How to give a structure with arrays in simulink to a custom C code function?

Question

I'm trying to give a structure to a C function in Simulink. My steps so far: - Included the `.h` & `.c` in configuration parameters custom code. My header has a structure defind: typedef struct mystruct { int m; int *i; double *x;}mystruct - Now in my MATLAB function under Simulink: function y = fcn(u)%#codegen m=int32(1); i=zeros(10,1,'int32'); x=zeros(10,1); s.m=m; s.i=i; s.x=x; coder.cstructname(s,'mystruct','extern'); D=int32(0); D=coder.ceval('accesmystruct',coder.ref(s)); y=10; If I run the code I get a long error from the code generation that indicates that it can't be compiled in c-code. The error is: c2_Test2.c c2_Test2.c(57) : error C2143: syntax error : missing ')' before '*' c2_Test2.c(57) : error C2081: 'cs_size' : name in formal parameter list illegal c2_Test2.c(57) : error C2143: syntax error : missing '{' before '*' c2_Test2.c(57) : error C2059: syntax error : ')' c2_Test2.c(60) : error C2143: syntax error : missing ')' before '*' .... This only happens if I declare the two variables `i` and `x` as Pointers. If I declare them as scalar in the header and MATLAB function it works. Does any one see what I'm doing wrong?

Answer 1

The issue is that the "zeros" function returns an array, and you are trying to bind an array to a pointer.

typedef struct mystruct {

int m;

//pointer type

int *i;

//pointer type

double *x;

} mystruct;

If you want to keep your definition of y, then update your struct to use arrays

typedef struct mystruct {

int m;

//array

int i[10];

//array

double x[10];

} mystruct;