Merge from rustc

Author: The Miri Conjob Bot

compiler/rustc_error_codes/src/error_codes/E0647.md

@@ -7,7 +7,7 @@ Erroneous code example:
 
 #[start]
 fn start(_: isize, _: *const *const u8) -> isize where (): Copy {
-    //^ error: start function is not allowed to have a where clause
+    //^ error: `#[start]` function is not allowed to have a where clause
     0
 }
 ```

compiler/rustc_errors/src/diagnostic.rs

@@ -151,7 +151,12 @@ impl fmt::Display for DiagnosticLocation {
 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
 pub enum DiagnosticId {
     Error(String),
-    Lint { name: String, has_future_breakage: bool, is_force_warn: bool },
+    Lint {
+        name: String,
+        /// Indicates whether this lint should show up in cargo's future breakage report.
+        has_future_breakage: bool,
+        is_force_warn: bool,
+    },
 }
 
 /// A "sub"-diagnostic attached to a parent diagnostic.
@@ -301,6 +306,7 @@ impl Diagnostic {
         }
     }
 
+    /// Indicates whether this diagnostic should show up in cargo's future breakage report.
     pub fn has_future_breakage(&self) -> bool {
         match self.code {
             Some(DiagnosticId::Lint { has_future_breakage, .. }) => has_future_breakage,

compiler/rustc_errors/src/lib.rs

@@ -519,7 +519,7 @@ pub struct HandlerFlags {
     /// If false, warning-level lints are suppressed.
     /// (rustc: see `--allow warnings` and `--cap-lints`)
     pub can_emit_warnings: bool,
-    /// If true, error-level diagnostics are upgraded to bug-level.
+    /// If Some, the Nth error-level diagnostic is upgraded to bug-level.
     /// (rustc: see `-Z treat-err-as-bug`)
     pub treat_err_as_bug: Option<NonZeroUsize>,
     /// If true, immediately emit diagnostics that would otherwise be buffered.
@@ -1719,19 +1719,17 @@ impl HandlerInner {
             match (
                 self.err_count() + self.lint_err_count,
                 self.delayed_bug_count(),
-                self.flags.treat_err_as_bug.map(|c| c.get()).unwrap_or(0),
+                self.flags.treat_err_as_bug.map(|c| c.get()).unwrap(),
             ) {
                 (1, 0, 1) => panic!("aborting due to `-Z treat-err-as-bug=1`"),
                 (0, 1, 1) => panic!("aborting due delayed bug with `-Z treat-err-as-bug=1`"),
-                (count, delayed_count, as_bug) => {
+                (count, delayed_count, val) => {
                     if delayed_count > 0 {
                         panic!(
-                            "aborting after {count} errors and {delayed_count} delayed bugs due to `-Z treat-err-as-bug={as_bug}`",
+                            "aborting after {count} errors and {delayed_count} delayed bugs due to `-Z treat-err-as-bug={val}`",
                         )
                     } else {
-                        panic!(
-                            "aborting after {count} errors due to `-Z treat-err-as-bug={as_bug}`",
-                        )
+                        panic!("aborting after {count} errors due to `-Z treat-err-as-bug={val}`")
                     }
                 }
             }

compiler/rustc_hir_analysis/messages.ftl

@@ -270,20 +270,20 @@ hir_analysis_simd_ffi_highly_experimental = use of SIMD type{$snip} in FFI is hi
 hir_analysis_specialization_trait = implementing `rustc_specialization_trait` traits is unstable
     .help = add `#![feature(min_specialization)]` to the crate attributes to enable
 
-hir_analysis_start_function_parameters = start function is not allowed to have type parameters
-    .label = start function cannot have type parameters
+hir_analysis_start_function_parameters = `#[start]` function is not allowed to have type parameters
+    .label = `#[start]` function cannot have type parameters
 
-hir_analysis_start_function_where = start function is not allowed to have a `where` clause
-    .label = start function cannot have a `where` clause
+hir_analysis_start_function_where = `#[start]` function is not allowed to have a `where` clause
+    .label = `#[start]` function cannot have a `where` clause
 
-hir_analysis_start_not_async = `start` is not allowed to be `async`
-    .label = `start` is not allowed to be `async`
+hir_analysis_start_not_async = `#[start]` function is not allowed to be `async`
+    .label = `#[start]` is not allowed to be `async`
 
-hir_analysis_start_not_target_feature = `start` is not allowed to have `#[target_feature]`
-    .label = `start` is not allowed to have `#[target_feature]`
+hir_analysis_start_not_target_feature = `#[start]` function is not allowed to have `#[target_feature]`
+    .label = `#[start]` function is not allowed to have `#[target_feature]`
 
-hir_analysis_start_not_track_caller = `start` is not allowed to be `#[track_caller]`
-    .label = `start` is not allowed to be `#[track_caller]`
+hir_analysis_start_not_track_caller = `#[start]` function is not allowed to be `#[track_caller]`
+    .label = `#[start]` function is not allowed to be `#[track_caller]`
 
 hir_analysis_static_specialize = cannot specialize on `'static` lifetime
 

compiler/rustc_hir_analysis/src/check/check.rs

@@ -18,7 +18,7 @@ use rustc_infer::traits::{Obligation, TraitEngineExt as _};
 use rustc_lint_defs::builtin::REPR_TRANSPARENT_EXTERNAL_PRIVATE_FIELDS;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::stability::EvalResult;
-use rustc_middle::traits::DefiningAnchor;
+use rustc_middle::traits::{DefiningAnchor, ObligationCauseCode};
 use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::layout::{LayoutError, MAX_SIMD_LANES};
 use rustc_middle::ty::util::{Discr, IntTypeExt};
@@ -1626,6 +1626,25 @@ pub(super) fn check_generator_obligations(tcx: TyCtxt<'_>, def_id: LocalDefId) {
         let obligation = Obligation::new(tcx, cause.clone(), param_env, *predicate);
         fulfillment_cx.register_predicate_obligation(&infcx, obligation);
     }
+
+    if (tcx.features().unsized_locals || tcx.features().unsized_fn_params)
+        && let Some(generator) = tcx.mir_generator_witnesses(def_id)
+    {
+        for field_ty in generator.field_tys.iter() {
+            fulfillment_cx.register_bound(
+                &infcx,
+                param_env,
+                field_ty.ty,
+                tcx.require_lang_item(hir::LangItem::Sized, Some(field_ty.source_info.span)),
+                ObligationCause::new(
+                    field_ty.source_info.span,
+                    def_id,
+                    ObligationCauseCode::SizedGeneratorInterior(def_id),
+                ),
+            );
+        }
+    }
+
     let errors = fulfillment_cx.select_all_or_error(&infcx);
     debug!(?errors);
     if !errors.is_empty() {

compiler/rustc_hir_analysis/src/collect/type_of/opaque.rs

@@ -1,7 +1,7 @@
 use rustc_errors::StashKey;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::intravisit::{self, Visitor};
-use rustc_hir::{self as hir, Expr, ImplItem, Item, Node, TraitItem};
+use rustc_hir::{self as hir, def, Expr, ImplItem, Item, Node, TraitItem};
 use rustc_middle::hir::nested_filter;
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt};
 use rustc_span::DUMMY_SP;
@@ -74,9 +74,14 @@ pub(super) fn find_opaque_ty_constraints_for_tait(tcx: TyCtxt<'_>, def_id: Local
 
         hidden.ty
     } else {
+        let mut parent_def_id = def_id;
+        while tcx.def_kind(parent_def_id) == def::DefKind::OpaqueTy {
+            // Account for `type Alias = impl Trait<Foo = impl Trait>;` (#116031)
+            parent_def_id = tcx.local_parent(parent_def_id);
+        }
         let reported = tcx.sess.emit_err(UnconstrainedOpaqueType {
             span: tcx.def_span(def_id),
-            name: tcx.item_name(tcx.local_parent(def_id).to_def_id()),
+            name: tcx.item_name(parent_def_id.to_def_id()),
             what: match tcx.hir().get(scope) {
                 _ if scope == hir::CRATE_HIR_ID => "module",
                 Node::Item(hir::Item { kind: hir::ItemKind::Mod(_), .. }) => "module",

compiler/rustc_hir_typeck/src/cast.rs

@@ -725,6 +725,9 @@ impl<'a, 'tcx> CastCheck<'tcx> {
                             },
                             // array-ptr-cast
                             Ptr(mt) => {
+                                if !fcx.type_is_sized_modulo_regions(fcx.param_env, mt.ty) {
+                                    return Err(CastError::IllegalCast);
+                                }
                                 self.check_ref_cast(fcx, TypeAndMut { mutbl, ty: inner_ty }, mt)
                             }
                             _ => Err(CastError::NonScalar),
@@ -735,15 +738,13 @@ impl<'a, 'tcx> CastCheck<'tcx> {
             }
             _ => return Err(CastError::NonScalar),
         };
-
         if let ty::Adt(adt_def, _) = *self.expr_ty.kind() {
             if adt_def.did().krate != LOCAL_CRATE {
                 if adt_def.variants().iter().any(VariantDef::is_field_list_non_exhaustive) {
                     return Err(CastError::ForeignNonExhaustiveAdt);
                 }
             }
         }
-
         match (t_from, t_cast) {
             // These types have invariants! can't cast into them.
             (_, Int(CEnum) | FnPtr) => Err(CastError::NonScalar),

compiler/rustc_hir_typeck/src/expr.rs

@@ -525,8 +525,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             _ => self.instantiate_value_path(segs, opt_ty, res, expr.span, expr.hir_id).0,
         };
 
-        if let ty::FnDef(did, ..) = *ty.kind() {
+        if let ty::FnDef(did, callee_args) = *ty.kind() {
             let fn_sig = ty.fn_sig(tcx);
+
+            // HACK: whenever we get a FnDef in a non-const context, enforce effects to get the
+            // default `host = true` to avoid inference errors later.
+            if tcx.hir().body_const_context(self.body_id).is_none() {
+                self.enforce_context_effects(expr.hir_id, qpath.span(), did, callee_args);
+            }
             if tcx.fn_sig(did).skip_binder().abi() == RustIntrinsic
                 && tcx.item_name(did) == sym::transmute
             {

compiler/rustc_hir_typeck/src/expr_use_visitor.rs

@@ -664,10 +664,12 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
         );
         self.walk_pat(discr_place, arm.pat, arm.guard.is_some());
 
-        if let Some(hir::Guard::If(e)) = arm.guard {
-            self.consume_expr(e)
-        } else if let Some(hir::Guard::IfLet(ref l)) = arm.guard {
-            self.consume_expr(l.init)
+        match arm.guard {
+            Some(hir::Guard::If(ref e)) => self.consume_expr(e),
+            Some(hir::Guard::IfLet(ref l)) => {
+                self.walk_local(l.init, l.pat, None, |t| t.borrow_expr(l.init, ty::ImmBorrow))
+            }
+            None => {}
         }
 
         self.consume_expr(arm.body);

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -518,8 +518,15 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         self.select_obligations_where_possible(|_| {});
 
         let mut generators = self.deferred_generator_interiors.borrow_mut();
-        for (_, body_id, interior, kind) in generators.drain(..) {
-            crate::generator_interior::resolve_interior(self, def_id, body_id, interior, kind);
+        for (generator_def_id, body_id, interior, kind) in generators.drain(..) {
+            crate::generator_interior::resolve_interior(
+                self,
+                def_id,
+                generator_def_id,
+                body_id,
+                interior,
+                kind,
+            );
             self.select_obligations_where_possible(|_| {});
         }
     }

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -273,11 +273,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             //
             // This check is here because there is currently no way to express a trait bound for `FnDef` types only.
             if is_const_eval_select && (1..=2).contains(&idx) {
-                if let ty::FnDef(def_id, _) = checked_ty.kind() {
-                    if idx == 1 && !self.tcx.is_const_fn_raw(*def_id) {
-                        self.tcx
-                            .sess
-                            .emit_err(errors::ConstSelectMustBeConst { span: provided_arg.span });
+                if let ty::FnDef(def_id, args) = *checked_ty.kind() {
+                    if idx == 1 {
+                        if !self.tcx.is_const_fn_raw(def_id) {
+                            self.tcx.sess.emit_err(errors::ConstSelectMustBeConst {
+                                span: provided_arg.span,
+                            });
+                        } else {
+                            self.enforce_context_effects(
+                                provided_arg.hir_id,
+                                provided_arg.span,
+                                def_id,
+                                args,
+                            )
+                        }
                     }
                 } else {
                     self.tcx.sess.emit_err(errors::ConstSelectMustBeFn {

compiler/rustc_hir_typeck/src/generator_interior/mod.rs

@@ -9,12 +9,13 @@ use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
 use rustc_errors::{pluralize, DelayDm};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
-use rustc_hir::def_id::DefId;
+use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::hir_id::HirIdSet;
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{Arm, Expr, ExprKind, Guard, HirId, Pat, PatKind};
 use rustc_infer::infer::{DefineOpaqueTypes, RegionVariableOrigin};
 use rustc_middle::middle::region::{self, Scope, ScopeData, YieldData};
+use rustc_middle::traits::ObligationCauseCode;
 use rustc_middle::ty::fold::FnMutDelegate;
 use rustc_middle::ty::{self, BoundVariableKind, RvalueScopes, Ty, TyCtxt, TypeVisitableExt};
 use rustc_span::symbol::sym;
@@ -188,6 +189,7 @@ impl<'a, 'tcx> InteriorVisitor<'a, 'tcx> {
 pub fn resolve_interior<'a, 'tcx>(
     fcx: &'a FnCtxt<'a, 'tcx>,
     def_id: DefId,
+    generator_def_id: LocalDefId,
     body_id: hir::BodyId,
     interior: Ty<'tcx>,
     kind: hir::GeneratorKind,
@@ -214,6 +216,16 @@ pub fn resolve_interior<'a, 'tcx>(
     // The types are already kept in insertion order.
     let types = visitor.types;
 
+    if fcx.tcx.features().unsized_locals || fcx.tcx.features().unsized_fn_params {
+        for interior_ty in &types {
+            fcx.require_type_is_sized(
+                interior_ty.ty,
+                interior_ty.span,
+                ObligationCauseCode::SizedGeneratorInterior(generator_def_id),
+            );
+        }
+    }
+
     // The types in the generator interior contain lifetimes local to the generator itself,
     // which should not be exposed outside of the generator. Therefore, we replace these
     // lifetimes with existentially-bound lifetimes, which reflect the exact value of the

compiler/rustc_hir_typeck/src/upvar.rs

@@ -41,6 +41,7 @@ use rustc_hir::intravisit::{self, Visitor};
 use rustc_infer::infer::UpvarRegion;
 use rustc_middle::hir::place::{Place, PlaceBase, PlaceWithHirId, Projection, ProjectionKind};
 use rustc_middle::mir::FakeReadCause;
+use rustc_middle::traits::ObligationCauseCode;
 use rustc_middle::ty::{
     self, ClosureSizeProfileData, Ty, TyCtxt, TypeckResults, UpvarArgs, UpvarCapture,
 };
@@ -295,6 +296,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let final_upvar_tys = self.final_upvar_tys(closure_def_id);
         debug!(?closure_hir_id, ?args, ?final_upvar_tys);
 
+        if self.tcx.features().unsized_locals || self.tcx.features().unsized_fn_params {
+            for capture in
+                self.typeck_results.borrow().closure_min_captures_flattened(closure_def_id)
+            {
+                if let UpvarCapture::ByValue = capture.info.capture_kind {
+                    self.require_type_is_sized(
+                        capture.place.ty(),
+                        capture.get_path_span(self.tcx),
+                        ObligationCauseCode::SizedClosureCapture(closure_def_id),
+                    );
+                }
+            }
+        }
+
         // Build a tuple (U0..Un) of the final upvar types U0..Un
         // and unify the upvar tuple type in the closure with it:
         let final_tupled_upvars_type = Ty::new_tup(self.tcx, &final_upvar_tys);

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -1616,7 +1616,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                     //    |     expected `()`, found closure
                     //    |
                     //    = note: expected unit type `()`
-                    //                 found closure `[closure@$DIR/issue-20862.rs:2:5: 2:14 x:_]`
+                    //                 found closure `{closure@$DIR/issue-20862.rs:2:5: 2:14 x:_}`
                     //
                     // Also ignore opaque `Future`s that come from async fns.
                     if !self.ignore_span.overlaps(span)

compiler/rustc_lint/src/array_into_iter.rs

@@ -34,8 +34,8 @@ declare_lint! {
     Warn,
     "detects calling `into_iter` on arrays in Rust 2015 and 2018",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>",
         reason: FutureIncompatibilityReason::EditionSemanticsChange(Edition::Edition2021),
+        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>",
     };
 }
 

compiler/rustc_lint/src/builtin.rs

@@ -844,8 +844,8 @@ declare_lint! {
     Warn,
     "detects anonymous parameters",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
         reason: FutureIncompatibilityReason::EditionError(Edition::Edition2018),
+        reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
     };
 }
 
@@ -1669,8 +1669,8 @@ declare_lint! {
     Warn,
     "`...` range patterns are deprecated",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>",
         reason: FutureIncompatibilityReason::EditionError(Edition::Edition2021),
+        reference: "<https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>",
     };
 }
 
@@ -1804,8 +1804,8 @@ declare_lint! {
     Allow,
     "detects edition keywords being used as an identifier",
     @future_incompatible = FutureIncompatibleInfo {
-        reference: "issue #49716 <https://github.com/rust-lang/rust/issues/49716>",
         reason: FutureIncompatibilityReason::EditionError(Edition::Edition2018),
+        reference: "issue #49716 <https://github.com/rust-lang/rust/issues/49716>",
     };
 }
 

compiler/rustc_lint/src/deref_into_dyn_supertrait.rs

@@ -5,6 +5,7 @@ use crate::{
 
 use rustc_hir as hir;
 use rustc_middle::{traits::util::supertraits, ty};
+use rustc_session::lint::FutureIncompatibilityReason;
 use rustc_span::sym;
 
 declare_lint! {
@@ -48,6 +49,7 @@ declare_lint! {
     Warn,
     "`Deref` implementation usage with a supertrait trait object for output might be shadowed in the future",
     @future_incompatible = FutureIncompatibleInfo {
+        reason: FutureIncompatibilityReason::FutureReleaseErrorDontReportInDeps,
         reference: "issue #89460 <https://github.com/rust-lang/rust/issues/89460>",
     };
 }