Comment by gpderetta
2 days ago
I litterally have no idea what are you trying to say. Do you mean that bar should be allowed to access *ptr with impunity or not?
2 days ago
I litterally have no idea what are you trying to say. Do you mean that bar should be allowed to access *ptr with impunity or not?
I'm not trying to say anything. I said and meant exactly what I said. No more, no less. Your logic is obviously flawed. There is nothing preventing that optimization in the presence of a forged pointer in bar().
Either there is no provenance, forging is allowed and the optimization is disallowed; or there is provenance and forging the pointer and attempting to inspect (or modify) the value of *ptr in bar() is UB.
You never converted ptr to an integer. If you did, if the pointer escapes, yes, I claim that then the allocation can't be optimized away. Why is that so bad?
Attempting to inspect or modify the value of *ptr in bar() through a forged pointer was always UB. You are saying absolutely nothing meaningful.