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    <head>
      <base href="https://bugs.llvm.org/">
    </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 - Unused index call of zero-sized array with libcxx causes compile error"
   href="https://bugs.llvm.org/show_bug.cgi?id=36241">36241</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Unused index call of zero-sized array with libcxx causes compile error
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>new-bugs
          </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>new bugs
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>niravd@google.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=19812" name="attach_19812" title="failing test.">attachment 19812</a> <a href="attachment.cgi?id=19812&action=edit" title="failing test.">[details]</a></span>
failing test.

The following code no longer compiles with libcxx. It appears to be due to
r324182. 

error: non-const lvalue reference to type
      'std::__1::array<unsigned int, 0>::value_type' (aka 'unsigned int')
cannot bind to a value of unrelated type 'std::__1::aligned_storage<4,
4>::type'
    reference operator[](size_type __n)             {return __elems_[__n];}


Command: clang -stdlib=libc++  ~/foo.cc

#include <array>

template <size_t N>
void foo(std::array<uint32_t, N> x) {
  for (size_t i = 0; i < N; ++i)
    x[i] = x[i]++;
}


void bar() {
  foo(std::array<uint32_t, 0>());
  return;
}</pre>
        </div>
      </p>


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