PVS-Studio warning V502 for TinyCAD

BOOL hasOrigin;

void Ruler::OnNewSize(CRect nSize)
{
  ....
  Size = CRect(Size.left + hasOrigin ? RULER_WIDTH : 0,
               Size.top, Size.right, Size.top + RULER_WIDTH);
  ....
}

This suspicious code was found in TinyCAD project by PVS-Studio static code analyzer.
Warning message is:
V502 Perhaps the '?:' operator works in a different way than it was expected. The '?:' operator has a lower priority than the '+' operator. ruler.cpp 66

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/