pub unsafe fn set_allocator(
new_malloc: Option<unsafe extern "C" fn(usize) -> *mut c_void>,
new_calloc: Option<unsafe extern "C" fn(usize, usize) -> *mut c_void>,
new_realloc: Option<unsafe extern "C" fn(*mut c_void, usize) -> *mut c_void>,
new_free: Option<unsafe extern "C" fn(*mut c_void)>,
)