PVS-Studio warning V549 for Micro-Manager

int XLedDev::Initialize()
{
  ....
  if (strcmp(
    XLed::Instance()->GetXLedStr(XLed::XL_WLedDevName +
                                 m_nLedDevNumber).c_str(),
    XLed::Instance()->GetXLedStr(XLed::XL_WLedDevName +
                                 m_nLedDevNumber).c_str()
            ) != 0)
  ....
}

This suspicious code was found in Micro-Manager project by PVS-Studio static code analyzer.
Warning message is:
V549 The first argument of 'strcmp' function is equal to the second argument. XLedDev.cpp 119

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/