Monitor destructor...

[Peter Helfer]

Hi all

I've got some funny error I'm running into: In order to see what deadlocks
I'm creating, I extended the Monitor (Mutex) constructor to copy the "name"
parameter, instead of keeping it at "UNKNOWN" (as of ClearMonitor).

class Monitor{
...
char * _name;                    // Name of mutex REMOVED const!
..
};
static const char* Monitor::_default = "UNKNOWN";


void Monitor::ClearMonitor (Monitor * m) {
  m->_owner             = NULL ;
  m->_snuck             = false ;
  m->_name              = (char*) Monitor::_default;
  m->_LockWord.FullWord = 0 ;
  m->_EntryList         = NULL ;
  m->_OnDeck            = NULL ;
  m->_WaitSet           = NULL ;
  m->_WaitLock[0]       = 0 ;
}

Monitor::Monitor() { ClearMonitor(this); }

Monitor::Monitor (int Rank, const char * name, bool allow_vm_block) {
  ClearMonitor (this) ;
#ifdef ASSERT
  if(name){
        int len            = strnlen(name,63);
        _name              = NEW_C_HEAP_ARRAY(char,len+1);
        assert(_name, "Not enough mem");
        strncpy(_name, name, len+1);
  }
  _allow_vm_block  = allow_vm_block;
  _rank            = Rank ;
#endif
}

Monitor::~Monitor() {
  assert
((UNS(_owner)|UNS(_LockWord.FullWord)|UNS(_EntryList)|UNS(_WaitSet)|UNS(_OnDeck))
== 0, "") ;
  #ifdef ASSERT
  if(_name != _default){
        FreeHeap(_name);
  }
  #endif
}

This is what I am seeing: it only doesnt work in this situation.. The easy
work around is to remove the code again, but thats actually not the idea..
:-)

/home/peterh/workspace/openjdk/control/build/linux-i586-debug/bin/java
-client -Xmx881m -Xms128m -XX:PermSize=32m -XX:MaxPermSize=160m -classpath
/home/peterh/workspace/openjdk/control/build/linux-i586-debug/tmp/meta-index
BuildMetaIndex -o meta-index *.jar
VM option 'PermSize=32m'
VM option 'MaxPermSize=160m'
## nof_mallocs = 19744, nof_frees = 12802
## memory stomp: byte at 0x8189648 in front of object 0x8189660
### previous object (not sure if correct): 0x8189648 (73 bytes)
### next object (not sure if correct): 0x8189694 (1700358998 bytes)
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc:  SuppressErrorAt=/os.cpp:544
#
# An unexpected error has been detected by Java Runtime Environment:
#
#  Internal Error
(/home/peterh/workspace/openjdk/hotspot/src/share/vm/runtime/os.cpp:544),
pid=7146, tid=2209852304
#  Error: memory stomping error
#
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