Rollup of 9 pull requests

Cargo.lock

@@ -4501,8 +4501,6 @@ dependencies = [
  "rustc_abi",
  "rustc_data_structures",
  "rustc_hir",
- "rustc_infer",
- "rustc_macros",
  "rustc_middle",
  "rustc_span",
  "tracing",

compiler/rustc_ast_lowering/messages.ftl

@@ -133,11 +133,11 @@ ast_lowering_misplaced_relax_trait_bound =
 ast_lowering_never_pattern_with_body =
     a never pattern is always unreachable
     .label = this will never be executed
-    .suggestion = remove this expression
+    .suggestion = remove the match arm expression
 
 ast_lowering_never_pattern_with_guard =
     a guard on a never pattern will never be run
-    .suggestion = remove this guard
+    .suggestion = remove the match arm guard
 
 ast_lowering_no_precise_captures_on_apit = `use<...>` precise capturing syntax not allowed in argument-position `impl Trait`
 

compiler/rustc_ast_lowering/src/errors.rs

@@ -335,7 +335,7 @@ pub(crate) struct MisplacedRelaxTraitBound {
 pub(crate) struct MatchArmWithNoBody {
     #[primary_span]
     pub span: Span,
-    #[suggestion(code = " => todo!(),", applicability = "has-placeholders")]
+    #[suggestion(code = " => todo!(),", applicability = "has-placeholders", style = "verbose")]
     pub suggestion: Span,
 }
 
@@ -344,16 +344,18 @@ pub(crate) struct MatchArmWithNoBody {
 pub(crate) struct NeverPatternWithBody {
     #[primary_span]
     #[label]
-    #[suggestion(code = "", applicability = "maybe-incorrect")]
     pub span: Span,
+    #[suggestion(code = ",", applicability = "maybe-incorrect", style = "verbose")]
+    pub removal_span: Span,
 }
 
 #[derive(Diagnostic)]
 #[diag(ast_lowering_never_pattern_with_guard)]
 pub(crate) struct NeverPatternWithGuard {
     #[primary_span]
-    #[suggestion(code = "", applicability = "maybe-incorrect")]
     pub span: Span,
+    #[suggestion(code = ",", applicability = "maybe-incorrect", style = "verbose")]
+    pub removal_span: Span,
 }
 
 #[derive(Diagnostic)]

compiler/rustc_ast_lowering/src/expr.rs

@@ -676,6 +676,16 @@ impl<'hir> LoweringContext<'_, 'hir> {
         {
             self.lower_expr(body)
         } else {
+            let removal_span = |removal_span: Span| {
+                // Seek upwards in the macro call sites to see if we find the place where
+                // `pat!()` was called so that we can get the right span to remove.
+                let Some(pat_span) = pat.span.find_ancestor_in_same_ctxt(arm.span) else {
+                    return removal_span;
+                };
+                // - pat!() => {}
+                // + pat!(),
+                pat_span.shrink_to_hi().with_hi(arm.span.hi())
+            };
             // Either `body.is_none()` or `is_never_pattern` here.
             if !is_never_pattern {
                 if self.tcx.features().never_patterns() {
@@ -684,9 +694,15 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     self.dcx().emit_err(MatchArmWithNoBody { span, suggestion });
                 }
             } else if let Some(body) = &arm.body {
-                self.dcx().emit_err(NeverPatternWithBody { span: body.span });
+                self.dcx().emit_err(NeverPatternWithBody {
+                    span: body.span,
+                    removal_span: removal_span(body.span),
+                });
             } else if let Some(g) = &arm.guard {
-                self.dcx().emit_err(NeverPatternWithGuard { span: g.span });
+                self.dcx().emit_err(NeverPatternWithGuard {
+                    span: g.span,
+                    removal_span: removal_span(g.span),
+                });
             }
 
             // We add a fake `loop {}` arm body so that it typecks to `!`. The mir lowering of never

compiler/rustc_ast_lowering/src/pat.rs

@@ -20,7 +20,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         self.arena.alloc(self.lower_pat_mut(pattern))
     }
 
-    fn lower_pat_mut(&mut self, mut pattern: &Pat) -> hir::Pat<'hir> {
+    fn lower_pat_mut(&mut self, outer_pattern: &Pat) -> hir::Pat<'hir> {
+        let mut pattern = outer_pattern;
         ensure_sufficient_stack(|| {
             // loop here to avoid recursion
             let pat_hir_id = self.lower_node_id(pattern.id);
@@ -147,7 +148,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 }
             };
 
-            self.pat_with_node_id_of(pattern, node, pat_hir_id)
+            self.pat_with_node_id_of(outer_pattern, node, pat_hir_id)
         })
     }
 

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -38,7 +38,7 @@ use rustc_mir_dataflow::move_paths::MoveData;
 use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_span::def_id::CRATE_DEF_ID;
 use rustc_span::source_map::Spanned;
-use rustc_span::{DUMMY_SP, Span, sym};
+use rustc_span::{Span, sym};
 use rustc_trait_selection::traits::query::type_op::custom::scrape_region_constraints;
 use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput};
 use tracing::{debug, instrument, trace};
@@ -51,7 +51,6 @@ use crate::polonius::legacy::{PoloniusFacts, PoloniusLocationTable};
 use crate::polonius::{PoloniusContext, PoloniusLivenessContext};
 use crate::region_infer::TypeTest;
 use crate::region_infer::values::{LivenessValues, PlaceholderIndex, PlaceholderIndices};
-use crate::renumber::RegionCtxt;
 use crate::session_diagnostics::{MoveUnsized, SimdIntrinsicArgConst};
 use crate::type_check::free_region_relations::{CreateResult, UniversalRegionRelations};
 use crate::universal_regions::{DefiningTy, UniversalRegions};
@@ -2121,35 +2120,31 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                                 //
                                 // Note that other checks (such as denying `dyn Send` -> `dyn
                                 // Debug`) are in `rustc_hir_typeck`.
-                                if let ty::Dynamic(src_tty, ..) = src_tail.kind()
-                                    && let ty::Dynamic(dst_tty, ..) = dst_tail.kind()
+                                if let ty::Dynamic(src_tty, _src_lt, _) = *src_tail.kind()
+                                    && let ty::Dynamic(dst_tty, dst_lt, _) = *dst_tail.kind()
                                     && src_tty.principal().is_some()
                                     && dst_tty.principal().is_some()
                                 {
                                     // Remove auto traits.
                                     // Auto trait checks are handled in `rustc_hir_typeck` as FCW.
-                                    let src_obj = tcx.mk_ty_from_kind(ty::Dynamic(
+                                    let src_obj = Ty::new_dynamic(
+                                        tcx,
                                         tcx.mk_poly_existential_predicates(
                                             &src_tty.without_auto_traits().collect::<Vec<_>>(),
                                         ),
-                                        tcx.lifetimes.re_static,
+                                        // FIXME: Once we disallow casting `*const dyn Trait + 'short`
+                                        // to `*const dyn Trait + 'long`, then this can just be `src_lt`.
+                                        dst_lt,
                                         ty::Dyn,
-                                    ));
-                                    let dst_obj = tcx.mk_ty_from_kind(ty::Dynamic(
+                                    );
+                                    let dst_obj = Ty::new_dynamic(
+                                        tcx,
                                         tcx.mk_poly_existential_predicates(
                                             &dst_tty.without_auto_traits().collect::<Vec<_>>(),
                                         ),
-                                        tcx.lifetimes.re_static,
+                                        dst_lt,
                                         ty::Dyn,
-                                    ));
-
-                                    // Replace trait object lifetimes with fresh vars, to allow
-                                    // casts like
-                                    // `*mut dyn FnOnce() + 'a` -> `*mut dyn FnOnce() + 'static`
-                                    let src_obj =
-                                        freshen_single_trait_object_lifetime(self.infcx, src_obj);
-                                    let dst_obj =
-                                        freshen_single_trait_object_lifetime(self.infcx, dst_obj);
+                                    );
 
                                     debug!(?src_tty, ?dst_tty, ?src_obj, ?dst_obj);
 
@@ -2707,16 +2702,3 @@ impl<'tcx> TypeOp<'tcx> for InstantiateOpaqueType<'tcx> {
         Ok(output)
     }
 }
-
-fn freshen_single_trait_object_lifetime<'tcx>(
-    infcx: &BorrowckInferCtxt<'tcx>,
-    ty: Ty<'tcx>,
-) -> Ty<'tcx> {
-    let &ty::Dynamic(tty, _, dyn_kind @ ty::Dyn) = ty.kind() else { bug!("expected trait object") };
-
-    let fresh = infcx
-        .next_region_var(rustc_infer::infer::RegionVariableOrigin::MiscVariable(DUMMY_SP), || {
-            RegionCtxt::Unknown
-        });
-    infcx.tcx.mk_ty_from_kind(ty::Dynamic(tty, fresh, dyn_kind))
-}

compiler/rustc_const_eval/messages.ftl

@@ -109,6 +109,8 @@ const_eval_frame_note_inner = inside {$where_ ->
     *[other] {""}
 }
 
+const_eval_frame_note_last = the failure occurred here
+
 const_eval_in_bounds_test = out-of-bounds pointer use
 const_eval_incompatible_calling_conventions =
     calling a function with calling convention {$callee_conv} using calling convention {$caller_conv}
@@ -300,8 +302,7 @@ const_eval_overflow_arith =
 const_eval_overflow_shift =
     overflowing shift by {$shift_amount} in `{$intrinsic}`
 
-const_eval_panic =
-    the evaluated program panicked at '{$msg}', {$file}:{$line}:{$col}
+const_eval_panic = evaluation panicked: {$msg}
 
 const_eval_panic_non_str = argument to `panic!()` in a const context must have type `&str`
 

compiler/rustc_const_eval/src/const_eval/error.rs

@@ -48,11 +48,8 @@ impl MachineStopType for ConstEvalErrKind {
             | ModifiedGlobal
             | WriteThroughImmutablePointer => {}
             AssertFailure(kind) => kind.add_args(adder),
-            Panic { msg, line, col, file } => {
+            Panic { msg, .. } => {
                 adder("msg".into(), msg.into_diag_arg(&mut None));
-                adder("file".into(), file.into_diag_arg(&mut None));
-                adder("line".into(), line.into_diag_arg(&mut None));
-                adder("col".into(), col.into_diag_arg(&mut None));
             }
         }
     }
@@ -72,7 +69,7 @@ pub fn get_span_and_frames<'tcx>(
     let mut stacktrace = Frame::generate_stacktrace_from_stack(stack);
     // Filter out `requires_caller_location` frames.
     stacktrace.retain(|frame| !frame.instance.def.requires_caller_location(*tcx));
-    let span = stacktrace.first().map(|f| f.span).unwrap_or(tcx.span);
+    let span = stacktrace.last().map(|f| f.span).unwrap_or(tcx.span);
 
     let mut frames = Vec::new();
 
@@ -115,6 +112,20 @@ pub fn get_span_and_frames<'tcx>(
         }
     }
 
+    // In `rustc`, we present const-eval errors from the outer-most place first to the inner-most.
+    // So we reverse the frames here. The first frame will be the same as the span from the current
+    // `TyCtxtAt<'_>`, so we remove it as it would be redundant.
+    frames.reverse();
+    if frames.len() > 0 {
+        frames.remove(0);
+    }
+    if let Some(last) = frames.last_mut()
+        // If the span is not going to be printed, we don't want the span label for `is_last`.
+        && tcx.sess.source_map().span_to_snippet(last.span.source_callsite()).is_ok()
+    {
+        last.has_label = true;
+    }
+
     (span, frames)
 }
 

compiler/rustc_const_eval/src/errors.rs

@@ -6,6 +6,7 @@ use rustc_abi::WrappingRange;
 use rustc_errors::codes::*;
 use rustc_errors::{
     Diag, DiagArgValue, DiagCtxtHandle, DiagMessage, Diagnostic, EmissionGuarantee, Level,
+    MultiSpan, SubdiagMessageOp, Subdiagnostic,
 };
 use rustc_hir::ConstContext;
 use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic};
@@ -17,6 +18,7 @@ use rustc_middle::mir::interpret::{
 use rustc_middle::ty::{self, Mutability, Ty};
 use rustc_span::{Span, Symbol};
 
+use crate::fluent_generated as fluent;
 use crate::interpret::InternKind;
 
 #[derive(Diagnostic)]
@@ -278,14 +280,31 @@ pub(crate) struct NonConstImplNote {
     pub span: Span,
 }
 
-#[derive(Subdiagnostic, Clone)]
-#[note(const_eval_frame_note)]
+#[derive(Clone)]
 pub struct FrameNote {
-    #[primary_span]
     pub span: Span,
     pub times: i32,
     pub where_: &'static str,
     pub instance: String,
+    pub has_label: bool,
+}
+
+impl Subdiagnostic for FrameNote {
+    fn add_to_diag_with<G: EmissionGuarantee, F: SubdiagMessageOp<G>>(
+        self,
+        diag: &mut Diag<'_, G>,
+        f: &F,
+    ) {
+        diag.arg("times", self.times);
+        diag.arg("where_", self.where_);
+        diag.arg("instance", self.instance);
+        let mut span: MultiSpan = self.span.into();
+        if self.has_label && !self.span.is_dummy() {
+            span.push_span_label(self.span, fluent::const_eval_frame_note_last);
+        }
+        let msg = f(diag, fluent::const_eval_frame_note.into());
+        diag.span_note(span, msg);
+    }
 }
 
 #[derive(Subdiagnostic)]

compiler/rustc_const_eval/src/interpret/stack.rs

@@ -231,13 +231,19 @@ impl<'tcx> FrameInfo<'tcx> {
     pub fn as_note(&self, tcx: TyCtxt<'tcx>) -> errors::FrameNote {
         let span = self.span;
         if tcx.def_key(self.instance.def_id()).disambiguated_data.data == DefPathData::Closure {
-            errors::FrameNote { where_: "closure", span, instance: String::new(), times: 0 }
+            errors::FrameNote {
+                where_: "closure",
+                span,
+                instance: String::new(),
+                times: 0,
+                has_label: false,
+            }
         } else {
             let instance = format!("{}", self.instance);
             // Note: this triggers a `must_produce_diag` state, which means that if we ever get
             // here we must emit a diagnostic. We should never display a `FrameInfo` unless we
             // actually want to emit a warning or error to the user.
-            errors::FrameNote { where_: "instance", span, instance, times: 0 }
+            errors::FrameNote { where_: "instance", span, instance, times: 0, has_label: false }
         }
     }
 }

compiler/rustc_feature/src/unstable.rs

@@ -508,6 +508,8 @@ declare_features! (
     (incomplete, generic_const_exprs, "1.56.0", Some(76560)),
     /// Allows generic parameters and where-clauses on free & associated const items.
     (incomplete, generic_const_items, "1.73.0", Some(113521)),
+    /// Allows the type of const generics to depend on generic parameters
+    (incomplete, generic_const_parameter_types, "CURRENT_RUSTC_VERSION", Some(137626)),
     /// Allows any generic constants being used as pattern type range ends
     (incomplete, generic_pattern_types, "1.86.0", Some(136574)),
     /// Allows registering static items globally, possibly across crates, to iterate over at runtime.

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -966,7 +966,7 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) -> Result<(),
             let ty = tcx.type_of(param.def_id).instantiate_identity();
 
             if tcx.features().unsized_const_params() {
-                enter_wf_checking_ctxt(tcx, hir_ty.span, param.def_id, |wfcx| {
+                enter_wf_checking_ctxt(tcx, hir_ty.span, tcx.local_parent(param.def_id), |wfcx| {
                     wfcx.register_bound(
                         ObligationCause::new(
                             hir_ty.span,
@@ -980,7 +980,7 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) -> Result<(),
                     Ok(())
                 })
             } else if tcx.features().adt_const_params() {
-                enter_wf_checking_ctxt(tcx, hir_ty.span, param.def_id, |wfcx| {
+                enter_wf_checking_ctxt(tcx, hir_ty.span, tcx.local_parent(param.def_id), |wfcx| {
                     wfcx.register_bound(
                         ObligationCause::new(
                             hir_ty.span,

compiler/rustc_hir_analysis/src/collect.rs

@@ -1822,6 +1822,9 @@ fn const_param_default<'tcx>(
         ),
     };
     let icx = ItemCtxt::new(tcx, def_id);
-    let ct = icx.lowerer().lower_const_arg(default_ct, FeedConstTy::Param(def_id.to_def_id()));
+    let identity_args = ty::GenericArgs::identity_for_item(tcx, def_id);
+    let ct = icx
+        .lowerer()
+        .lower_const_arg(default_ct, FeedConstTy::Param(def_id.to_def_id(), identity_args));
     ty::EarlyBinder::bind(ct)
 }

compiler/rustc_hir_analysis/src/collect/predicates_of.rs

@@ -223,10 +223,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen
             }
             hir::GenericParamKind::Const { .. } => {
                 let param_def_id = param.def_id.to_def_id();
-                let ct_ty = tcx
-                    .type_of(param_def_id)
-                    .no_bound_vars()
-                    .expect("const parameters cannot be generic");
+                let ct_ty = tcx.type_of(param_def_id).instantiate_identity();
                 let ct = icx.lowerer().lower_const_param(param_def_id, param.hir_id);
                 predicates
                     .insert((ty::ClauseKind::ConstArgHasType(ct, ct_ty).upcast(tcx), param.span));

compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs

@@ -273,7 +273,7 @@ pub fn lower_generic_args<'tcx: 'a, 'a>(
 
                             // We lower to an infer even when the feature gate is not enabled
                             // as it is useful for diagnostics to be able to see a `ConstKind::Infer`
-                            args.push(ctx.provided_kind(param, arg));
+                            args.push(ctx.provided_kind(&args, param, arg));
                             args_iter.next();
                             params.next();
                         }