Description:
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Caller copy of "value" parameter is changed to string type by a call to set().

This bug is similar to Bug #9514 PHP Memcache::get modifies his second argument.

When caller program passes var with boolean, integer or float, the caller's copy of that var is changed to string type. Does not happen with array or object.

The caller's copy of the var should not be modified.

As with Bug #9514, preventing "by reference" passing stops problem: set($key, $value . '').

Reproduce code:
---------------
$m = new Memcache();
$m->addServer('localhost');

$value = 1.2;
echo gettype($value);

$m->set('asdf', $value);
echo '<br>';
echo gettype($value);

Expected result:
----------------
double
double

Actual result:
--------------
double
string