Function guile_sys::__gmp_get_memory_functions

pub unsafe extern "C" fn __gmp_get_memory_functions(
    arg1: *mut Option<extern "C" fn(_: size_t) -> *mut c_void>, 
    arg2: *mut Option<unsafe extern "C" fn(_: *mut c_void, _: size_t, _: size_t) -> *mut c_void>, 
    arg3: *mut Option<unsafe extern "C" fn(_: *mut c_void, _: size_t)>
)