diff --git a/Python/optimizer_bytecodes.c b/Python/optimizer_bytecodes.c
index 4bdef60dda9d53..ea7c39bd01ea07 100644
--- a/Python/optimizer_bytecodes.c
+++ b/Python/optimizer_bytecodes.c
@@ -166,7 +166,7 @@ dummy_func(void) {
             REPLACE_OP(this_instr, _NOP, 0 ,0);
         }
         sym_set_type(left, &PyUnicode_Type);
-        sym_set_type(left, &PyUnicode_Type);
+        sym_set_type(right, &PyUnicode_Type);
     }
 
     op(_BINARY_OP, (left, right -- res)) {
diff --git a/Python/optimizer_cases.c.h b/Python/optimizer_cases.c.h
index 306599bea77877..9f3fc052494309 100644
--- a/Python/optimizer_cases.c.h
+++ b/Python/optimizer_cases.c.h
@@ -513,7 +513,7 @@
                 REPLACE_OP(this_instr, _NOP, 0 ,0);
             }
             sym_set_type(left, &PyUnicode_Type);
-            sym_set_type(left, &PyUnicode_Type);
+            sym_set_type(right, &PyUnicode_Type);
             break;
         }