Although the CComBSTR = operator is overloaded to make a copy of the string, this is not the case when assigning a CComVariant’s bstrVal member to a CComBSTR. In this case, you need to make an explicit copy:
CComVariant bstrTarget;CComBSTR strSource("test");// Use CComBSTR::Copy to make a copy// of the source string.bstrTarget.bstrVal = strSource.Copy();
If you don’t make a copy of the source string, it will wind up being freed twice?once by the CComVariant‘s destructor, and once by the original CComBSTR‘s destructor.