PVS-Studio warning V636 for Geant4

G4double G4XAqmTotal::CrossSection(
  const G4KineticTrack& trk1, const G4KineticTrack& trk2) const
{
  ....
  G4int sTrk1 = ....;
  G4int qTrk1 = ....;

  G4double sRatio1 = 0.;
  if (qTrk1 != 0) sRatio1 = sTrk1 / qTrk1;
  ....
}

This suspicious code was found in Geant4 project by PVS-Studio static code analyzer.
Warning message is:
V636 The 'sTrk1 / qTrk1' expression was implicitly casted from 'int' type to 'double' type. Consider utilizing an explicit type cast to avoid the loss of a fractional part. An example: double A = (double)(X) / Y;. g4xaqmtotal.cc 103

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