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<?php $x = str_repeat('foo', 500000000); $y = 'bar'; $before = microtime(1); $x = $x . $y; var_dump(microtime(1) - $before);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.7, 7.2.0
Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 1500000032 bytes) in /in/Heo17 on line 3
Process exited with code 255.
Output for 5.2.1 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28
Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 1500000001 bytes) in /in/Heo17 on line 3
Process exited with code 255.
Output for 5.2.0
Fatal error: Out of memory (allocated 262144) (tried to allocate 1500000001 bytes) in /in/Heo17 on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6

Process exited with code 137.
preferences:
151.75 ms | 402 KiB | 216 Q