     
     __syncthreads();
 
+    printf("here ...0\n");
+
     double maxcfl = 0;
 
     int ifaces_x = mx + 2*mbc-1;

                auxd[m] = aux[I_aux - ys];
            }               

            rpn2(1, meqn, mwaves, maux, qd, qr, auxd, auxr, wave, s, bmdq, bpdq);

            /* Set value at bottom interface of cell I */
            for (int mq = 0; mq < meqn; mq++) 

                auxl[m] = aux[I_aux - 1];
            }               

            printf("here ...0a\n");

            rpn2(0, meqn, mwaves, maux, ql, qr, auxl, auxr, wave, s, amdq, apdq);
            printf("here ...0b\n");

            for (int mq = 0; mq < meqn; mq++) 
            {
