Using loadlibrary and calllib functions, problem with calling struct arrays

Hi,

I'm trying to call some exposed functions in a shared library (.so), with Matlab 2019b.

I have a struct definition, with itself contains a struct array that is composed of some other structs, like this:

typedef float xx[2];

typedef struct {

float a;

float b;

struct xx;

} rand1_a[4];

typedef struct {

rand1_a yy;

} rand2;

When I'm using the calllib, I'm getting the error:

"Cannot convert data value for field yy due to error:

Only structure arrays of simple data types are supported"

Is there a nice solution for this? THanks in advance

Regards

Goksan