2 files changed, 5 insertions, 0 deletions
diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs
index f46c596425b..2cfa447833c 100644
--- a/compiler/rustc_infer/src/infer/mod.rs
+++ b/compiler/rustc_infer/src/infer/mod.rs
@@ -587,6 +587,7 @@ pub enum FixupError {
     UnresolvedFloatTy(FloatVid),
     UnresolvedTy(TyVid),
     UnresolvedConst(ConstVid),
+    UnresolvedEffect(EffectVid),
 }
 
 /// See the `region_obligations` field for more information.
@@ -614,6 +615,7 @@ impl fmt::Display for FixupError {
             ),
             UnresolvedTy(_) => write!(f, "unconstrained type"),
             UnresolvedConst(_) => write!(f, "unconstrained const value"),
+            UnresolvedEffect(_) => write!(f, "unconstrained effect value"),
         }
     }
 }
diff --git a/compiler/rustc_infer/src/infer/resolve.rs b/compiler/rustc_infer/src/infer/resolve.rs
index 21ef2e89523..830d79f52b9 100644
--- a/compiler/rustc_infer/src/infer/resolve.rs
+++ b/compiler/rustc_infer/src/infer/resolve.rs
@@ -167,6 +167,9 @@ impl<'a, 'tcx> FallibleTypeFolder<TyCtxt<'tcx>> for FullTypeResolver<'a, 'tcx> {
                 ty::ConstKind::Infer(InferConst::Fresh(_)) => {
                     bug!("Unexpected const in full const resolver: {:?}", c);
                 }
+                ty::ConstKind::Infer(InferConst::EffectVar(evid)) => {
+                    return Err(FixupError::UnresolvedEffect(evid));
+                }
                 _ => {}
             }
             c.try_super_fold_with(self)