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run code in 300+ PHP versions simultaneously
<?php error_reporting(E_ALL); echo "string"; echo '123123'; session_start();
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
string123123 Warning: session_start(): Session cannot be started after headers have already been sent in /in/fj1NS on line 5
Output for 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33
string123123 Warning: session_start(): Cannot start session when headers already sent in /in/fj1NS on line 5
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.21, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20
string123123 Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /in/fj1NS:3) in /in/fj1NS on line 5 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/fj1NS:3) in /in/fj1NS on line 5
Output for 4.3.0 - 4.3.1
string123123 Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cookie - headers already sent by (output started at /in/fj1NS:3) in /in/fj1NS on line 5 Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cache limiter - headers already sent (output started at /in/fj1NS:3) in /in/fj1NS on line 5

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209.98 ms | 402 KiB | 314 Q