1 files changed, 1 insertions, 0 deletions
diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs
index 9040cfcf54f..2894c6d29ec 100644
--- a/compiler/rustc_borrowck/src/region_infer/mod.rs
+++ b/compiler/rustc_borrowck/src/region_infer/mod.rs
@@ -1763,6 +1763,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             errors_buffer.push(RegionErrorKind::UnexpectedHiddenRegion {
                 span: m_c.definition_span,
                 hidden_ty: m_c.hidden_ty,
+                key: m_c.key,
                 member_region,
             });
         }