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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 - Cannot attach to a process with exited leader thread (TID==PID)"
   href="https://bugs.llvm.org/show_bug.cgi?id=47826">47826</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Cannot attach to a process with exited leader thread (TID==PID)
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>lldb
          </td>
        </tr>

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

        <tr>
          <th>Assignee</th>
          <td>lldb-dev@lists.llvm.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>jan.kratochvil@redhat.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>jdevlieghere@apple.com, llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>There does not need to exist a thread with TID equal to the process PID. That
TID could already exit while other TIDs of that PID may be still running.

<a href="https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=432b4d03ad0f23970315e9f9dec080ab4a9ab94b">https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=432b4d03ad0f23970315e9f9dec080ab4a9ab94b</a>

simplified and deGPLed as: <a href="https://people.redhat.com/jkratoch/leader-exit2.C">https://people.redhat.com/jkratoch/leader-exit2.C</a>

Currently LLDB server cannot attach to such TID as:
  lldb-server g --attach >TID< :1234
  ptrace(PTRACE_ATTACH, >PID<) = -1 EPERM (Operation not permitted)
  write(2, "error: failed to attach to pid >TID<: Operation not permitted\n",
64) = 64

02295e6d1a1559f0689aeca09d98f468e3f29d9a = 2020-10-12</pre>
        </div>
      </p>


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