When using iostreams with pthreads, a deadlock occurs.  One thread may
write to a stream
just fine, but as soon as a second thread attempts to write to a stream, it
blocks on a
pthread mutex.  I have narrowed it down to the insertion of an endl into an
ostream.  As long
as an endl is not inserted, both threads can write to the stream.

Here is some sample code:

#include <iostream>
#include <unistd.h>
#include <pthread.h>

void* threadMain(void* data)
{
   while(1)
   {
      cout << "Thread" << endl;
      usleep(100);
   }
   return NULL;
}

int main()
{
   pthread_t thread;

   cout << "Creating thread" << endl;

   pthread_create(&thread, NULL, threadMain, NULL);

   pthread_join(thread, NULL);
}


This problem did not occur with older versions of libstdc++.

Thanks,
Brett Polivka