| commit | 785bdd9fa781f3e55c77d6f294a6c02c729e49ef | [log] [tgz] |
|---|---|---|
| author | Sam Clegg <sbc@chromium.org> | Fri Jan 06 16:40:26 2023 |
| committer | GitHub <noreply@github.com> | Fri Jan 06 16:40:26 2023 |
| tree | 9cdcec3e16301d9024bf705eaa3c0ba3891db6df | |
| parent | 0d7014e1b20ead9739f1fce54b316152413601c3 [diff] |
Don't rebuilt the cache every time the config file changes. NFC (#18462) This effectively reverts #11196. It turns out this caused a lot of unnecessary rebuilding for developers without much real benefit. If we include the config hash then ever time the config file is edited (for example, to add or remove something from WASM_ENGINES or JS_ENGINES, which are only used during testing) all the libraries would then get needlessly rebuilt. Since the sanity file already includes the emscripten version and llvm version that should catch most of he cases where the libraries really do require a rebuild. Changes to the specific llvm or emscripten GIT revision do not cause the cache to get re-built even if we do include the config file hash so it isn't really providing any usefull benefit.
Main project page: https://emscripten.org
GitHub CI status: 
Chromium builder status: emscripten-releases
Emscripten compiles C and C++ to WebAssembly using LLVM and Binaryen. Emscripten output can run on the Web, in Node.js, and in wasm runtimes.
Emscripten provides Web support for popular portable APIs such as OpenGL and SDL2, allowing complex graphical native applications to be ported, such as the Unity game engine and Google Earth. It can probably port your codebase, too!
While Emscripten mostly focuses on compiling C and C++ using Clang, it can be integrated with other LLVM-using compilers (for example, Rust has Emscripten integration, with the wasm32-unknown-emscripten and asmjs-unknown-emscripten targets).
Emscripten is available under 2 licenses, the MIT license and the University of Illinois/NCSA Open Source License.
Both are permissive open source licenses, with little if any practical difference between them.
The reason for offering both is that (1) the MIT license is well-known and suitable for a compiler toolchain, while (2) LLVM‘s original license, the University of Illinois/NCSA Open Source License, was also offered to allow Emscripten’s code to be integrated upstream into LLVM. The second reason became less important after Emscripten switched to the LLVM wasm backend, at which point there isn't any code we expect to move back and forth between the projects; also, LLVM relicensed to Apache 2.0 + exceptions meanwhile. In practice you can just consider Emscripten as MIT licensed (which allows you to do pretty much anything you want with a compiler, including commercial and non-commercial use).
See LICENSE for the full content of the licenses.