PVS-Studio warning V620 for Snes9x

typedef wchar_t TCHAR;

INT_PTR CALLBACK DlgOpenROMProc(....)
{
  ....
  TCHAR *tmp, *tmp2;
  ....
  while(tmp2=_tcsstr(tmp, TEXT("\\")))
    tmp=tmp2+sizeof(TCHAR);
  ....
}

Most likely this is what should be written here: tmp=tmp2+1;

This suspicious code was found in Snes9x project by PVS-Studio static code analyzer.
Warning message is:
V620 It's unusual that the expression of sizeof(T) kind is being summed with the pointer to T type. wsnes9x.cpp 6145

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/