diff --git a/crates/hir/src/semantics.rs b/crates/hir/src/semantics.rs
index 247d640697..117d9c4920 100644
--- a/crates/hir/src/semantics.rs
+++ b/crates/hir/src/semantics.rs
@@ -147,7 +147,7 @@ impl TypeInfo {
 }
 
 /// Primary API to get semantic information, like types, from syntax trees.
-pub struct Semantics<'db, DB> {
+pub struct Semantics<'db, DB: ?Sized> {
     pub db: &'db DB,
     imp: SemanticsImpl<'db>,
 }