1--TEST-- 2Incorrect DCE of FREE of COALESCE 3--FILE-- 4<?php 5 6function test(?string $str) { 7 $str ?? $str = ''; 8 return strlen($str); 9} 10 11$foo = 'foo'; 12$foo .= 'bar'; 13var_dump(test($foo)); 14 15?> 16--EXPECT-- 17int(6) 18