why does " long long * " in c program make error?

[11hours]

double user_pid_ctrl(struct MotorData *Mptr)
{
    static double    *t_f64;
    static long long *t_i64;

    t_f64 = (double*)pushm;
    t_i64 = (long long*)pushm;

    pshm->P[4096] = (double)t_f64[8];   // success
    pshm->P[4097] = (double)t_i64[8];   // makes error

    t_f64 = (double*)(&(pshm->ModbusServerBuffer[512]));
    t_i64 = (long long*) (&(pshm->ModbusServerBuffer[512]));

    pshm->P[4096] = (double)t_f64[8];   // success
    pshm->P[4097] = (double)t_i64[8];   // makes error

    return 0;
}

I put the codes in function "user_pid_ctrl" in "usrcode.c", and I found that if I used a "long long *" pointer point to pushm or ModbusServerBuffer, the IDE reports error as follow:

[PMAC_PROJECT]
Error: Loading usralgo.ko
Error: Loading RT Address of user_pid_ctrl
Error: Loading RT Address of user_pid_ctrl
Warning: Loading RT Address of CfromScript
Warning: Loading RT Address of CaptCompISR

I think IDE does not report the exact reason, but I can not find any log file of any compile errors. 

The error just happens when I use "long long *" or "unsigned long long *". Everything runs well with any type of 4bytes, even with 8bytes "double". 

Why?

My PMAC is CK3M, CPU is arm,LS1021A, kernel is 4.1.18-ipipe, firmware 2.7.00. 

My Pc is windows10 64 bit.

Edited September 21 by 11hours

[steve.milici]

PMAC C-programming does not support the “long long” integer type.

[MoMo]

As Steve mentioned, the PPMAC servo algorithm considers operational efficiency and does not support the standard C library functions, so the type casting you're currently doing is not usable in user-written servo algorithms.

[steve.milici]

I would need to see the text of the error but casting a “long long” to a “double” may end up with a conversion that “Realtime Routines” cannot use. This should work in “Background Programs” though.

[11hours]

Thanks, guys!

On 9/24/2024 at 10:01 PM, MoMo said:

As Steve mentioned, the PPMAC servo algorithm considers operational efficiency and does not support the standard C library functions, so the type casting you're currently doing is not usable in user-written servo algorithms.

 

On 9/24/2024 at 11:07 PM, steve.milici said:

I would need to see the text of the error but casting a “long long” to a “double” may end up with a conversion that “Realtime Routines” cannot use. This should work in “Background Programs” though.

 

On 9/24/2024 at 1:45 AM, steve.milici said:

PMAC C-programming does not support the “long long” integer type.