On 21/06/14 07:55 PM, Benjamin Striegel wrote: >> No one will use Rust if it's slow. If it uses checked arithmetic, it >> will be slow. There's nothing subjective about that. > > This is the only argument that matters. > > If we are slower than C++, Rust will not replace C++ and will have > failed at its goal of making the world a safer place. The world already > has a glut of safe and slow languages; if inefficiency were acceptable, > then C++ would have been replaced long ago. > > In addition, bringing up hypothetical CPU architectures with support for > checked arithmetic is not relevant. Rust is a language designed for > 2014, not for 2024. > > And if in 2024 we are all suddenly gifted with CPUs where checked > arithmetic is literally free and if this somehow causes Rust to be > "obsolete" (which seems unlikely in any case), then so be it. Rust is > not the last systems programming language that will ever be written.
Not only does the hardware have to provide it, but each OS also has to expose it in a way that Rust could use to throw an exception, unless the proposal is to simply abort on overflow. LLVM would also have to gain support for unwinding from arithmetic operations, as it can't currently do that. Even with hardware support for the operation itself, giving every integer operation a side effect would still cripple performance by wiping out optimizations.
signature.asc
Description: OpenPGP digital signature
_______________________________________________ Rust-dev mailing list [email protected] https://mail.mozilla.org/listinfo/rust-dev
