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<?php class A { public function query(): array { return []; } } class B extends A { public function query(): int { return 0; } } $o = new B; var_dump($o->query());
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.7
Fatal error: Declaration of B::query(): int must be compatible with A::query(): array in /in/EoXf6 on line 13
Process exited with code 255.

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