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    <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 --- - [regression] libstdc++4.9 get tuple element by type broke"
   href="https://llvm.org/bugs/show_bug.cgi?id=27601">27601</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>[regression] libstdc++4.9 get tuple element by type broke
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>trunk
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>All
          </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>C++14
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>gonzalobg88@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>The following code compiles fine with clang@264182 and libstdc++4.9 (which
supports C++14 get tuple element by type) using: clang++ -std=c++14 file.cpp

#include <tuple>

int main() {
  std::tuple<int, double, char> t;
  std::get<double>(t);
  return 0;
}

But breaks with the following error message on clang trunk (268219):

~/test> clang++ -std=c++14 file.cpp 
In file included from file.cpp:1:
/usr/lib64/gcc/x86_64-suse-linux/4.9/../../../../include/c++/4.9/tuple:791:14:
error: no matching function for call to '__get_helper2'
    { return std::__get_helper2<_Tp>(__t); }
             ^~~~~~~~~~~~~~~~~~~~~~~
file.cpp:5:8: note: in instantiation of function template specialization
'std::get<double, int, double, char>' requested here
  std::get<double>(t);
       ^
/usr/lib64/gcc/x86_64-suse-linux/4.9/../../../../include/c++/4.9/tuple:779:5:
note: candidate template ignored: deduced type '_Tuple_impl<3UL, double> &' of
1st parameter does not
      match adjusted type 'tuple<int, double, char>' of argument [with _Head =
double, __i = 3, _Tail = <>]
    __get_helper2(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
    ^
/usr/lib64/gcc/x86_64-suse-linux/4.9/../../../../include/c++/4.9/tuple:784:5:
note: candidate template ignored: deduced type 'const _Tuple_impl<3UL, double>
&' of 1st parameter does
      not match adjusted type 'tuple<int, double, char>' of argument [with
_Head = double, __i = 3, _Tail = <>]
    __get_helper2(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
    ^
1 error generated.</pre>
        </div>
      </p>
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