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To: <internals@lists.php.net>, "Dmitry Stogov" <dmitry@php.net>,
        "Michael Wallner" <mike@php.net>
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Date: Tue, 7 Nov 2006 05:25:50 -0600
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Subject: Re: [PHP-DEV] Re: [PATCH] =& doesn't remove "old" references like unset()
From: php_lists@realplain.com ("Matt Wilmas")

----- Original Message -----
From: "Michael Wallner"
Sent: Tuesday, November 07, 2006

> Matt Wilmas wrote:
> > Hi (Dmitry?),
> >
> > See Bug #33282 -- I saw it in the Bug Summary; don't know if there are
other
> > related ones...  Same applies to foreach ($arr ... &$v) which is where I
> > noticed it last week with var_dump($arr).  All elements that WERE
referenced
> > but aren't anymore still have is_ref=1 (when refcount=1).  Only the last
> > referenced element should be a reference (unless the others were to
begin
> > with).  unset()'ing the reference variable removes the reference from
the
> > last element.  Example:
> >
> > $a = array(1, 2, 3);
> > $r = &$a[0];
> > $r = &$a[1];
> > $r = &$a[2];
> > var_dump($a);
> >
> > array(3) {
> >   [0]=>
> >   &int(1)
> >   [1]=>
> >   &int(2)
> >   [2]=>
> >   &int(3)  // unset($r) will take care of this one
> > }
> >
> > The reference (&) should no longer be on the first 2 elements, right?
> > Setting is_ref=0 when refcount=1 in zend_assign_to_variable_reference()
> > fixes it.  I assume it won't cause other problems since the same thing
is
> > done in zval_ptr_dtor(). :-)
> >
>
> This looks like it may actually fix a lot of previously bogus'ed bug
reports?

Not sure which ones you mean (searching for "reference" returns many bugs,
and I didn't look very thoroughly), but so everyone knows since I mentioned
foreach(), this doesn't change the behavior reported in Bugs #36240, #37410,
#39307, etc...

> --
> Michael

Matt