Runtime error with OPcache enabled: Numerical result out of range (34)

Hi all,

I cross-compiled PHP 5.6.0 to run on my Synology NAS and it works perfectly
fine right until I try to enable OPcache. After I enable it, running
php-cgi triggers an error similar to the following one:

Sun Sep 21 18:35:50 2014 (16384): Fatal Error Unable to allocate shared
memory segment of 67108864 bytes: unknown: Numerical result out of range
(34)

I tried googling this error up, but to no avail: I can't find any
indication of someone ever encountering a similar problem.

I attached phpinfo() page with OPcache disabled.

Any help with getting this solved is greatly appreciated!

-- 
Best regards,
Alex Potapenko