diff --git a/opm/autodiff/FullyImplicitBlackoilSolver_impl.hpp b/opm/autodiff/FullyImplicitBlackoilSolver_impl.hpp
index 12cb372ef..52bd1ec2c 100644
--- a/opm/autodiff/FullyImplicitBlackoilSolver_impl.hpp
+++ b/opm/autodiff/FullyImplicitBlackoilSolver_impl.hpp
@@ -530,10 +530,10 @@ namespace {
 
             if (active_[ Gas]) {
                 // Define Sg Rs and Rv in terms of xvar.
-                ADB rsSat = fluidRsSat(state.pressure, cells_);
-                ADB rvSat = fluidRvSat(state.pressure, cells_);
-                ADB xvar = vars[ nextvar++ ];
-                ADB sg = isSg*xvar + isRv* so;
+                const ADB& rsSat = fluidRsSat(state.pressure, cells_);
+                const ADB& rvSat = fluidRvSat(state.pressure, cells_);
+                const ADB& xvar = vars[ nextvar++ ];
+                const ADB& sg = isSg*xvar + isRv* so;
                 state.saturation[ pu.phase_pos[ Gas ] ] = sg;
                 so = so - sg;