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To: PHP Development <internals@lists.php.net>
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Subject: Memory usage and refcount
From: patrickallaert@php.net (Patrick ALLAERT)

Hi,

While debugging some memory usage stuff I came across the fact that:

<?php
class foo {
    // $x as a static *class* var
    static $x = "foo";
    static function def() {
        return self::$x;
    }
}

$x1 = foo::def();
$x2 = foo::def();
$x3 = foo::def();
$x4 = foo::def();

xdebug_debug_zval('x4');
?>

will display a refcount of 5 while:

<?php
class foo {
    static function def() {
        // $x as a static *function* var
        static $x = "foo";
        return $x;
    }
}

$x1 = foo::def();
$x2 = foo::def();
$x3 = foo::def();
$x4 = foo::def();

xdebug_debug_zval('x4');
?>

will display a refcount of 1.

Can someone explain me why a real copy is made in the 2nd case?
Is this on purpose?

Regards,
-- 
Patrick Allaert
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