PVS-Studio warning V530 for WinMerge

/**
* @brief Clear variant's value (reset to defaults).
*/
void VariantValue::Clear()
{
  m_vtype = VT_NULL;
  m_bvalue = false;
  m_ivalue = 0;
  m_fvalue = 0;
  m_svalue.empty();
  m_tvalue = 0;
}

This is what should have been written here: m_svalue.clear();

This suspicious code was found in WinMerge project by PVS-Studio static code analyzer.
Warning message is:
V530 The return value of function 'empty' is required to be utilized

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/