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### What it does
Checks for `MaybeUninit::uninit().assume_init()`.
### Why is this bad?
For most types, this is undefined behavior.
### Known problems
For now, we accept empty tuples and tuples / arrays
of `MaybeUninit`. There may be other types that allow uninitialized
data, but those are not yet rigorously defined.
### Example
```
// Beware the UB
use std::mem::MaybeUninit;
let _: usize = unsafe { MaybeUninit::uninit().assume_init() };
```
Note that the following is OK:
```
use std::mem::MaybeUninit;
let _: [MaybeUninit<bool>; 5] = unsafe {
MaybeUninit::uninit().assume_init()
};
```
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