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      <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 - Block destructor calls destructor on variable captured by reference"
   href="https://bugs.llvm.org/show_bug.cgi?id=40330">40330</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Block destructor calls destructor on variable captured by reference
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Macintosh
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>MacOS X
          </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>C++
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>sebastian@theophil.net
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>blitzrakete@gmail.com, dgregor@apple.com, erik.pilkington@gmail.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=21335" name="attach_21335" title="Reproduction">attachment 21335</a> <a href="attachment.cgi?id=21335&action=edit" title="Reproduction">[details]</a></span>
Reproduction

In the attached reproduction, 

- I create an object T on the stack, 
- then capture this object by reference in a lambda
- and in the lambda create a block that again captures this t by reference. 

This seems correct so far because at the point of creation, object T is a
reference. 

Then I convert the (stack allocated) block to a heap allocated block using
_Block_copy and release it using _Block_release. This tries to call the
destructor on the reference to T, which seems to be a bug.

The bug occurs on the latest version of clang for Xcode which reports itself as 
Apple LLVM version 10.0.0 (clang-1000.11.45.2)</pre>
        </div>
      </p>


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