dcc3e6e1dd
This commit replaces the "fuzzer" UI, previously accessed with the `--fuzz` and `--port` flags, with a more interesting web UI which allows more interactions with the Zig build system. Most notably, it allows accessing the data emitted by a new "time report" system, which allows users to see which parts of Zig programs take the longest to compile. The option to expose the web UI is `--webui`. By default, it will listen on `[::1]` on a random port, but any IPv6 or IPv4 address can be specified with e.g. `--webui=[::1]:8000` or `--webui=127.0.0.1:8000`. The options `--fuzz` and `--time-report` both imply `--webui` if not given. Currently, `--webui` is incompatible with `--watch`; specifying both will cause `zig build` to exit with a fatal error. When the web UI is enabled, the build runner spawns the web server as soon as the configure phase completes. The frontend code consists of one HTML file, one JavaScript file, two CSS files, and a few Zig source files which are built into a WASM blob on-demand -- this is all very similar to the old fuzzer UI. Also inherited from the fuzzer UI is that the build system communicates with web clients over a WebSocket connection. When the build finishes, if `--webui` was passed (i.e. if the web server is running), the build runner does not terminate; it continues running to serve web requests, allowing interactive control of the build system. In the web interface is an overall "status" indicating whether a build is currently running, and also a list of all steps in this build. There are visual indicators (colors and spinners) for in-progress, succeeded, and failed steps. There is a "Rebuild" button which will cause the build system to reset the state of every step (note that this does not affect caching) and evaluate the step graph again. If `--time-report` is passed to `zig build`, a new section of the interface becomes visible, which associates every build step with a "time report". For most steps, this is just a simple "time taken" value. However, for `Compile` steps, the compiler communicates with the build system to provide it with much more interesting information: time taken for various pipeline phases, with a per-declaration and per-file breakdown, sorted by slowest declarations/files first. This feature is still in its early stages: the data can be a little tricky to understand, and there is no way to, for instance, sort by different properties, or filter to certain files. However, it has already given us some interesting statistics, and can be useful for spotting, for instance, particularly complex and slow compile-time logic. Additionally, if a compilation uses LLVM, its time report includes the "LLVM pass timing" information, which was previously accessible with the (now removed) `-ftime-report` compiler flag. To make time reports more useful, ZIR and compilation caches are ignored by the Zig compiler when they are enabled -- in other words, `Compile` steps *always* run, even if their result should be cached. This means that the flag can be used to analyze a project's compile time without having to repeatedly clear cache directory, for instance. However, when using `-fincremental`, updates other than the first will only show you the statistics for what changed on that particular update. Notably, this gives us a fairly nice way to see exactly which declarations were re-analyzed by an incremental update. If `--fuzz` is passed to `zig build`, another section of the web interface becomes visible, this time exposing the fuzzer. This is quite similar to the fuzzer UI this commit replaces, with only a few cosmetic tweaks. The interface is closer than before to supporting multiple fuzz steps at a time (in line with the overall strategy for this build UI, the goal will be for all of the fuzz steps to be accessible in the same interface), but still doesn't actually support it. The fuzzer UI looks quite different under the hood: as a result, various bugs are fixed, although other bugs remain. For instance, viewing the source code of any file other than the root of the main module is completely broken (as on master) due to some bogus file-to-module assignment logic in the fuzzer UI. Implementation notes: * The `lib/build-web/` directory holds the client side of the web UI. * The general server logic is in `std.Build.WebServer`. * Fuzzing-specific logic is in `std.Build.Fuzz`. * `std.Build.abi` is the new home of `std.Build.Fuzz.abi`, since it now relates to the build system web UI in general. * The build runner now has an **actual** general-purpose allocator, because thanks to `--watch` and `--webui`, the process can be arbitrarily long-lived. The gpa is `std.heap.DebugAllocator`, but the arena remains backed by `std.heap.page_allocator` for efficiency. I fixed several crashes caused by conflation of `gpa` and `arena` in the build runner and `std.Build`, but there may still be some I have missed. * The I/O logic in `std.Build.WebServer` is pretty gnarly; there are a *lot* of threads involved. I anticipate this situation improving significantly once the `std.Io` interface (with concurrency support) is introduced.
A general-purpose programming language and toolchain for maintaining robust, optimal, and reusable software.
Documentation
If you are looking at this README file in a source tree, please refer to the Release Notes, Language Reference, or Standard Library Documentation corresponding to the version of Zig that you are using by following the appropriate link on the download page.
Otherwise, you're looking at a release of Zig, so you can find the language
reference at doc/langref.html, and the standard library documentation by
running zig std, which will open a browser tab.
Installation
A Zig installation is composed of two things:
- The Zig executable
- The lib/ directory
At runtime, the executable searches up the file system for the lib/ directory, relative to itself:
- lib/
- lib/zig/
- ../lib/
- ../lib/zig/
- (and so on)
In other words, you can unpack a release of Zig anywhere, and then begin
using it immediately. There is no need to install it globally, although this
mechanism supports that use case too (i.e. /usr/bin/zig and /usr/lib/zig/).
Building from Source
Ensure you have the required dependencies:
- CMake >= 3.15
- System C/C++ Toolchain
- LLVM, Clang, LLD development libraries == 20.x
Then it is the standard CMake build process:
mkdir build
cd build
cmake ..
make install
For more options, tips, and troubleshooting, please see the Building Zig From Source page on the wiki.
Building from Source without LLVM
In this case, the only system dependency is a C compiler.
cc -o bootstrap bootstrap.c
./bootstrap
This produces a zig2 executable in the current working directory. This is a
"stage2" build of the compiler,
without LLVM extensions, and is
therefore lacking these features:
- Release mode optimizations
- aarch64 machine code backend
- @cImport
- zig translate-c
- Ability to compile assembly files
- Some ELF linking features
- Most COFF/PE linking features
- Some WebAssembly linking features
- Ability to create import libs from def files
- Ability to create static archives from object files
- Ability to compile C, C++, Objective-C, and Objective-C++ files
However, a compiler built this way does provide a C backend, which may be useful for creating system packages of Zig projects using the system C toolchain. In this case, LLVM is not needed!
Furthermore, a compiler built this way provides an LLVM backend that produces bitcode files, which may be compiled into object files via a system Clang package. This can be used to produce system packages of Zig applications without the Zig package dependency on LLVM.
Contributing
Zig is Free and Open Source Software. We welcome bug reports and patches from everyone. However, keep in mind that Zig governance is BDFN (Benevolent Dictator For Now) which means that Andrew Kelley has final say on the design and implementation of everything.
One of the best ways you can contribute to Zig is to start using it for an open-source personal project.
This leads to discovering bugs and helps flesh out use cases, which lead to further design iterations of Zig. Importantly, each issue found this way comes with real world motivations, making it straightforward to explain the reasoning behind proposals and feature requests.
You will be taken much more seriously on the issue tracker if you have a personal project that uses Zig.
The issue label Contributor Friendly exists to help you find issues that are limited in scope and/or knowledge of Zig internals.
Please note that issues labeled Proposal but do not also have the Accepted label are still under consideration, and efforts to implement such a proposal have a high risk of being wasted. If you are interested in a proposal which is still under consideration, please express your interest in the issue tracker, providing extra insights and considerations that others have not yet expressed. The most highly regarded argument in such a discussion is a real world use case.
For more tips, please see the Contributing page on the wiki.
Community
The Zig community is decentralized. Anyone is free to start and maintain their own space for Zig users to gather. There is no concept of "official" or "unofficial". Each gathering place has its own moderators and rules. Users are encouraged to be aware of the social structures of the spaces they inhabit, and work purposefully to facilitate spaces that align with their values.
Please see the Community wiki page for a public listing of social spaces.