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<?php $a = 1; $c = $a + $a++; var_dump($c); // int(3)
Output for 5.1.1 - 7.4.2
int(3)
Output for 5.1.0
Fatal error: fatal flex scanner internal error--end of buffer missed in /in/9NPaY on line 5
Process exited with code 255.
Output for 4.3.0 - 5.0.5
int(2)