befd1eb4ec
Generalize LLD usage in bootstrap The current usage of using LLD (`rust.use-lld = true`) in bootstrap is a bit messy. What it claimed: > Indicates whether LLD will be used to link Rust crates during bootstrap on > supported platforms. The LLD from the bootstrap distribution will be used > and not the LLD compiled during the bootstrap. What it did: 1) On MSVC, it did indeed use the snapshot compiler's `rust-lld`, but at the same time it was invoking a global `lld` binary (since https://github.com/rust-lang/rust/pull/102101), therefore it wouldn't work if `lld` wasn't available. 2) On other targets, it was just straight up using a global `lld` linker. If it wasn't available, it would fail. This PR (hopefully) cleans up handling of LLD in bootstrap. It introduces a new enum called `LldMode`, which explicitly distinguishes between no LLD, external LLD and self-contained LLD. Since it's non-trivial to provide a custom path to LLD, if an external `lld` is used, the linker binary has to be named exactly `lld` and it has to be available in PATH. In addition, this PR also dog-foods [MCP510](https://github.com/rust-lang/compiler-team/issues/510) in bootstrap. To keep backwards compatibility somewhat, I kept the original `use-lld` flag and mapped the `true` value to `"external"`, which is how it behaved before on Linux and other non-MSVC targets. Having the option to use an external `lld` on Linux should come in handy for testing on CI once MCP510 sets the default linker on Linux to `lld`. Note that thanks to MCP510, currently "self-contained" means that `lld` is used from the stage N-1 compiler (before, we always used `lld` from the snapshot/stage0 compiler). Best reviewed commit by commit. CC `@petrochenkov` |
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| .. | ||
| bootstrap | ||
| ci | ||
| doc | ||
| etc | ||
| librustdoc | ||
| llvm-project@7738295178 | ||
| rustdoc-json-types | ||
| tools | ||
| README.md | ||
| stage0.json | ||
| version | ||
This directory contains some source code for the Rust project, including:
- The bootstrapping build system
- Various submodules for tools, like cargo, tidy, etc.
For more information on how various parts of the compiler work, see the rustc dev guide.