rust/src/libpanic_unwind, branch 1.27.2

std: Minimize size of panicking on wasm

2018-04-13T14:03:00+00:00

This commit applies a few code size optimizations for the wasm target to the standard library, namely around panics. We notably know that in most configurations it's impossible for us to print anything in wasm32-unknown-unknown so we can skip larger portions of panicking that are otherwise simply informative. This allows us to get quite a nice size reduction. Finally we can also tweak where the allocation happens for the `Box` that we panic with. By only allocating once unwinding starts we can reduce the size of a panicking wasm module from 44k to 350 bytes.

Move deny(warnings) into rustbuild

2018-04-08T22:59:14+00:00

This permits easier iteration without having to worry about warnings being denied. Fixes #49517

Auto merge of #49661 - alexcrichton:bump-bootstrap, r=nikomatsakis

2018-04-07T11:58:38+00:00

Bump the bootstrap compiler to 1.26.0 beta Holy cow that's a lot of `cfg(stage0)` removed and a lot of new stable language features!

Inject the `compiler_builtins` crate whenever the `core` crate is injected

2018-04-07T07:24:35+00:00

Bump the bootstrap compiler to 1.26.0 beta

2018-04-05T14:13:45+00:00

Holy cow that's a lot of `cfg(stage0)` removed and a lot of new stable language features!

make `#[unwind]` attribute specify expectations more clearly

2018-02-21T00:12:52+00:00

You can now choose between the following: - `#[unwind(allowed)]` - `#[unwind(aborts)]` Per rust-lang/rust#48251, the default is `#[unwind(allowed)]`, though I think we should change this eventually.

Make libpanic_unwind build on CloudABI.

2018-01-04T16:55:44+00:00

CloudABI uses LLVM's libunwind for stack unwinding. There was a small bug that went by unnoticed, namely that it was not built with -fno-rtti. This caused it to (indirectly) depend on the entire C++ runtime. Now that that issue has been resolved, it is also perfectly fine to make use of this library for programming languages other than C++.

std: Add a new wasm32-unknown-unknown target

2017-11-20T05:07:41+00:00

This commit adds a new target to the compiler: wasm32-unknown-unknown. This target is a reimagining of what it looks like to generate WebAssembly code from Rust. Instead of using Emscripten which can bring with it a weighty runtime this instead is a target which uses only the LLVM backend for WebAssembly and a "custom linker" for now which will hopefully one day be direct calls to lld. Notable features of this target include: * There is zero runtime footprint. The target assumes nothing exists other than the wasm32 instruction set. * There is zero toolchain footprint beyond adding the target. No custom linker is needed, rustc contains everything. * Very small wasm modules can be generated directly from Rust code using this target. * Most of the standard library is stubbed out to return an error, but anything related to allocation works (aka `HashMap`, `Vec`, etc). * Naturally, any `#[no_std]` crate should be 100% compatible with this new target. This target is currently somewhat janky due to how linking works. The "linking" is currently unconditional whole program LTO (aka LLVM is being used as a linker). Naturally that means compiling programs is pretty slow! Eventually though this target should have a linker. This target is also intended to be quite experimental. I'm hoping that this can act as a catalyst for further experimentation in Rust with WebAssembly. Breaking changes are very likely to land to this target, so it's not recommended to rely on it in any critical capacity yet. We'll let you know when it's "production ready". --- Currently testing-wise this target is looking pretty good but isn't complete. I've got almost the entire `run-pass` test suite working with this target (lots of tests ignored, but many passing as well). The `core` test suite is still getting LLVM bugs fixed to get that working and will take some time. Relatively simple programs all seem to work though! --- It's worth nothing that you may not immediately see the "smallest possible wasm module" for the input you feed to rustc. For various reasons it's very difficult to get rid of the final "bloat" in vanilla rustc (again, a real linker should fix all this). For now what you'll have to do is: cargo install --git https://github.com/alexcrichton/wasm-gc wasm-gc foo.wasm bar.wasm And then `bar.wasm` should be the smallest we can get it! --- In any case for now I'd love feedback on this, particularly on the various integration points if you've got better ideas of how to approach them!

Add missing dependency for Windows

2017-08-27T10:02:24+00:00

*: remove crate_{name,type} attributes

2017-08-25T20:18:21+00:00

Fixes #41701.