PVS-Studio warning V547 for Firefox

bool ExceptionHandler::WriteMinidumpForChild(....)
{
  ...
  DWORD last_suspend_cnt = -1;
  ...
  // this thread may have died already, so not opening
  // the handle is a non-fatal error
  if (NULL != child_thread_handle) {
    if (0 <=
        (last_suspend_cnt = SuspendThread(child_thread_handle)))
    {
  ...
}

Most likely this is what should be written here: (((DWORD) -1) != (last_suspend_cnt = SuspendThread(child_thread_handle))).


This suspicious code was found in Firefox project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression is always true. Unsigned type value is always >= 0. exception_handler.cc 846

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/