Memory leak in String.Buffer

Imported from http://bugzilla.roxen.com/bugzilla/show_bug.cgi?id=2314

Reported by Jonas Wallden jonasw@roxen.com

Running this program will consume about 5-10 MB/sec.

int main()
{
  string str = "gurksallad" * 123;

  while(1) {
    for (int i = 0; i < 100; i++) {
      String.Buffer b = String.Buffer();
      b->add(str);
      b->get();          //  optional
    }
    gc();
  }
}