<html>
    <head>
      <base href="http://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 --- - Missing symbol at link time for constexpr class const static member if they are arrays."
   href="http://llvm.org/bugs/show_bug.cgi?id=18696">18696</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Missing symbol at link time for constexpr class const static member if they are arrays.
          </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>All
          </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>-New Bugs
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>galopin@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvmbugs@cs.uiuc.edu
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>The following sample do not link, s_ is missing at link time. 

=================================
#include <iostream>

struct Foo {
    constexpr int operator()(int v) const { return v+s_[0]; }
    void notok( std::ostream & os ) const {
        os << s_[0] << std::endl;
    }
    static constexpr int const s_[]{ 3 };
};

int main() {
    constexpr Foo const bar{};

    constexpr auto const ok = bar(10);
    std::cout << ok << std::endl;
    bar.notok( std::cout );
}
=================================

If s_ is not an array type, the sample link correctly

=================================
#include <iostream>

struct Foo {
    constexpr int operator()(int a) const { return a+s_; }
    void notok( std::ostream & os ) const {
        os << s_ << std::endl;
    }
    static constexpr int const s_{ 3 };
};

int main() {
    constexpr Foo const bar{};

    constexpr auto const ok = bar(10);
    std::cout << ok << std::endl;
    bar.notok( std::cout );
}
=================================</pre>
        </div>
      </p>
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      <ul>
          <li>You are on the CC list for the bug.</li>
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