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<?php class a { private $b; function __construct($b = NULL) { if ($b) $this->b = $b; else $this->b = new b($this); $this->b->test(); } public function test() { echo ($this->b !== NULL) ? __METHOD__.":: b not NULL\n" : __METHOD__." :: b NULL\n"; } } class b { function __construct($a) { $a->test(); } } new a;
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 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
a::test :: b NULL Fatal error: Uncaught Error: Call to undefined method b::test() in /in/RU4W8:10 Stack trace: #0 /in/RU4W8(26): a->__construct() #1 {main} thrown in /in/RU4W8 on line 10
Process exited with code 255.
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, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
a::test :: b NULL Fatal error: Call to undefined method b::test() in /in/RU4W8 on line 10
Process exited with code 255.
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/RU4W8 on line 4
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_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/RU4W8 on line 4
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_OLD_FUNCTION' or `T_FUNCTION' or `T_VAR' or `'}'' in /in/RU4W8 on line 4
Process exited with code 255.

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