I also think that code will run fine. The comment in LibreOffice's source and this blog post are incorrect.

I also wonder how far PVS-Studio goes in deciding that 'expression is always true' in this fragment:

  if( (pSymDef->GetType() != SbxEMPTY) ||
      (pSymDef->GetType() != SbxNULL) )

Is ::GetType() marked as pure in the LibreOffice source code, does PVS-Studio check the source code of its implementation(s), does PVS-Studio have heuristics for function names that likely are pure, or does it just assume any function is pure?