The Bugs Were Our Own Linker Wraps: Making a PHP Timeout Actually Time Out

Wed, 16 Sep 2026 19:35:00 -0700

In the stack guard post the villain was a -Wl,--wrap linker flag that turned off PHP’s C-stack overflow guard. It wasn’t the only one. Until August, max_execution_time did nothing in ePHPm on Linux, for the same reason. We had wrapped the function that arms it to a no-op. A runaway script ran until the HTTP layer’s request timeout gave up on it and sent a 504. The PHP thread kept burning CPU after that.

Config on Luther Monson

The Bugs Were Our Own Linker Wraps: Making a PHP Timeout Actually Time Out