diff --git a/gen/function_source.c b/gen/function_source.c
index 642e828..f486ee5 100644
Binary files a/gen/function_source.c and b/gen/function_source.c differ
diff --git a/gen/hello.c b/gen/hello.c
index f713ed1..8c0f251 100644
Binary files a/gen/hello.c and b/gen/hello.c differ
diff --git a/gen/hello_module.c b/gen/hello_module.c
index 45e9bc7..65cd2e7 100644
Binary files a/gen/hello_module.c and b/gen/hello_module.c differ
diff --git a/gen/repl.c b/gen/repl.c
index 80bf563..b79df84 100644
Binary files a/gen/repl.c and b/gen/repl.c differ
diff --git a/gen/standalone.c b/gen/standalone.c
index 39f0a65..998907a 100644
Binary files a/gen/standalone.c and b/gen/standalone.c differ
diff --git a/gen/test_fib.c b/gen/test_fib.c
index d33cff2..efa478d 100644
Binary files a/gen/test_fib.c and b/gen/test_fib.c differ
diff --git a/quickjs-opcode.h b/quickjs-opcode.h
index 09dacb3..fb5394c 100644
--- a/quickjs-opcode.h
+++ b/quickjs-opcode.h
@@ -111,6 +111,7 @@ DEF(         return, 1, 1, 0, none)
 DEF(   return_undef, 1, 0, 0, none)
 DEF(check_ctor_return, 1, 1, 2, none)
 DEF(     check_ctor, 1, 0, 0, none)
+DEF(      init_ctor, 1, 0, 1, none)
 DEF(    check_brand, 1, 2, 2, none) /* this_obj func -> this_obj func */
 DEF(      add_brand, 1, 2, 0, none) /* this_obj home_obj -> */
 DEF(   return_async, 1, 1, 0, none)
diff --git a/quickjs.c b/quickjs.c
index 9b86e42..c534a26 100644
--- a/quickjs.c
+++ b/quickjs.c
@@ -15412,10 +15412,27 @@ static JSValue JS_CallInternal(JSContext *caller_ctx, JSValue func_obj,
             BREAK;
         CASE(OP_check_ctor):
             if (JS_IsUndefined(new_target)) {
+            non_ctor_call:
                 JS_ThrowTypeError(ctx, "class constructors must be invoked with 'new'");
                 goto exception;
             }
             BREAK;
+        CASE(OP_init_ctor):
+            {
+                JSValue super, ret;
+                sf->cur_pc = pc;
+                if (JS_IsUndefined(new_target))
+                    goto non_ctor_call;
+                super = JS_GetPrototype(ctx, func_obj);
+                if (JS_IsException(super))
+                    goto exception;
+                ret = JS_CallConstructor2(ctx, super, new_target, argc, argv);
+                JS_FreeValue(ctx, super);
+                if (JS_IsException(ret))
+                    goto exception;
+                *sp++ = ret;
+            }
+            BREAK;
         CASE(OP_check_brand):
             {
                 int ret = JS_CheckBrand(ctx, sp[-2], sp[-1]);
@@ -21896,9 +21913,6 @@ static __exception int js_parse_class_default_ctor(JSParseState *s,
     fd->has_this_binding = TRUE;
     fd->new_target_allowed = TRUE;
 
-    /* error if not invoked as a constructor */
-    emit_op(s, OP_check_ctor);
-
     push_scope(s);  /* enter body scope */
     fd->body_scope = fd->scope_level;
     if (has_super) {
@@ -21906,43 +21920,17 @@ static __exception int js_parse_class_default_ctor(JSParseState *s,
         fd->super_call_allowed = TRUE;
         fd->arguments_allowed = TRUE;
         fd->has_arguments_binding = TRUE;
-
         func_type = JS_PARSE_FUNC_DERIVED_CLASS_CONSTRUCTOR;
-        /* super */
-        emit_op(s, OP_scope_get_var);
-        emit_atom(s, JS_ATOM_this_active_func);
-        emit_u16(s, 0);
-
-        emit_op(s, OP_get_super);
-
-        emit_op(s, OP_scope_get_var);
-        emit_atom(s, JS_ATOM_new_target);
-        emit_u16(s, 0);
-
-        emit_op(s, OP_array_from);
-        emit_u16(s, 0);
-        emit_op(s, OP_push_i32);
-        emit_u32(s, 0);
-
-        /* arguments */
-        emit_op(s, OP_scope_get_var);
-        emit_atom(s, JS_ATOM_arguments);
-        emit_u16(s, 0);
-
-        emit_op(s, OP_append);
-        /* drop the index */
-        emit_op(s, OP_drop);
-
-        emit_op(s, OP_apply);
-        emit_u16(s, 1);
-        /* set the 'this' value */
-        emit_op(s, OP_dup);
+        emit_op(s, OP_init_ctor);
+        // TODO(bnoordhuis) roll into OP_init_ctor
         emit_op(s, OP_scope_put_var_init);
         emit_atom(s, JS_ATOM_this);
         emit_u16(s, 0);
         emit_class_field_init(s);
     } else {
         func_type = JS_PARSE_FUNC_CLASS_CONSTRUCTOR;
+        /* error if not invoked as a constructor */
+        emit_op(s, OP_check_ctor);
         emit_class_field_init(s);
     }