Fixed a compilation error when not using entropy. This is a temporary workaround. There is no model solution for hydro only, therefore autotesting will break if entropy is not used. Note: LINDUCTION, LENTROPY and other logical flags are duplicated in both astaroth.h and stencil_process.sps. These flags are not linked and there will be errors and weird behaviour if a flag is set in one file and not in another.

src/standalone/model/model_rk3.cc

@@ -616,8 +616,9 @@ momentum(const ModelVectorData& uu, const ModelScalarData& lnrho
               (laplace_vec(uu) + ModelScalar(1. / 3.) * gradient_of_divergence(uu) +
                ModelScalar(2.) * mul(S, gradient(lnrho))) + get(AC_zeta) * gradient_of_divergence(uu);
     //#endif
-#endif
     return mom;
+#endif
+    return (ModelVector){NAN, NAN, NAN}; // TODO HYDRO ONLY MODEL SOLUTION
 }
 
 static inline ModelVector