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      <base href="https://llvm.org/bugs/" />
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - clang fails to use constexpr variable template as default value of non-type template argument"
   href="https://llvm.org/bugs/show_bug.cgi?id=24903">24903</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>clang fails to use constexpr variable template as default value of non-type template argument
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>3.7
          </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>C++14
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>fmatthew5876@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>template <typename T>
constexpr int A = 1;

template <typename T, int a = A<T>>
  struct B {};

template struct B<int>;

The above code compiles in gcc but fails to compile in clang 3.7 with the
following error:
error : non-type template argument is not a constant expression

Theres also a stack overflow question with this same issue where someone claims
the bug was fixed when in fact it appears that it was not.

<a href="http://stackoverflow.com/questions/30260489/is-it-possible-to-use-a-constexpr-template-variable-as-the-default-for-a-forma/32702600#32702600">http://stackoverflow.com/questions/30260489/is-it-possible-to-use-a-constexpr-template-variable-as-the-default-for-a-forma/32702600#32702600</a></pre>
        </div>
      </p>
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