PHP 7 Compatibility

I ran the PHP Compatibility Checker plugin https://ww.wp.xz.cn/plugins/php-compatibility-checker/
checking for PHP 7 compatibility and got this result for this plugin:

FILE: wp-content/plugins/postie/lib/fEmail.php
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FOUND 0 ERRORS AND 4 WARNINGS AFFECTING 4 LINES
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  216 | WARNING | INI directive 'safe_mode' is deprecated since PHP 5.3 and removed since PHP 5.4.
  218 | WARNING | INI directive 'safe_mode_exec_dir' is deprecated since PHP 5.3 and removed since PHP 5.4.
  279 | WARNING | INI directive 'safe_mode' is deprecated since PHP 5.3 and removed since PHP 5.4.
 1435 | WARNING | INI directive 'safe_mode' is deprecated since PHP 5.3 and removed since PHP 5.4.
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