Error when updating active plugins

[denisflorin197]

Hello,

We are having a custom integration with WordPress core.

Everything was fine until version 5.9.3. Since WP 6.0+ every update on plugins returns this error:

[11-Sep-2022 20:14:18 UTC] PHP Recoverable Error:  Uncaught exception 'Error' with message 'Call to undefined function wp_cache_get()' in /app/web/wp-includes/option.php on line 281, request: GET /wp-admin/index.php, request_id: b9bf26f9aee035e6b65287771ba589e3
[11-Sep-2022 20:14:18 UTC] PHP Recoverable Error:  Uncaught exception 'Error' with message 'Call to undefined function wp_cache_get()' in /app/web/wp-includes/option.php on line 281, request: GET /wp-admin/index.php, request_id: 5fc1f196f122f6eca601973062d7d013

Sometimes, this error is also present:

[02-Sep-2022 07:35:44 UTC] PHP Fatal error:  Cannot redeclare get_locale() (previously declared in /app/web/wp-includes/l10n.php:31) in /app/web/wp-includes/l10n.php on line 30
[02-Sep-2022 07:35:44 UTC] PHP Compile Error:  Cannot redeclare get_locale() (previously declared in /app/web/wp-includes/l10n.php:31) in /app/web/wp-includes/l10n.php on line 30, request: GET /26697/repurpose/20-brilliant-ways-repurpose-school-supplies-summer/2, request_id: 5aad3ad6ef7baef5602a318153220967

Do you have any ideas about what could cause this or what change could affect this?

Thank you

[denisflorin197]

It was a problem with WP PHP preloading

[SergeyBiryukov]

Hi there, welcome to WordPress Trac! Thanks for the follow-up.

Glad you were able to identify and resolve the issue.