Description:
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When making a reference on a string offset and changing it, PHP5.3 crashes with segfault, but PHP 5.2, 5.1 and 5.0 throws errors.

I know that it's a bad PHP programming than thinking PHP is C, the fact is that this behavior gives PHP errors in 5.2/5.1/5.0 branches, but segfaults 5.3.0 release.

Reproduce code:
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<?php
$a = "string";
$b = &$a[1];
$b = "f";
echo $a;

Expected result:
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sfring

But PHP5.2.0 and 5.0.0 tell :
"Fatal error: Cannot create references to/from string offsets nor overloaded objects in XXX"

PHP 5.1.0 tells:
"Fatal error: fatal flex scanner internal error--end of buffer missed in XXX"

PHP5.3 segfaults


Actual result:
--------------
segmentation faults