Description:
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This problem showed up after an upgrade to php 5.2.3 that was accompanied by a pcre upgrade to ver 7.0.  It works fine on my local system (php 5.2.3, pcre 6.7)

The browser returns a download dialog rather than an error.

If I remove the "=" from the pattern, it works, but doesn't find anything.


Reproduce code:
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<?php
$s = "((?is-U)<input(?:(?:\s*\w*\s*(?:=(?:(?:'.*?')|(?:\".*?\")|(?:\w*)))?)*)(?:>|(?:\/>)))";
$formHTML = "Nothing to see here:<input name='blah' value=''></input>";
echo preg_replace("/" . $s . "/is", "muffin", $formHTML);

?>

Expected result:
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I would expect this code to replace the input tag string with "muffin".  I would also expect it not to crash.

Actual result:
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Download dialog box.