diff --git a/compiler/rustc_const_eval/src/interpret/validity.rs b/compiler/rustc_const_eval/src/interpret/validity.rs
index 702954884a08..905ab6cb578f 100644
--- a/compiler/rustc_const_eval/src/interpret/validity.rs
+++ b/compiler/rustc_const_eval/src/interpret/validity.rs
@@ -600,7 +600,7 @@ fn try_visit_primitive(
                 self.check_safe_pointer(&ptr, "box")?;
 
                 // Check other fields of Box
-                self.walk_value(op)?;
+                self.walk_value(value)?;
                 Ok(true)
             }
             ty::FnPtr(_sig) => {