Why does GSL give error about mismatched dimension when there isn't one - c++

Question

I'm wrapping GSL's ODE functions is a class I'm defining. When written with no class involved, the functions are working perfectly. However, when using the class I get an error after the second gsl_odeiv2_evolve_apply_fixed_step, getting the error gsl: evolve.c:317: ERROR: step dimension must match evolution size. I'm confused why the first step should work but the second shouldn't. In printing out the dimension of the step and evolve functions I get the same thing. Here's what I have for my class and what I'm calling inside the main() function.
class DynSys {
public:
DynSys(const size_t size, double startTime, double endTime, double stepSize,
double* iState,
int (*func)(double, const double*, double*, void*),
int (*jac)(double, const double*, double*, double*, void*),
const gsl_odeiv2_step_type* T = gsl_odeiv2_step_rk8pd)
: T(T), size(size), t(startTime), t1(endTime), h(stepSize) {
y = new double[size];
y = iState;
yPrev = new double[size];
s = gsl_odeiv2_step_alloc(T, size);
c = gsl_odeiv2_control_y_new(1e-6, 0.0);
e = gsl_odeiv2_evolve_alloc(size);
sys = { func, jac, size, 0 };
}
~DynSys() {
delete [] y;
delete [] yPrev;
gsl_odeiv2_evolve_free(e);
gsl_odeiv2_control_free(c);
gsl_odeiv2_step_free(s);
}
void step() {
printf("e dim: %ld\n", e->dimension);
printf("s dim: %ld\n", s->dimension);
printf("y: %.5f %.5f %.5f %.5f %.5f %.5f\n", y[0], y[1],
y[2], y[3], y[4], y[5]);
tPrev = t;
yPrev = std::copy(y, y+size, yPrev);
int status = gsl_odeiv2_evolve_apply_fixed_step(e, c, s, &sys,
&t, h, y);
if (status != GSL_SUCCESS) {
printf("Error: %s\n", gsl_strerror(status));
throw std::logic_error(gsl_strerror(status));
}
}
double getT() {
return t;
}
void setY(double* y) {
y = y;
}
private:
const gsl_odeiv2_step_type* T;
gsl_odeiv2_step* s;
gsl_odeiv2_control* c;
gsl_odeiv2_evolve* e;
gsl_odeiv2_system sys;
const size_t size;
double t;
double t1;
double h;
double* y;
double tPrev;
double* yPrev;
};
and then
int main() {
double state[] = { 1.0, 0.0, 0.0, 0.796975, 0.11637, 0.0185312};
const size_t size = 6;
DynSys system(size, 0.0, 40.0, 1e-3, state, func, jac);
system.step();
printf("t: %.5f\n", system.getT());
system.step();
printf("t: %.5f\n", system.getT());
return 0;
}
edit: Here's a link to the GSL functions GSL ODE