3 ms·

I thought that rustc was boostrapped from the old c based compiler(allowing you to build clean from source) multiple times(C -> Rust 0.x? -> Rust 1.0)? From wh

I thought that rustc was boostrapped from the old c based compiler(allowing you to build clean from source) multiple times(C -> Rust 0.x? -> Rust 1.0)? From what I last saw of cargo there's not a clean path that lets you build from source that doesn't involve pulling binaries(and is really painful if you want to use cargo on a non-binary platform like RPi.

Gankro 11y ago
There's never been a C-based compiler. Rust started out as OCaml. A true bootstrap would take weeks of non-stop compiling. You'd end up compiling rustc itself about 900 times, ignoring all the different LLVM builds, I think. Rust bootstraps from a binary snapshot of itself, and so you would have to work through the list of every snapshot ever (about 300, but you need to build rustc 3 times for each snapshot to properly bootstrap that copy). The snapshots are listed here: https://github.com/rust-lang/rust/blob/master/src/snapshots.txt https://github.com/rust-lang/rust/blob/master/src/snapshots.... In the past the snapshots were taken almost weekly as massive language churn dictated. Now they're quite rare.
steveklabnik 11y ago
The situation with Cargo would be exactly the same: before Cargo existed, it couldn't use Cargo, because Cargo didn't exist. You can boostrap your own Cargo from that time period if you'd like, but that doesn't mean it's easy. But it's no different than rustc; where you can bootstrap your own snapshots from the OCaml compiler.
throwaway999888 11y ago
> I thought that rustc was boostrapped from the old c based compiler(allowing you to build clean from source) What's with all the baseless assumptions of the initial Rust compiler being written in either C or C++ in this thread? Contrary to apparently popular belief, C and C++ aren't some primordial lifeform compiler language which all language implementations have to be initially written in. Believe it or not, you can write a compiler in any (general purpose) programming language! Amazing, I know.

Gankro 11y ago

There's never been a C-based compiler. Rust started out as OCaml. A true bootstrap would take weeks of non-stop compiling. You'd end up compiling rustc itself about 900 times, ignoring all the different LLVM builds, I think. Rust bootstraps from a binary snapshot of itself, and so you would have to work through the list of every snapshot ever (about 300, but you need to build rustc 3 times for each snapshot to properly bootstrap that copy). The snapshots are listed here: https://github.com/rust-lang/rust/blob/master/src/snapshots.txt https://github.com/rust-lang/rust/blob/master/src/snapshots.... In the past the snapshots were taken almost weekly as massive language churn dictated. Now they're quite rare.

steveklabnik 11y ago

The situation with Cargo would be exactly the same: before Cargo existed, it couldn't use Cargo, because Cargo didn't exist. You can boostrap your own Cargo from that time period if you'd like, but that doesn't mean it's easy. But it's no different than rustc; where you can bootstrap your own snapshots from the OCaml compiler.

throwaway999888 11y ago

> I thought that rustc was boostrapped from the old c based compiler(allowing you to build clean from source) What's with all the baseless assumptions of the initial Rust compiler being written in either C or C++ in this thread? Contrary to apparently popular belief, C and C++ aren't some primordial lifeform compiler language which all language implementations have to be initially written in. Believe it or not, you can write a compiler in any (general purpose) programming language! Amazing, I know.