README.md

   1 # The Rust Programming Language
   2
   3 This is the main source code repository for [Rust]. It contains the compiler,
   4 standard library, and documentation.
   5
   6 [Rust]: https://www.rust-lang.org/
   7
   8 **Note: this README is for _users_ rather than _contributors_.**
   9 If you wish to _contribute_ to the compiler, you should read
  10 [CONTRIBUTING.md](CONTRIBUTING.md) instead.
  11
  12 ## Quick Start
  13
  14 Read ["Installation"] from [The Book].
  15
  16 ["Installation"]: https://doc.rust-lang.org/book/ch01-01-installation.html
  17 [The Book]: https://doc.rust-lang.org/book/index.html
  18
  19 ## Installing from Source
  20
  21 The Rust build system uses a Python script called `x.py` to build the compiler,
  22 which manages the bootstrapping process. It lives at the root of the project.
  23
  24 The `x.py` command can be run directly on most Unix systems in the following
  25 format:
  26
  27 ```sh
  28 ./x.py <subcommand> [flags]
  29 ```
  30
  31 This is how the documentation and examples assume you are running `x.py`.
  32 Some alternative ways are:
  33
  34 ```sh
  35 # On a Unix shell if you don't have the necessary `python3` command
  36 ./x <subcommand> [flags]
  37
  38 # On the Windows Command Prompt (if .py files are configured to run Python)
  39 x.py <subcommand> [flags]
  40
  41 # You can also run Python yourself, e.g.:
  42 python x.py <subcommand> [flags]
  43 ```
  44
  45 More information about `x.py` can be found by running it with the `--help` flag
  46 or reading the [rustc dev guide][rustcguidebuild].
  47
  48 [gettingstarted]: https://rustc-dev-guide.rust-lang.org/getting-started.html
  49 [rustcguidebuild]: https://rustc-dev-guide.rust-lang.org/building/how-to-build-and-run.html
  50
  51 ### Dependencies
  52
  53 Make sure you have installed the dependencies:
  54
  55 * `python` 3 or 2.7
  56 * `git`
  57 * A C compiler (when building for the host, `cc` is enough; cross-compiling may
  58   need additional compilers)
  59 * `curl` (not needed on Windows)
  60 * `pkg-config` if you are compiling on Linux and targeting Linux
  61 * `libiconv` (already included with glibc on Debian-based distros)
  62
  63 To build Cargo, you'll also need OpenSSL (`libssl-dev` or `openssl-devel` on
  64 most Unix distros).
  65
  66 If building LLVM from source, you'll need additional tools:
  67
  68 * `g++`, `clang++`, or MSVC with versions listed on
  69   [LLVM's documentation](https://llvm.org/docs/GettingStarted.html#host-c-toolchain-both-compiler-and-standard-library)
  70 * `ninja`, or GNU `make` 3.81 or later (Ninja is recommended, especially on
  71   Windows)
  72 * `cmake` 3.13.4 or later
  73 * `libstdc++-static` may be required on some Linux distributions such as Fedora
  74   and Ubuntu
  75
  76 On tier 1 or tier 2 with host tools platforms, you can also choose to download
  77 LLVM by setting `llvm.download-ci-llvm = true`.
  78 Otherwise, you'll need LLVM installed and `llvm-config` in your path.
  79 See [the rustc-dev-guide for more info][sysllvm].
  80
  81 [sysllvm]: https://rustc-dev-guide.rust-lang.org/building/new-target.html#using-pre-built-llvm
  82
  83
  84 ### Building on a Unix-like system
  85
  86 1. Clone the [source] with `git`:
  87
  88    ```sh
  89    git clone https://github.com/rust-lang/rust.git
  90    cd rust
  91    ```
  92
  93 [source]: https://github.com/rust-lang/rust
  94
  95 2. Configure the build settings:
  96
  97    The Rust build system uses a file named `config.toml` in the root of the
  98    source tree to determine various configuration settings for the build.
  99    Set up the defaults intended for distros to get started. You can see a full
 100    list of options in `config.toml.example`.
 101
 102    ```sh
 103    printf 'profile = "user" \nchangelog-seen = 2 \n' > config.toml
 104    ```
 105
 106    If you plan to use `x.py install` to create an installation, it is
 107    recommended that you set the `prefix` value in the `[install]` section to a
 108    directory.
 109
 110 3. Build and install:
 111
 112    ```sh
 113    ./x.py build && ./x.py install
 114    ```
 115
 116    When complete, `./x.py install` will place several programs into
 117    `$PREFIX/bin`: `rustc`, the Rust compiler, and `rustdoc`, the
 118    API-documentation tool. If you've set `profile = "user"` or
 119    `build.extended = true`, it will also include [Cargo], Rust's package
 120    manager.
 121
 122 [Cargo]: https://github.com/rust-lang/cargo
 123
 124 ### Building on Windows
 125
 126 On Windows, we suggest using [winget] to install dependencies by running the
 127 following in a terminal:
 128
 129 ```powershell
 130 winget install -e Python.Python.3
 131 winget install -e Kitware.CMake
 132 winget install -e Git.Git
 133 ```
 134
 135 Then edit your system's `PATH` variable and add: `C:\Program Files\CMake\bin`.
 136 See
 137 [this guide on editing the system `PATH`](https://www.java.com/en/download/help/path.html)
 138 from the Java documentation.
 139
 140 [winget]: https://github.com/microsoft/winget-cli
 141
 142 There are two prominent ABIs in use on Windows: the native (MSVC) ABI used by
 143 Visual Studio and the GNU ABI used by the GCC toolchain. Which version of Rust
 144 you need depends largely on what C/C++ libraries you want to interoperate with.
 145 Use the MSVC build of Rust to interop with software produced by Visual Studio
 146 and the GNU build to interop with GNU software built using the MinGW/MSYS2
 147 toolchain.
 148
 149 #### MinGW
 150
 151 [MSYS2][msys2] can be used to easily build Rust on Windows:
 152
 153 [msys2]: https://www.msys2.org/
 154
 155 1. Download the latest [MSYS2 installer][msys2] and go through the installer.
 156
 157 2. Run `mingw32_shell.bat` or `mingw64_shell.bat` from the MSYS2 installation
 158    directory (e.g. `C:\msys64`), depending on whether you want 32-bit or 64-bit
 159    Rust. (As of the latest version of MSYS2 you have to run `msys2_shell.cmd
 160    -mingw32` or `msys2_shell.cmd -mingw64` from the command line instead.)
 161
 162 3. From this terminal, install the required tools:
 163
 164    ```sh
 165    # Update package mirrors (may be needed if you have a fresh install of MSYS2)
 166    pacman -Sy pacman-mirrors
 167
 168    # Install build tools needed for Rust. If you're building a 32-bit compiler,
 169    # then replace "x86_64" below with "i686". If you've already got Git, Python,
 170    # or CMake installed and in PATH you can remove them from this list.
 171    # Note that it is important that you do **not** use the 'python2', 'cmake',
 172    # and 'ninja' packages from the 'msys2' subsystem.
 173    # The build has historically been known to fail with these packages.
 174    pacman -S git \
 175                make \
 176                diffutils \
 177                tar \
 178                mingw-w64-x86_64-python \
 179                mingw-w64-x86_64-cmake \
 180                mingw-w64-x86_64-gcc \
 181                mingw-w64-x86_64-ninja
 182    ```
 183
 184 4. Navigate to Rust's source code (or clone it), then build it:
 185
 186    ```sh
 187    ./x.py build && ./x.py install
 188    ```
 189
 190 #### MSVC
 191
 192 MSVC builds of Rust additionally require an installation of Visual Studio 2017
 193 (or later) so `rustc` can use its linker.  The simplest way is to get
 194 [Visual Studio], check the "C++ build tools" and "Windows 10 SDK" workload.
 195
 196 [Visual Studio]: https://visualstudio.microsoft.com/downloads/
 197
 198 (If you're installing CMake yourself, be careful that "C++ CMake tools for
 199 Windows" doesn't get included under "Individual components".)
 200
 201 With these dependencies installed, you can build the compiler in a `cmd.exe`
 202 shell with:
 203
 204 ```sh
 205 python x.py build
 206 ```
 207
 208 Right now, building Rust only works with some known versions of Visual Studio.
 209 If you have a more recent version installed and the build system doesn't
 210 understand, you may need to force rustbuild to use an older version.
 211 This can be done by manually calling the appropriate vcvars file before running
 212 the bootstrap.
 213
 214 ```batch
 215 CALL "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat"
 216 python x.py build
 217 ```
 218
 219 #### Specifying an ABI
 220
 221 Each specific ABI can also be used from either environment (for example, using
 222 the GNU ABI in PowerShell) by using an explicit build triple. The available
 223 Windows build triples are:
 224 - GNU ABI (using GCC)
 225     - `i686-pc-windows-gnu`
 226     - `x86_64-pc-windows-gnu`
 227 - The MSVC ABI
 228     - `i686-pc-windows-msvc`
 229     - `x86_64-pc-windows-msvc`
 230
 231 The build triple can be specified by either specifying `--build=<triple>` when
 232 invoking `x.py` commands, or by creating a `config.toml` file (as described in
 233 [Installing from Source](#installing-from-source)), and modifying the `build`
 234 option under the `[build]` section.
 235
 236 ### Configure and Make
 237
 238 While it's not the recommended build system, this project also provides a
 239 configure script and makefile (the latter of which just invokes `x.py`).
 240
 241 ```sh
 242 ./configure
 243 make && sudo make install
 244 ```
 245
 246 `configure` generates a `config.toml` which can also be used with normal `x.py`
 247 invocations.
 248
 249 ## Building Documentation
 250
 251 If you'd like to build the documentation, it's almost the same:
 252
 253 ```sh
 254 ./x.py doc
 255 ```
 256
 257 The generated documentation will appear under `doc` in the `build` directory for
 258 the ABI used. That is, if the ABI was `x86_64-pc-windows-msvc`, the directory
 259 will be `build\x86_64-pc-windows-msvc\doc`.
 260
 261 ## Notes
 262
 263 Since the Rust compiler is written in Rust, it must be built by a precompiled
 264 "snapshot" version of itself (made in an earlier stage of development).
 265 As such, source builds require an Internet connection to fetch snapshots, and an
 266 OS that can execute the available snapshot binaries.
 267
 268 See https://doc.rust-lang.org/nightly/rustc/platform-support.html for a list of
 269 supported platforms.
 270 Only "host tools" platforms have a pre-compiled snapshot binary available; to
 271 compile for a platform without host tools you must cross-compile.
 272
 273 You may find that other platforms work, but these are our officially supported
 274 build environments that are most likely to work.
 275
 276 ## Getting Help
 277
 278 See https://www.rust-lang.org/community for a list of chat platforms and forums.
 279
 280 ## Contributing
 281
 282 See [CONTRIBUTING.md](CONTRIBUTING.md).
 283
 284 ## License
 285
 286 Rust is primarily distributed under the terms of both the MIT license and the
 287 Apache License (Version 2.0), with portions covered by various BSD-like
 288 licenses.
 289
 290 See [LICENSE-APACHE](LICENSE-APACHE), [LICENSE-MIT](LICENSE-MIT), and
 291 [COPYRIGHT](COPYRIGHT) for details.
 292
 293 ## Trademark
 294
 295 [The Rust Foundation][rust-foundation] owns and protects the Rust and Cargo
 296 trademarks and logos (the "Rust Trademarks").
 297
 298 If you want to use these names or brands, please read the
 299 [media guide][media-guide].
 300
 301 Third-party logos may be subject to third-party copyrights and trademarks. See
 302 [Licenses][policies-licenses] for details.
 303
 304 [rust-foundation]: https://foundation.rust-lang.org/
 305 [media-guide]: https://foundation.rust-lang.org/policies/logo-policy-and-media-guide/
 306 [policies-licenses]: https://www.rust-lang.org/policies/licenses