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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 - attribute ignored is a warning with gcc, an error with clang"
   href="https://bugs.llvm.org/show_bug.cgi?id=34304">34304</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>attribute ignored is a warning with gcc, an error with clang
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>5.0
          </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>enhancement
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Frontend
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>sylvestre@debian.org
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>This impacts a lot of qt programs:
<a href="http://clang.debian.net/status.php?version=5.0&key=NO_DISCARD_ATTRIBUTE">http://clang.debian.net/status.php?version=5.0&key=NO_DISCARD_ATTRIBUTE</a>

Simple example:
int a [[]];
int & [[nodiscard]] b = a;

$ clang++ -std=c++11 -c foo.cpp
foo.cpp:2:9: error: 'nodiscard' attribute cannot be applied to types
int & [[nodiscard]] b = a;
        ^
1 error generated.

$ g++ -std=c++11 -c foo.cpp
foo.cpp:2:20: warning: attribute ignored [-Wattributes]
 int & [[nodiscard]] b = a;
                    ^
foo.cpp:2:20: note: an attribute that appertains to a type-specifier is ignored

As we see clang as a drop-in replacement of gcc, maybe we should not trigger an
error here.</pre>
        </div>
      </p>


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