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      <base href="https://bugs.llvm.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Miscompilation in middle-end (pointer arithmetic and comparisons)"
   href="https://bugs.llvm.org/show_bug.cgi?id=49662">49662</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Miscompilation in middle-end (pointer arithmetic and comparisons)
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>libraries
          </td>
        </tr>

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

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux
          </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>Scalar Optimizations
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>maltsevm@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=24663" name="attach_24663" title="Reproducer as C source code">attachment 24663</a> <a href="attachment.cgi?id=24663&action=edit" title="Reproducer as C source code">[details]</a></span>
Reproducer as C source code

The attached source code is miscompiled with trunk build of Clang:

$ clang -O2 test.c -o test && ./test
failed: distance(i, j) >= 2

(the expected output is "passed")

Git bisect points to the following commit:
<a href="https://github.com/llvm/llvm-project/commit/2ad1f5eb1a47275593bd9baf75dcf3e9c3977473">https://github.com/llvm/llvm-project/commit/2ad1f5eb1a47275593bd9baf75dcf3e9c3977473</a>
(although it might not be the root cause)

I tried to reduce the test case in such a way that LLVM IR still looked
reasonable to me and got the following result:

$ lli test-reduced.ll
passed
$ opt -indvars -inline -instcombine -jump-threading test-reduced.ll -o test.bc
$ lli test.bc
failed: distance(i, j) >= 2</pre>
        </div>
      </p>


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