Re: [RFC PATCH] tools/memory-model: Remove (dep ; rfi) from ppo

[Peter Zijlstra]

On Tue, Feb 26, 2019 at 06:28:45AM -0800, Paul E. McKenney wrote:
> I must confess to not being all that sympathetic to code that takes
> advantage of happenstance stack-frame layout.  Is there some reason
> we need that?

Not that I'm aware; but if it gets this 'obvious' case wrong, I worry
what else it gets wrong.

At the very least we should get this fixed and compile a kernel with the
fixed compiler to see what (if anything) changes in the generated code
and analyse the changes (if any) to make sure we were ok (or not).

I mean; yes that example is UB, but the result is also clearly batshit
insane.