Rollup merge of #97034 - fee1-dead-contrib:layout-hash, r=dtolnay

Implement `Hash` for `core::alloc::Layout`

This was brought up on [reddit](https://www.reddit.com/r/rust/comments/uoypui/the_standard_library_types_are_good_except_when/), and I don't see why Layout shouldn't implement `Hash`. Feel free to comment if I am wrong though :)
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Dylan DPC 2022-05-28 08:45:51 +02:00 committed by GitHub
commit 880d3ea3c2
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2 changed files with 9 additions and 2 deletions

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@ -26,7 +26,7 @@ const fn size_align<T>() -> (usize, usize) {
/// like this are met, use specific allocators with looser
/// requirements, or use the more lenient `Allocator` interface.)
#[stable(feature = "alloc_layout", since = "1.28.0")]
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
#[lang = "alloc_layout"]
pub struct Layout {
// size of the requested block of memory, measured in bytes.

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@ -1,6 +1,6 @@
use crate::convert::TryFrom;
use crate::num::NonZeroUsize;
use crate::{cmp, fmt, mem, num};
use crate::{cmp, fmt, hash, mem, num};
/// A type storing a `usize` which is a power of two, and thus
/// represents a possible alignment in the rust abstract machine.
@ -105,6 +105,13 @@ fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
}
}
impl hash::Hash for ValidAlign {
#[inline]
fn hash<H: hash::Hasher>(&self, state: &mut H) {
self.as_nonzero().hash(state)
}
}
#[cfg(target_pointer_width = "16")]
type ValidAlignEnum = ValidAlignEnum16;
#[cfg(target_pointer_width = "32")]