1 files changed, 14 insertions, 9 deletions

diff --git a/crates/ra_hir/src/ty/infer/unify.rs b/crates/ra_hir/src/ty/infer/unify.rs
index d161aa6b3..ca33cc7f8 100644
--- a/crates/ra_hir/src/ty/infer/unify.rs
+++ b/crates/ra_hir/src/ty/infer/unify.rs
@@ -6,6 +6,7 @@ use crate::ty::{
     Canonical, InEnvironment, InferTy, ProjectionPredicate, ProjectionTy, Substs, TraitRef, Ty,
     TypeWalk,
 };
+use crate::util::make_mut_slice;
 
 impl<'a, D: HirDatabase> InferenceContext<'a, D> {
     pub(super) fn canonicalizer<'b>(&'b mut self) -> Canonicalizer<'a, 'b, D>
@@ -53,7 +54,9 @@ where
                     // recursive type
                     return tv.fallback_value();
                 }
-                if let Some(known_ty) = self.ctx.var_unification_table.probe_value(inner).known() {
+                if let Some(known_ty) =
+                    self.ctx.var_unification_table.inlined_probe_value(inner).known()
+                {
                     self.var_stack.push(inner);
                     let result = self.do_canonicalize_ty(known_ty.clone());
                     self.var_stack.pop();
@@ -74,10 +77,11 @@ where
         })
     }
 
-    fn do_canonicalize_trait_ref(&mut self, trait_ref: TraitRef) -> TraitRef {
-        let substs =
-            trait_ref.substs.iter().map(|ty| self.do_canonicalize_ty(ty.clone())).collect();
-        TraitRef { trait_: trait_ref.trait_, substs: Substs(substs) }
+    fn do_canonicalize_trait_ref(&mut self, mut trait_ref: TraitRef) -> TraitRef {
+        for ty in make_mut_slice(&mut trait_ref.substs.0) {
+            *ty = self.do_canonicalize_ty(ty.clone());
+        }
+        trait_ref
     }
 
     fn into_canonicalized<T>(self, result: T) -> Canonicalized<T> {
@@ -87,10 +91,11 @@ where
         }
     }
 
-    fn do_canonicalize_projection_ty(&mut self, projection_ty: ProjectionTy) -> ProjectionTy {
-        let params =
-            projection_ty.parameters.iter().map(|ty| self.do_canonicalize_ty(ty.clone())).collect();
-        ProjectionTy { associated_ty: projection_ty.associated_ty, parameters: Substs(params) }
+    fn do_canonicalize_projection_ty(&mut self, mut projection_ty: ProjectionTy) -> ProjectionTy {
+        for ty in make_mut_slice(&mut projection_ty.parameters.0) {
+            *ty = self.do_canonicalize_ty(ty.clone());
+        }
+        projection_ty
     }
 
     fn do_canonicalize_projection_predicate(