diff --git a/jerry-core/parser/js/js-parser.c b/jerry-core/parser/js/js-parser.c
index ac5aa559e..472fe63e3 100644
--- a/jerry-core/parser/js/js-parser.c
+++ b/jerry-core/parser/js/js-parser.c
@@ -2291,6 +2291,7 @@ parser_parse_function (parser_context_t *context_p, /**< context */
   if ((context_p->status_flags & (PARSER_CLASS_CONSTRUCTOR | PARSER_ALLOW_SUPER_CALL)) == PARSER_CLASS_CONSTRUCTOR)
   {
     parser_emit_cbc_ext (context_p, CBC_EXT_RUN_FIELD_INIT);
+    parser_flush_cbc (context_p);
   }
 #endif /* ENABLED (JERRY_ESNEXT) */
 
diff --git a/tests/jerry/regression-test-issue-4238.js b/tests/jerry/regression-test-issue-4238.js
new file mode 100644
index 000000000..6e0fb4985
--- /dev/null
+++ b/tests/jerry/regression-test-issue-4238.js
@@ -0,0 +1,24 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+try {
+    eval(" \
+    class foo { \
+        constructor() { \
+            function bar() {} \
+        } \
+    ")
+} catch (e) {
+    assert (e instanceof SyntaxError)
+}