Rollup of 6 pull requests

compiler/rustc_borrowck/src/type_check/input_output.rs

@@ -7,13 +7,16 @@
 //! `RETURN_PLACE` the MIR arguments) are always fully normalized (and
 //! contain revealed `impl Trait` values).
 
+use crate::type_check::constraint_conversion::ConstraintConversion;
 use rustc_index::vec::Idx;
 use rustc_infer::infer::LateBoundRegionConversionTime;
 use rustc_middle::mir::*;
-use rustc_middle::traits::ObligationCause;
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::ty::Ty;
 use rustc_span::Span;
-use rustc_trait_selection::traits::query::normalize::AtExt;
+use rustc_span::DUMMY_SP;
+use rustc_trait_selection::traits::query::type_op::{self, TypeOp};
+use rustc_trait_selection::traits::query::Fallible;
+use type_op::TypeOpOutput;
 
 use crate::universal_regions::UniversalRegions;
 
@@ -30,6 +33,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         let (&normalized_output_ty, normalized_input_tys) =
             normalized_inputs_and_output.split_last().unwrap();
 
+        debug!(?normalized_output_ty);
+        debug!(?normalized_input_tys);
+
         let mir_def_id = body.source.def_id().expect_local();
 
         // If the user explicitly annotated the input types, extract
@@ -75,10 +81,12 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     .delay_span_bug(body.span, "found more normalized_input_ty than local_decls");
                 break;
             }
+
             // In MIR, argument N is stored in local N+1.
             let local = Local::new(argument_index + 1);
 
             let mir_input_ty = body.local_decls[local].ty;
+
             let mir_input_span = body.local_decls[local].source_info.span;
             self.equate_normalized_input_or_output(
                 normalized_input_ty,
@@ -100,6 +108,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 // If the user explicitly annotated the input types, enforce those.
                 let user_provided_input_ty =
                     self.normalize(user_provided_input_ty, Locations::All(mir_input_span));
+
                 self.equate_normalized_input_or_output(
                     user_provided_input_ty,
                     mir_input_ty,
@@ -167,30 +176,14 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             // `rustc_traits::normalize_after_erasing_regions`. Ideally, we'd
             // like to normalize *before* inserting into `local_decls`, but
             // doing so ends up causing some other trouble.
-            let b = match self
-                .infcx
-                .at(&ObligationCause::dummy(), ty::ParamEnv::empty())
-                .normalize(b)
-            {
-                Ok(n) => {
-                    debug!("equate_inputs_and_outputs: {:?}", n);
-                    if n.obligations.iter().all(|o| {
-                        matches!(
-                            o.predicate.kind().skip_binder(),
-                            ty::PredicateKind::RegionOutlives(_)
-                                | ty::PredicateKind::TypeOutlives(_)
-                        )
-                    }) {
-                        n.value
-                    } else {
-                        b
-                    }
-                }
+            let b = match self.normalize_and_add_constraints(b) {
+                Ok(n) => n,
                 Err(_) => {
                     debug!("equate_inputs_and_outputs: NoSolution");
                     b
                 }
             };
+
             // Note: if we have to introduce new placeholders during normalization above, then we won't have
             // added those universes to the universe info, which we would want in `relate_tys`.
             if let Err(terr) =
@@ -207,4 +200,27 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             }
         }
     }
+
+    pub(crate) fn normalize_and_add_constraints(&mut self, t: Ty<'tcx>) -> Fallible<Ty<'tcx>> {
+        let TypeOpOutput { output: norm_ty, constraints, .. } =
+            self.param_env.and(type_op::normalize::Normalize::new(t)).fully_perform(self.infcx)?;
+
+        debug!("{:?} normalized to {:?}", t, norm_ty);
+
+        for data in constraints.into_iter().collect::<Vec<_>>() {
+            ConstraintConversion::new(
+                self.infcx,
+                &self.borrowck_context.universal_regions,
+                &self.region_bound_pairs,
+                Some(self.implicit_region_bound),
+                self.param_env,
+                Locations::All(DUMMY_SP),
+                ConstraintCategory::Internal,
+                &mut self.borrowck_context.constraints,
+            )
+            .convert_all(&*data);
+        }
+
+        Ok(norm_ty)
+    }
 }

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -893,11 +893,11 @@ struct TypeChecker<'a, 'tcx> {
 }
 
 struct BorrowCheckContext<'a, 'tcx> {
-    universal_regions: &'a UniversalRegions<'tcx>,
+    pub(crate) universal_regions: &'a UniversalRegions<'tcx>,
     location_table: &'a LocationTable,
     all_facts: &'a mut Option<AllFacts>,
     borrow_set: &'a BorrowSet<'tcx>,
-    constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
+    pub(crate) constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
     upvars: &'a [Upvar<'tcx>],
 }
 
@@ -1157,6 +1157,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         self.relate_types(sup, ty::Variance::Contravariant, sub, locations, category)
     }
 
+    #[instrument(skip(self, category), level = "debug")]
     fn eq_types(
         &mut self,
         expected: Ty<'tcx>,

compiler/rustc_infer/src/traits/util.rs

@@ -5,6 +5,7 @@ use crate::traits::{Obligation, ObligationCause, PredicateObligation};
 use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
 use rustc_middle::ty::{self, ToPredicate, TyCtxt, WithConstness};
 use rustc_span::symbol::Ident;
+use rustc_span::Span;
 
 pub fn anonymize_predicate<'tcx>(
     tcx: TyCtxt<'tcx>,
@@ -97,6 +98,22 @@ pub fn elaborate_predicates<'tcx>(
     elaborate_obligations(tcx, obligations)
 }
 
+pub fn elaborate_predicates_with_span<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    predicates: impl Iterator<Item = (ty::Predicate<'tcx>, Span)>,
+) -> Elaborator<'tcx> {
+    let obligations = predicates
+        .map(|(predicate, span)| {
+            predicate_obligation(
+                predicate,
+                ty::ParamEnv::empty(),
+                ObligationCause::dummy_with_span(span),
+            )
+        })
+        .collect();
+    elaborate_obligations(tcx, obligations)
+}
+
 pub fn elaborate_obligations<'tcx>(
     tcx: TyCtxt<'tcx>,
     mut obligations: Vec<PredicateObligation<'tcx>>,

compiler/rustc_parse/src/lexer/unescape_error_reporting.rs

@@ -82,6 +82,33 @@ pub(crate) fn emit_unescape_error(
                         Applicability::MachineApplicable,
                     );
                 }
+            } else {
+                let printable: Vec<char> = lit
+                    .chars()
+                    .filter(|&x| {
+                        unicode_width::UnicodeWidthChar::width(x).unwrap_or(0) != 0
+                            && !x.is_whitespace()
+                    })
+                    .collect();
+
+                if let [ch] = printable.as_slice() {
+                    has_help = true;
+
+                    handler.span_note(
+                        span,
+                        &format!(
+                            "there are non-printing characters, the full sequence is `{}`",
+                            lit.escape_default(),
+                        ),
+                    );
+
+                    handler.span_suggestion(
+                        span,
+                        "consider removing the non-printing characters",
+                        ch.to_string(),
+                        Applicability::MaybeIncorrect,
+                    );
+                }
             }
 
             if !has_help {

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -706,36 +706,29 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
         }
 
         let param_env = obligation.param_env;
-        let trait_ref = poly_trait_ref.skip_binder();
-
-        let found_ty = trait_ref.self_ty();
-        let found_ty_str = found_ty.to_string();
-        let imm_borrowed_found_ty = self.tcx.mk_imm_ref(self.tcx.lifetimes.re_static, found_ty);
-        let imm_substs = self.tcx.mk_substs_trait(imm_borrowed_found_ty, &[]);
-        let mut_borrowed_found_ty = self.tcx.mk_mut_ref(self.tcx.lifetimes.re_static, found_ty);
-        let mut_substs = self.tcx.mk_substs_trait(mut_borrowed_found_ty, &[]);
 
         // Try to apply the original trait binding obligation by borrowing.
-        let mut try_borrowing = |new_imm_trait_ref: ty::Binder<'tcx, ty::TraitRef<'tcx>>,
-                                 new_mut_trait_ref: ty::Binder<'tcx, ty::TraitRef<'tcx>>,
-                                 expected_trait_ref: ty::Binder<'tcx, ty::TraitRef<'tcx>>,
+        let mut try_borrowing = |old_ref: ty::Binder<'tcx, ty::TraitRef<'tcx>>,
                                  blacklist: &[DefId]|
          -> bool {
-            if blacklist.contains(&expected_trait_ref.def_id()) {
+            if blacklist.contains(&old_ref.def_id()) {
                 return false;
             }
 
-            let imm_result = self.predicate_must_hold_modulo_regions(&Obligation::new(
-                ObligationCause::dummy(),
-                param_env,
-                new_imm_trait_ref.without_const().to_predicate(self.tcx),
-            ));
-
-            let mut_result = self.predicate_must_hold_modulo_regions(&Obligation::new(
-                ObligationCause::dummy(),
-                param_env,
-                new_mut_trait_ref.without_const().to_predicate(self.tcx),
-            ));
+            let orig_ty = old_ref.self_ty().skip_binder();
+            let mk_result = |new_ty| {
+                let new_ref = old_ref.rebind(ty::TraitRef::new(
+                    old_ref.def_id(),
+                    self.tcx.mk_substs_trait(new_ty, &old_ref.skip_binder().substs[1..]),
+                ));
+                self.predicate_must_hold_modulo_regions(&Obligation::new(
+                    ObligationCause::dummy(),
+                    param_env,
+                    new_ref.without_const().to_predicate(self.tcx),
+                ))
+            };
+            let imm_result = mk_result(self.tcx.mk_imm_ref(self.tcx.lifetimes.re_static, orig_ty));
+            let mut_result = mk_result(self.tcx.mk_mut_ref(self.tcx.lifetimes.re_static, orig_ty));
 
             if imm_result || mut_result {
                 if let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span) {
@@ -747,8 +740,8 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
 
                     let msg = format!(
                         "the trait bound `{}: {}` is not satisfied",
-                        found_ty_str,
-                        expected_trait_ref.print_only_trait_path(),
+                        orig_ty.to_string(),
+                        old_ref.print_only_trait_path(),
                     );
                     if has_custom_message {
                         err.note(&msg);
@@ -764,7 +757,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
                         span,
                         &format!(
                             "expected an implementor of trait `{}`",
-                            expected_trait_ref.print_only_trait_path(),
+                            old_ref.print_only_trait_path(),
                         ),
                     );
 
@@ -807,21 +800,11 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
         };
 
         if let ObligationCauseCode::ImplDerivedObligation(obligation) = &*code {
-            let expected_trait_ref = obligation.parent_trait_ref;
-            let new_imm_trait_ref = poly_trait_ref
-                .rebind(ty::TraitRef::new(obligation.parent_trait_ref.def_id(), imm_substs));
-            let new_mut_trait_ref = poly_trait_ref
-                .rebind(ty::TraitRef::new(obligation.parent_trait_ref.def_id(), mut_substs));
-            return try_borrowing(new_imm_trait_ref, new_mut_trait_ref, expected_trait_ref, &[]);
+            try_borrowing(obligation.parent_trait_ref, &[])
         } else if let ObligationCauseCode::BindingObligation(_, _)
         | ObligationCauseCode::ItemObligation(_) = &*code
         {
-            return try_borrowing(
-                poly_trait_ref.rebind(ty::TraitRef::new(trait_ref.def_id, imm_substs)),
-                poly_trait_ref.rebind(ty::TraitRef::new(trait_ref.def_id, mut_substs)),
-                *poly_trait_ref,
-                &never_suggest_borrow[..],
-            );
+            try_borrowing(*poly_trait_ref, &never_suggest_borrow[..])
         } else {
             false
         }

compiler/rustc_trait_selection/src/traits/mod.rs

@@ -65,7 +65,8 @@ pub use self::specialize::{specialization_graph, translate_substs, OverlapError}
 pub use self::structural_match::search_for_structural_match_violation;
 pub use self::structural_match::NonStructuralMatchTy;
 pub use self::util::{
-    elaborate_obligations, elaborate_predicates, elaborate_trait_ref, elaborate_trait_refs,
+    elaborate_obligations, elaborate_predicates, elaborate_predicates_with_span,
+    elaborate_trait_ref, elaborate_trait_refs,
 };
 pub use self::util::{expand_trait_aliases, TraitAliasExpander};
 pub use self::util::{

compiler/rustc_typeck/src/check/wfcheck.rs

@@ -1641,19 +1641,38 @@ fn report_bivariance(tcx: TyCtxt<'_>, param: &rustc_hir::GenericParam<'_>) {
 
 /// Feature gates RFC 2056 -- trivial bounds, checking for global bounds that
 /// aren't true.
-fn check_false_global_bounds(fcx: &FnCtxt<'_, '_>, span: Span, id: hir::HirId) {
+fn check_false_global_bounds(fcx: &FnCtxt<'_, '_>, mut span: Span, id: hir::HirId) {
     let empty_env = ty::ParamEnv::empty();
 
     let def_id = fcx.tcx.hir().local_def_id(id);
-    let predicates = fcx.tcx.predicates_of(def_id).predicates.iter().map(|(p, _)| *p);
+    let predicates_with_span =
+        fcx.tcx.predicates_of(def_id).predicates.iter().map(|(p, span)| (*p, *span));
     // Check elaborated bounds.
-    let implied_obligations = traits::elaborate_predicates(fcx.tcx, predicates);
+    let implied_obligations = traits::elaborate_predicates_with_span(fcx.tcx, predicates_with_span);
 
     for obligation in implied_obligations {
         let pred = obligation.predicate;
         // Match the existing behavior.
         if pred.is_global(fcx.tcx) && !pred.has_late_bound_regions() {
             let pred = fcx.normalize_associated_types_in(span, pred);
+            let hir_node = fcx.tcx.hir().find(id);
+
+            // only use the span of the predicate clause (#90869)
+
+            if let Some(hir::Generics { where_clause, .. }) =
+                hir_node.and_then(|node| node.generics())
+            {
+                let obligation_span = obligation.cause.span(fcx.tcx);
+
+                span = where_clause
+                    .predicates
+                    .iter()
+                    // There seems to be no better way to find out which predicate we are in
+                    .find(|pred| pred.span().contains(obligation_span))
+                    .map(|pred| pred.span())
+                    .unwrap_or(obligation_span);
+            }
+
             let obligation = traits::Obligation::new(
                 traits::ObligationCause::new(span, id, traits::TrivialBound),
                 empty_env,

src/test/rustdoc-ui/commandline-argfile-badutf8.rs → src/test/rustdoc-ui/commandline-argfile/commandline-argfile-badutf8.rs

@@ -1,6 +1,6 @@
 // Check to see if we can get parameters from an @argsfile file
 //
-// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile-badutf8.args
+// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile/commandline-argfile-badutf8.args
 
 #[cfg(not(cmdline_set))]
 compile_error!("cmdline_set not set");

src/test/ui/commandline-argfile-missing.rs → src/test/rustdoc-ui/commandline-argfile/commandline-argfile-missing.rs

@@ -2,7 +2,7 @@
 //
 // normalize-stderr-test: "os error \d+" -> "os error $$ERR"
 // normalize-stderr-test: "commandline-argfile-missing.args:[^(]*" -> "commandline-argfile-missing.args: $$FILE_MISSING "
-// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile-missing.args
+// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile/commandline-argfile-missing.args
 
 #[cfg(not(cmdline_set))]
 compile_error!("cmdline_set not set");

src/test/rustdoc-ui/commandline-argfile.rs → src/test/rustdoc-ui/commandline-argfile/commandline-argfile.rs

@@ -1,7 +1,7 @@
 // Check to see if we can get parameters from an @argsfile file
 //
 // check-pass
-// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile.args
+// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile/commandline-argfile.args
 
 #[cfg(not(cmdline_set))]
 compile_error!("cmdline_set not set");

src/test/ui/commandline-argfile-badutf8.rs → src/test/ui/command/argfile/commandline-argfile-badutf8.rs

@@ -1,6 +1,6 @@
 // Check to see if we can get parameters from an @argsfile file
 //
-// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile-badutf8.args
+// compile-flags: --cfg cmdline_set @{{src-base}}/command/argfile/commandline-argfile-badutf8.args
 
 #[cfg(not(cmdline_set))]
 compile_error!("cmdline_set not set");

src/test/rustdoc-ui/commandline-argfile-missing.rs → src/test/ui/command/argfile/commandline-argfile-missing.rs

@@ -2,7 +2,7 @@
 //
 // normalize-stderr-test: "os error \d+" -> "os error $$ERR"
 // normalize-stderr-test: "commandline-argfile-missing.args:[^(]*" -> "commandline-argfile-missing.args: $$FILE_MISSING "
-// compile-flags: --cfg cmdline_set @{{src-base}}/commandline-argfile-missing.args
+// compile-flags: --cfg cmdline_set @{{src-base}}/command/argfile/commandline-argfile-missing.args
 
 #[cfg(not(cmdline_set))]
 compile_error!("cmdline_set not set");