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    <head>
      <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 - Address of dllimport symbol is not constexpr"
   href="https://bugs.llvm.org/show_bug.cgi?id=51558">51558</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Address of dllimport symbol is not constexpr
          </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>Windows NT
          </td>
        </tr>

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

        <tr>
          <th>Severity</th>
          <td>enhancement
          </td>
        </tr>

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

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

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

        <tr>
          <th>Reporter</th>
          <td>skyostil@chromium.org
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>blitzrakete@gmail.com, dgregor@apple.com, erik.pilkington@gmail.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
          </td>
        </tr></table>
      <p>
        <div>
        <pre>The following C++ program fails to compile on the x64_64-pc-windows-msvc
target:

  extern __declspec(dllimport) int x;
  constexpr int* y = &x;

Error message:

  test.cc(7,16): error: constexpr variable 'y' must be initialized by a
constant expression

This is on Clang version 14.0.0 (<a href="https://github.com/llvm/llvm-project/">https://github.com/llvm/llvm-project/</a>
ee65938357d5fffe9e586fa155b37268b5a358ac), target: x86_64-pc-windows-msvc. I
ran into this while trying to compile Perfetto (<a href="https://perfetto.dev">https://perfetto.dev</a>) as a part
of Chromium.

The same program builds correctly on MSVC (tested on 19.29.30037 for x64).
Interestingly, MSVC had a regression related to this in 2018[1] which has since
been fixed.

[1]
<a href="https://developercommunity.visualstudio.com/t/c-regression-stdmax-of-two-constexpr-does-not-eval/312456">https://developercommunity.visualstudio.com/t/c-regression-stdmax-of-two-constexpr-does-not-eval/312456</a></pre>
        </div>
      </p>


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