 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Returns the base 2 logarithm of the number.
+        /// Returns the base 2 logarithm of the number, rounded down.
         ///
         /// # Panics
         ///
         /// When the number is negative or zero it panics in debug mode and
-        /// the return value is wrapped to 0 in release mode (the only situation in
-        /// which the method can return 0).
+        /// the return value is 0 in release mode.
         ///
         /// # Examples
         ///
@@ -730,13 +729,12 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Returns the base 10 logarithm of the number.
+        /// Returns the base 10 logarithm of the number, rounded down.
         ///
         /// # Panics
         ///
         /// When the number is negative or zero it panics in debug mode and the
-        /// return value is wrapped to 0 in release mode (the only situation in
-        /// which the method can return 0).
+        /// return value is 0 in release mode.
         ///
         /// # Example
         ///
@@ -764,7 +762,8 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Returns the logarithm of the number with respect to an arbitrary base.
+        /// Returns the logarithm of the number with respect to an arbitrary base,
+        /// rounded down.
         ///
         /// Returns `None` if the number is zero, or if the base is not at least 2.
         ///
@@ -804,7 +803,7 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Returns the base 2 logarithm of the number.
+        /// Returns the base 2 logarithm of the number, rounded down.
         ///
         /// Returns `None` if the number is zero.
         ///
@@ -828,7 +827,7 @@ macro_rules! uint_impl {
             }
         }
 
-        /// Returns the base 10 logarithm of the number.
+        /// Returns the base 10 logarithm of the number, rounded down.
         ///
         /// Returns `None` if the number is zero.
         ///
@@ -2087,6 +2086,7 @@ macro_rules! uint_impl {
         #[doc = concat!("assert!(16", stringify!($SelfT), ".is_power_of_two());")]
         #[doc = concat!("assert!(!10", stringify!($SelfT), ".is_power_of_two());")]
         /// ```
+        #[must_use]
         #[stable(feature = "rust1", since = "1.0.0")]
         #[rustc_const_stable(feature = "const_is_power_of_two", since = "1.32.0")]
         #[inline(always)]
@@ -2120,7 +2120,7 @@ macro_rules! uint_impl {
         /// Returns the smallest power of two greater than or equal to `self`.
         ///
         /// When return value overflows (i.e., `self > (1 << (N-1))` for type
-        /// `uN`), it panics in debug mode and return value is wrapped to 0 in
+        /// `uN`), it panics in debug mode and the return value is wrapped to 0 in
         /// release mode (the only situation in which method can return 0).
         ///
         /// # Examples
diff --git a/library/core/src/num/wrapping.rs b/library/core/src/num/wrapping.rs
index b078cdf5479d7..beb413bbddca4 100644
--- a/library/core/src/num/wrapping.rs
+++ b/library/core/src/num/wrapping.rs
@@ -844,6 +844,7 @@ macro_rules! wrapping_int_impl_signed {
             #[doc = concat!("assert!(Wrapping(10", stringify!($t), ").is_positive());")]
             #[doc = concat!("assert!(!Wrapping(-10", stringify!($t), ").is_positive());")]
             /// ```
+            #[must_use]
             #[inline]
             #[unstable(feature = "wrapping_int_impl", issue = "32463")]
             pub const fn is_positive(self) -> bool {
@@ -864,6 +865,7 @@ macro_rules! wrapping_int_impl_signed {
             #[doc = concat!("assert!(Wrapping(-10", stringify!($t), ").is_negative());")]
             #[doc = concat!("assert!(!Wrapping(10", stringify!($t), ").is_negative());")]
             /// ```
+            #[must_use]
             #[inline]
             #[unstable(feature = "wrapping_int_impl", issue = "32463")]
             pub const fn is_negative(self) -> bool {
@@ -911,6 +913,7 @@ macro_rules! wrapping_int_impl_unsigned {
             #[doc = concat!("assert!(Wrapping(16", stringify!($t), ").is_power_of_two());")]
             #[doc = concat!("assert!(!Wrapping(10", stringify!($t), ").is_power_of_two());")]
             /// ```
+            #[must_use]
             #[inline]
             #[unstable(feature = "wrapping_int_impl", issue = "32463")]
             pub fn is_power_of_two(self) -> bool {
diff --git a/library/core/src/str/mod.rs b/library/core/src/str/mod.rs
index f25ab52cfa0d0..b5d151e479f8d 100644
--- a/library/core/src/str/mod.rs
+++ b/library/core/src/str/mod.rs
@@ -188,6 +188,7 @@ impl str {
     /// // third byte of `老`
     /// assert!(!s.is_char_boundary(8));
     /// ```
+    #[must_use]
     #[stable(feature = "is_char_boundary", since = "1.9.0")]
     #[inline]
     pub fn is_char_boundary(&self, index: usize) -> bool {
diff --git a/library/core/src/time.rs b/library/core/src/time.rs
index d1533b8d67a6b..949a3e68f2b6a 100644
--- a/library/core/src/time.rs
+++ b/library/core/src/time.rs
@@ -291,6 +291,7 @@ impl Duration {
     /// assert!(!Duration::from_nanos(1).is_zero());
     /// assert!(!Duration::from_secs(1).is_zero());
     /// ```
+    #[must_use]
     #[stable(feature = "duration_zero", since = "1.53.0")]
     #[rustc_const_stable(feature = "duration_zero", since = "1.53.0")]
     #[inline]
diff --git a/src/bootstrap/test.rs b/src/bootstrap/test.rs
index 68fbbb22c0898..8594fa42266b4 100644
--- a/src/bootstrap/test.rs
+++ b/src/bootstrap/test.rs
@@ -898,7 +898,7 @@ impl Step for RustdocGUI {
         let out_dir = builder.test_out(self.target).join("rustdoc-gui");
 
         // We remove existing folder to be sure there won't be artifacts remaining.
-        let _ = fs::remove_dir_all(&out_dir);
+        builder.clear_if_dirty(&out_dir, &builder.rustdoc(self.compiler));
 
         let src_path = builder.build.src.join("src/test/rustdoc-gui/src");
         // We generate docs for the libraries present in the rustdoc-gui's src folder.
diff --git a/src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs b/src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs
new file mode 100644
index 0000000000000..2a34ed4d4f644
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs
@@ -0,0 +1,31 @@
+#![deny(non_exhaustive_omitted_patterns)]
+//~^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+//~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+#![allow(non_exhaustive_omitted_patterns)]
+//~^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+//~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+
+fn main() {
+    enum Foo {
+        A, B, C,
+    }
+
+    #[allow(non_exhaustive_omitted_patterns)]
+    match Foo::A {
+        Foo::A => {}
+        Foo::B => {}
+    }
+    //~^^^^^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+
+    match Foo::A {
+        Foo::A => {}
+        Foo::B => {}
+        #[warn(non_exhaustive_omitted_patterns)]
+        _ => {}
+    }
+    //~^^^ ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+    //~| ERROR the `non_exhaustive_omitted_patterns` lint is unstable
+}
diff --git a/src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr b/src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr
new file mode 100644
index 0000000000000..691f64cf0addd
--- /dev/null
+++ b/src/test/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr
@@ -0,0 +1,93 @@
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:1:1
+   |
+LL | #![deny(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:4:1
+   |
+LL | #![allow(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:26:9
+   |
+LL |         #[warn(non_exhaustive_omitted_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:1:1
+   |
+LL | #![deny(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:4:1
+   |
+LL | #![allow(non_exhaustive_omitted_patterns)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:5
+   |
+LL |     #[allow(non_exhaustive_omitted_patterns)]
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error[E0658]: the `non_exhaustive_omitted_patterns` lint is unstable
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:26:9
+   |
+LL |         #[warn(non_exhaustive_omitted_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
+   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
+
+error: aborting due to 10 previous errors
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.rs b/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.rs
index c196ded404ddc..ce1b5c7c377a4 100644
--- a/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.rs
+++ b/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.rs
@@ -1,5 +1,7 @@
 // Test that the `non_exhaustive_omitted_patterns` lint is triggered correctly.
 
+#![feature(non_exhaustive_omitted_patterns_lint)]
+
 // aux-build:enums.rs
 extern crate enums;
 
diff --git a/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.stderr b/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.stderr
index e66fd8008a10b..5b21e0402b192 100644
--- a/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.stderr
+++ b/src/test/ui/rfc-2008-non-exhaustive/reachable-patterns.stderr
@@ -1,11 +1,11 @@
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:127:9
+  --> $DIR/reachable-patterns.rs:129:9
    |
 LL |         VariantNonExhaustive::Bar { x, .. } => {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `y` not listed
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:124:12
+  --> $DIR/reachable-patterns.rs:126:12
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -13,13 +13,13 @@ LL |     #[warn(non_exhaustive_omitted_patterns)]
    = note: the pattern is of type `VariantNonExhaustive` and the `non_exhaustive_omitted_patterns` attribute was found
 
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:132:9
+  --> $DIR/reachable-patterns.rs:134:9
    |
 LL |     let FunctionalRecord { first_field, second_field, .. } = FunctionalRecord::default();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `third_field` not listed
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:131:12
+  --> $DIR/reachable-patterns.rs:133:12
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -27,13 +27,13 @@ LL |     #[warn(non_exhaustive_omitted_patterns)]
    = note: the pattern is of type `FunctionalRecord` and the `non_exhaustive_omitted_patterns` attribute was found
 
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:140:29
+  --> $DIR/reachable-patterns.rs:142:29
    |
 LL |     let NestedStruct { bar: NormalStruct { first_field, .. }, .. } = NestedStruct::default();
    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `second_field` not listed
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:139:12
+  --> $DIR/reachable-patterns.rs:141:12
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -41,7 +41,7 @@ LL |     #[warn(non_exhaustive_omitted_patterns)]
    = note: the pattern is of type `NormalStruct` and the `non_exhaustive_omitted_patterns` attribute was found
 
 warning: some fields are not explicitly listed
-  --> $DIR/reachable-patterns.rs:140:9
+  --> $DIR/reachable-patterns.rs:142:9
    |
 LL |     let NestedStruct { bar: NormalStruct { first_field, .. }, .. } = NestedStruct::default();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ field `foo` not listed
@@ -50,13 +50,13 @@ LL |     let NestedStruct { bar: NormalStruct { first_field, .. }, .. } = Nested
    = note: the pattern is of type `NestedStruct` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:54:9
+  --> $DIR/reachable-patterns.rs:56:9
    |
 LL |         _ => {}
    |         ^ pattern `Struct { .. }` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:53:16
+  --> $DIR/reachable-patterns.rs:55:16
    |
 LL |         #[deny(non_exhaustive_omitted_patterns)]
    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -64,13 +64,13 @@ LL |         #[deny(non_exhaustive_omitted_patterns)]
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:61:9
+  --> $DIR/reachable-patterns.rs:63:9
    |
 LL |         _ => {}
    |         ^ pattern `Tuple(_)` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:60:16
+  --> $DIR/reachable-patterns.rs:62:16
    |
 LL |         #[deny(non_exhaustive_omitted_patterns)]
    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -78,13 +78,13 @@ LL |         #[deny(non_exhaustive_omitted_patterns)]
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:71:9
+  --> $DIR/reachable-patterns.rs:73:9
    |
 LL |         _ => {}
    |         ^ pattern `Unit` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:70:16
+  --> $DIR/reachable-patterns.rs:72:16
    |
 LL |         #[deny(non_exhaustive_omitted_patterns)]
    |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -92,13 +92,13 @@ LL |         #[deny(non_exhaustive_omitted_patterns)]
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:88:32
+  --> $DIR/reachable-patterns.rs:90:32
    |
 LL |         NestedNonExhaustive::A(_) => {}
    |                                ^ patterns `Tuple(_)` and `Struct { .. }` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:85:12
+  --> $DIR/reachable-patterns.rs:87:12
    |
 LL |     #[deny(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -106,7 +106,7 @@ LL |     #[deny(non_exhaustive_omitted_patterns)]
    = note: the matched value is of type `NonExhaustiveEnum` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:90:9
+  --> $DIR/reachable-patterns.rs:92:9
    |
 LL |         _ => {}
    |         ^ pattern `C` not covered
@@ -115,13 +115,13 @@ LL |         _ => {}
    = note: the matched value is of type `NestedNonExhaustive` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:120:9
+  --> $DIR/reachable-patterns.rs:122:9
    |
 LL |         _ => {}
    |         ^ patterns `HostUnreachable`, `NetworkUnreachable`, `NetworkDown` and 18 more not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:97:12
+  --> $DIR/reachable-patterns.rs:99:12
    |
 LL |     #[deny(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -129,13 +129,13 @@ LL |     #[deny(non_exhaustive_omitted_patterns)]
    = note: the matched value is of type `ErrorKind` and the `non_exhaustive_omitted_patterns` attribute was found
 
 error: some variants are not matched explicitly
-  --> $DIR/reachable-patterns.rs:157:9
+  --> $DIR/reachable-patterns.rs:159:9
    |
 LL |         _ => {}
    |         ^ pattern `A(_)` not covered
    |
 note: the lint level is defined here
-  --> $DIR/reachable-patterns.rs:155:12
+  --> $DIR/reachable-patterns.rs:157:12
    |
 LL |     #[deny(non_exhaustive_omitted_patterns)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/wasm/simd-to-array-80108.rs b/src/test/ui/wasm/simd-to-array-80108.rs
new file mode 100644
index 0000000000000..4e44cd01f286e
--- /dev/null
+++ b/src/test/ui/wasm/simd-to-array-80108.rs
@@ -0,0 +1,15 @@
+// only-wasm32
+// build-pass
+#![feature(repr_simd)]
+
+// Regression test for #80108
+
+
+#[repr(simd)]
+pub struct Vector([i32; 4]);
+
+impl Vector {
+    pub const fn to_array(self) -> [i32; 4] {
+        self.0
+    }
+}