diff options
3 files changed, 26 insertions, 3 deletions
diff --git a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs index b35e76b96ad..4eb7be542e7 100644 --- a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs +++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs @@ -124,7 +124,22 @@ impl<'tcx> RegionInferenceContext<'tcx> { ty::ReVar(vid) => { // Find something that we can name let upper_bound = self.approx_universal_upper_bound(vid); - self.definitions[upper_bound].external_name.unwrap_or(region) + let upper_bound = &self.definitions[upper_bound]; + match upper_bound.external_name { + Some(reg) => reg, + None => { + // Nothing exact found, so we pick the first one that we find. + let scc = self.constraint_sccs.scc(vid); + for vid in self.rev_scc_graph.as_ref().unwrap().upper_bounds(scc) { + match self.definitions[vid].external_name { + None => {} + Some(&ty::ReStatic) => {} + Some(region) => return region, + } + } + region + } + } } _ => region, }) diff --git a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.nll.stderr b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.nll.stderr index 8cf89f164b1..0fe9b06355f 100644 --- a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.nll.stderr +++ b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.nll.stderr @@ -4,7 +4,11 @@ error[E0700]: hidden type for `impl Trait` captures lifetime that does not appea LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'d, 'e> | ^^^^^^^^^^^^^^^^^^ | - = note: hidden type `Ordinary<'_>` captures lifetime '_#9r +note: hidden type `Ordinary<'b>` captures the lifetime `'b` as defined on the function body at 16:21 + --> $DIR/ordinary-bounds-unrelated.rs:16:21 + | +LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'d, 'e> + | ^^ error: aborting due to previous error diff --git a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.nll.stderr b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.nll.stderr index 1bcb28120ed..6de77523db5 100644 --- a/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.nll.stderr +++ b/src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.nll.stderr @@ -4,7 +4,11 @@ error[E0700]: hidden type for `impl Trait` captures lifetime that does not appea LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a, 'b> | ^^^^^^^^^^^^^^^^^^ | - = note: hidden type `Ordinary<'_>` captures lifetime '_#6r +note: hidden type `Ordinary<'b>` captures the lifetime `'b` as defined on the function body at 18:21 + --> $DIR/ordinary-bounds-unsuited.rs:18:21 + | +LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a, 'b> + | ^^ error: aborting due to previous error |