JustinStitt wrote:
> Regarding there not being a `no-wraps` attribute. What happens with code like
> this? Is the attribute lost / casted away during the addition?
>
> ```
> wrapping_int a = INT_MAX;
> a = (int) a + 1;
> ```
Good question, the attribute is cast away (intentionally so). Additionally,
sanitizers will warn of the overflow since the addition no longer contains a
wraps-annotated type/variable. The result of the addition is the same
regardless: `-2147483648`
> Does it affect converting a number too large to fit in the target type?
>
> ```
> wrapping_int a = INT_MAX;
> wrapping_short b = a;
> short c = a;
> ```
No, this attribute really doesn't modify any arithmetic. It just tells the
sanitizer not to instrument.
```c
wrapping_int a = INT_MAX;
wrapping_short b = a;
short c = a;
printf("%d\n%hd\n%hd\n", a, b, c);
/*
* 2147483647
* -1
* -1
*/
```
https://github.com/llvm/llvm-project/pull/86618
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