Parallel-compiler-related cleanup
Parallel-compiler-related cleanup
I carefully split changes into commits. Commit messages are self-explanatory. Squashing is not recommended.
cc "Parallel Rustc Front-end" https://github.com/rust-lang/rust/issues/113349
r? SparrowLii
``@rustbot`` label: +WG-compiler-parallel
(S)ccache can be useful for more things that just LLVM. For example, we will soon want to use it also for GCC, and theoretically also for building stage0 Rust tools.
rustfmt fails to format this match expression, because it has several
long string literals over the maximum line width. This seems to exhibit
rustfmt issues #3863 (Gives up on chains if any line is too long) and
#3156 (Fail to format match arm when other arm has long line).
Since it's inception a long time ago, the parallel compiler and its cfgs
have been a maintenance burden. This was a necessary evil the allow
iteration while not degrading performance because of synchronization
overhead.
But this time is over. Thanks to the amazing work by the parallel
working group (and the dyn sync crimes), the parallel compiler has now
been fast enough to be shipped by default in nightly for quite a while
now.
Stable and beta have still been on the serial compiler, because they
can't use `-Zthreads` anyways.
But this is quite suboptimal:
- the maintenance burden still sucks
- we're not testing the serial compiler in nightly
Because of these reasons, it's time to end it. The serial compiler has
served us well in the years since it was split from the parallel one,
but it's over now.
Let the knight slay one head of the two-headed dragon!
bootstrap: add std_features to config.example
fix: use BTreeSet for std-features; add unit tests
* fix formatting of string in front of std_features
* rename `std_features` to `std-features` in config.toml
fix: remove space before std-features in config.toml
fix: remove explicit .into_iter conversion
bootstrap: add details for rust.std-features in config.example.toml
Co-authored-by: Onur Özkan <onurozkan.dev@outlook.com>
fix: remove `Option<T>` from `rust_std_features`
fix: move default rust_std_features to config
fix: make std_features CI rustc incompatible
use `download-ci-llvm=true` in the default compiler config
1ca2708e77 made it so that the `src/llvm-project` submodule has to be checkout for `download-ci-llvm = "if-unchanged"` to know if the submodule has been changed, but that is not required, if the submodule hasn't been checkout it cannot have been modified.
~~This PR restore the previous behavior by only updating the submodule if it has already been checkout.~~
This PR makes `download-ci-llvm = true` check if CI llvm is available and make it the default for the compiler profile, as to prevent unnecessarily checking out `src/llvm-project` with `"if-unchanged"`.
r? `````@onur-ozkan`````
enable -Zrandomize-layout in debug CI builds
This builds rustc/libs/tools with `-Zrandomize-layout` on *-debug CI runners.
Only a handful of tests and asserts break with that enabled, which is promising. One test was fixable, the rest is dealt with by disabling them through new cargo features or compiletest directives.
The config.toml flag `rust.randomize-layout` defaults to false, so it has to be explicitly enabled for now.
Additionally teach compiletest to ignore tests that rely on deterministic layout.
Tests themselves aren't built with randomization but they can still observe
slight changes in std or rustc
Set LLVM_ENABLE_ZSTD alongside LLVM_ENABLE_ZLIB so that --compress-debug-sections=zstd is an option.
Use static linking to avoid a new runtime dependency. Add an llvm.libzstd bootstrap option for LLVM
with zstd. Set it off by default except for the dist builder. Handle llvm-config --system-libs output
that contains static libraries.
We were running testing on API 18, which was already out of support for
NDK 25, and some of the ancient behavior in that image was causing
trouble when developing `rustc` features (#120326).
Update to the current LTS NDK 26, and to its minimum supported API 21.
Fixes: #120567
This commit updates the support for the `wasm-component-ld` tool
from #126967 to conditionally build it rather than unconditionally
building it when LLD is enabled. This support is disabled by default and
can be enabled by one of two means:
* the `extended` field in `config.toml` which dist builders use to build
a complete set of tools for each host platform.
* a `"wasm-component-ld"` entry in the `tools` section of `config.toml`.
Neither of these are enabled by default meaning that most local builds
will likely not have this new tool built. Dist builders should still,
however, build the tool.
handle ci-rustc incompatible options during config parse
This PR ensures that `config.toml` does not use CI rustc incompatible options when CI rustc is enabled (just like [ci-llvm checks](e2cf31a614/src/bootstrap/src/core/config/config.rs (L1809-L1836))). Some options can change compiler's behavior in certain scenarios. If we don't check these incompatible options, CI runners using CI rustc might ignore options we have explicitly set. This could be dangerous as we might think a rustc test passed with option T but in fact it wasn't tested with option T.
Later in https://github.com/rust-lang/rust/pull/122709, I will disable CI rustc if any of those options were used (similar to [this approach](dd2c24aafd/src/ci/run.sh (L165-L169))). If CI runners fail because of these checks, it means the logic in run.sh isn't covering the incompatible options correctly (since any incompatible option should turn off CI rustc).
The list may not be complete, but should be a good first step as it's better than nothing!
Blocker for https://github.com/rust-lang/rust/pull/122709
