rust/library/alloc/src at 00dfa3ba2d21577649e882ee65309fdbee08bf6d - rust

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T

bors 303e8bd768 Auto merge of #131193 - EFanZh:asserts-vec-len, r=the8472

Asserts the maximum value that can be returned from `Vec::len`

Currently, casting `Vec<i32>` to `Vec<u32>` takes O(1) time:

```rust
// See <https://godbolt.org/z/hxq3hnYKG> for assembly output.
pub fn cast(vec: Vec<i32>) -> Vec<u32> {
    vec.into_iter().map(|e| e as _).collect()
}
```

But the generated assembly is not the same as the identity function, which prevents us from casting `Vec<Vec<i32>>` to `Vec<Vec<u32>>` within O(1) time:

```rust
// See <https://godbolt.org/z/7n48bxd9f> for assembly output.
pub fn cast(vec: Vec<Vec<i32>>) -> Vec<Vec<u32>> {
    vec.into_iter()
        .map(|e| e.into_iter().map(|e| e as _).collect())
        .collect()
}
```

This change tries to fix the problem. You can see the comparison here: <https://godbolt.org/z/jdManrKvx>.

2024-12-22 16:09:16 +00:00

boxed

replace placeholder version

2024-11-27 12:10:21 +00:00

collections

Less unwrap() in documentation

2024-12-21 01:26:47 +00:00

ffi

Move some alloc tests to the alloctests crate

2024-12-04 14:32:04 +00:00

raw_vec

Polymorphize RawVec