potential missing eval

Former-commit-id: c7b9712a4ab8fead800f64483e302028fe850f48

include/igl/arap_dof.cpp

@@ -149,7 +149,7 @@ IGL_INLINE bool igl::arap_dof_precomputation(
   // Apply group sum to each dimension's block of covariance scatter matrix
   SparseMatrix<double> G_sum_dim;
   repdiag(G_sum,data.dim,G_sum_dim);
-  CSM = G_sum_dim * CSM;
+  CSM = (G_sum_dim * CSM).eval();
 #ifdef EXTREME_VERBOSE
   cout<<"CSMIJV=["<<endl;print_ijv(CSM,1);cout<<endl<<"];"<<
     endl<<"CSM=sparse(CSMIJV(:,1),CSMIJV(:,2),CSMIJV(:,3),"<<