[clang] [Clang] Force expressions with UO_Not to not be non-negative (PR #126846)

[Erich Keane via cfe-commits]

erichkeane wrote:

> > This had the side effect of adding implicit-int-conversion warnings on e.g. the following code:
> > ```
> > unsigned char foo(unsigned char x)
> > {
> >     return ~x;
> > }
> > ```
> > 
> > 
> >     
> >       
> >     
> > 
> >       
> >     
> > 
> >     
> >   
> > This seems correct, but this should probably be highlighted in the release notes.
> > Another example is:
> > ```
> > unsigned int foo(unsigned char x)
> > {
> >     return ~(1<<x);
> > }
> > ```
> 
> Hi, could you edit the release note for me? I don't have write access, so I would have to submit a PR to do so. I don't think a PR with changes only in the release notes is a great idea.

Once you're merged there is no way to edit the release note other than a PR.  So whether or not it is a great idea, it is the only way to go :)   Please submit a PR to update it and we can all review the wording

https://github.com/llvm/llvm-project/pull/126846