debug error using struct

[pappala]

I tried to execute the following code...

#include "def_struct.c"
int main()
{
float Max_Eval;
int level =0;
result=PSO(level, Max_Eval);
}
where pso is a structure
struct position PSO(int level, float Max_Eval)
{
int add_option=1;
int already;
.........
}

and struct position is defined in def_struct.c
struct position {struct vector p;struct f f;};
struct position PSO(int level, float Max_Eval);

When I debug the code,the program throws an exception while trying to call pso.Can anyone help me in this regard.