cannot convert parameter 1 from 'QVariant' to 'VARIANT'

[loh]

hi, why i have this error? there's my code:

QAxObject ao;
ao.setControl("geometry.geometryenvironment");
 
IGeometryEnvironmentPtr ipGeoEnviron(CLSID_GeometryEnvironment);
IGeometryFactory2Ptr ipGeomFact(ipGeoEnviron);
 
ao.queryInterface(IID_IGeometryFactory2,(void**)&ipGeomFact);
 
IGeometryPtr ipGeom;
 
QVariant value = query.value(0);
 
if (ipGeomFact){
 long bytesRead;
 if (ipGeomFact->CreateGeometryFromWkbVariant(value, &ipGeom, &bytesRead)))
}

QAxObject ao;
ao.setControl("geometry.geometryenvironment");

IGeometryEnvironmentPtr ipGeoEnviron(CLSID_GeometryEnvironment);
IGeometryFactory2Ptr ipGeomFact(ipGeoEnviron);

ao.queryInterface(IID_IGeometryFactory2,(void**)&ipGeomFact);

IGeometryPtr ipGeom;

QVariant value = query.value(0);

if (ipGeomFact){
 long bytesRead;
 if (ipGeomFact->CreateGeometryFromWkbVariant(value, &ipGeom, &bytesRead)))
}

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VARIANT type is supported COM datataype, but as i understand it's supported only with calling methods using dynamicCall, i cant use dynamicCall because there's parameters of unsupported datatypes in CreateGeometryFromWkbVariant function:

HRESULT CreateGeometryFromWkbVariant(
  VARIANT wkb,
  IGeometry** outGeometry,
  long* numBytesRead
);

HRESULT CreateGeometryFromWkbVariant(
  VARIANT wkb,
  IGeometry** outGeometry,
  long* numBytesRead
);

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so maybe i need to convert QVariant to VARIANT, but how?