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<?php class X { const abstract = A; function foo($a = A) {} } const A = new x();
Output for 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Fatal error: Uncaught Error: Undefined constant "A" in /in/cAQ9P:9 Stack trace: #0 {main} thrown in /in/cAQ9P on line 9
Process exited with code 255.

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