message: Round vector_downward initial size up
diff: @@ -496,12 +496,11 @@ class vector_downward {
  public:
  explicit vector_downward(size_t initial_size,
  const simple_allocator &allocator)
  - : reserved_(initial_size),
  + : reserved_((initial_size + sizeof(largest_scalar_t) - 1) &
  + ~(sizeof(largest_scalar_t) - 1)),
  buf_(allocator.allocate(reserved_)),
  cur_(buf_ + reserved_),
  - allocator_(allocator) {
  - assert((initial_size & (sizeof(largest_scalar_t) - 1)) == 0);
  - }
  + allocator_(allocator) {}
  ~vector_downward() {
  if (buf_)
  