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    <head>
      <base href="https://llvm.org/bugs/" />
    </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 --- - reinterpret_cast throws off static analyzer"
   href="https://llvm.org/bugs/show_bug.cgi?id=28344">28344</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>reinterpret_cast throws off static analyzer
          </td>
        </tr>

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

        <tr>
          <th>Assignee</th>
          <td>kremenek@apple.com
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>eric.huhtala@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>assignment via reinterpret_cast seems to throw off all analysis of that
variable.  

Example Code:

extern unsigned *b;
unsigned f() {

    // if I reassign b via reinterpret_cast, I get "Undefined or garbage value
returned to caller" at g(dummy)
    // if I don't, I get no warning
    unsigned *b = reinterpret_cast<unsigned*>(4);
    unsigned char a = (*b == 0) ? *b : 0;

    unsigned dummy;
    if (a == 0) dummy = 0;
    return dummy;
}</pre>
        </div>
      </p>
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