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      <base href="https://bugs.llvm.org/">
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - GDB remote protocol 'A' packet format is not spec-compliant"
   href="https://bugs.llvm.org/show_bug.cgi?id=42471">42471</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>GDB remote protocol 'A' packet format is not spec-compliant
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>8.0
          </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>All Bugs
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>spmichaels.work@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>jdevlieghere@apple.com, llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>LLDB's GDB remote protocol implementation defines a parser for the 'A' packet
at tools/debugger/source/RNBRemote.cpp:1538 (i.e. RNBRemote::HandlePacket_A()).
This packet is used to pass an argv[] array to the program.

GDB's remote protocol spec defines the A packet as follows (see
(<a href="https://sourceware.org/gdb/onlinedocs/gdb/Packets.html">https://sourceware.org/gdb/onlinedocs/gdb/Packets.html</a>):

---
‘A arglen,argnum,arg,…’

Initialized argv[] array passed into program. arglen specifies the number of
bytes in the hex encoded byte stream arg. See gdbserver for more details.
---

Note that `gdbserver` does not actually implement the A packet (see
<a href="https://github.com/bminor/binutils-gdb/blob/master/gdb/gdbserver/server.c">https://github.com/bminor/binutils-gdb/blob/master/gdb/gdbserver/server.c</a>), so
the note to "See gdbserver for more details" is moot.


LLDB's implementation assumes that 'arglen' and 'argnum' are base-10 unsigned
integers. However, the GDB remote protocol overview specifies that (see
<a href="https://sourceware.org/gdb/onlinedocs/gdb/Overview.html#Overview">https://sourceware.org/gdb/onlinedocs/gdb/Overview.html#Overview</a>):

---
Except where otherwise noted all numbers are represented in HEX with leading
zeros suppressed.
---

Since the 'A' packet definition does not explicitly specify a base for arglen
and argnum, thesei should actually be base-16, not base-10 as they are now.

This would require changes to the two `strtoul()` calls on lines 1562 and 1574
of `RNBRemote.cpp`.</pre>
        </div>
      </p>


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