From 10f9f14377a2fdf65a1f07497c48ce264816a04a Mon Sep 17 00:00:00 2001 From: Dnreikronos Date: Mon, 1 Jun 2026 13:47:30 -0300 Subject: [PATCH 1/3] Build a fully-applied trait ref in method-not-found suggestion When a method call fails to resolve, the suggestion machinery probes all traits for a method with the same name and builds a trait reference for the providing trait to detect duplicate trait items coming from multiple crate versions. It passed only the receiver type as the single argument, which is correct only for traits whose sole generic parameter is `Self`. For a trait with further parameters (for example `Borrow`), or when the receiver type is unknown, the argument list no longer matched the trait's generics and tripped the `debug_assert_args_compatible` assertion, producing an ICE. Build the argument list with `GenericArgs::for_item` instead, using the receiver type for `Self` when known and fresh inference variables for the remaining parameters. --- .../rustc_hir_typeck/src/method/suggest.rs | 19 +++++- ...estion-trait-with-extra-generics-no-ice.rs | 24 +++++++ ...on-trait-with-extra-generics-no-ice.stderr | 65 +++++++++++++++++++ 3 files changed, 107 insertions(+), 1 deletion(-) create mode 100644 tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.rs create mode 100644 tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.stderr diff --git a/compiler/rustc_hir_typeck/src/method/suggest.rs b/compiler/rustc_hir_typeck/src/method/suggest.rs index c9ec32159f476..48e1f553900b0 100644 --- a/compiler/rustc_hir_typeck/src/method/suggest.rs +++ b/compiler/rustc_hir_typeck/src/method/suggest.rs @@ -4796,7 +4796,24 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { let hir::Node::Expr(rcvr) = self.tcx.hir_node(hir_id) else { return false; }; - let trait_ref = ty::TraitRef::new(self.tcx, trait_def_id, rcvr_ty.into_iter()); + // The trait may have generic parameters beyond `Self` (e.g. `Borrow`), and + // `rcvr_ty` may even be unknown. We only ever know the receiver type (the `Self` arg), + // so fill `Self` from `rcvr_ty` when available and the remaining parameters with fresh + // inference variables; building a `TraitRef` with a partial arg list would otherwise trip + // `debug_assert_args_compatible` and ICE. See #157189. + let trait_ref = ty::TraitRef::new_from_args( + self.tcx, + trait_def_id, + ty::GenericArgs::for_item(self.tcx, trait_def_id, |param, _| { + if param.index == 0 + && let Some(rcvr_ty) = rcvr_ty + { + rcvr_ty.into() + } else { + self.var_for_def(rcvr.span, param) + } + }), + ); let trait_pred = ty::Binder::dummy(ty::TraitPredicate { trait_ref, polarity: ty::PredicatePolarity::Positive, diff --git a/tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.rs b/tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.rs new file mode 100644 index 0000000000000..0a98cdef5c923 --- /dev/null +++ b/tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.rs @@ -0,0 +1,24 @@ +//! Regression test for #157189. +//! +//! When a method call fails to resolve, the "trait which provides `` is +//! implemented but not in scope" diagnostic probes all traits for a method of the +//! same name. Here `.borrow()` matches `std::borrow::Borrow::borrow`, and `Borrow` +//! has a generic parameter (`Borrowed`) besides `Self`. Building the trait +//! reference for the diagnostic used to pass only the receiver type as the single +//! argument, which mismatched the trait's generics and ICEd in +//! `debug_assert_args_compatible`. It should just report the error. + +trait Foo { + extern "C" fn borrow(&self); +} + +struct Bar; + +fn main() { + let foo: Box usize> = Box::new(Bar); + //~^ ERROR expected a `Fn(bool)` closure, found `Bar` + foo.borrow(); + //~^ ERROR no method named `borrow` found + foo.take() + //~^ ERROR `Box usize>` is not an iterator +} diff --git a/tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.stderr b/tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.stderr new file mode 100644 index 0000000000000..aa46a41fa3378 --- /dev/null +++ b/tests/ui/methods/method-suggestion-trait-with-extra-generics-no-ice.stderr @@ -0,0 +1,65 @@ +error[E0599]: no method named `borrow` found for struct `Box usize>` in the current scope + --> $DIR/method-suggestion-trait-with-extra-generics-no-ice.rs:20:9 + | +LL | foo.borrow(); + | ^^^^^^ + | + --> $SRC_DIR/core/src/borrow.rs:LL:COL + | + = note: the method is available for `Box usize>` here + | + = help: items from traits can only be used if the trait is in scope +help: use parentheses to call this trait object + | +LL | foo(/* bool */).borrow(); + | ++++++++++++ +help: trait `Borrow` which provides `borrow` is implemented but not in scope; perhaps you want to import it + | +LL + use std::borrow::Borrow; + | +help: there is a method `borrow_mut` with a similar name + | +LL | foo.borrow_mut(); + | ++++ + +error[E0277]: expected a `Fn(bool)` closure, found `Bar` + --> $DIR/method-suggestion-trait-with-extra-generics-no-ice.rs:18:43 + | +LL | let foo: Box usize> = Box::new(Bar); + | ^^^^^^^^^^^^^ expected an `Fn(bool)` closure, found `Bar` + | +help: the trait `Fn(bool)` is not implemented for `Bar` + --> $DIR/method-suggestion-trait-with-extra-generics-no-ice.rs:15:1 + | +LL | struct Bar; + | ^^^^^^^^^^ + = note: required for the cast from `Box` to `Box usize>` + +error[E0599]: `Box usize>` is not an iterator + --> $DIR/method-suggestion-trait-with-extra-generics-no-ice.rs:22:9 + | +LL | foo.take() + | ^^^^ + | | + | this is an associated function, not a method + | `Box usize>` is not an iterator + | + = note: found the following associated functions; to be used as methods, functions must have a `self` parameter + = note: the candidate is defined in an impl for the type `Box` + = note: the following trait bounds were not satisfied: + `dyn Fn(bool) -> usize: Iterator` + which is required by `Box usize>: Iterator` + `Box usize>: Iterator` + which is required by `&mut Box usize>: Iterator` + `dyn Fn(bool) -> usize: Iterator` + which is required by `&mut dyn Fn(bool) -> usize: Iterator` +help: use associated function syntax instead + | +LL - foo.take() +LL + Box:: usize>::take(foo) + | + +error: aborting due to 3 previous errors + +Some errors have detailed explanations: E0277, E0599. +For more information about an error, try `rustc --explain E0277`. From f25f4b459c38678d56b1d0624b4856e9a35c891d Mon Sep 17 00:00:00 2001 From: Jieyou Xu Date: Fri, 5 Jun 2026 22:41:18 +0800 Subject: [PATCH 2/3] compiletest: inject `#![windows_subsystem = "windows"]` to debuginfo tests on Windows So that we don't get a bunch of console windows spawned by the debugger processes. --- src/tools/compiletest/src/runtest.rs | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs index 72817ad64521a..79e04b12fbed3 100644 --- a/src/tools/compiletest/src/runtest.rs +++ b/src/tools/compiletest/src/runtest.rs @@ -1645,6 +1645,11 @@ impl<'test> TestCx<'test> { if self.config.mode == TestMode::CodegenUnits { compiler.args(&["-Z", "human_readable_cgu_names"]); } + + if self.config.mode == TestMode::DebugInfo && cfg!(target_os = "windows") { + // Prevent debugger processes from creating new console windows. + compiler.args(&["-Z", r#"crate-attr=windows_subsystem="windows""#]); + } } if self.config.optimize_tests && compiler_kind == CompilerKind::Rustc { From 36742d886762365ad22152d8ddcf311ed58968cf Mon Sep 17 00:00:00 2001 From: Egor Ivanov Date: Fri, 5 Jun 2026 17:04:12 +0000 Subject: [PATCH 3/3] Convert `QueryRegionConstraint` into a struct --- .../src/type_check/constraint_conversion.rs | 8 ++-- .../src/infer/canonical/query_response.rs | 43 ++++++++++++------- compiler/rustc_middle/src/infer/canonical.rs | 9 ++-- .../src/solve/delegate.rs | 5 ++- .../src/traits/outlives_bounds.rs | 3 +- .../rustc_traits/src/coroutine_witnesses.rs | 3 +- 6 files changed, 45 insertions(+), 26 deletions(-) diff --git a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs index bca2de041b657..4d93fa08fe0bd 100644 --- a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs +++ b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs @@ -1,7 +1,7 @@ use rustc_data_structures::fx::FxHashSet; use rustc_hir::def_id::LocalDefId; use rustc_infer::infer::SubregionOrigin; -use rustc_infer::infer::canonical::QueryRegionConstraints; +use rustc_infer::infer::canonical::{QueryRegionConstraint, QueryRegionConstraints}; use rustc_infer::infer::outlives::env::RegionBoundPairs; use rustc_infer::infer::outlives::obligations::{TypeOutlives, TypeOutlivesDelegate}; use rustc_infer::infer::region_constraints::{GenericKind, VerifyBound}; @@ -74,9 +74,9 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { let assumptions = elaborate::elaborate_outlives_assumptions(self.infcx.tcx, assumptions.iter().copied()); - for &(constraint, constraint_category, _) in constraints { + for &QueryRegionConstraint { constraint, category, .. } in constraints { constraint.iter_outlives().for_each(|predicate| { - self.convert(predicate, constraint_category, &assumptions); + self.convert(predicate, category, &assumptions); }); } } @@ -296,7 +296,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> { // FIXME(higher_ranked_auto): What should we do with the assumptions here? if let Some(QueryRegionConstraints { constraints, assumptions: _ }) = constraints { next_outlives_predicates.extend(constraints.iter().flat_map( - |(constraint, category, _)| { + |QueryRegionConstraint { constraint, category, .. }| { constraint.iter_outlives().map(|outlives| (outlives, *category)) }, )); diff --git a/compiler/rustc_infer/src/infer/canonical/query_response.rs b/compiler/rustc_infer/src/infer/canonical/query_response.rs index 98763ff742f25..5641523c304c9 100644 --- a/compiler/rustc_infer/src/infer/canonical/query_response.rs +++ b/compiler/rustc_infer/src/infer/canonical/query_response.rs @@ -13,7 +13,7 @@ use std::iter; use rustc_index::{Idx, IndexVec}; use rustc_middle::arena::ArenaAllocatable; use rustc_middle::bug; -use rustc_middle::infer::canonical::CanonicalVarKind; +use rustc_middle::infer::canonical::{CanonicalVarKind, QueryRegionConstraint}; use rustc_middle::ty::{self, BoundVar, GenericArg, GenericArgKind, Ty, TyCtxt, TypeFoldable}; use tracing::{debug, instrument}; @@ -188,7 +188,9 @@ impl<'tcx> InferCtxt<'tcx> { let InferOk { value: result_args, obligations } = self.query_response_instantiation(cause, param_env, original_values, query_response)?; - for (constraint, _category, vis) in &query_response.value.region_constraints.constraints { + for QueryRegionConstraint { constraint, visible_for_leak_check: vis, .. } in + &query_response.value.region_constraints.constraints + { let constraint = instantiate_value(self.tcx, &result_args, *constraint); match constraint { ty::RegionConstraint::Outlives(predicate) => { @@ -285,11 +287,12 @@ impl<'tcx> InferCtxt<'tcx> { (GenericArgKind::Lifetime(v_o), GenericArgKind::Lifetime(v_r)) => { if v_o != v_r { - output_query_region_constraints.constraints.push(( - ty::RegionEqPredicate(v_o, v_r).into(), - constraint_category, - ty::VisibleForLeakCheck::Yes, - )); + let constraint = QueryRegionConstraint { + constraint: ty::RegionEqPredicate(v_o, v_r).into(), + category: constraint_category, + visible_for_leak_check: ty::VisibleForLeakCheck::Yes, + }; + output_query_region_constraints.constraints.push(constraint); } } @@ -321,7 +324,7 @@ impl<'tcx> InferCtxt<'tcx> { let r_c = instantiate_value(self.tcx, &result_args, r_c); // Screen out `'a: 'a` or `'a == 'a` cases. - if r_c.0.is_trivial() { None } else { Some(r_c) } + if r_c.constraint.is_trivial() { None } else { Some(r_c) } }), ); @@ -616,7 +619,7 @@ pub fn make_query_region_constraints<'tcx>( debug!(?constraints); - let constraints: Vec<_> = constraints + let constraints: Vec> = constraints .iter() .map(|(c, origin)| match c.kind { ConstraintKind::VarSubVar @@ -625,22 +628,30 @@ pub fn make_query_region_constraints<'tcx>( | ConstraintKind::RegSubReg => { // Swap regions because we are going from sub (<=) to outlives (>=). let constraint = ty::OutlivesPredicate(c.sup.into(), c.sub).into(); - (constraint, origin.to_constraint_category(), c.visible_for_leak_check) + QueryRegionConstraint { + constraint, + category: origin.to_constraint_category(), + visible_for_leak_check: c.visible_for_leak_check, + } } ConstraintKind::VarEqVar | ConstraintKind::VarEqReg | ConstraintKind::RegEqReg => { let constraint = ty::RegionEqPredicate(c.sup, c.sub).into(); - (constraint, origin.to_constraint_category(), c.visible_for_leak_check) + QueryRegionConstraint { + constraint, + category: origin.to_constraint_category(), + visible_for_leak_check: c.visible_for_leak_check, + } } }) .chain(outlives_obligations.into_iter().map( |TypeOutlivesConstraint { sub_region, sup_type, origin }| { - ( - ty::OutlivesPredicate(sup_type.into(), sub_region).into(), - origin.to_constraint_category(), + QueryRegionConstraint { + constraint: ty::OutlivesPredicate(sup_type.into(), sub_region).into(), + category: origin.to_constraint_category(), // We don't do leak checks for type outlives - ty::VisibleForLeakCheck::Unreachable, - ) + visible_for_leak_check: ty::VisibleForLeakCheck::Unreachable, + } }, )) .collect(); diff --git a/compiler/rustc_middle/src/infer/canonical.rs b/compiler/rustc_middle/src/infer/canonical.rs index ee8ab8a2ff931..8f182d096e759 100644 --- a/compiler/rustc_middle/src/infer/canonical.rs +++ b/compiler/rustc_middle/src/infer/canonical.rs @@ -135,9 +135,12 @@ impl<'tcx, R> QueryResponse<'tcx, R> { } } -// FIXME: Convert this into a struct -pub type QueryRegionConstraint<'tcx> = - (ty::RegionConstraint<'tcx>, ConstraintCategory<'tcx>, ty::VisibleForLeakCheck); +#[derive(Debug, StableHash, Hash, Eq, PartialEq, TypeVisitable, Clone, TypeFoldable, Copy)] +pub struct QueryRegionConstraint<'tcx> { + pub constraint: ty::RegionConstraint<'tcx>, + pub category: ConstraintCategory<'tcx>, + pub visible_for_leak_check: ty::VisibleForLeakCheck, +} #[derive(Default)] pub struct CanonicalParamEnvCache<'tcx> { diff --git a/compiler/rustc_trait_selection/src/solve/delegate.rs b/compiler/rustc_trait_selection/src/solve/delegate.rs index bd22ba6b6bf6d..7c2f5c7f170aa 100644 --- a/compiler/rustc_trait_selection/src/solve/delegate.rs +++ b/compiler/rustc_trait_selection/src/solve/delegate.rs @@ -7,6 +7,7 @@ use rustc_hir::def_id::{CRATE_DEF_ID, DefId}; use rustc_infer::infer::canonical::query_response::make_query_region_constraints; use rustc_infer::infer::canonical::{ Canonical, CanonicalExt as _, CanonicalQueryInput, CanonicalVarKind, CanonicalVarValues, + QueryRegionConstraint, }; use rustc_infer::infer::{InferCtxt, RegionVariableOrigin, SubregionOrigin, TyCtxtInferExt}; use rustc_infer::traits::solve::{FetchEligibleAssocItemResponse, Goal}; @@ -262,7 +263,9 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate< let mut seen = FxHashMap::default(); let mut constraints = vec![]; - for (outlives, _, vis) in region_constraints.constraints { + for QueryRegionConstraint { constraint: outlives, visible_for_leak_check: vis, .. } in + region_constraints.constraints + { match seen.entry(outlives) { Entry::Occupied(occupied) => { let idx = occupied.get(); diff --git a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs index 8be26fed0ca42..a171a0de9dd79 100644 --- a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs +++ b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs @@ -1,4 +1,5 @@ use rustc_infer::infer::InferOk; +use rustc_infer::infer::canonical::QueryRegionConstraint; use rustc_infer::infer::resolve::OpportunisticRegionResolver; use rustc_infer::traits::query::type_op::ImpliedOutlivesBounds; use rustc_macros::extension; @@ -83,7 +84,7 @@ fn implied_outlives_bounds<'a, 'tcx>( // outlives bound required proving some higher-ranked coroutine obl. let QueryRegionConstraints { constraints, assumptions: _ } = constraints; let cause = ObligationCause::misc(span, body_id); - for &(constraint, _, vis) in &constraints { + for &QueryRegionConstraint { constraint, visible_for_leak_check: vis, .. } in &constraints { match constraint { ty::RegionConstraint::Outlives(predicate) => { infcx.register_outlives_constraint(predicate, vis, &cause) diff --git a/compiler/rustc_traits/src/coroutine_witnesses.rs b/compiler/rustc_traits/src/coroutine_witnesses.rs index 83a77f17b28ce..7fe8303b7459b 100644 --- a/compiler/rustc_traits/src/coroutine_witnesses.rs +++ b/compiler/rustc_traits/src/coroutine_witnesses.rs @@ -1,4 +1,5 @@ use rustc_infer::infer::TyCtxtInferExt; +use rustc_infer::infer::canonical::QueryRegionConstraint; use rustc_infer::infer::canonical::query_response::make_query_region_constraints; use rustc_infer::infer::resolve::OpportunisticRegionResolver; use rustc_infer::traits::{Obligation, ObligationCause}; @@ -80,7 +81,7 @@ fn compute_assumptions<'tcx>( tcx.mk_outlives_from_iter( constraints .into_iter() - .flat_map(|(constraint, _, _)| constraint.iter_outlives()) + .flat_map(|QueryRegionConstraint { constraint, .. }| constraint.iter_outlives()) // FIXME(higher_ranked_auto): We probably should deeply resolve these before // filtering out infers which only correspond to unconstrained infer regions // which we can sometimes get.