Program: 169791
Project: 169791
Buggy source:
@Override public void update(EntityMissile missileObj){
  if (missileObj.feiXingTick > missileObj.missileFlightTime / 2 && missileObj.missileType == MissileType.missile) {
    WorldServer worldServer=(WorldServer)missileObj.worldObj;
    Entity trackingEntity=worldServer.getEntityByID(missileObj.trackingVar);
    if (trackingEntity != null) {
      if (trackingEntity == missileObj) {
        missileObj.setExplode();
      }
      missileObj.targetVector=new Vector3(trackingEntity);
      missileObj.missileType=MissileType.CruiseMissile;
      missileObj.deltaPathX=missileObj.targetVector.x - missileObj.posX;
      missileObj.deltaPathY=missileObj.targetVector.y - missileObj.posY;
      missileObj.deltaPathZ=missileObj.targetVector.z - missileObj.posZ;
      missileObj.flatDistance=Vector2.distance(missileObj.startPos.toVector2(),missileObj.targetVector.toVector2());
      missileObj.maxHeight=150 + (int)(missileObj.flatDistance * 1.8);
      missileObj.missileFlightTime=(float)Math.max(100,2.4 * missileObj.flatDistance);
      missileObj.acceleration=(float)missileObj.maxHeight * 2 / (missileObj.missileFlightTime * missileObj.missileFlightTime);
      if (missileObj.xiaoDanMotion.equals(new Vector3()) || missileObj.xiaoDanMotion == null) {
        float suDu=0.3f;
        missileObj.xiaoDanMotion=new Vector3();
        missileObj.xiaoDanMotion.x=missileObj.deltaPathX / (missileObj.missileFlightTime * suDu);
        missileObj.xiaoDanMotion.y=missileObj.deltaPathY / (missileObj.missileFlightTime * suDu);
        missileObj.xiaoDanMotion.z=missileObj.deltaPathZ / (missileObj.missileFlightTime * suDu);
      }
    }
  }
}

Fixed version (ground truth):
@Override public void update(EntityMissile missileObj){
  if (missileObj.feiXingTick > missileObj.missileFlightTime / 2 && missileObj.missileType == MissileType.missile) {
    WorldServer worldServer=(WorldServer)missileObj.worldObj;
    Entity trackingEntity=worldServer.getEntityByID(missileObj.trackingVar);
    if (trackingEntity != null) {
      if (trackingEntity.equals(missileObj)) {
        missileObj.setExplode();
      }
      missileObj.targetVector=new Vector3(trackingEntity);
      missileObj.missileType=MissileType.CruiseMissile;
      missileObj.deltaPathX=missileObj.targetVector.x - missileObj.posX;
      missileObj.deltaPathY=missileObj.targetVector.y - missileObj.posY;
      missileObj.deltaPathZ=missileObj.targetVector.z - missileObj.posZ;
      missileObj.flatDistance=Vector2.distance(missileObj.startPos.toVector2(),missileObj.targetVector.toVector2());
      missileObj.maxHeight=150 + (int)(missileObj.flatDistance * 1.8);
      missileObj.missileFlightTime=(float)Math.max(100,2.4 * missileObj.flatDistance);
      missileObj.acceleration=(float)missileObj.maxHeight * 2 / (missileObj.missileFlightTime * missileObj.missileFlightTime);
      if (missileObj.xiaoDanMotion.equals(new Vector3()) || missileObj.xiaoDanMotion == null) {
        float suDu=0.3f;
        missileObj.xiaoDanMotion=new Vector3();
        missileObj.xiaoDanMotion.x=missileObj.deltaPathX / (missileObj.missileFlightTime * suDu);
        missileObj.xiaoDanMotion.y=missileObj.deltaPathY / (missileObj.missileFlightTime * suDu);
        missileObj.xiaoDanMotion.z=missileObj.deltaPathZ / (missileObj.missileFlightTime * suDu);
      }
    }
  }
}