[讨论]UDF编译解释

279536328

#include "udf.h"
DEFINE_CG_MOTION(piston, dt, vel, omega, time, dtime)
{
  Thread *t;
  face_t f;
  real NV_VEC (A);
  real force, dv;
  real v_prev = 0.0;
  /* reset velocities */
  NV_S (vel, =, 0.0);
  NV_S (omega, =, 0.0);
  if (!Data_Valid_P ())
    return;
  /* get the thread pointer for which this motion is defined */
  dt=4;
  /* compute pressure force on body by looping through all faces */
  force = 0.0;
  begin_f_loop (f, t)
    {
      F_AREA (A, f, t);
      force += F_P (f, t) * NV_MAG (A);
    }
  end_f_loop (f, t)
  /* compute change in velocity, i.e., dv = F * dt / mass
     velocity update using explicit Euler formula */
  dv = dtime * force / 50.0;
  v_prev += dv;
  Message ("time = %f, x_vel = %f, force = %f\n", time, v_prev,
  force);
  /* set x-component of velocity */
  vel[0] = v_prev;
}

这个UDF用interpret没问题，但是compile却报错？
咋回事亚？