<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/118246>118246</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Clang]Uninitialized variables are set to -1 at optimization levels of - O1 and above
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          muxiff
      </td>
    </tr>
</table>

<pre>
    Consider the following case ，
https://godbolt.org/z/8fKaq9Yhh

 When the optimization level is - O1 or above, it is found that uninitialized variables are set to -1 by default, which is different from the behavior of gcc's policy setting to 0 by default. Is this the default policy of LLVM with optimization, is there a way to avoid it, or is it necessary to strictly manually set the initial value of all variables？


</pre>
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