PVS-Studio warning V599 for WinMerge

CompareOptions *m_pCompareOptions;

CDiffContext::~CDiffContext()
{
  ...
  delete m_pCompareOptions;
  ...
}

class CompareOptions
{
public:
  CompareOptions();
  CompareOptions(const CompareOptions & options);
  virtual void SetFromDiffOptions(const DIFFOPTIONS & options);

  enum WhitespaceIgnoreChoices m_ignoreWhitespace;
  bool m_bIgnoreBlankLines;
  bool m_bIgnoreCase;
  bool m_bIgnoreEOLDifference;
};

class DiffutilsOptions : public CompareOptions
{
  ...
};

This suspicious code was found in WinMerge project by PVS-Studio static code analyzer.
Warning message is:
V599 The virtual destructor is not present, although the 'CompareOptions' class contains virtual functions. Merge diffcontext.cpp 90

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