https://michaelfairley.com/blog/i-made-a-game-in-rust/
> It consists of ~7700 lines of Rust
...
> Compile times with Rust are Not Great. This is easily my single biggest gripe about Rust right now. The build for A Snake’s Tale takes 15+ seconds, which makes iterating rather tedious. The current incremental compiler work also doesn’t seem to make the build for A Snake’s Tale’s codebase any faster.
That compile time is Not Great, but 15 seconds for 7700 lines of code isn't even close to "far worse than C++". :P If incremental compilation is showing no benefits whatsoever, then I'm guessing that time is largely attributable to linking (and I tend to doubt that 7700 lines of code is counting the basic third-party libraries that are required to create a crossplatform GUI app (but I'd love to be surprised!), which will contribute to linkage time... LLD please!).
Re:Two years of Rust
by stevedonovan on Tuesday May 16, 2017 @02:44AM
(#14347814)
For a full rebuild, that's a reasonable C++ build time for a project of this size. But full rebuilds are not representative, if the project is composed of many independent compilation units. The compilation unit in Rust is the crate, which is an exe or a library, so currently the best strategy is lots of little crates, which is not so ergonomic (heh) with Cargo.
Actually, the compiler isn't the bottleneck - most of the time is LLVM codegen. So 'cargo check' is fast - the miri MIR interpreter likewise.
Cite a source? This isn't my experience at all, Rust is still way faster at compilation than C++ on average. The advantage that C++ currently has is ccache which helps avoid needless rebuilds (which pairs well with C++'s smaller compilation units relative to Rust); building this behavior into the compiler is part of what the incremental compilation initiative is addressing.