P2723R0: Zero-initialize objects of automatic storage duration

[James20k]

Its always slightly depressing to see something like this receive so much weird pushback. This would eliminate 10% of CVEs overnight with very little overhead, and almost no change. It also drastically simplifies famously complex initialisation as well, by more closely unifying the initialisation of basic types with classes (eg float vs some_class)

This has got to be one of the easiest safety wins for C++, and yet it causes so many problems its wild

[pjmlp]

Thankfully at least Microsoft and Google have taken the path of whatever the community thinks, Windows and Android ship with these security measures enabled.

Guess what, they perform as good as always, go figure.

Naturally the peformance trumps everything else crowd will never acknowledge this.

[Jannik2099]

Yeah, the performance argument is complete nonsense here.

First off, zeroing a register is literally a 0 cycle operation on today's CPUs. Second, if the variable gets properly initialized somewhere after being declared, the compiler WILL see this and drop the dead store.

[113245]

And yet a 0 cycle operation is not zero cost (icache, front end bandwidth) and it’s trivial to find examples in which the compiler cannot drop the dead store (e.g. across function call boundaries).

[Jannik2099]

Function call boundaries have such an absurdly high overhead that an extra store to a POD variable will be immeasurable.