Rollup of 7 pull requests

Cargo.lock

@@ -5321,6 +5321,7 @@ version = "0.0.0"
 dependencies = [
  "core",
  "getopts",
+ "libc",
  "panic_abort",
  "panic_unwind",
  "std",

compiler/rustc_hir_typeck/src/method/suggest.rs

@@ -554,6 +554,17 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     "`count` is defined on `{iterator_trait}`, which `{rcvr_ty}` does not implement"
                 ));
             }
+        } else if !unsatisfied_predicates.is_empty() && matches!(rcvr_ty.kind(), ty::Param(_)) {
+            // We special case the situation where we are looking for `_` in
+            // `<TypeParam as _>::method` because otherwise the machinery will look for blanket
+            // implementations that have unsatisfied trait bounds to suggest, leading us to claim
+            // things like "we're looking for a trait with method `cmp`, both `Iterator` and `Ord`
+            // have one, in order to implement `Ord` you need to restrict `TypeParam: FnPtr` so
+            // that `impl<T: FnPtr> Ord for T` can apply", which is not what we want. We have a type
+            // parameter, we want to directly say "`Ord::cmp` and `Iterator::cmp` exist, restrict
+            // `TypeParam: Ord` or `TypeParam: Iterator`"". That is done further down when calling
+            // `self.suggest_traits_to_import`, so we ignore the `unsatisfied_predicates`
+            // suggestions.
         } else if !unsatisfied_predicates.is_empty() {
             let mut type_params = FxIndexMap::default();
 
@@ -1325,7 +1336,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             }
         }
         self.note_derefed_ty_has_method(&mut err, source, rcvr_ty, item_name, expected);
-        return Some(err);
+        Some(err)
     }
 
     fn note_candidates_on_method_error(
@@ -2918,19 +2929,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // this isn't perfect (that is, there are cases when
                 // implementing a trait would be legal but is rejected
                 // here).
-                unsatisfied_predicates.iter().all(|(p, _, _)| {
-                    match p.kind().skip_binder() {
-                        // Hide traits if they are present in predicates as they can be fixed without
-                        // having to implement them.
-                        ty::PredicateKind::Clause(ty::ClauseKind::Trait(t)) => {
-                            t.def_id() == info.def_id
-                        }
-                        ty::PredicateKind::Clause(ty::ClauseKind::Projection(p)) => {
-                            p.projection_ty.def_id == info.def_id
-                        }
-                        _ => false,
-                    }
-                }) && (type_is_local || info.def_id.is_local())
+                (type_is_local || info.def_id.is_local())
                     && !self.tcx.trait_is_auto(info.def_id)
                     && self
                         .associated_value(info.def_id, item_name)
@@ -2978,6 +2977,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             item.visibility(self.tcx).is_public() || info.def_id.is_local()
                         })
                         .is_some()
+                    && (matches!(rcvr_ty.kind(), ty::Param(_))
+                        || unsatisfied_predicates.iter().all(|(p, _, _)| {
+                            match p.kind().skip_binder() {
+                                // Hide traits if they are present in predicates as they can be fixed without
+                                // having to implement them.
+                                ty::PredicateKind::Clause(ty::ClauseKind::Trait(t)) => {
+                                    t.def_id() == info.def_id
+                                }
+                                ty::PredicateKind::Clause(ty::ClauseKind::Projection(p)) => {
+                                    p.projection_ty.def_id == info.def_id
+                                }
+                                _ => false,
+                            }
+                        }))
             })
             .collect::<Vec<_>>();
         for span in &arbitrary_rcvr {

compiler/rustc_lint/src/context/diagnostics.rs

@@ -188,6 +188,23 @@ pub(super) fn builtin(
             #[allow(rustc::potential_query_instability)]
             let possibilities: Vec<Symbol> =
                 sess.parse_sess.check_config.expecteds.keys().copied().collect();
+
+            let mut names_possibilities: Vec<_> = if value.is_none() {
+                // We later sort and display all the possibilities, so the order here does not matter.
+                #[allow(rustc::potential_query_instability)]
+                sess.parse_sess
+                    .check_config
+                    .expecteds
+                    .iter()
+                    .filter_map(|(k, v)| match v {
+                        ExpectedValues::Some(v) if v.contains(&Some(name)) => Some(k),
+                        _ => None,
+                    })
+                    .collect()
+            } else {
+                Vec::new()
+            };
+
             let is_from_cargo = std::env::var_os("CARGO").is_some();
             let mut is_feature_cfg = name == sym::feature;
 
@@ -262,17 +279,30 @@ pub(super) fn builtin(
                 }
 
                 is_feature_cfg |= best_match == sym::feature;
-            } else if !possibilities.is_empty() {
-                let mut possibilities =
-                    possibilities.iter().map(Symbol::as_str).collect::<Vec<_>>();
-                possibilities.sort();
-                let possibilities = possibilities.join("`, `");
+            } else {
+                if !names_possibilities.is_empty() && names_possibilities.len() <= 3 {
+                    names_possibilities.sort();
+                    for cfg_name in names_possibilities.iter() {
+                        db.span_suggestion(
+                            name_span,
+                            "found config with similar value",
+                            format!("{cfg_name} = \"{name}\""),
+                            Applicability::MaybeIncorrect,
+                        );
+                    }
+                }
+                if !possibilities.is_empty() {
+                    let mut possibilities =
+                        possibilities.iter().map(Symbol::as_str).collect::<Vec<_>>();
+                    possibilities.sort();
+                    let possibilities = possibilities.join("`, `");
 
-                // The list of expected names can be long (even by default) and
-                // so the diagnostic produced can take a lot of space. To avoid
-                // cloging the user output we only want to print that diagnostic
-                // once.
-                db.help_once(format!("expected names are: `{possibilities}`"));
+                    // The list of expected names can be long (even by default) and
+                    // so the diagnostic produced can take a lot of space. To avoid
+                    // cloging the user output we only want to print that diagnostic
+                    // once.
+                    db.help_once(format!("expected names are: `{possibilities}`"));
+                }
             }
 
             let inst = if let Some((value, _value_span)) = value {

compiler/rustc_lint/src/lib.rs

@@ -516,6 +516,10 @@ fn register_builtins(store: &mut LintStore) {
         "converted into hard error, see PR #118649 \
          <https://github.com/rust-lang/rust/pull/118649> for more information",
     );
+    store.register_removed(
+        "illegal_floating_point_literal_pattern",
+        "no longer a warning, float patterns behave the same as `==`",
+    );
 }
 
 fn register_internals(store: &mut LintStore) {

compiler/rustc_lint_defs/src/builtin.rs

@@ -45,7 +45,6 @@ declare_lint_pass! {
         FUZZY_PROVENANCE_CASTS,
         HIDDEN_GLOB_REEXPORTS,
         ILL_FORMED_ATTRIBUTE_INPUT,
-        ILLEGAL_FLOATING_POINT_LITERAL_PATTERN,
         INCOMPLETE_INCLUDE,
         INDIRECT_STRUCTURAL_MATCH,
         INEFFECTIVE_UNSTABLE_TRAIT_IMPL,
@@ -1873,55 +1872,6 @@ declare_lint! {
      };
 }
 
-declare_lint! {
-    /// The `illegal_floating_point_literal_pattern` lint detects
-    /// floating-point literals used in patterns.
-    ///
-    /// ### Example
-    ///
-    /// ```rust
-    /// let x = 42.0;
-    ///
-    /// match x {
-    ///     5.0 => {}
-    ///     _ => {}
-    /// }
-    /// ```
-    ///
-    /// {{produces}}
-    ///
-    /// ### Explanation
-    ///
-    /// Previous versions of the compiler accepted floating-point literals in
-    /// patterns, but it was later determined this was a mistake. The
-    /// semantics of comparing floating-point values may not be clear in a
-    /// pattern when contrasted with "structural equality". Typically you can
-    /// work around this by using a [match guard], such as:
-    ///
-    /// ```rust
-    /// # let x = 42.0;
-    ///
-    /// match x {
-    ///     y if y == 5.0 => {}
-    ///     _ => {}
-    /// }
-    /// ```
-    ///
-    /// This is a [future-incompatible] lint to transition this to a hard
-    /// error in the future. See [issue #41620] for more details.
-    ///
-    /// [issue #41620]: https://github.com/rust-lang/rust/issues/41620
-    /// [match guard]: https://doc.rust-lang.org/reference/expressions/match-expr.html#match-guards
-    /// [future-incompatible]: ../index.md#future-incompatible-lints
-    pub ILLEGAL_FLOATING_POINT_LITERAL_PATTERN,
-    Warn,
-    "floating-point literals cannot be used in patterns",
-    @future_incompatible = FutureIncompatibleInfo {
-        reason: FutureIncompatibilityReason::FutureReleaseErrorDontReportInDeps,
-        reference: "issue #41620 <https://github.com/rust-lang/rust/issues/41620>",
-    };
-}
-
 declare_lint! {
     /// The `unstable_name_collisions` lint detects that you have used a name
     /// that the standard library plans to add in the future.

compiler/rustc_middle/src/mir/interpret/value.rs

@@ -418,8 +418,8 @@ impl<'tcx, Prov: Provenance> Scalar<Prov> {
 
     #[inline]
     pub fn to_float<F: Float>(self) -> InterpResult<'tcx, F> {
-        // Going through `to_uint` to check size and truncation.
-        Ok(F::from_bits(self.to_uint(Size::from_bits(F::BITS))?))
+        // Going through `to_bits` to check size and truncation.
+        Ok(F::from_bits(self.to_bits(Size::from_bits(F::BITS))?))
     }
 
     #[inline]

compiler/rustc_middle/src/ty/consts/int.rs

@@ -249,11 +249,6 @@ impl ScalarInt {
         }
     }
 
-    #[inline]
-    pub fn try_to_target_usize(&self, tcx: TyCtxt<'_>) -> Result<u64, Size> {
-        Ok(self.to_bits(tcx.data_layout.pointer_size)? as u64)
-    }
-
     /// Tries to convert the `ScalarInt` to an unsigned integer of the given size.
     /// Fails if the size of the `ScalarInt` is not equal to `size` and returns the
     /// `ScalarInt`s size in that case.
@@ -262,56 +257,61 @@ impl ScalarInt {
         self.to_bits(size)
     }
 
-    // Tries to convert the `ScalarInt` to `bool`. Fails if the `size` of the `ScalarInt`
-    // in not equal to `Size { raw: 1 }` or if the value is not 0 or 1 and returns the `size`
-    // value of the `ScalarInt` in that case.
-    #[inline]
-    pub fn try_to_bool(self) -> Result<bool, Size> {
-        match self.try_to_u8()? {
-            0 => Ok(false),
-            1 => Ok(true),
-            _ => Err(self.size()),
-        }
-    }
-
     // Tries to convert the `ScalarInt` to `u8`. Fails if the `size` of the `ScalarInt`
     // in not equal to `Size { raw: 1 }` and returns the `size` value of the `ScalarInt` in
     // that case.
     #[inline]
     pub fn try_to_u8(self) -> Result<u8, Size> {
-        self.to_bits(Size::from_bits(8)).map(|v| u8::try_from(v).unwrap())
+        self.try_to_uint(Size::from_bits(8)).map(|v| u8::try_from(v).unwrap())
     }
 
     /// Tries to convert the `ScalarInt` to `u16`. Fails if the size of the `ScalarInt`
     /// in not equal to `Size { raw: 2 }` and returns the `size` value of the `ScalarInt` in
     /// that case.
     #[inline]
     pub fn try_to_u16(self) -> Result<u16, Size> {
-        self.to_bits(Size::from_bits(16)).map(|v| u16::try_from(v).unwrap())
+        self.try_to_uint(Size::from_bits(16)).map(|v| u16::try_from(v).unwrap())
     }
 
     /// Tries to convert the `ScalarInt` to `u32`. Fails if the `size` of the `ScalarInt`
     /// in not equal to `Size { raw: 4 }` and returns the `size` value of the `ScalarInt` in
     /// that case.
     #[inline]
     pub fn try_to_u32(self) -> Result<u32, Size> {
-        self.to_bits(Size::from_bits(32)).map(|v| u32::try_from(v).unwrap())
+        self.try_to_uint(Size::from_bits(32)).map(|v| u32::try_from(v).unwrap())
     }
 
     /// Tries to convert the `ScalarInt` to `u64`. Fails if the `size` of the `ScalarInt`
     /// in not equal to `Size { raw: 8 }` and returns the `size` value of the `ScalarInt` in
     /// that case.
     #[inline]
     pub fn try_to_u64(self) -> Result<u64, Size> {
-        self.to_bits(Size::from_bits(64)).map(|v| u64::try_from(v).unwrap())
+        self.try_to_uint(Size::from_bits(64)).map(|v| u64::try_from(v).unwrap())
     }
 
     /// Tries to convert the `ScalarInt` to `u128`. Fails if the `size` of the `ScalarInt`
     /// in not equal to `Size { raw: 16 }` and returns the `size` value of the `ScalarInt` in
     /// that case.
     #[inline]
     pub fn try_to_u128(self) -> Result<u128, Size> {
-        self.to_bits(Size::from_bits(128))
+        self.try_to_uint(Size::from_bits(128))
+    }
+
+    #[inline]
+    pub fn try_to_target_usize(&self, tcx: TyCtxt<'_>) -> Result<u64, Size> {
+        self.try_to_uint(tcx.data_layout.pointer_size).map(|v| u64::try_from(v).unwrap())
+    }
+
+    // Tries to convert the `ScalarInt` to `bool`. Fails if the `size` of the `ScalarInt`
+    // in not equal to `Size { raw: 1 }` or if the value is not 0 or 1 and returns the `size`
+    // value of the `ScalarInt` in that case.
+    #[inline]
+    pub fn try_to_bool(self) -> Result<bool, Size> {
+        match self.try_to_u8()? {
+            0 => Ok(false),
+            1 => Ok(true),
+            _ => Err(self.size()),
+        }
     }
 
     /// Tries to convert the `ScalarInt` to a signed integer of the given size.
@@ -357,6 +357,27 @@ impl ScalarInt {
     pub fn try_to_i128(self) -> Result<i128, Size> {
         self.try_to_int(Size::from_bits(128))
     }
+
+    #[inline]
+    pub fn try_to_target_isize(&self, tcx: TyCtxt<'_>) -> Result<i64, Size> {
+        self.try_to_int(tcx.data_layout.pointer_size).map(|v| i64::try_from(v).unwrap())
+    }
+
+    #[inline]
+    pub fn try_to_float<F: Float>(self) -> Result<F, Size> {
+        // Going through `to_uint` to check size and truncation.
+        Ok(F::from_bits(self.to_bits(Size::from_bits(F::BITS))?))
+    }
+
+    #[inline]
+    pub fn try_to_f32(self) -> Result<Single, Size> {
+        self.try_to_float()
+    }
+
+    #[inline]
+    pub fn try_to_f64(self) -> Result<Double, Size> {
+        self.try_to_float()
+    }
 }
 
 macro_rules! from {
@@ -399,11 +420,7 @@ impl TryFrom<ScalarInt> for bool {
     type Error = Size;
     #[inline]
     fn try_from(int: ScalarInt) -> Result<Self, Size> {
-        int.to_bits(Size::from_bytes(1)).and_then(|u| match u {
-            0 => Ok(false),
-            1 => Ok(true),
-            _ => Err(Size::from_bytes(1)),
-        })
+        int.try_to_bool()
     }
 }
 

compiler/rustc_middle/src/ty/diagnostics.rs

@@ -98,6 +98,7 @@ impl<'tcx, T> IsSuggestable<'tcx> for T
 where
     T: TypeVisitable<TyCtxt<'tcx>> + TypeFoldable<TyCtxt<'tcx>>,
 {
+    #[tracing::instrument(level = "debug", skip(tcx))]
     fn is_suggestable(self, tcx: TyCtxt<'tcx>, infer_suggestable: bool) -> bool {
         self.visit_with(&mut IsSuggestableVisitor { tcx, infer_suggestable }).is_continue()
     }
@@ -533,6 +534,9 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for IsSuggestableVisitor<'tcx> {
         match c.kind() {
             ConstKind::Infer(InferConst::Var(_)) if self.infer_suggestable => {}
 
+            // effect variables are always suggestable, because they are not visible
+            ConstKind::Infer(InferConst::EffectVar(_)) => {}
+
             ConstKind::Infer(..)
             | ConstKind::Bound(..)
             | ConstKind::Placeholder(..)

compiler/rustc_mir_build/messages.ftl

@@ -107,8 +107,6 @@ mir_build_extern_static_requires_unsafe_unsafe_op_in_unsafe_fn_allowed =
     .note = extern statics are not controlled by the Rust type system: invalid data, aliasing violations or data races will cause undefined behavior
     .label = use of extern static
 
-mir_build_float_pattern = floating-point types cannot be used in patterns
-
 mir_build_indirect_structural_match =
     to use a constant of type `{$non_sm_ty}` in a pattern, `{$non_sm_ty}` must be annotated with `#[derive(PartialEq)]`
 
@@ -232,6 +230,10 @@ mir_build_mutation_of_layout_constrained_field_requires_unsafe_unsafe_op_in_unsa
     .note = mutating layout constrained fields cannot statically be checked for valid values
     .label = mutation of layout constrained field
 
+mir_build_nan_pattern = cannot use NaN in patterns
+    .note = NaNs compare inequal to everything, even themselves, so this pattern would never match
+    .help = try using the `is_nan` method instead
+
 mir_build_non_const_path = runtime values cannot be referenced in patterns
 
 mir_build_non_empty_never_pattern =