Optimize `Layout::array`.

The current implementation is much more conservative than it needs to
be, because it's dealing with the size and alignment of a given `T`,
which are more restricted than an arbitrary `Layout`.

For example, imagine a struct with a `u32` and a `u4`. You can safely
create a `Layout { size_: 5, align_: 4 }` by hand, but
`Layout::new::<T>` will give `Layout { size_: 8, align_: 4}`, where the
size already has padding that accounts for the alignment. (And the
existing `debug_assert_eq!` in `Layout::array` already demonstrates that
no additional padding is required.)

0 files changed, 0 insertions, 0 deletions