PHP 7 Comptability problems

Hi guys,

So, I’m looking to update my sites to PHP 7 soon. And I decided to do compatibility tests with the PHP Compatibility Test plugin. I got the following warnings and errors:

In the file plugins/wp-user-manager/vendor/alessandrotesoro/wp-optionskit/wp-optionskit.php
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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400 | WARNING | Global with anything other than bare variables is discouraged since PHP 7.0. Found ${$this->func . ‘_options’}
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In the file plugins/wp-user-manager/includes/wpum-upgrades/class-wpum-updates.php
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FOUND 0 ERRORS AND 12 WARNINGS AFFECTING 12 LINES
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165 | WARNING | Method name “WPUM_Updates::__register_plugin_addon_updates” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
184 | WARNING | Method name “WPUM_Updates::__register_upgrade” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
200 | WARNING | Method name “WPUM_Updates::__change_users_label” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
233 | WARNING | Method name “WPUM_Updates::__register_menu” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
273 | WARNING | Method name “WPUM_Updates::__redirect_admin” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
296 | WARNING | Method name “WPUM_Updates::__pause_db_update” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
352 | WARNING | Method name “WPUM_Updates::__restart_db_update” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
387 | WARNING | Method name “WPUM_Updates::__health_background_update” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
546 | WARNING | Method name “WPUM_Updates::__show_notice” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
678 | WARNING | Method name “WPUM_Updates::__flush_resume_updates” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
697 | WARNING | Method name “WPUM_Updates::__wpum_start_updating” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
724 | WARNING | Method name “WPUM_Updates::__wpum_db_updates_info” is discouraged; PHP has reserved all method names with a double underscore prefix for future use.
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And in the file plugins/wp-user-manager/includes/wpum-admin/class-wpum-background-updater.php
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FOUND 1 ERROR AFFECTING 1 LINE
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210 | ERROR | Indirect access to variables, properties and methods will be evaluated strictly in left-to-right order since PHP 7.0. Use curly braces to remove ambiguity.
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