title: Help interpret this stack trace
body: <p>I know that it fails at strcmp. I've provided operator&lt; below, which calls strcmp. </p>
  
  <p>On line #1 there's the value @0xbfffeeac. What does the @ mean?</p>
  
  <pre><code>#0  0x00212bd8 in strcmp () from /lib/libc.so.6
  #1  0x0012ed2f in Json::Value::CZString::operator&lt; (this=0x8317300, other=@0xbfffeeac)
      at src/lib_json/json_value.cpp:221
  #2  0x001361b0 in std::less&lt;Json::Value::CZString&gt;::operator() (this=0x83173a0, __x=@0x8317300, 
      __y=@0xbfffeeac)
      at /usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/stl_function.h:230
  #3  0x00136101 in std::_Rb_tree&lt;Json::Value::CZString, std::pair&lt;Json::Value::CZString const, Json::Value&gt;, std::_Select1st&lt;std::pair&lt;Json::Value::CZString const, Json::Value&gt; &gt;, std::less&lt;Json::Value::CZString&gt;, std::allocator&lt;std::pair&lt;Json::Value::CZString const, Json::Value&gt; &gt; &gt;::_M_lower_bound (this=0x83173a0, 
      __x=0x83172f0, __y=0x83173a4, __k=@0xbfffeeac)
      at /usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/stl_tree.h:986
  #4  0x001348da in std::_Rb_tree&lt;Json::Value::CZString, std::pair&lt;Json::Value::CZString const, Json::Value&gt;, std::_Select1st&lt;std::pair&lt;Json::Value::CZString const, Json::Value&gt; &gt;, std::less&lt;Json::Value::CZString&gt;, std::allocator&lt;std::pair&lt;Json::Value::CZString const, Json::Value&gt; &gt; &gt;::find (this=0x83173a0, __k=@0xbfffeeac)
      at /usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/stl_tree.h:1421
  #5  0x0013383a in std::map&lt;Json::Value::CZString, Json::Value, std::less&lt;Json::Value::CZString&gt;, std::allocator&lt;std::pair&lt;Json::Value::CZString const, Json::Value&gt; &gt; &gt;::find (this=0x83173a0, __x=@0xbfffeeac)
      at /usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/stl_map.h:659
  #6  0x00131779 in Json::Value::operator[] (this=0x8317280, key=0xbfffef74 "col1")
      at src/lib_json/json_value.cpp:1055
  #7  0x00131ba8 in Json::Value::isMember (this=0x8317280, key=0xbfffef74 "col1")
      at src/lib_json/json_value.cpp:1169
  #8  0x0805cf4d in CFG::CFG_Fetch_Raw (this=0x825846c, section=0x8317280, key=0xbfffef74 "col1", defval=0x0)
      at CFG.cpp:48
  #9  0x08050e5b in Generic::CFGSetup (this=0x825846c, k=0x8255e2c "display_qt") at Generic.cpp:89
  #10 0x0804df6a in LCDControl::ConfigSetup (this=0xbffff2a8) at LCDControl.cpp:81
  #11 0x0804d93b in LCDControl::Start (this=0xbffff2a8, argc=1, argv=0xbffff404) at LCDControl.cpp:15
  #12 0x0804f224 in main (argc=1, argv=0xbffff404) at Main.cpp:7
  
  bool
  Value::CZString::operator&lt;( const CZString &amp;other ) const
  {
     if ( cstr_ )
        return strcmp( cstr_, other.cstr_ ) &lt; 0; //src/lib_json/json_value.cpp:221
     return index_ &lt; other.index_;
  }
  </code></pre>