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| Licensed under a BSD-style license <LICENSE-BSD>, Apache License, Version 2.0 |
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| |
| # Internal details |
| |
| This file documents various internal details of zerocopy and its infrastructure |
| that consumers don't need to be concerned about. It focuses on details that |
| affect multiple files, and allows each affected code location to reference this |
| document rather than requiring us to repeat the same explanation in multiple |
| locations. |
| |
| ## CI and toolchain versions |
| |
| In CI (`.github/workflows/ci.yml`), we pin to specific versions or dates of the |
| stable and nightly toolchains. The reason is twofold: First, our UI tests (see |
| `tests/trybuild.rs` and `zerocopy-derive/tests/trybuild.rs`) depend on the |
| format of rustc's error messages, and that format can change between toolchain |
| versions (we also maintain multiple copies of our UI tests - one for each |
| toolchain version pinned in CI - for this reason). Second, not all nightlies |
| have a working Miri, so we need to pin to one that does (see |
| https://rust-lang.github.io/rustup-components-history/). |
| |
| Updating the versions pinned in CI may cause the UI tests to break. In order to |
| fix UI tests after a version update, run: |
| |
| ``` |
| $ TRYBUILD=overwrite ./cargo.sh +all test |
| ``` |
| |
| ## Crate versions |
| |
| We ensure that the crate versions of zerocopy and zerocopy-derive are always the |
| same in-tree, and that zerocopy depends upon zerocopy-derive using an exact |
| version match to the current version in-tree. This has the result that, even |
| when published on crates.io, both crates effectively constitute a single atomic |
| version. So long as the code in zerocopy is compatible with the code in |
| zerocopy-derive in the same Git commit, then publishing them both is fine. This |
| frees us from the normal task of reasoning about compatibility with a range of |
| semver-compatible versions of different crates. |
