<html>
    <head>
      <base href="https://bugs.llvm.org/">
    </head>
    <body><span class="vcard"><a class="email" href="mailto:richard-llvm@metafoo.co.uk" title="Richard Smith <richard-llvm@metafoo.co.uk>"> <span class="fn">Richard Smith</span></a>
</span> changed
          <a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED INVALID - a pass error, this pass never consider data overflow"
   href="https://bugs.llvm.org/show_bug.cgi?id=40496">bug 40496</a>
          <br>
             <table border="1" cellspacing="0" cellpadding="8">
          <tr>
            <th>What</th>
            <th>Removed</th>
            <th>Added</th>
          </tr>

         <tr>
           <td style="text-align:right;">Resolution</td>
           <td>---
           </td>
           <td>INVALID
           </td>
         </tr>

         <tr>
           <td style="text-align:right;">Status</td>
           <td>NEW
           </td>
           <td>RESOLVED
           </td>
         </tr></table>
      <p>
        <div>
            <b><a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED INVALID - a pass error, this pass never consider data overflow"
   href="https://bugs.llvm.org/show_bug.cgi?id=40496#c1">Comment # 1</a>
              on <a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED INVALID - a pass error, this pass never consider data overflow"
   href="https://bugs.llvm.org/show_bug.cgi?id=40496">bug 40496</a>
              from <span class="vcard"><a class="email" href="mailto:richard-llvm@metafoo.co.uk" title="Richard Smith <richard-llvm@metafoo.co.uk>"> <span class="fn">Richard Smith</span></a>
</span></b>
        <pre>This example has undefined behaviour due to signed overflow. In a correct
program, it is not possible for adding an unsigned char to a positive integer
to produce a negative integer, so the optimisation is correct.

If you want to write nonstandard code that assumes that signed overflow wraps
around, you can use -fwrapv to define this otherwise-undefined behaviour as
wrapping.</pre>
        </div>
      </p>


      <hr>
      <span>You are receiving this mail because:</span>

      <ul>
          <li>You are on the CC list for the bug.</li>
      </ul>
    </body>
</html>