diff --git a/passes/techmap/abc9.cc b/passes/techmap/abc9.cc
index df14f8f7e..7255e2481 100644
--- a/passes/techmap/abc9.cc
+++ b/passes/techmap/abc9.cc
@@ -1263,10 +1263,11 @@ struct Abc9Pass : public Pass {
 			}
 		}
 
-		Pass::call(design, "clean");
-
 		assign_map.clear();
 
+		// The "clean" pass also contains a design->check() call
+		Pass::call(design, "clean");
+
 		log_pop();
 	}
 } Abc9Pass;