diff --git a/Zend/zend_vm_def.h b/Zend/zend_vm_def.h
index 55675e4a0b5c2..9451b3e4d1b24 100644
--- a/Zend/zend_vm_def.h
+++ b/Zend/zend_vm_def.h
@@ -4003,6 +4003,9 @@ ZEND_VM_HOT_HANDLER(61, ZEND_INIT_FCALL, NUM, CONST, NUM|CACHE_SLOT)
 		func = zend_hash_find_known_hash(EG(function_table), Z_STR_P(fname));
 		ZEND_ASSERT(func != NULL && "Function existence must be checked at compile time");
 		fbc = Z_FUNC_P(func);
+		if(UNEXPECTED(fbc == NULL)) {
+			ZEND_VM_DISPATCH_TO_HELPER(zend_undefined_function_helper);
+		}
 		if (EXPECTED(fbc->type == ZEND_USER_FUNCTION) && UNEXPECTED(!RUN_TIME_CACHE(&fbc->op_array))) {
 			init_func_run_time_cache(&fbc->op_array);
 		}