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<?php session_start(); class test { function test() { $bar = &$_SESSION['foo']; } } var_dump($_SESSION['foo']); $test=new test(); $foo = 1; ?>
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
Warning: Undefined array key "foo" in /in/LN0V1 on line 12 NULL
Output for 7.4.0 - 7.4.25, 7.4.27 - 7.4.33
Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; test has a deprecated constructor in /in/LN0V1 on line 4 Warning: session_start(): Cannot start session when headers already sent in /in/LN0V1 on line 2 Notice: Undefined variable: _SESSION in /in/LN0V1 on line 12 Notice: Trying to access array offset on value of type null in /in/LN0V1 on line 12 NULL
Output for 7.3.32 - 7.3.33, 7.4.26
NULL
Output for 7.2.0 - 7.2.33, 7.3.12 - 7.3.31
Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; test has a deprecated constructor in /in/LN0V1 on line 4 Warning: session_start(): Cannot start session when headers already sent in /in/LN0V1 on line 2 Notice: Undefined variable: _SESSION in /in/LN0V1 on line 12 NULL
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20
Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; test has a deprecated constructor in /in/LN0V1 on line 4 Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /in/LN0V1:4) in /in/LN0V1 on line 2 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/LN0V1:4) in /in/LN0V1 on line 2 Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.36, 5.6.0 - 5.6.28
Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL
Output for 5.3.0 - 5.3.29
Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL Warning: Unknown: Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively in Unknown on line 0
Output for 5.2.10 - 5.2.17
Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL Warning: Unknown: Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively in Unknown on line 0
Output for 5.2.3 - 5.2.9
Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL Warning: Unknown: Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively. in Unknown on line 0
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.2
Warning: session_start(): Cannot send session cookie - headers already sent in /in/LN0V1 on line 2 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/LN0V1:2) in /in/LN0V1 on line 2 Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL Warning: Unknown: Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively. in Unknown on line 0
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9
Warning: session_start(): Cannot send session cookie - headers already sent in /in/LN0V1 on line 2 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/LN0V1:2) in /in/LN0V1 on line 2 Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL Warning: Unknown(): Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively. in Unknown on line 0
Output for 4.3.0 - 4.3.1
Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cookie - headers already sent in /in/LN0V1 on line 2 Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cache limiter - headers already sent (output started at /in/LN0V1:2) in /in/LN0V1 on line 2 Notice: Undefined index: foo in /in/LN0V1 on line 12 NULL Warning: Unknown(): Your script possibly relies on a session side-effect which existed until PHP 4.2.3. Please be advised that the session extension does not consider global variables as a source of data, unless register_globals is enabled. You can disable this functionality and this warning by setting session.bug_compat_42 or session.bug_compat_warn to off, respectively. in Unknown on line 0

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