<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=http://email.email.llvm.org/c/eJylks1u2zAMx5_GvhA1_KXYPviQJWux-15AsmhbnSJlFpU0ffrRDoqtxQYUGEDJokj_-ZNE5fWt3zuILgbUkOzyQDqp9myB5PCDN8CrZxwIroZmoBlB4yijpXfJGn9GXJMV_4ROgwngPIFC4yZAa07GSUKdwfeZQ2zSBg-0RITRL_B0OMADBESYic5hFS0f2SavlbeU-WVi75VHU3dfn16eX4osyY9Jvr_P30a4-QjDLN2EG-UbCPl3oBc-il9WUrMeyVpGhMGfzhYJ7e0PVDAODlau-Bd0YO4VzjHMHNOSJCewuKFso9-0vGOJv6mt1ViBZ-0xuKRsiPMcSS4i3e2u97kLGIMcJIr2NUt1X-mu6mQqI81-6Uez4FVeMI2L7T_o8OtFlTEbO9Ze3j4P58Wvz8uuCSFi4IWoyl2bzr3shGjrvNgVQz4Uos5FUzWiU-MOi1ZpkVqp0IY-EV-SsnR4hU2C14k4pv9PYPoyL8u8KNpCFHndZl3T6VqMom60GsemSuocT9LYbNVZryhd-k1SxSlw0JpA4XdQhmAmh7gBMyEZstgfUWr40PXl4_vO_lc7pxtxv-H-AjtZE9M>53268</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Dead std::stack/std::deque is not being eliminated
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    An unused `std::stack` object with the default `std::deque` backend is not being eliminated. This is also true for GCC - see https://godbolt.org/z/749EGxjx1.

If you change the backend to `std::vector` it will be completely eliminated in Clang even if you pushed data into it. GCC will only completely eliminate it if it doesn't contain any data - see https://godbolt.org/z/fsacae58z.
</pre>
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