Auto merge of rust-lang#137848 - matthiaskrgr:rollup-vxtrkis, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - rust-lang#136503 (Tweak output of const panic diagnostic)
 - rust-lang#137390 (tests: fix up new test for nocapture -> capture(none) change)
 - rust-lang#137617 (Introduce `feature(generic_const_parameter_types)`)
 - rust-lang#137719 (Add missing case explanation for doc inlined re-export of doc hidden item)
 - rust-lang#137763 (Use `mk_ty_from_kind` a bit less, clean up lifetime handling in borrowck)
 - rust-lang#137769 (Do not yeet `unsafe<>` from type when formatting unsafe binder)
 - rust-lang#137776 (Some `rustc_transmute` cleanups)
 - rust-lang#137800 (Remove `ParamEnv::without_caller_bounds`)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

Diff for: Cargo.lock

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

Diff for: 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))
-}

Diff for: 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`
 

Diff for: 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)
 }
 

Diff for: 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)]

Diff for: 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 }
         }
     }
 }

Diff for: 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.

Diff for: 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,

Diff for: 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)
 }

Diff for: 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));

Diff for: 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();
                         }