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<?php class Foo { protected $titleInfo = []; /** @return array */ public function bar() { $key = ''; if ( !isset( $this->titleInfo[$key] ) ) { $this->titleInfo[$key] = [ 42 ]; } return $this->titleInfo[$key]; # The critical line } } $value = ( new Foo )->bar(); var_dump( $value );
Output for 7.1.25 - 7.1.30, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.29, 8.2.0 - 8.2.21, 8.3.0 - 8.3.9
array(1) { [0]=> int(42) }

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