PVS-Studio warning V575 for ReactOS

DWORD ParseReasonCode(LPCWSTR code)
{
  LPWSTR tmpPrefix = NULL;
  ....
  for (reasonptr = shutdownReason ;
       reasonptr->prefix ; reasonptr++)
  {
    if ((majorCode == reasonptr->major) &&
        (minorCode == reasonptr->minor) &&
        (_wcsicmp(tmpPrefix, reasonptr->prefix) != 0))
    {
      return reasonptr->flag;
    }
  }
  ....
}

This suspicious code was found in ReactOS project by PVS-Studio static code analyzer.
Warning message is:
V575 The null pointer is passed into '_wcsicmp' function. Inspect the first argument. misc.c 150

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/