<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 --- - undefined-inline warning when constexpr is used"
   href="http://llvm.org/bugs/show_bug.cgi?id=16329">16329</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>undefined-inline warning when constexpr is used
          </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>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++11
          </td>
        </tr>

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

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

        <tr>
          <th>CC</th>
          <td>dgregor@apple.com, llvmbugs@cs.uiuc.edu
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>stephen@hal:/tmp$ clang++ --version
Ubuntu clang version 3.2-1~exp9ubuntu1 (tags/RELEASE_32/final) (based on LLVM
3.2)
Target: x86_64-pc-linux-gnu
Thread model: posix

stephen@hal:/tmp$ clang++ -std=c++11 -DUSE_CONSTEXPR -c test.cpp 

stephen@hal:/tmp$ clang++ -std=c++11 -c test.cpp 

stephen@hal:/tmp$ ~/dev/build/qtbase/llvm/bin/clang++ --version
clang version 3.4 
Target: x86_64-unknown-linux-gnu
Thread model: posix

stephen@hal:/tmp$ ~/dev/build/qtbase/llvm/bin/clang++ -std=c++11
-DUSE_CONSTEXPR -c test.cpp
test.cpp:9:20: warning: inline function 'typeId<A>' is not defined
[-Wundefined-inline]
DECL_CONSTEXPR int typeId();
                   ^
test.cpp:19:15: note: used here
        (void)typeId<A>();
              ^
1 warning generated.

stephen@hal:/tmp$ ~/dev/build/qtbase/llvm/bin/clang++ -std=c++11 -c test.cpp

stephen@hal:/tmp$ g++ --version
g++ (Ubuntu/Linaro 4.7.3-1ubuntu1) 4.7.3
Copyright (C) 2012 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


stephen@hal:/tmp$ g++ -std=c++11 -DUSE_CONSTEXPR -c test.cpp

stephen@hal:/tmp$ g++ -std=c++11 -c test.cpp

stephen@hal:/tmp$ cat test.cpp 

#ifdef USE_CONSTEXPR
#define DECL_CONSTEXPR constexpr
#else
#define DECL_CONSTEXPR
#endif

template <typename T>
DECL_CONSTEXPR int typeId();

struct A {};

template<typename T>
struct Template
{
    static void registerType(T t)
    {
        t.does_not_compile;
        (void)typeId<A>();
    }
};

template <typename T>
DECL_CONSTEXPR int typeId()
{
    return 0;
}

void avoidWarning()
{
//     (void)typeId<A>();
}


The warning is not emitted if the contents of avoidWarning are uncommented.</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>