Description:
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Repeated calls to str_ireplace appear to cause memory corruption if replacement is made. In my web application, the resulting string will "echo" fine but html page generated in subsequent class module is never served.  str_replace works fine.  Code working fine until upgrade to 5.2.1.

Thanks - great stuff you guys do!

Reproduce code:
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$str_s = str_replace( array('(t)', '(tm)',   '™', chr(153)),	' (trade marked)',	$str_s );

$str_s = str_replace( array('(r)', '(reg)',  '®',   chr(174)),	' (registered)',	$str_s );

$str_s = str_replace( array('(c)', '(copy)', '©',  chr(169)),	' (copyrighted)',	$str_s );


Expected result:
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proper substitution and web page served

Actual result:
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guessing memory corruption as html never generated.