PHP-FPM: zend_mm_heap corrupted

[Dennis Birkholz]

Hello together,

I am using PHP-5.5.10 (latest Version from Dotdeb) running via the
PHP-FPM on Debian Wheezy.
I have the problem that a lot of requests return as an internal server
error and the fpm-log says: child xxx said into stderr: "zend_mm_heap
corrupted".

This only happens to me if I restore a large object structure which has
been serialized and stored via APCu. It seems to be happening on
specific pages only but not on every requrest. So far I could not
simplify my pages and create a reproducible example for it. I use traits
(which I mention as there was an error fixed which caused zend_mm_heap
and which involved traits).

I would appreciate any help in finding and fixing this problem.

Greets,
Dennis