<html>
    <head>
      <base href="https://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 --- - Incomplete initializer when using metafunction in trailing return type"
   href="https://llvm.org/bugs/show_bug.cgi?id=27918">27918</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Incomplete initializer when using metafunction in trailing return type
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>3.8
          </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>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>barry.revzin@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>Consider this code (simplified from
<a href="http://stackoverflow.com/q/37493026/2069064">http://stackoverflow.com/q/37493026/2069064</a>, see also
<a href="http://coliru.stacked-crooked.com/a/0d9e9c1dacac6961">http://coliru.stacked-crooked.com/a/0d9e9c1dacac6961</a>):

#include <utility>

template <typename Function, typename... Args>
auto Call(Function func, Args... args) 
#if TRAILING == 1
    -> std::result_of_t<Function&(Args...)>
#elif TRAILING == 2
    -> typename std::result_of<Function&(Args...)>::type
#endif
{
    return func(args...);
}

int main()
{
    auto call = Call<int(int), int>;
    (void)call;
}

When compiling with -DTRAILING=0 or -DTRAILING=1, the code compiles fine. When
compiling with -DTRAILING=2, clang emits:

main.cpp:16:10: error: variable 'call' with type 'auto' has incompatible
initializer of type '<overloaded function type>'
    auto call = Call<int(int), int>;
         ^      ~~~~~~~~~~~~~~~~~~~
1 error generated.

gcc compiles the code in all cases.</pre>
        </div>
      </p>
      <hr>
      <span>You are receiving this mail because:</span>
      
      <ul>
          <li>You are on the CC list for the bug.</li>
      </ul>
    </body>
</html>