@seanbax The work you are doing is great for the future of C++ even if the form ends up committeed into ugliness. Did I understand correctly the Itanium ABI on x86_64 is used by circle? Is there a write up on the rationale/pros/cons? When are you next due to live cast an interview?

@DarrylMiles The whole linux ecosystem uses itanium abi. Crucial to support it.

@seanbax are we matching freak with rust? they got unsafe blocks, now we have safe blocks?

@is_losy That's the gist of it.

@seanbax Sean I noticed for the safe context you say “the following make the program ill-formed” but you also list that each unsafe action is “undefined behavior” I thought a program was either ill-formed or UB? Can it be both?

@static_assert_0 It's ill-formed in the safe context. In the unsafe context it could raise UB. The unsafe context is all existing C++ code. It's full of operations that can't be checked for soundness.

@seanbax Awesome! How does it compare to cpp2

@motonarola Cpp2 isn't memory safe.

@seanbax Why prescribe panic on out of bounds for builtin types etc, instead of making it an implementation-defined choice of exception or panic? For testing & debugging I’d probably want to have exceptions thrown. Or maybe my safety requirements preclude me from abrupt termination

@GpMueller Went back and forth but didn't want to put conditional noexcept-specifiers on the accessors and everything downstream of those. That just makes a mess.

@seanbax I feel too much borrowed from Rust :)) I like how Rust's default behavior is to move values, I wish C++ had that

@Saamur_ai Why is it too much borrowed from Rust? Rust solves the safety problem.

@seanbax were you surprised by the poll results you mention at the end? “We should promise more committee time on borrow checking?” — SF: 20, WF: 7, N: 1, WA: 0, SA: 0

@nikc_12 Hard to say what the poll means. Somewhat should ask the direction group what the safety strategy is.

@seanbax Congratulations!

@seanbax Nice 😎

@seanbax i gotchu fam

@seanbax Your work ethic is impressive. 💪

@seanbax Recently I've been thinking "where have Sean Baxter's c++ Twitter updates gone? Hope he's ok. " I know see you've been hard at work. Thank you!

@seanbax Simply amazing stuff @seanbax! Congrats!

@seanbax Congrats, its a huge milestone 🥳

@seanbax It looks great, looking forward how it goes.

@seanbax Good luck with the standards process! Reading @__phantomderp makes me think the process is… challenging 😥

@seanbax I love to be able to restrict my code with "feature on safety". However, I'm worried that it will take forever to agree on what "safety" should be. I think it would be beneficial to have a version number, allowing us to get started sooner.

@seanbax @MichaelShah Thanks

@seanbax boring... just use Rust

@seanbax Nice work! Hope not to many complains. The only thing that's a bit confusing is that the examples are made in circle which might be miss leading otherwise great

@seanbax A link to 2024-09 WG mailing is still not available at

@seanbax Can you please generate a version with a Sans Serif font? Asking for a friend.