I got error message
=================
Error: E_ERROR
Call to undefined function x2()
at /a/b/c/d/YY.php line 25
==========================
However, the function X1() in the same include file was executed before this error message.
Previously, I had the same problem with X1(), but somehow the error message went away and the system started to run under debug mode.

We recently upgraded to NuSphere 5.2.

I never had the problem like this in NuSphere 4.5.

This is an error produced by php itself and sounds like you have a missed include() or a unresolved include(). PhpED is not involved in the process of running php and may not make your functions defined or undefined. Please check your code logic.

I found the cause.

When I was creating the code, I opened the specification document.

The document contains the control characters that were copied into the PHP editor.

I checked the code with Hex Editor and confirmed the problem.

I will be careful in the future about the control characters.