Function gmp_mpfr_sys::gmp::__gmp_get_memory_functions

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