diff --git a/compiler/rustc_hir_analysis/src/hir_wf_check.rs b/compiler/rustc_hir_analysis/src/hir_wf_check.rs index c01b81563dc..64c1a78bd1c 100644 --- a/compiler/rustc_hir_analysis/src/hir_wf_check.rs +++ b/compiler/rustc_hir_analysis/src/hir_wf_check.rs @@ -4,7 +4,7 @@ use rustc_infer::infer::TyCtxtInferExt; use rustc_infer::traits::{ObligationCause, WellFormedLoc}; use rustc_middle::bug; use rustc_middle::query::Providers; -use rustc_middle::ty::{self, TyCtxt, TypingMode, fold_regions}; +use rustc_middle::ty::{self, TyCtxt, TypeVisitableExt, TypingMode, fold_regions}; use rustc_span::def_id::LocalDefId; use rustc_trait_selection::traits::{self, ObligationCtxt}; use tracing::debug; @@ -77,6 +77,15 @@ fn diagnostic_hir_wf_check<'tcx>( let tcx_ty = fold_regions(self.tcx, tcx_ty, |r, _| { if r.is_bound() { self.tcx.lifetimes.re_erased } else { r } }); + + // We may be checking the WFness of a type in an opaque with a non-lifetime bound. + // Perhaps we could rebind all the escaping bound vars, but they're coming from + // arbitrary debruijn indices and aren't particularly important anyways, since they + // are only coming from `feature(non_lifetime_binders)` anyways. + if tcx_ty.has_escaping_bound_vars() { + return; + } + let cause = traits::ObligationCause::new( ty.span, self.def_id, diff --git a/tests/ui/traits/non_lifetime_binders/diagnostic-hir-wf-check.rs b/tests/ui/traits/non_lifetime_binders/diagnostic-hir-wf-check.rs new file mode 100644 index 00000000000..74c23a59bee --- /dev/null +++ b/tests/ui/traits/non_lifetime_binders/diagnostic-hir-wf-check.rs @@ -0,0 +1,18 @@ +// Make sure not to construct predicates with escaping bound vars in `diagnostic_hir_wf_check`. +// Regression test for . + +#![feature(non_lifetime_binders)] +//~^ WARN the feature `non_lifetime_binders` is incomplete + +trait A {} +impl A for () {} + +trait B {} +struct W(T); + +fn b() -> (W<()>, impl for A) { (W(()), ()) } +//~^ ERROR the trait bound `(): B` is not satisfied +//~| ERROR the trait bound `(): B` is not satisfied +//~| ERROR the trait bound `(): B` is not satisfied + +fn main() {} diff --git a/tests/ui/traits/non_lifetime_binders/diagnostic-hir-wf-check.stderr b/tests/ui/traits/non_lifetime_binders/diagnostic-hir-wf-check.stderr new file mode 100644 index 00000000000..df99f4a67ab --- /dev/null +++ b/tests/ui/traits/non_lifetime_binders/diagnostic-hir-wf-check.stderr @@ -0,0 +1,65 @@ +warning: the feature `non_lifetime_binders` is incomplete and may not be safe to use and/or cause compiler crashes + --> $DIR/diagnostic-hir-wf-check.rs:4:12 + | +LL | #![feature(non_lifetime_binders)] + | ^^^^^^^^^^^^^^^^^^^^ + | + = note: see issue #108185 for more information + = note: `#[warn(incomplete_features)]` on by default + +error[E0277]: the trait bound `(): B` is not satisfied + --> $DIR/diagnostic-hir-wf-check.rs:13:12 + | +LL | fn b() -> (W<()>, impl for A) { (W(()), ()) } + | ^^^^^ the trait `B` is not implemented for `()` + | +help: this trait has no implementations, consider adding one + --> $DIR/diagnostic-hir-wf-check.rs:10:1 + | +LL | trait B {} + | ^^^^^^^ +note: required by a bound in `W` + --> $DIR/diagnostic-hir-wf-check.rs:11:13 + | +LL | struct W(T); + | ^ required by this bound in `W` + +error[E0277]: the trait bound `(): B` is not satisfied + --> $DIR/diagnostic-hir-wf-check.rs:13:42 + | +LL | fn b() -> (W<()>, impl for A) { (W(()), ()) } + | - ^^ the trait `B` is not implemented for `()` + | | + | required by a bound introduced by this call + | +help: this trait has no implementations, consider adding one + --> $DIR/diagnostic-hir-wf-check.rs:10:1 + | +LL | trait B {} + | ^^^^^^^ +note: required by a bound in `W` + --> $DIR/diagnostic-hir-wf-check.rs:11:13 + | +LL | struct W(T); + | ^ required by this bound in `W` + +error[E0277]: the trait bound `(): B` is not satisfied + --> $DIR/diagnostic-hir-wf-check.rs:13:40 + | +LL | fn b() -> (W<()>, impl for A) { (W(()), ()) } + | ^^^^^ the trait `B` is not implemented for `()` + | +help: this trait has no implementations, consider adding one + --> $DIR/diagnostic-hir-wf-check.rs:10:1 + | +LL | trait B {} + | ^^^^^^^ +note: required by a bound in `W` + --> $DIR/diagnostic-hir-wf-check.rs:11:13 + | +LL | struct W(T); + | ^ required by this bound in `W` + +error: aborting due to 3 previous errors; 1 warning emitted + +For more information about this error, try `rustc --explain E0277`.