See first answer for update.
I've got a strange problem with my page running on Phalcon 4.0.5.
I run PHP 7.4.5 as FPM served by Apache on Ubuntu 18.04. When I load the page, I get a "Service Temporarily Unavailable" error page. Pressing F5 causes the page to load as desired, another click on a internal link or a refresh causes the same error again. I had a look into the PHP error_log:
[Wed Aug 14 14:54:01.595030 2019] [proxy_fcgi:error] [pid 30506:tid 140331471267584] [client MYIP:46740] AH01067: Failed to read FastCGI header
[Wed Aug 14 14:54:01.595057 2019] [proxy_fcgi:error] [pid 30506:tid 140331471267584] (104)Connection reset by peer: [client MYIP:46740] AH01075: Error dispatching request to :
/var/log/syslog contains this:
Aug 14 14:54:01 localhost kernel: [529450.811751] traps: php-fpm general protection ip:55db5dd27350 sp:7ffcf3838f90 error:0 in php-fpm[55db5da78000+46f000]
Sometimes, it even triggers a segfault:
Aug 14 15:28:27 localhost kernel: [531517.048371] php-fpm: segfault at 1a ip 000055db5dd3e1fe sp 00007ffcf3838d20 error 4 in php-fpm[55db5da78000+46f000]
All other pages on the server (which run without Phalcon) do work normally.
Is this related to Phalcon itself, or something's up with my PHP installation?