[cfe-dev] [RFC] automatic variable initialization

[Tim Northover via cfe-dev]

Some very good points about mixing in 0s with the general case there.

On Fri, 16 Nov 2018 at 01:59, Chandler Carruth <chandlerc at google.com> wrote:
> FWIW, I agree about the zero case. I'm deeply concerned about fragmentation here.
>
> But I *also* really want to be able to get the data and measurements needed to address performance problems with non-zero initialization.

Yes, having a mechanism to get data does seem essential, but we need
to do everything we can to stop it being abused.

> I would love to see a way to get the zero initialization behavior for performance testing, but *not* expose this as a supported flag to users. I can imagine many ways to do that. Tim, would that address your concerns?

Yes; personally I think something stronger than a simple -cc1 flag is
probably needed to achieve that though. A (non-suppressible?) warning
comes to mind; mostly because I haven't come up with anything more
obnoxious yet.

Cheers.

Tim.