[php-src] Issue #9775: Duplicates returned by array_unique when using enums

Issue: https://github.com/php/php-src/issues/9775 Author: jkobus ### Description The following code: ```php enum Test: string { case AUTHENTICATED = 'authenticated'; case COURSES_ADMIN = 'courses.admin'; case BUNDLES_ADMIN = 'bundles.admin'; case COURSES_REPORTING_ACCESS = 'courses-reporting.access'; case B2B_DASHBOARD_ACCESS = 'b2b-dashboard.access'; case INSTRUCTORS_ADMIN = 'instructors.admin'; case USERS_ADMIN = 'users.admin'; case COUPONS_ADMIN = 'coupons.admin'; } $data = [ Test::COURSES_ADMIN, Test::COURSES_REPORTING_ACCESS, Test::BUNDLES_ADMIN, Test::USERS_ADMIN, Test::B2B_DASHBOARD_ACCESS, Test::B2B_DASHBOARD_ACCESS, Test::INSTRUCTORS_ADMIN, Test::INSTRUCTORS_ADMIN, Test::COUPONS_ADMIN, Test::AUTHENTICATED, ]; $data = array_unique($data, flags: SORT_REGULAR); var_dump($data); <?php ``` Resulted in this output: ``` array(10) { [0]=> enum(Test::COURSES_ADMIN) [1]=> enum(Test::COURSES_REPORTING_ACCESS) [2]=> enum(Test::BUNDLES_ADMIN) [3]=> enum(Test::USERS_ADMIN) [4]=> enum(Test::B2B_DASHBOARD_ACCESS) [5]=> enum(Test::B2B_DASHBOARD_ACCESS) [6]=> enum(Test::INSTRUCTORS_ADMIN) [7]=> enum(Test::INSTRUCTORS_ADMIN) [8]=> enum(Test::COUPONS_ADMIN) [9]=> enum(Test::AUTHENTICATED) } ``` But I expected this output instead: ``` array(10) { [0]=> enum(Test::COURSES_ADMIN) [1]=> enum(Test::COURSES_REPORTING_ACCESS) [2]=> enum(Test::BUNDLES_ADMIN) [3]=> enum(Test::USERS_ADMIN) [4]=> enum(Test::B2B_DASHBOARD_ACCESS) [5]=> enum(Test::INSTRUCTORS_ADMIN) [6]=> enum(Test::COUPONS_ADMIN) [7]=> enum(Test::AUTHENTICATED) } ``` Quick preview: https://3v4l.org/f3XVY#v8.1.11 ### PHP Version PHP 8.1.11, 8.2rc3 ### Operating System _No response_