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<base href="https://bugs.webkit.org/" />
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Function Incorrectly Cached"
href="https://bugs.webkit.org/show_bug.cgi?id=151354">151354</a>
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<th>Summary</th>
<td>Function Incorrectly Cached
</td>
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<th>Classification</th>
<td>Unclassified
</td>
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<th>Product</th>
<td>WebKit
</td>
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<th>Version</th>
<td>Safari 9
</td>
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<th>Hardware</th>
<td>Macintosh
</td>
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<th>OS</th>
<td>Mac OS X 10.11
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
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<tr>
<th>Severity</th>
<td>Critical
</td>
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<th>Priority</th>
<td>P2
</td>
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<th>Component</th>
<td>JavaScriptCore
</td>
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<th>Assignee</th>
<td>webkit-unassigned@lists.webkit.org
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</tr>
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<th>Reporter</th>
<td>bnkuhn@gmail.com
</td>
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<p>
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<pre>Calling the following function many times can confuse Safari into caching the result (probably actually caching the compiled/optimized code for the function).
function getOne(a) { return a['1']; }
This specific function is not the problem; it just represents the simplest case. See the following live example:
<a href="http://jsfiddle.net/60ygm4uk/15/">http://jsfiddle.net/60ygm4uk/15/</a>
Steps to Reproduce:
1) Call getOne({2: true}); many times (at least 36 times).
2) Call getOne({1: true});
Expected Results:
getOne({1: true}) should return true.
Actual Results:
getOne({1: true}) returns undefined.
Severity:
Causes bugs in major JavaScript libraries (i.e. Google Analytics). Millions of sites potentially affected.</pre>
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