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      <base href="http://llvm.org/bugs/" />
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - Absurd program results in illegal hardware instruction under optimization"
   href="http://llvm.org/bugs/show_bug.cgi?id=16347">16347</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Absurd program results in illegal hardware instruction under optimization
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>clang
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>trunk
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Macintosh
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>MacOS X
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>C++11
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedclangbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>so.townsend@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>dgregor@apple.com, llvmbugs@cs.uiuc.edu
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=10691" name="attach_10691" title="Try removing the comment, it works then.">attachment 10691</a> <a href="attachment.cgi?id=10691&action=edit" title="Try removing the comment, it works then.">[details]</a></span>
Try removing the comment, it works then.

The attached program does not fail to compile but emits invalid instructions
when compiled under

clang++ -O4 -std=c++11
clang++ -O3 -std=c++11
clang++ -O2 -std=c++11

clang++ -O1 -std=c++11 results in a proper segmentation fault.

otool -Vt dump 
----------------------

Optimizer level 4:
(__TEXT,__text) section
_main:
0000000100000f70        ud2</pre>
        </div>
      </p>
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