Online PHP editor | output for CgtGp

Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.28, 8.4.1 - 8.4.14, 8.5.0 - 8.5.1: Fatal error: Uncaught Error: Undefined constant "strtoupper" in /in/CgtGp:7 Stack trace: #0 {main} thrown in /in/CgtGp on line 7
Process exited with code 255.
Output for 8.4.15: /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.35' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.34' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15)
Process exited with code 1.
Output for 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33: Warning: Use of undefined constant strtoupper - assumed 'strtoupper' (this will throw an Error in a future version of PHP) in /in/CgtGp on line 7 Warning: strtoupper() expects exactly 1 parameter, 2 given in /in/CgtGp on line 7 Warning: strtoupper() expects exactly 1 parameter, 2 given in /in/CgtGp on line 7 Warning: strtoupper() expects exactly 1 parameter, 2 given in /in/CgtGp on line 7 Array ( [a] => apple [b] => banana [c] => cherry )
Output for 7.1.0 - 7.1.21: Notice: Use of undefined constant strtoupper - assumed 'strtoupper' in /in/CgtGp on line 7 Warning: strtoupper() expects exactly 1 parameter, 2 given in /in/CgtGp on line 7 Warning: strtoupper() expects exactly 1 parameter, 2 given in /in/CgtGp on line 7 Warning: strtoupper() expects exactly 1 parameter, 2 given in /in/CgtGp on line 7 Array ( [a] => apple [b] => banana [c] => cherry )