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<td class="text-paragraph-pattern-container mobile-resize-text " style="padding: 0px; border-collapse: collapse; padding: 0 0 10px 0"> <p style="margin: 10px 0 0 0; margin-top: 0"><cite style="font-style: italic"> (I also don't think those warnings are fixable either.)</cite></p> <p style="margin: 10px 0 0 0">You may be right, or I may be missing something.</p> <p style="margin: 10px 0 0 0">I started looking at this and got rapidly lost. I suspect that this is too much exposure to Microsoft's SAL (a psuedo-semantically aware static code analyzer).</p> <p style="margin: 10px 0 0 0">The bug seems obvious. Given</p>
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<pre class="code-java" style="margin: 10px 0 0 0; margin-top: 0; max-height: 30em; overflow: auto; white-space: pre-wrap; word-wrap: normal">
<span class="code-object" style="color: #910091">int</span> cursor
<span class="code-keyword" style="color: #000091">if</span> ((cursor + 2) > upper) \{
SomeArray[cursor] = somevalue;
}
</pre>
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</div> <p style="margin: 10px 0 0 0">if cursor is <tt>maxint - 1</tt> then badness ensues. From the structure of the code for cursor to be bigger than 200 would be a different bug and to be as big as <tt>maxint - 1</tt> would be one which would have caused chaos already. Nonetheless this is a bug, so lets protect against it.</p> <p style="margin: 10px 0 0 0">So why not say</p>
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<span class="code-keyword" style="color: #000091">if</span> (cursor > (std::numeric_limits<<span class="code-object" style="color: #910091">int</span>>::max() - 2) &&
(cursor + 2) > upper) \{
SomeArray[cursor] = somevalue;
}
</pre>
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</div> <p style="margin: 10px 0 0 0">But as I recall I now have two warnings. One because I am subtracting 2 from <tt>std::numeric_limits<int>::max()</tt> and one because I am adding 2 to cursor.</p> <p style="margin: 10px 0 0 0">So the compiler doesn't know abdout std::numeric_limits, or I am misunderstanding the issue and there is another one, or I am being overoptimistic about the smartness of the compiler (SAL isn't very smart but it does understand this sort of thing).</p> <p style="margin: 10px 0 0 0"> </p> </td>
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