Description:
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forked from https://github.com/symfony/symfony/issues/38997

When PHP8RC3 is enabled in FPM mode, with preload enabled using Symfony 5.1.7 (or Symfony 5), when a page loads, and PHP accesses the Cache Pool randomly named folders, PHP Segfaults and crashes. 

Reproducible with a bare, new, Symfony demo app.

Test script:
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Install PHP 8.0.0 RC 3 (However you wish, mine was a docker container)
Install Symfony CLI binary

symfony new --demo my_project
edit .env set ENV=prod
php bin/console cache:clear

Edit php.ini and set (note your path & user might be different)

[opcache]
opcache.enable=1
opcache.preload='/application/var/cache/prod/App_KernelProdContainer.preload.php';
opcache.preload_user=www-data

cd my_project/public
php -S 0.0.0.0:8000
Try to load a webpage

Expected result:
----------------
No Segfault - page loads.

Actual result:
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see screenshot: https://user-images.githubusercontent.com/400092/98182889-c4f74d00-1efe-11eb-8d3e-930d67df7d88.png

"Segmentation Fault"

see screenshot: https://user-images.githubusercontent.com/400092/98183196-93cb4c80-1eff-11eb-8a00-4d03e02551be.png


When tracing the process I get to:

SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x10}