CCS/TMS320F28335: Struct upcasting and offsetof macro

Tool/software: Code Composer Studio

Hi everybody,

in my application I am using this compounded structure:

typedef struct binary_i binary_i_t; 

struct binary_i {
    binary_t binaryClass;   /*!< Binary class >*/
    QFsm super[NUMBER_OF_BI];           /*!< QFsm super class >*/
    bi_ctl_t biCtlQFsm[NUMBER_OF_BI];   /*!< Binary input control register >*/
};

In the code there is a function, which launches binary scanning finite state machine: 

BinaryFSM_Process(QFsm *const me) {
binary_i_t *bme = ((char*)me - offsetof(binary_i_t, super[FSM_number]));
....
}

  Mentioned function is invoked by this way:

BinaryFSM_Process(&BIN_scanner.biFSM[FSM_number]);

In this function I need to upcast me pointer to binary_i_t structure. Firstly, I have tried to solve it in Code::Block on my PC - with offsetof macro and (char*) upcasting, please,  see this piece of code:

binary_i_t *bme = ((char*)me - offsetof(binary_i_t, super[FSM_number]));

It has been working correctly, in accordance with my wishes.

However, when I attempted to realize it in CCS6, this error was appeared: #28: expression must have a constant value. In my opinion, probably due to variable FSM_number.

At the moment I don't know, how to fix it. Is there any other method to upcast me pointer to binary_i_t structure, for exaple without offsetof macro? Why CCS6 generates error mentioned above?

Thank you a lot.