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<?php function userland_func_get_arg($idx) { return isset(debug_backtrace()[1]['args'][$idx]) ? debug_backtrace()[1]['args'][$idx] : false; } function foo(&$arg) { $a = &func_get_arg(0); $a = 'bar'; } function bar(&$arg) { $a = &userland_func_get_arg(0); $a = 'bar'; } $foo = 'foo'; var_dump(foo($foo, 'bar')); var_dump($foo); $foo = 'foo'; var_dump(bar($foo, 'bar')); var_dump($foo);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Notice: Only variables should be assigned by reference in /in/utd0V on line 5 NULL string(3) "foo" Notice: Only variables should be assigned by reference in /in/utd0V on line 6 NULL string(3) "foo"
Output for 7.3.32 - 7.3.33
NULL string(3) "foo" NULL string(3) "foo"
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
Strict Standards: Only variables should be assigned by reference in /in/utd0V on line 5 NULL string(3) "foo" Strict Standards: Only variables should be assigned by reference in /in/utd0V on line 6 NULL string(3) "foo"
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Fatal error: Can't use function return value in write context in /in/utd0V on line 3
Process exited with code 255.
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected T_STRING, expecting T_VARIABLE or '$' in /in/utd0V on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected T_STRING, expecting T_VARIABLE or '$' in /in/utd0V on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/utd0V on line 3
Process exited with code 255.
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