php 8.4: Implicitly marking parameter $params as nullable is deprecated, the explicit nullable type must be used instead

Author: tenzapCreated Sep 29, 2024Updated May 9, 2026

When running the tests of ci3 with php8.4, I get these deprecation warnings:

PHP Deprecated:  CI_Encryption::encrypt(): Implicitly marking parameter $params as nullable is deprecated, the explicit nullable type must be used instead in .../system/libraries/Encryption.php on line 372
PHP Deprecated:  CI_Encryption::decrypt(): Implicitly marking parameter $params as nullable is deprecated, the explicit nullable type must be used instead in .../system/libraries/Encryption.php on line 507
.
Deprecated: CI_Encryption::encrypt(): Implicitly marking parameter $params as nullable is deprecated, the explicit nullable type must be used instead in .../system/libraries/Encryption.php on line 372

Deprecated: CI_Encryption::decrypt(): Implicitly marking parameter $params as nullable is deprecated, the explicit nullable type must be used instead in .../system/libraries/Encryption.php on line 507