1 files changed, 3 insertions, 3 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 563cc257e03..0a1e971f268 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -1170,11 +1170,11 @@ fn opt_normalize_projection_type<'a, 'b, 'tcx>(
             };
 
             let mut deduped: SsoHashSet<_> = Default::default();
-            result.obligations.drain_filter(|projected_obligation| {
+            result.obligations.retain(|projected_obligation| {
                 if !deduped.insert(projected_obligation.clone()) {
-                    return true;
+                    return false;
                 }
-                false
+                true
             });
 
             if use_cache {