Discussion: The va_list crate in a post RFC 2137 world

[dlrobertson]

rust-lang/rust#49878 should essentially implement the same features available in this crate. This could probably be documented somewhere in this crates documentation? That being said, I think that after rust-lang/rust#49878 is merged and even after RFC 2137 is fully implemented, this crate is still valuable for the following cases.

• core::ffi::VaList will only be available in nightly with the c_variadic feature. Crates that need to compile on stable will still need this crate.
• This code has been well tested, while rust-lang/rust#49878 is still highly experimental.
• There may be new operating systems or architectures that are not supported in rustc, that could be easily added here, but may not make sense to add to libcore.

[thepowersgang]

This crate should still stay useful for people stuck on older rust versions, but once the builtin version is available I'd suggest using that over this crate if possible (as that'd support new platforms for free)