Fixing “Maximum Function Nesting Level Reached” in Evolution CMS Cache Sync

If Evolution CMS starts throwing Maximum function nesting level reached inside the cache sync processor, the parser itself is not always the real problem. In many local environments, this is a sign that Xdebug’s nesting protection is being triggered during a cache rebuild or a recursive execution path.

The symptom usually appears after an update or a change in the local stack:

Fatal error: Maximum function nesting level of '1000' reached, aborting!
in .../manager/processors/cache_sync.class.processor.php

That often means one of two things:

• a local debugging extension is limiting call depth during a heavy cache sync path;
• or a real recursion bug was introduced and only became visible under the updated environment.

The first step is to reproduce the issue with Xdebug disabled or its nesting limits adjusted. If the problem disappears, the stack is warning you about depth, not necessarily corruption. If it remains, then you are likely dealing with a plugin, parser, or sync path that has turned recursive.

For Evolution maintainers, this is a useful reminder that cache sync errors after an update are sometimes environment-specific, especially on local Windows or bundled stacks.