Codeigniter 2 “Only variable references should be returned by reference”

Only variable references should be Returned by reference codeigniter 2 php version 5.6, file common.php

Codeigniter 2 “Only variable references should be returned by reference”
How to fix error “Only variable references should be Returned by reference” CodeIgniter 2xxx, Filename: core / Common.php.
Line Number: 257
A PHP Error was encountered,Message: Only variable references should be returned by reference,Filename: core/Common.php,Line Number: 257. When using php version 5.6.3, CodeIgniter displays an error message like this

Codeigniter 2.xx Error “core/Common.php” PHP Version 5.6.3 [FIXED]

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