Rollup of 7 pull requests

compiler/rustc_builtin_macros/src/deriving/default.rs

@@ -46,18 +46,7 @@ pub fn expand_deriving_default(
                     StaticStruct(_, fields) => {
                         default_struct_substructure(cx, trait_span, substr, fields)
                     }
-                    StaticEnum(enum_def, _) => {
-                        if !cx.sess.features_untracked().derive_default_enum {
-                            rustc_session::parse::feature_err(
-                                cx.parse_sess(),
-                                sym::derive_default_enum,
-                                span,
-                                "deriving `Default` on enums is experimental",
-                            )
-                            .emit();
-                        }
-                        default_enum_substructure(cx, trait_span, enum_def)
-                    }
+                    StaticEnum(enum_def, _) => default_enum_substructure(cx, trait_span, enum_def),
                     _ => cx.span_bug(trait_span, "method in `derive(Default)`"),
                 }
             })),

compiler/rustc_errors/src/diagnostic.rs

@@ -832,7 +832,7 @@ impl Diagnostic {
         name: impl Into<Cow<'static, str>>,
         arg: DiagnosticArgValue<'static>,
     ) -> &mut Self {
-        self.args.push((name.into(), arg.into()));
+        self.args.push((name.into(), arg));
         self
     }
 

compiler/rustc_expand/src/mbe/macro_check.rs

@@ -270,7 +270,7 @@ fn check_binders(
                     MISSING_FRAGMENT_SPECIFIER,
                     span,
                     node_id,
-                    &format!("missing fragment specifier"),
+                    "missing fragment specifier",
                 );
             }
             if !macros.is_empty() {

compiler/rustc_feature/src/accepted.rs

@@ -126,6 +126,8 @@ declare_features! (
     (accepted, default_type_params, "1.0.0", None, None),
     /// Allows `#[deprecated]` attribute.
     (accepted, deprecated, "1.9.0", Some(29935), None),
+    /// Allows `#[derive(Default)]` and `#[default]` on enums.
+    (accepted, derive_default_enum, "1.62.0", Some(86985), None),
     /// Allows the use of destructuring assignments.
     (accepted, destructuring_assignment, "1.59.0", Some(71126), None),
     /// Allows `#[doc(alias = "...")]`.

compiler/rustc_feature/src/active.rs

@@ -368,8 +368,6 @@ declare_features! (
     (active, deprecated_safe, "1.61.0", Some(94978), None),
     /// Allows having using `suggestion` in the `#[deprecated]` attribute.
     (active, deprecated_suggestion, "1.61.0", Some(94785), None),
-    /// Allows `#[derive(Default)]` and `#[default]` on enums.
-    (active, derive_default_enum, "1.56.0", Some(86985), None),
     /// Tells rustdoc to automatically generate `#[doc(cfg(...))]`.
     (active, doc_auto_cfg, "1.58.0", Some(43781), None),
     /// Allows `#[doc(cfg(...))]`.

compiler/rustc_feature/src/lib.rs

@@ -11,7 +11,7 @@
 //! even if it is stabilized or removed, *do not remove it*. Instead, move the
 //! symbol to the `accepted` or `removed` modules respectively.
 
-#![feature(derive_default_enum)]
+#![cfg_attr(bootstrap, feature(derive_default_enum))]
 #![feature(once_cell)]
 
 mod accepted;

compiler/rustc_infer/src/infer/at.rs

@@ -63,9 +63,9 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     /// common state. Used in coherence.
     pub fn fork(&self) -> Self {
         Self {
-            tcx: self.tcx.clone(),
-            defining_use_anchor: self.defining_use_anchor.clone(),
-            in_progress_typeck_results: self.in_progress_typeck_results.clone(),
+            tcx: self.tcx,
+            defining_use_anchor: self.defining_use_anchor,
+            in_progress_typeck_results: self.in_progress_typeck_results,
             inner: self.inner.clone(),
             skip_leak_check: self.skip_leak_check.clone(),
             lexical_region_resolutions: self.lexical_region_resolutions.clone(),

compiler/rustc_infer/src/infer/mod.rs

@@ -1659,49 +1659,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         self.tcx.const_eval_resolve(param_env_erased, unevaluated, span)
     }
 
-    /// If `typ` is a type variable of some kind, resolve it one level
-    /// (but do not resolve types found in the result). If `typ` is
-    /// not a type variable, just return it unmodified.
-    // FIXME(eddyb) inline into `ShallowResolver::visit_ty`.
-    fn shallow_resolve_ty(&self, typ: Ty<'tcx>) -> Ty<'tcx> {
-        match *typ.kind() {
-            ty::Infer(ty::TyVar(v)) => {
-                // Not entirely obvious: if `typ` is a type variable,
-                // it can be resolved to an int/float variable, which
-                // can then be recursively resolved, hence the
-                // recursion. Note though that we prevent type
-                // variables from unifying to other type variables
-                // directly (though they may be embedded
-                // structurally), and we prevent cycles in any case,
-                // so this recursion should always be of very limited
-                // depth.
-                //
-                // Note: if these two lines are combined into one we get
-                // dynamic borrow errors on `self.inner`.
-                let known = self.inner.borrow_mut().type_variables().probe(v).known();
-                known.map_or(typ, |t| self.shallow_resolve_ty(t))
-            }
-
-            ty::Infer(ty::IntVar(v)) => self
-                .inner
-                .borrow_mut()
-                .int_unification_table()
-                .probe_value(v)
-                .map(|v| v.to_type(self.tcx))
-                .unwrap_or(typ),
-
-            ty::Infer(ty::FloatVar(v)) => self
-                .inner
-                .borrow_mut()
-                .float_unification_table()
-                .probe_value(v)
-                .map(|v| v.to_type(self.tcx))
-                .unwrap_or(typ),
-
-            _ => typ,
-        }
-    }
-
     /// `ty_or_const_infer_var_changed` is equivalent to one of these two:
     ///   * `shallow_resolve(ty) != ty` (where `ty.kind = ty::Infer(_)`)
     ///   * `shallow_resolve(ct) != ct` (where `ct.kind = ty::ConstKind::Infer(_)`)
@@ -1831,8 +1788,46 @@ impl<'a, 'tcx> TypeFolder<'tcx> for ShallowResolver<'a, 'tcx> {
         self.infcx.tcx
     }
 
+    /// If `ty` is a type variable of some kind, resolve it one level
+    /// (but do not resolve types found in the result). If `typ` is
+    /// not a type variable, just return it unmodified.
     fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-        self.infcx.shallow_resolve_ty(ty)
+        match *ty.kind() {
+            ty::Infer(ty::TyVar(v)) => {
+                // Not entirely obvious: if `typ` is a type variable,
+                // it can be resolved to an int/float variable, which
+                // can then be recursively resolved, hence the
+                // recursion. Note though that we prevent type
+                // variables from unifying to other type variables
+                // directly (though they may be embedded
+                // structurally), and we prevent cycles in any case,
+                // so this recursion should always be of very limited
+                // depth.
+                //
+                // Note: if these two lines are combined into one we get
+                // dynamic borrow errors on `self.inner`.
+                let known = self.infcx.inner.borrow_mut().type_variables().probe(v).known();
+                known.map_or(ty, |t| self.fold_ty(t))
+            }
+
+            ty::Infer(ty::IntVar(v)) => self
+                .infcx
+                .inner
+                .borrow_mut()
+                .int_unification_table()
+                .probe_value(v)
+                .map_or(ty, |v| v.to_type(self.infcx.tcx)),
+
+            ty::Infer(ty::FloatVar(v)) => self
+                .infcx
+                .inner
+                .borrow_mut()
+                .float_unification_table()
+                .probe_value(v)
+                .map_or(ty, |v| v.to_type(self.infcx.tcx)),
+
+            _ => ty,
+        }
     }
 
     fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> {

compiler/rustc_infer/src/lib.rs

@@ -17,7 +17,7 @@
 #![feature(bool_to_option)]
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
-#![feature(derive_default_enum)]
+#![cfg_attr(bootstrap, feature(derive_default_enum))]
 #![feature(extend_one)]
 #![feature(label_break_value)]
 #![feature(let_chains)]

compiler/rustc_macros/src/lib.rs

@@ -44,7 +44,7 @@ pub fn symbols(input: TokenStream) -> TokenStream {
 #[proc_macro]
 #[allow_internal_unstable(step_trait, rustc_attrs, trusted_step)]
 pub fn newtype_index(input: TokenStream) -> TokenStream {
-    newtype::newtype(input).into()
+    newtype::newtype(input)
 }
 
 decl_derive!([HashStable, attributes(stable_hasher)] => hash_stable::hash_stable_derive);

compiler/rustc_middle/src/lib.rs

@@ -30,7 +30,7 @@
 #![feature(bool_to_option)]
 #![feature(box_patterns)]
 #![feature(core_intrinsics)]
-#![feature(derive_default_enum)]
+#![cfg_attr(bootstrap, feature(derive_default_enum))]
 #![feature(discriminant_kind)]
 #![feature(exhaustive_patterns)]
 #![feature(get_mut_unchecked)]

compiler/rustc_middle/src/ty/inhabitedness/mod.rs

@@ -191,7 +191,7 @@ impl<'tcx> Ty<'tcx> {
         tcx: TyCtxt<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
     ) -> DefIdForest<'tcx> {
-        tcx.type_uninhabited_from(param_env.and(self)).clone()
+        tcx.type_uninhabited_from(param_env.and(self))
     }
 }
 

compiler/rustc_mir_build/src/build/expr/as_constant.rs

@@ -39,7 +39,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                         }
                     };
 
-                Constant { span, user_ty: None, literal: literal.into() }
+                Constant { span, user_ty: None, literal }
             }
             ExprKind::NonHirLiteral { lit, user_ty } => {
                 let user_ty = user_ty.map(|user_ty| {

compiler/rustc_mir_build/src/build/expr/into.rs

@@ -423,11 +423,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                         }
                         thir::InlineAsmOperand::Const { value, span } => {
                             mir::InlineAsmOperand::Const {
-                                value: Box::new(Constant {
-                                    span,
-                                    user_ty: None,
-                                    literal: value.into(),
-                                }),
+                                value: Box::new(Constant { span, user_ty: None, literal: value }),
                             }
                         }
                         thir::InlineAsmOperand::SymFn { expr } => mir::InlineAsmOperand::SymFn {

compiler/rustc_mir_build/src/build/matches/test.rs

@@ -441,7 +441,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     // Need to experiment.
                     user_ty: None,
 
-                    literal: method.into(),
+                    literal: method,
                 })),
                 args: vec![val, expect],
                 destination: Some((eq_result, eq_block)),

compiler/rustc_mir_transform/src/check_unsafety.rs

@@ -539,13 +539,13 @@ fn report_unused_unsafe(tcx: TyCtxt<'_>, kind: UnusedUnsafe, id: HirId) {
             UnusedUnsafe::InUnsafeBlock(id) => {
                 db.span_label(
                     tcx.sess.source_map().guess_head_span(tcx.hir().span(id)),
-                    format!("because it's nested under this `unsafe` block"),
+                    "because it's nested under this `unsafe` block",
                 );
             }
             UnusedUnsafe::InUnsafeFn(id, usage_lint_root) => {
                 db.span_label(
                     tcx.sess.source_map().guess_head_span(tcx.hir().span(id)),
-                    format!("because it's nested under this `unsafe` fn"),
+                    "because it's nested under this `unsafe` fn",
                 )
                 .note(
                     "this `unsafe` block does contain unsafe operations, \

compiler/rustc_parse/src/lexer/mod.rs

@@ -182,16 +182,7 @@ impl<'a> StringReader<'a> {
             }
             rustc_lexer::TokenKind::BlockComment { doc_style, terminated } => {
                 if !terminated {
-                    let msg = match doc_style {
-                        Some(_) => "unterminated block doc-comment",
-                        None => "unterminated block comment",
-                    };
-                    let last_bpos = self.pos;
-                    self.sess.span_diagnostic.span_fatal_with_code(
-                        self.mk_sp(start, last_bpos),
-                        msg,
-                        error_code!(E0758),
-                    );
+                    self.report_unterminated_block_comment(start, doc_style);
                 }
 
                 // Skip non-doc comments
@@ -234,13 +225,13 @@ impl<'a> StringReader<'a> {
             rustc_lexer::TokenKind::InvalidIdent
                 // Do not recover an identifier with emoji if the codepoint is a confusable
                 // with a recoverable substitution token, like `➖`.
-                if UNICODE_ARRAY
+                if !UNICODE_ARRAY
                     .iter()
-                    .find(|&&(c, _, _)| {
+                    .any(|&(c, _, _)| {
                         let sym = self.str_from(start);
                         sym.chars().count() == 1 && c == sym.chars().next().unwrap()
                     })
-                    .is_none() =>
+                     =>
             {
                 let sym = nfc_normalize(self.str_from(start));
                 let span = self.mk_sp(start, self.pos);
@@ -553,6 +544,55 @@ impl<'a> StringReader<'a> {
         err.emit()
     }
 
+    fn report_unterminated_block_comment(&self, start: BytePos, doc_style: Option<DocStyle>) {
+        let msg = match doc_style {
+            Some(_) => "unterminated block doc-comment",
+            None => "unterminated block comment",
+        };
+        let last_bpos = self.pos;
+        let mut err = self.sess.span_diagnostic.struct_span_fatal_with_code(
+            self.mk_sp(start, last_bpos),
+            msg,
+            error_code!(E0758),
+        );
+        let mut nested_block_comment_open_idxs = vec![];
+        let mut last_nested_block_comment_idxs = None;
+        let mut content_chars = self.str_from(start).char_indices().peekable();
+
+        while let Some((idx, current_char)) = content_chars.next() {
+            match content_chars.peek() {
+                Some((_, '*')) if current_char == '/' => {
+                    nested_block_comment_open_idxs.push(idx);
+                }
+                Some((_, '/')) if current_char == '*' => {
+                    last_nested_block_comment_idxs =
+                        nested_block_comment_open_idxs.pop().map(|open_idx| (open_idx, idx));
+                }
+                _ => {}
+            };
+        }
+
+        if let Some((nested_open_idx, nested_close_idx)) = last_nested_block_comment_idxs {
+            err.span_label(self.mk_sp(start, start + BytePos(2)), msg)
+                .span_label(
+                    self.mk_sp(
+                        start + BytePos(nested_open_idx as u32),
+                        start + BytePos(nested_open_idx as u32 + 2),
+                    ),
+                    "...as last nested comment starts here, maybe you want to close this instead?",
+                )
+                .span_label(
+                    self.mk_sp(
+                        start + BytePos(nested_close_idx as u32),
+                        start + BytePos(nested_close_idx as u32 + 2),
+                    ),
+                    "...and last nested comment terminates here.",
+                );
+        }
+
+        err.emit();
+    }
+
     // RFC 3101 introduced the idea of (reserved) prefixes. As of Rust 2021,
     // using a (unknown) prefix is an error. In earlier editions, however, they
     // only result in a (allowed by default) lint, and are treated as regular

compiler/rustc_passes/src/stability.rs

@@ -133,9 +133,9 @@ impl<'a, 'tcx> Annotator<'a, 'tcx> {
             }
 
             // `Deprecation` is just two pointers, no need to intern it
-            let depr_entry = DeprecationEntry::local(depr.clone(), def_id);
+            let depr_entry = DeprecationEntry::local(*depr, def_id);
             self.index.depr_map.insert(def_id, depr_entry);
-        } else if let Some(parent_depr) = self.parent_depr.clone() {
+        } else if let Some(parent_depr) = self.parent_depr {
             if inherit_deprecation.yes() {
                 is_deprecated = true;
                 info!("tagging child {:?} as deprecated from parent", def_id);

compiler/rustc_session/src/lib.rs

@@ -1,7 +1,7 @@
 #![feature(crate_visibility_modifier)]
-#![feature(derive_default_enum)]
 #![feature(if_let_guard)]
 #![feature(let_chains)]
+#![cfg_attr(bootstrap, feature(derive_default_enum))]
 #![feature(let_else)]
 #![feature(min_specialization)]
 #![feature(never_type)]

compiler/rustc_session/src/session.rs

@@ -238,7 +238,7 @@ impl Session {
             }
             diag.emit();
             // If we should err, make sure we did.
-            if must_err && !self.has_errors().is_some() {
+            if must_err && self.has_errors().is_none() {
                 // We have skipped a feature gate, and not run into other errors... reject.
                 self.err(
                     "`-Zunleash-the-miri-inside-of-you` may not be used to circumvent feature \