Auto merge of #35300 - eddyb:mir-neg-overflow, r=arielb1

rustc_trans: don't Assert(Overflow(Neg)) when overflow checks are off.

Generic functions using `Neg` on primitive types would panic even in release mode, with MIR trans.
The solution is a bit hacky, as I'm checking the message, since there's no dedicated `CheckedUnOp`.

Blocks Servo rustup ([failure #1](http://build.servo.org/builders/linux-rel/builds/2477/steps/test_3/logs/stdio), [failure #2](http://build.servo.org/builders/mac-rel-css/builds/2364/steps/test/logs/stdio)) - this should be the last hurdle, it affects only one test.
tree: 405df1f63b219cdb7015409e4ce26bab3e764404
  1. man/
  2. mk/
  3. src/
  4. .gitattributes
  5. .gitignore
  6. .gitmodules
  7. .mailmap
  8. .travis.yml
  9. COMPILER_TESTS.md
  10. configure
  11. CONTRIBUTING.md
  12. COPYRIGHT
  13. LICENSE-APACHE
  14. LICENSE-MIT
  15. Makefile.in
  16. README.md
  17. RELEASES.md
README.md

The Rust Programming Language

This is the main source code repository for Rust. It contains the compiler, standard library, and documentation.

Quick Start

Read “Installing Rust” from The Book.

Building from Source

  1. Make sure you have installed the dependencies:

    • g++ 4.7 or later or clang++ 3.x
    • python 2.7 (but not 3.x)
    • GNU make 3.81 or later
    • cmake 2.8.8 or later
    • curl
    • git
  2. Clone the source with git:

    $ git clone https://github.com/rust-lang/rust.git
    $ cd rust
    
  1. Build and install:

    $ ./configure
    $ make && make install
    

    Note: You may need to use sudo make install if you do not normally have permission to modify the destination directory. The install locations can be adjusted by passing a --prefix argument to configure. Various other options are also supported – pass --help for more information on them.

    When complete, make install will place several programs into /usr/local/bin: rustc, the Rust compiler, and rustdoc, the API-documentation tool. This install does not include Cargo, Rust's package manager, which you may also want to build.

Building on Windows

There are two prominent ABIs in use on Windows: the native (MSVC) ABI used by Visual Studio, and the GNU ABI used by the GCC toolchain. Which version of Rust you need depends largely on what C/C++ libraries you want to interoperate with: for interop with software produced by Visual Studio use the MSVC build of Rust; for interop with GNU software built using the MinGW/MSYS2 toolchain use the GNU build.

MinGW

MSYS2 can be used to easily build Rust on Windows:

  1. Grab the latest MSYS2 installer and go through the installer.

  2. Run mingw32_shell.bat or mingw64_shell.bat from wherever you installed MSYS2 (i.e. C:\msys64), depending on whether you want 32-bit or 64-bit Rust. (As of the latest version of MSYS2 you have to run msys2_shell.cmd -mingw32 or msys2_shell.cmd -mingw64 from the command line instead)

  3. From this terminal, install the required tools:

    # Update package mirrors (may be needed if you have a fresh install of MSYS2)
    $ pacman -Sy pacman-mirrors
    
    # Install build tools needed for Rust. If you're building a 32-bit compiler,
    # then replace "x86_64" below with "i686". If you've already got git, python,
    # or CMake installed and in PATH you can remove them from this list. Note
    # that it is important that the `python2` and `cmake` packages **not** used.
    # The build has historically been known to fail with these packages.
    $ pacman -S git \
                make \
                diffutils \
                mingw-w64-x86_64-python2 \
                mingw-w64-x86_64-cmake \
                mingw-w64-x86_64-gcc
    
  4. Navigate to Rust's source code (or clone it), then configure and build it:

    $ ./configure
    $ make && make install
    

MSVC

MSVC builds of Rust additionally require an installation of Visual Studio 2013 (or later) so rustc can use its linker. Make sure to check the “C++ tools” option.

With these dependencies installed, the build takes two steps:

$ ./configure
$ make && make install

MSVC with rustbuild

The old build system, based on makefiles, is currently being rewritten into a Rust-based build system called rustbuild. This can be used to bootstrap the compiler on MSVC without needing to install MSYS or MinGW. All you need are Python 2, CMake, and Git in your PATH (make sure you do not use the ones from MSYS if you have it installed). You'll also need Visual Studio 2013 or newer with the C++ tools. Then all you need to do is to kick off rustbuild.

python .\src\bootstrap\bootstrap.py

Currently rustbuild only works with some known versions of Visual Studio. If you have a more recent version installed that a part of rustbuild doesn't understand then you may need to force rustbuild to use an older version. This can be done by manually calling the appropriate vcvars file before running the bootstrap.

CALL "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\bin\amd64\vcvars64.bat"
python .\src\bootstrap\bootstrap.py

Building Documentation

If you’d like to build the documentation, it’s almost the same:

$ ./configure
$ make docs

Building the documentation requires building the compiler, so the above details will apply. Once you have the compiler built, you can

$ make docs NO_REBUILD=1

To make sure you don’t re-build the compiler because you made a change to some documentation.

The generated documentation will appear in a top-level doc directory, created by the make rule.

Notes

Since the Rust compiler is written in Rust, it must be built by a precompiled “snapshot” version of itself (made in an earlier state of development). As such, source builds require a connection to the Internet, to fetch snapshots, and an OS that can execute the available snapshot binaries.

Snapshot binaries are currently built and tested on several platforms:

Platform \ Architecturex86x86_64
Windows (7, 8, Server 2008 R2)
Linux (2.6.18 or later)
OSX (10.7 Lion or later)

You may find that other platforms work, but these are our officially supported build environments that are most likely to work.

Rust currently needs between 600MiB and 1.5GiB to build, depending on platform. If it hits swap, it will take a very long time to build.

There is more advice about hacking on Rust in CONTRIBUTING.md.

Getting Help

The Rust community congregates in a few places:

Contributing

To contribute to Rust, please see CONTRIBUTING.

Rust has an IRC culture and most real-time collaboration happens in a variety of channels on Mozilla's IRC network, irc.mozilla.org. The most popular channel is #rust, a venue for general discussion about Rust. And a good place to ask for help would be #rust-beginners.

License

Rust is primarily distributed under the terms of both the MIT license and the Apache License (Version 2.0), with portions covered by various BSD-like licenses.

See LICENSE-APACHE, LICENSE-MIT, and COPYRIGHT for details.