((char *) pDest)++;

typedef struct _S_usb S_usb;

......
//идет определение типов типа такого
typedef void (*S_usb_reset)(const S_usb *);
//ну и потом таблица колбеков из такиз типов

//далее в том же файле
typedef struct _S_usb {

    const S_usb_driver     *pDriver;        //!< Pointer to the low-level driver
    S_usb_endpoint* const   pEndpoints;     //!< Endpoints list
    unsigned int            dNumEndpoints;  //!< Number of endpoints in list
    const S_usb_callbacks  *pCallbacks;     //!< Pointer to the callbacks
    S_usb_request* const    pSetup;         //!< \brief Pointer to the last
                                            //!< received SETUP packet
    volatile unsigned int* const pState;    //!< Current state of the device
} S_usb;

4.5:    I have a char * pointer that happens to point to some ints, and
        I want to step it over them.  Why doesn't

                ((int *)p)++;

        work?

A:      In C, a cast operator does not mean "pretend these bits have a
        different type, and treat them accordingly"; it is a conversion
        operator, and by definition it yields an rvalue, which cannot be
        assigned to, or incremented with ++.  (It is either an accident
        or a delibrate but nonstandard extension if a particular
        compiler accepts expressions such as the above.)  Say what you
        mean: use

                p = (char *)((int *)p + 1);

        or (since p is a char *) simply

                p += sizeof(int);

        Whenever possible, you should choose appropriate pointer types
        in the first place, instead of trying to treat one type as
        another.

        References: K&R2 Sec. A7.5 p. 205; ISO Sec. 6.3.4; Rationale
        Sec. 3.3.2.4; H&S Sec. 7.1 pp. 179-80.