PVS-Studio warning V543 for WinMerge

static HRESULT safeInvokeA(LPDISPATCH pi, VARIANT *ret,
                           DISPID id, LPCCH op, ...)
{
  HRESULT h;
  ...
  // set h to FAILED
  h = -1;
  ...
}

This suspicious code was found in WinMerge project by PVS-Studio static code analyzer.
Warning message is:
V543 It is odd that value '-1' is assigned to the variable 'h' of HRESULT type. Merge plugins.cpp 992

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