<div dir="ltr">Have added these assertions in r272515.</div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Jun 2, 2016 at 10:42 PM, Dylan McKay <span dir="ltr"><<a href="mailto:dylanmckay34@gmail.com" target="_blank">dylanmckay34@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><p style="margin:0px 0px 1.2em!important">I will be writing the code that calls this. The method bodies are extracted verbatim from <code style="font-size:0.85em;font-family:Consolas,Inconsolata,Courier,monospace;margin:0px 0.15em;padding:0px 0.3em;white-space:pre-wrap;border:1px solid rgb(234,234,234);border-radius:3px;display:inline;background-color:rgb(248,248,248)">isIntN</code>, which is used exclusively in in-tree MC/backend code. This would’ve silently overflowed in any of the 34 occurrences of this function in-tree.</p><span class="">
<blockquote style="margin:1.2em 0px;border-left-width:4px;border-left-style:solid;border-left-color:rgb(221,221,221);padding:0px 1em;color:rgb(119,119,119);quotes:none">
<p style="margin:0px 0px 1.2em!important">Probably best to return the correct result for N==64 and then (if appropriate) error out for N<1 and N>64</p>
</blockquote>
</span><p style="margin:0px 0px 1.2em!important">I agree, I’ll add this in. Let’s hope it doesn’t bring out any latent bugs.</p>
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<br>
Probably best to return the correct result for N==64 and then (if appropriate) error out for N<1 and N>64.<span><font color="#888888"><br>
<br>
John</font></span><span><br>
<br>
<br>
On 6/2/16 12:32 PM, Dylan McKay wrote:<br>
</span><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span>
How do you think this should be handled? Assertion error?<br>
<br>
On Thu, Jun 2, 2016 at 10:10 PM, John Regehr <<a href="mailto:regehr@cs.utah.edu" target="_blank">regehr@cs.utah.edu</a><br></span><span>
<mailto:<a href="mailto:regehr@cs.utah.edu" target="_blank">regehr@cs.utah.edu</a>>> wrote:<br>
<br>
/// Gets the maximum value for a N-bit unsigned integer.<br>
-inline uint64_t maxUIntN(uint64_t N) { return UINT64_C(1) << N; }<br>
+inline uint64_t maxUIntN(uint64_t N) { return (UINT64_C(1) <<<br>
N) - 1; }<br>
<br>
<br>
This is still wrong unless N is guaranteed to be no greater than 63.<br>
<br>
John<br>
<br>
<br>
</span></blockquote>
</blockquote></div><br></div>
</div></div></blockquote></div><br></div>