this also fixes a bug where bootstrap would try to use the fake `rustc` binary built by bootstrap -
cargo puts it in a different directory when using `cargo run` instead of x.py
The majority of the code is only used by either rustbuild or
rustc_llvm's build script. Rust_build is compiled once for rustbuild and
once for every stage. This means that the majority of the code in this
crate is needlessly compiled multiple times. By moving only the code
actually used by the respective crates to rustbuild and rustc_llvm's
build script, this needless duplicate compilation is avoided.
First, this reverts the `CFLAGS`/`CXXFLAGS` of #93918. Those flags are
already read by `cc` and populated into `Build` earlier on in the
process. We shouldn't be overriding that based on `CFLAGS`, since `cc`
also respects overrides like `CFLAGS_{TARGET}` and `HOST_CFLAGS`, which
we want to take into account.
Second, this adds the same capability to specify target-specific
versions of `LDFLAGS` as we have through `cc` for the `C*` flags:
https://github.com/alexcrichton/cc-rs#external-configuration-via-environment-variables
Note that this also necessitated an update to compiletest to treat
CXXFLAGS separately from CFLAGS.
build: dist: defer PlainSourceTarball
Apparently it changes some tool sources and invalidates their fingerprints, forcing us to build them several times (before and after vendoring sources).
I have not dug into why vendoring actually invalidates the figreprints, but moving the vendoring lower in the pipeline seems to avoid the issue.
I could imagine that we somehow write a .cargo/config somewhere which somehow makes subsequent builds use the vendored deps but I was not able to find anything.
I checked the sizes of generated archives pre and post patch and their are the same, so I hope there is no functional change.
Fixes#93033
x.py has support for excluding some steps from the invocation, but
unfortunately that's not granular enough: some steps have the same name
in different modules, and that prevents excluding only *some* of them.
As a practical example, let's say you need to run everything in `./x.py
test` except for the standard library tests, as those tests require IPv6
and need to be executed on a separate machine. Before this commit, if
you were to just run this:
./x.py test --exclude library/std
...the execution would fail, as that would not only exclude running the
tests for the standard library, it would also exclude generating its
documentation (breaking linkchecker).
This commit adds support for an optional module annotation in --exclude
paths, allowing the user to choose which module to exclude from:
./x.py test --exclude test::library/std
This maintains backward compatibility, but also allows for more ganular
exclusion. More examples on how this works:
| `--exclude` | Docs | Tests |
| ------------------- | ------- | ------- |
| `library/std` | Skipped | Skipped |
| `doc::library/std` | Skipped | Run |
| `test::library/std` | Run | Skipped |
Note that the new behavior only works in the `--exclude` flag, and not
in other x.py arguments or flags yet.
Apparently it changes some tool sources and invalidates their fingerprints, forcing us to build them several times (before and after vendoring sources).
I have not dug into why vendoring actually invalidates the figreprints, but the moving the vendoring lower in the pipeline seems to avoid the issue.
I could imagine that we somehow write a .cargo/config somewhere which somehow makes subsequent builds use the vendored deps but I was not able to find anything.
I checked the sizes of generated archives pre and post patch and their are the same, so I hope there is not functional change.
Fixes#93033
DF_ORIGIN flag signifies that the object being loaded may make reference to the $ORIGIN substitution string.
Some implementations are just ignoring DF_ORIGIN and do substitution for $ORIGIN if present (whatever DF_ORIGIN pr
Set the flag inconditionally if rpath is wanted.
Currently the verbosity settings are:
- 2: RUSTC-SHIM envvars get spammed on every invocation, O(30) lines
cargo is passed -v which outputs CLI invocations, O(5) lines
- 3: cargo is passed -vv which outputs build script output, O(0-10) lines
This commit changes it to:
- 1: cargo is passed -v, O(5) lines
- 2: cargo is passed -vv, O(10) lines
- 3: RUSTC-SHIM envvars get spammed, O(30) lines
Assemble the compiler when running `x.py build`
Previously, there was no way to actually get binaries in
`build/$TARGET/stage1/bin` without building the standard library. This
makes it possible to build just the compiler. This can be useful when
the standard library isn't actually necessary for trying out your tests
(e.g. a bug that can be reproduced with only a `no_core` crate).
Closes https://github.com/rust-lang/rust/issues/73519.
Previously, there was no way to actually get binaries in
`build/$TARGET/stage1/bin` without building the standard library. This
makes it possible to build just the compiler. This can be useful when
the standard library isn't actually necessary for trying out your tests
(e.g. a bug that can be reproduced with only a `no_core` crate).
Remove hack ignoring unused attributes for stage 0 std
This seems to no longer be giving spurious errors when incremental is
enabled.
Closes https://github.com/rust-lang/rust/issues/58633.
Fix compiling other codegen backends when llvm is enabled
Extracted from #81746
Without this change rustbuild will not pass the required linker argument to find libllvm. While other backends likely don't use libllvm, it is necessary to be able to link against rustc_driver as the llvm backend is linked into it.
Now that Cargo deduplicates diagnostics from different targets, this doesn't flood the console with
duplicate errors.
Note that this doesn't add `--all-targets` in `Builder::cargo` directly because `impl Step for Std`
actually wants to omit `--all-targets` the first time while it's still building libtest.
When passed `--all-targets`, this warns that the option isn't needed, but still continues to compile.
Rollup of 7 pull requests
Successful merges:
- #85807 (bootstrap: Disable initial-exec TLS model on powerpc)
- #87761 (Fix overflow in rustc happening if the `err_count()` is reduced in a stage.)
- #87775 (Add hint for unresolved associated trait items if the trait has a single item)
- #87779 (Remove special case for statement `NodeId` assignment)
- #87787 (Use `C-unwind` ABI for `__rust_start_panic` in `panic_abort`)
- #87809 (Fix typo in the ptr documentation)
- #87816 (Sync rustc_codegen_cranelift)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
The recursion_limit attribute avoids the following error:
```
error[E0275]: overflow evaluating the requirement `std::ptr::Unique<rustc_ast::Pat>: std::marker::Send`
|
= help: consider adding a `#![recursion_limit="256"]` attribute to your crate (`rustfmt_nightly`)
```
The `RustdocGUI::should_run` condition spawns `npm list` several times
which adds up to seconds of wall-time.
Evaluate the condition lazily to to keep `./x.py test tidy` and similar
short-running tasks fast.
## User-facing changes
- Intra-doc links to primitives that currently go to rust-lang.org/nightly/std/primitive.x.html will start going to channel that rustdoc was built with. Nightly will continue going to /nightly; Beta will link to /beta; stable compilers will link to /1.52.1 (or whatever version they were built as).
- Cross-crate links from std to core currently go to /nightly unconditionally. They will start going to /1.52.0 on stable channels (but remain the same on nightly channels).
- Intra-crate links from std to std (or core to core) currently go to the same URL they are hosted at; they will continue to do so. Notably, this is different from everything else because it can preserve the distinction between /stable and /1.52.0 by using relative links.
Note that "links" includes both intra-doc links and rustdoc's own
automatically generated hyperlinks.
## Implementation changes
- Update the testsuite to allow linking to /beta and /1.52.1 in docs
- Use an html_root_url for the standard library that's dependent on the channel
This avoids linking to nightly docs on stable.
- Update rustdoc to use channel-dependent links for primitives from an
unknown crate
- Set DOC_RUST_LANG_ORG_CHANNEL from bootstrap to ensure it's in sync
- Include doc.rust-lang.org in the channel
- Add rustfmt to `x.py check`
- Update Cargo.lock
- Remove rustfmt from the toolstate list
- Make rustfmt an in-tree tool
- Give an error on `x.py test rustfmt` if rustfmt fails to build or if tests fail
- Don't call `save_toolstate` when testing rustfmt
- Add clippy_dev to the rust workspace
Before, it would give an error that it wasn't either included or
excluded from the workspace:
```
error: current package believes it's in a workspace when it's not:
current: /home/joshua/rustc/src/tools/clippy/clippy_dev/Cargo.toml
workspace: /home/joshua/rustc/Cargo.toml
this may be fixable by adding `src/tools/clippy/clippy_dev` to the `workspace.members` array of the manifest located at: /home/joshua/rustc/Cargo.toml
Alternatively, to keep it out of the workspace, add the package to the `workspace.exclude` array, or add an empty `[workspace]` table to the package's manifest.
```
- Change clippy's copy of compiletest not to special-case
rust-lang/rust. Using OUT_DIR confused `clippy_dev` and it couldn't find
the test outputs. This is one of the reasons why `cargo dev bless` used
to silently do nothing (the others were that `CARGO_TARGET_DIR` and
`PROFILE` weren't set appropriately).
- Run clippy_dev on test failure
I tested this by removing a couple lines from a stderr file, and they
were correctly replaced.
- Fix clippy_dev warnings
Adds bootstrap rules to support installing rust-demangler.
When compiling with `-Z instrument-coverage`, the coverage reports are
generated by `llvm-cov`. `llvm-cov` includes a built-in demangler for
C++, and an option to supply an alternate demangler. For Rust, we have
`rust-demangler`, currently used in `rustc` coverage tests.
Fuchsia's toolchain for Rust is built via `./x.py install`. Fuchsia is
adding support for Rust coverage, and we need to include the
`rust-demangler` in the installed `bin` directory.
Configured rust-demangler as an in-tree extended tool.
Added tests to support `./x.py test rust-demangler`.
Install with extended tools by default only if `profiler = true`.
- Rename `broken_intra_doc_links` to `rustdoc::broken_intra_doc_links`
- Ensure that the old lint names still work and give deprecation errors
- Register lints even when running doctests
Otherwise, all `rustdoc::` lints would be ignored.
- Register all existing lints as removed
This unfortunately doesn't work with `register_renamed` because tool
lints have not yet been registered when rustc is running. For similar
reasons, `check_backwards_compat` doesn't work either. Call
`register_removed` directly instead.
- Fix fallout
+ Rustdoc lints for compiler/
+ Rustdoc lints for library/
Note that this does *not* suggest `rustdoc::broken_intra_doc_links` for
`rustdoc::intra_doc_link_resolution_failure`, since there was no time
when the latter was valid.
Remove `ENABLE_DOWNLOAD_RUSTC` constant
`ENABLE_DOWNLOAD_RUSTC` was introduced as part of the MVP for `download-rustc` as a way not to rebuild artifacts that have already been downloaded. Unfortunately, it doesn't work very well:
- Steps are ignored by default, which makes it easy to leave out a step
that should be built. For example, the MVP forgot to enable any tests,
so it was only possible to *build* locally.
- It didn't work correctly even when it was enabled: calling
`builder.ensure()` would completely ignore the constant and rebuild the
step anyway. This has no obvious fix since `ensure()` has to return a
`Step::Output`.
Instead, this handles `download-rustc` in `impl Step for Rustc` and
`impl Step for Std`, which to my knowledge are the only build steps that
don't first go through `impl Step for Sysroot` (`Rustc` is used for
the `rustc-dev` component).
See https://github.com/rust-lang/rust/pull/79540#discussion_r563350075 and https://github.com/rust-lang/rust/issues/81930 for further context.
Here are some example runs with these changes and `download-rustc`
enabled:
```
$ x.py build src/tools/clippy
Building stage1 tool clippy-driver (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 1m 09s
Building stage1 tool cargo-clippy (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.11s
$ x.py test src/tools/clippy
Finished dev [unoptimized + debuginfo] target(s) in 0.09s
Building stage1 tool clippy-driver (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.09s
Building rustdoc for stage1 (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.28s
Finished release [optimized] target(s) in 15.26s
Running build/x86_64-unknown-linux-gnu/stage1-tools/x86_64-unknown-linux-gnu/release/deps/clippy_driver-8b407b140e0aa91c
test result: ok. 592 passed; 0 failed; 3 ignored; 0 measured; 0 filtered out
$ x.py build src/tools/rustdoc
Building rustdoc for stage1 (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 41.28s
Build completed successfully in 0:00:41
$ x.py test src/test/rustdoc-ui
Building stage0 tool compiletest (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.12s
Building rustdoc for stage1 (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.10s
test result: ok. 105 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 8.15s
$ x.py build compiler/rustc
Finished dev [unoptimized + debuginfo] target(s) in 0.09s
Build completed successfully in 0:00:00
```
Note a few things:
- Clippy depends on stage1 rustc-dev artifacts, but rustc didn't have to
be recompiled. Instead, the artifacts were copied automatically.
- All steps are always enabled. There is no danger of forgetting a step,
since only the entrypoints have to handle `download-rustc`.
- Building the compiler (`compiler/rustc`) automatically does no work.
Helps with https://github.com/rust-lang/rust/issues/81930.
r? `@Mark-Simulacrum`
Propagate RUSTDOCFLAGS in the environment when documenting
Previously, RUSTDOCFLAGS would get overriden when bootstrap set
`RUSTDOCFLAGS` itself. Propagate the flag manually, using the same logic
as `RUSTFLAGS`.
Fixes https://github.com/rust-lang/rust/issues/75256.
This was introduced as part of the MVP for `download-rustc`.
Unfortunately, it doesn't work very well:
- Steps are ignored by default, which makes it easy to leave out a step
that should be built. For example, the MVP forgot to enable any tests,
so it was *only* possible to build locally.
- It didn't work correctly even when it was enabled: calling
`builder.ensure()` would completely ignore the constant and rebuild the
step anyway. This has no obvious fix since `ensure()` has to return a
`Step::Output`.
Instead, this handles `download-rustc` in `impl Step for Rustc` and
`impl Step for Std`, which to my knowledge are the only build steps that
don't first go through `impl Step for Sysroot` (`Rustc` is used for
the `rustc-dev` component).
See https://github.com/rust-lang/rust/pull/79540#discussion_r563350075
and https://github.com/rust-lang/rust/issues/81930 for further context.
Here are some example runs with these changes and `download-rustc`
enabled:
```
$ x.py build src/tools/clippy
Building stage1 tool clippy-driver (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 1m 09s
Building stage1 tool cargo-clippy (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.11s
$ x.py test src/tools/clippy
Updating only changed submodules
Submodules updated in 0.01 seconds
Finished dev [unoptimized + debuginfo] target(s) in 0.09s
Building stage1 tool clippy-driver (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.09s
Building rustdoc for stage1 (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.28s
Finished release [optimized] target(s) in 15.26s
Running build/x86_64-unknown-linux-gnu/stage1-tools/x86_64-unknown-linux-gnu/release/deps/clippy_driver-8b407b140e0aa91c
test result: ok. 592 passed; 0 failed; 3 ignored; 0 measured; 0 filtered out
$ x.py build src/tools/rustdoc
Building rustdoc for stage1 (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 41.28s
Build completed successfully in 0:00:41
$ x.py test src/test/rustdoc-ui
Building stage0 tool compiletest (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.12s
Building rustdoc for stage1 (x86_64-unknown-linux-gnu)
Finished release [optimized] target(s) in 0.10s
test result: ok. 105 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 8.15s
$ x.py build compiler/rustc
Finished dev [unoptimized + debuginfo] target(s) in 0.09s
Build completed successfully in 0:00:00
```
Note a few things:
- Clippy depends on stage1 rustc-dev artifacts, but rustc didn't have to
be recompiled. Instead, the artifacts were copied automatically.
- All steps are always enabled. There is no danger of forgetting a step,
since only the entrypoints have to handle `download-rustc`.
- Building the compiler (`compiler/rustc`) automatically does no work.
Update the bootstrap compiler
This updates the bootstrap compiler, notably leaving out a change to enable semicolon in macro expressions lint, because stdarch still depends on the old behavior.
Previously, RUSTDOCFLAGS would get overriden when bootstrap set
`RUSTDOCFLAGS` itself. Propagate the flag manually, using the same logic
as `RUSTFLAGS`.
This also extracts the logic into a helper function to make sure it's
the same.
std_detect is still using this and as it's in a submodule updating it will be a
pain. We can catch this either after a stdarch submodule bump or just on the
next cycle.
Remove unnecessary `Option` in `default_doc`
Previously, there were two different ways to encode the same info: `None` or
`Some(&[])`. Now there is only one way, `&[]`.
Use format string in bootstrap panic instead of a string directly
This fixes the following warning when compiling with nightly:
```
warning: panic message is not a string literal
--> src/bootstrap/builder.rs:1515:24
|
1515 | panic!(out);
| ^^^
|
= note: `#[warn(non_fmt_panic)]` on by default
= note: this is no longer accepted in Rust 2021
help: add a "{}" format string to Display the message
|
1515 | panic!("{}", out);
| ^^^^^
help: or use std::panic::panic_any instead
|
1515 | std::panic::panic_any(out);
| ^^^^^^^^^^^^^^^^^^^^^^
```
Found while working on https://github.com/rust-lang/rust/pull/79540. cc https://github.com/rust-lang/rust/pull/81645, which landed in 1.51.
- Use the same compiler for stage0 and stage1. This should be fixed at
some point (so bootstrap isn't constantly rebuilt).
- Make sure `x.py build` and `x.py check` work.
- Use `git merge-base` to determine the most recent commit to download.
- Copy stage0 to the various sysroots in `Sysroot`, and delegate to
Sysroot in Assemble. Leave all other code unchanged.
- Rename date -> key
This can also be a commit hash, so 'date' is no longer a good name.
- Add the commented-out option to config.toml.example
- Disable all steps by default when `download-rustc` is enabled
Most steps don't make sense when downloading a compiler, because they'll
be pre-built in the sysroot. Only enable the ones that might be useful,
in particular Rustdoc and all `check` steps.
At some point, this should probably enable other tools, but rustdoc is
enough to test out `download-rustc`.
- Don't print 'Skipping' twice in a row
Bootstrap forcibly enables a dry run if it isn't already set, so
previously it would print the message twice:
```
Skipping bootstrap::compile::Std because it is not enabled for `download-rustc`
Skipping bootstrap::compile::Std because it is not enabled for `download-rustc`
```
Now it correctly only prints once.
## Future work
- Add FIXME about supporting beta commits
- Debug logging will never work. This should be fixed.
This fixes the following warning when compiling with nightly:
```
warning: panic message is not a string literal
--> src/bootstrap/builder.rs:1515:24
|
1515 | panic!(out);
| ^^^
|
= note: `#[warn(non_fmt_panic)]` on by default
= note: this is no longer accepted in Rust 2021
help: add a "{}" format string to Display the message
|
1515 | panic!("{}", out);
| ^^^^^
help: or use std::panic::panic_any instead
|
1515 | std::panic::panic_any(out);
| ^^^^^^^^^^^^^^^^^^^^^^
```
Add `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` lint
cc #79813
This PR adds an allow-by-default future-compatibility lint
`SEMICOLON_IN_EXPRESSIONS_FROM_MACROS`. It fires when a trailing semicolon in a
macro body is ignored due to the macro being used in expression
position:
```rust
macro_rules! foo {
() => {
true; // WARN
}
}
fn main() {
let val = match true {
true => false,
_ => foo!()
};
}
```
The lint takes its level from the macro call site, and
can be allowed for a particular macro by adding
`#[allow(macro_trailing_semicolon)]`.
The lint is set to warn for all internal rustc crates (when being built
by a stage1 compiler). After the next beta bump, we can enable
the lint for the bootstrap compiler as well.
This commit adds a new stable codegen option to rustc,
`-Csplit-debuginfo`. The old `-Zrun-dsymutil` flag is deleted and now
subsumed by this stable flag. Additionally `-Zsplit-dwarf` is also
subsumed by this flag but still requires `-Zunstable-options` to
actually activate. The `-Csplit-debuginfo` flag takes one of
three values:
* `off` - This indicates that split-debuginfo from the final artifact is
not desired. This is not supported on Windows and is the default on
Unix platforms except macOS. On macOS this means that `dsymutil` is
not executed.
* `packed` - This means that debuginfo is desired in one location
separate from the main executable. This is the default on Windows
(`*.pdb`) and macOS (`*.dSYM`). On other Unix platforms this subsumes
`-Zsplit-dwarf=single` and produces a `*.dwp` file.
* `unpacked` - This means that debuginfo will be roughly equivalent to
object files, meaning that it's throughout the build directory
rather than in one location (often the fastest for local development).
This is not the default on any platform and is not supported on Windows.
Each target can indicate its own default preference for how debuginfo is
handled. Almost all platforms default to `off` except for Windows and
macOS which default to `packed` for historical reasons.
Some equivalencies for previous unstable flags with the new flags are:
* `-Zrun-dsymutil=yes` -> `-Csplit-debuginfo=packed`
* `-Zrun-dsymutil=no` -> `-Csplit-debuginfo=unpacked`
* `-Zsplit-dwarf=single` -> `-Csplit-debuginfo=packed`
* `-Zsplit-dwarf=split` -> `-Csplit-debuginfo=unpacked`
Note that `-Csplit-debuginfo` still requires `-Zunstable-options` for
non-macOS platforms since split-dwarf support was *just* implemented in
rustc.
There's some more rationale listed on #79361, but the main gist of the
motivation for this commit is that `dsymutil` can take quite a long time
to execute in debug builds and provides little benefit. This means that
incremental compile times appear that much worse on macOS because the
compiler is constantly running `dsymutil` over every single binary it
produces during `cargo build` (even build scripts!). Ideally rustc would
switch to not running `dsymutil` by default, but that's a problem left
to get tackled another day.
Closes#79361
cc #79813
This PR adds an allow-by-default future-compatibility lint
`SEMICOLON_IN_EXPRESSIONS_FROM_MACROS`. It fires when a trailing semicolon in a
macro body is ignored due to the macro being used in expression
position:
```rust
macro_rules! foo {
() => {
true; // WARN
}
}
fn main() {
let val = match true {
true => false,
_ => foo!()
};
}
```
The lint takes its level from the macro call site, and
can be allowed for a particular macro by adding
`#[allow(semicolon_in_expressions_from_macros)]`.
The lint is set to warn for all internal rustc crates (when being built
by a stage1 compiler). After the next beta bump, we can enable
the lint for the bootstrap compiler as well.
Utilize PGO for rustc linux dist builds
This implements support for applying PGO to the rustc compilation step (not
standard library or any tooling, including rustdoc). Expanding PGO to more tools
is not terribly difficult but will involve more work and greater CI time
commitment.
For the same reason of avoiding greater implementation time commitment,
implementing for platforms outside of x86_64-unknown-linux-gnu is skipped.
In practice it should be quite simple to extend over time to more platforms. The
initial implementation is intentionally minimal here to avoid too much work
investment before we start seeing wins for a subset of Rust users.
The choice of workloads to profile here is somewhat arbitrary, but the general
rationale was to aim for a small set that largely avoided time regressions on
perf.rust-lang.org's full suite of crates. The set chosen is libcore, cargo (and
its dependencies), and a few ad-hoc stress tests from perf.rlo. The stress tests
are arguably the most controversial, but they benefit those cases (avoiding
regressions) and do not really remove wins from other benchmarks.
The primary next step after this PR lands is to implement support for PGO in
LLVM. It is unclear whether we can afford a full LLVM rebuild in CI, though, so
the approach taken there may need to be more staggered. rustc-only PGO seems
well affordable on linux at least, giving us up to 20% wall time wins on some
crates for 15 minutes of extra CI time (1 hour with this PR, up from 45 minutes).
The PGO data is uploaded to allow others to reuse it if attempting to reproduce
the CI build or potentially, in the future, on other platforms where an
off-by-one strategy is used for dist builds at minimal performance cost.
r? `@michaelwoerister` (but tell me if you don't want to / don't feel comfortable approving and we can find others)
This implements support for applying PGO to the rustc compilation step (not
standard library or any tooling, including rustdoc). Expanding PGO to more tools
is not terribly difficult but will involve more work and greater CI time
commitment.
For the same reason of avoiding greater time commitment, this currently avoids
implementing for platforms outside of x86_64-unknown-linux-gnu, though in
practice it should be quite simple to extend over time to more platforms. The
initial implementation is intentionally minimal here to avoid too much work
investment before we start seeing wins for a subset of Rust users.
The choice of workloads to profile here is somewhat arbitrary, but the general
rationale was to aim for a small set that largely avoided time regressions on
perf.rust-lang.org's full suite of crates. The set chosen is libcore, cargo (and
its dependencies), and a few ad-hoc stress tests from perf.rlo. The stress tests
are arguably the most controversial, but they benefit those cases (avoiding
regressions) and do not really remove wins from other benchmarks.
The primary next step after this PR lands is to implement support for PGO in
LLVM. It is unclear whether we can afford a full LLVM rebuild in CI, though, so
the approach taken there may need to be more staggered. rustc-only PGO seems
well affordable on linux at least, giving us up to 20% wall time wins on some
crates for 15 minutes of extra CI time (1 hour up from 45 minutes).
The PGO data is uploaded to allow others to reuse it if attempting to reproduce
the CI build or potentially, in the future, on other platforms where an
off-by-one strategy is used for dist builds at minimal performance cost.
`dsymutil` adds time to builds on Apple platforms for no clear benefit, and also
makes it more difficult for debuggers to find debug info. The compiler currently
defaults to running `dsymutil` to preserve its historical default, but when
compiling the compiler itself, we skip it by default since we know it's safe to
do so in that case.
Support enable/disable sanitizers/profiler per target
This PR add options under `[target.*]` of `config.toml` which can enable or disable sanitizers/profiler runtime for corresponding target.
If these options are empty, the global options under `[build]` will take effect.
Fix#78329
Compile rustc crates with the initial-exec TLS model
This should produce more efficient code, with fewer calls to
__tls_get_addr. The tradeoff is that libraries using it won't work with
dlopen, but that shouldn't be a problem for rustc's internal libraries.
This should produce more efficient code, with fewer calls to
__tls_get_addr. The tradeoff is that libraries using it won't work with
dlopen, but that shouldn't be a problem for tools or for our own
internal libraries.
Co-authored-by: Mark Rousskov <mark.simulacrum@gmail.com>
Fix `x.py clippy`
I don't think this ever worked.
Fixes https://github.com/rust-lang/rust/issues/77309. `--fix` support is a work in progress, but works for a very small subset of `libtest`.
This works by using the host `cargo-clippy` driver; it does not use `stage0.txt` at all. To mitigate confusion from this, it gives an error if you don't have `rustc +nightly` as the default rustc in `$PATH`. Additionally, it means that bootstrap can't set `RUSTC`; this makes it no longer possible for clippy to detect the sysroot itself. Instead, bootstrap passes the sysroot to cargo.
r? `@ghost`
Here's the error for rustdoc:
```
Checking rustdoc artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
error: no library targets found in package `rustdoc-tool`
```
Clippy does its own runtime detection of the sysroot, which was
incorrect in this case (it used the beta sysroot). This overrides the
sysroot to use `stage0-sysroot` instead.
- Get `x.py clippy` to work on nightly
- Give a nice error message if nightly clippy isn't installed
Improve build-manifest to work with the improved promote-release
This PR makes some changes to build-manifest to have it work better with the other improvements I'm making to [promote-release](https://github.com/rust-lang/promote-release).
A new way to invoke the tool was added: `./x.py run src/tools/build-manifest`. The new invocation disables the generation of `.sha256` files and the generation of GPG signatures, as those steps are not tied to the Rust version we're building the manifest of: handling them in `promote-release` will improve the maintenability of our release process. Invocations through the old command (`./x.py dist hash-and-sign`) are referred inside the source code as "legacy". The new invocation also enables internal parallelism, disabled on legacy to avoid overloading our old server.
Improvements were also made on how the checksums included in the manifest are generated:
* The manifest is first generated with placeholder checksums, and then a function walks through the manifes and calculates only the needed hashes. Before this PR, all the hashes were calculated beforehand, including the hashes of unused files.
* Calculating the hashes is now done in parallel with rayon, to better utilize all the available disk bandwidth.
* The `sha2` crate is now used instead of the `sha256sum` CLI tool: this avoids the overhead of calling another process, but more importantly enables hardware acceleration whenever available (the `sha256sum` CLI tool doesn't support it at all).
r? @Mark-Simulacrum
This PR is best reviewed commit-by-commit.
This matches Cargo behavior and avoids the (somewhat expensive) double checking,
as well as the unfortunate duplicate error messages (#76822,
rust-lang/cargo#5128).
- Suggest `x.py setup` if config.toml doesn't exist yet (twice, once
before and once after the build)
- Prompt for a profile if not given on the command line
- Print the configuration file that will be used
- Print helpful starting commands after setup
- Link to the dev-guide after finishing
- Note that distro maintainers will see the changelog warning
The performance difference is negligible, but it makes me feel better.
Note that this does not remove some clones in `config`, because it would
require changing the logic around (and performance doesn't matter
for bootstrap).
Fix generating rustc docs with non-default lib directory.
If `libdir` is set in `config.toml`, then the tool to generate the rustc docs was unable to run `rustc` because it could not find the shared libraries. The solution is to set the dylib search path to include the libdir.
I changed the API of `add_rustc_lib_path` to take `Command` instead of `Cargo` to try to share the code in several places. This is how it worked before https://github.com/rust-lang/rust/pull/64316, and I think this still retains the spirit of that change.
Fixes#76702
Make the default stage for x.py configurable
This also allows configuring each sub-command individually.
Possibly #76617 should land before this? I don't feel strongly either way, I don't mind waiting.
Closes https://github.com/rust-lang/rust/issues/76165.
r? `@Mark-Simulacrum`
This allows configuring the default stage for each sub-command individually.
- Normalize the stage as early as possible, so there's no confusion
about which to use.
- Don't add an explicit `stage` option in config.toml
This offers no more flexibility than `*_stage` and makes it confusing
which takes precedence.
- Always give `--stage N` precedence over config.toml
- Fix bootstrap tests
This changes the tests to go through `Config::parse` so that they test
the actual defaults, not the dummy ones provided by `default_opts`. To
make this workable (and independent of the environment), it does not
read `config.toml` for tests.
Add host triples to CI builders
This is a follow-up to #76415, which changed how x.py interprets cross-compilation target/host flags. This should fix the known cases, but I'm still working through CI logs before/after that PR to identify if anything else is missing.
It is really painful to inspect differences in what was built in CI if things
are appearing and disappearing randomly as they hover around the 100ms mark. No
matter what we choose there's always going to be quite a bit of variability on
CI in timing, so we're going to see things appear and vanish.
rustc is a natively cross-compiling compiler, and generally none of our steps
should care whether they are using a compiler built of triple A or B, just the
--target directive being passed to the running compiler. e.g., when building for
some target C, you don't generally want to build two stds: one with a host A
compiler and the other with a host B compiler. Just one std is sufficient.
rustbuild: Build tests with LLD if `use-lld = true` was passed
Addresses https://github.com/rust-lang/rust/pull/76127#discussion_r479932392.
Our test suite is generally ready to run with an explicitly specified linker (https://github.com/rust-lang/rust/pull/45191),
so LLD specified with `use-lld = true` works as well.
Only 4 tests fail (on `x86_64-pc-windows-msvc`):
```
ui/panic-runtime/lto-unwind.rs
run-make-fulldeps/debug-assertions
run-make-fulldeps/foreign-exceptions
run-make-fulldeps/test-harness
```
All of them are legitimate issues with LLD (or at least with combination Rust+LLD) and manifest in segfaults on access to TLS (https://github.com/rust-lang/rust/pull/76127#issuecomment-683473325). UPD: These issues are caused by https://github.com/rust-lang/rust/issues/72145 and appear because I had `-Ctarget-cpu=native` set.
UPD: Further commits build tests with LLD for non-MSVC targets and propagate LLD to more places when `use-lld` is enabled.
This currently includes libLLVM, llvm-config, and FileCheck, but will perhaps
expand to more tooling overtime. It should be considered entirely unstable and
may change at any time.
Often when modifying compiler code you'll miss that you've changed an API used
by unit tests, since x.py check didn't previously catch that.
It's also useful to have this for editing with rust-analyzer and similar tooling
where editing tests previously didn't notify you of errors in test files.
Add option to use the new symbol mangling in rustc/std
I don't know if this causes problems in some cases -- maybe it should be on by default for at least rustc. I've never encountered problems with it other than tools not supporting it, though.
cc @nnethercote
r? @eddyb
- Use stage 2 for makefile
- Move assert to builder
- Don't add an assert for --help
- Allow --stage 0 if passed explicitly
- Don't assert defaults during tests
Otherwise it's impossible to test the defaults!
### x.py build/test: stage 1
I've seen very few people who actually use full stage 2 builds on purpose. These compile rustc and libstd twice and don't give you much more information than a stage 1 build (except in rare cases like https://github.com/rust-lang/rust/pull/68692#discussion_r376392145). For new contributors, this makes the build process even more daunting than it already is. As long as CI is changed to use `--stage 2` I see no downside here.
### x.py bench/dist/install: stage 2
These commands have to do with a finished, optimized version of rustc. It seems very rare to want to use these with a stage 1 build.
### x.py doc: stage 0
Normally when you document things you're just fixing a typo. In this case there is no need to build the whole rust compiler, since the documentation will usually be the same when generated with the beta compiler or with stage 1.
Note that for this release cycle only there will be a significant different between stage0 and stage1 docs: https://github.com/rust-lang/rust/pull/73101. However most of the time this will not be the case.
Stabilize control-flow-guard codegen option
This is the stabilization PR discussed in #68793. It converts the `-Z control-flow-guard` debugging option into a codegen option (`-C control-flow-guard`), and changes the associated tests.
Generating the coverage map
@tmandry @wesleywiser
rustc now generates the coverage map and can support (limited)
coverage report generation, at the function level.
Example commands to generate a coverage report:
```shell
$ BUILD=$HOME/rust/build/x86_64-unknown-linux-gnu
$ $BUILD/stage1/bin/rustc -Zinstrument-coverage \
$HOME/rust/src/test/run-make-fulldeps/instrument-coverage/main.rs
$ LLVM_PROFILE_FILE="main.profraw" ./main
called
$ $BUILD/llvm/bin/llvm-profdata merge -sparse main.profraw -o main.profdata
$ $BUILD/llvm/bin/llvm-cov show --instr-profile=main.profdata main
```
r? @wesleywiser
Rust compiler MCP rust-lang/compiler-team#278
Relevant issue: #34701 - Implement support for LLVMs code coverage instrumentation
Teach bootstrap about target files vs target triples
`rustc` allows passing in predefined target triples as well as JSON
target specification files. This change allows bootstrap to have the
first inkling about those differences. This allows building a
cross-compiler for an out-of-tree architecture (even though that
compiler won't work for other reasons).
Even if no one ever uses this functionality, I think the newtype
around the `Interned<String>` improves the readability of the code.
`rustc` allows passing in predefined target triples as well as JSON
target specification files. This change allows bootstrap to have the
first inkling about those differences. This allows building a
cross-compiler for an out-of-tree architecture (even though that
compiler won't work for other reasons).
Even if no one ever uses this functionality, I think the newtype
around the `Interned<String>` improves the readability of the code.
The current plan is that submodule tracks the `release` branch of
rust-analyzer, which is updated once a week.
rust-analyzer is a workspace (with a virtual manifest), the actual
binary is provide by `crates/rust-analyzer` package.
Note that we intentionally don't add rust-analyzer to `Kind::Test`,
for two reasons.
*First*, at the moment rust-analyzer's test suite does a couple of
things which might not work in the context of rust repository. For
example, it shells out directly to `rustup` and `rustfmt`. So, making
this work requires non-trivial efforts.
*Second*, it seems unlikely that running tests in rust-lang/rust repo
would provide any additional guarantees. rust-analyzer builds with
stable and does not depend on the specifics of the compiler, so
changes to compiler can't break ra, unless they break stability
guarantee. Additionally, rust-analyzer itself is gated on bors, so we
are pretty confident that test suite passes.
This commit moves the compiler-builtins-specific build logic from
`src/bootstrap/bin/rustc.rs` into the workspace `Cargo.toml`'s
`[profile]` configuration. Now that rust-lang/cargo#7253 is fixed we can
ensure that Cargo knows about debug assertions settings, and it can also
be configured to specifically disable debug assertions unconditionally
for compiler-builtins. This should improve rebuild logic when
debug-assertions settings change and also improve build-std integration
where Cargo externally now has an avenue to learn how to build
compiler-builtins as well.
Speed up bootstrap a little.
The bootstrap script was calling `cargo metadata` 3 times (or 6 with `-v`). This is a very expensive operation, and this attempts to avoid the extra calls. On my system, a simple command like `./x.py test -h -v` goes from about 3 seconds to 0.4.
An overview of the changes:
- Call `cargo metadata` only once with `--no-deps`. Optional dependencies are filtered in `in_tree_crates` (handling `profiler_builtins` and `rustc_codegen_llvm` which are driven by the config).
- Remove a duplicate call to `metadata::build` when using `-v`. I'm not sure why it was there, it looks like a mistake or vestigial from previous behavior.
- Remove check for `_shim`, I believe all the `_shim` crates are now gone.
- Remove check for `rustc_` and `*san` for `test::Crate::should_run`, these are no longer dependencies in the `test` tree.
- Use relative paths in `./x.py test -h -v` output.
- Some code cleanup (remove unnecessary `find_compiler_crates`, etc.).
- Show suite paths (`src/test/ui/...`) in `./x.py test -h -v` output.
- Some doc comments.
Remove vestigial CI job msvc-aux.
This CI job isn't really doing anything, so it seems prudent to remove it.
For some history:
* This was introduced in #48809 when the msvc job was split in two to keep it under 2 hours (oh the good old days). At the time, this check-aux job did a bunch of things:
* tidy
* src/test/pretty
* src/test/run-pass/pretty
* src/test/run-fail/pretty
* src/test/run-pass-valgrind/pretty
* src/test/run-pass-fulldeps/pretty
* src/test/run-fail-fulldeps/pretty
* Tidy was removed in #60777.
* run-pass and run-pass-fulldeps moved to UI in #63029
* src/test/pretty removed in #58140
* src/test/run-fail moved to UI in #71185
* run-fail-fulldeps removed in #51285
Over time through attrition, the job was left with one lonely thing: `src/test/run-pass-valgrind/pretty`. And of course, this wasn't actually running the "pretty" tests. The normal `run-pass-valgrind` tests ran, and then when it tried to run in "pretty" mode, all the tests were ignored because compiletest thought nothing had changed (apparently compiletest isn't fingerprinting the mode? Needs more investigation…). `run-pass-valgrind` is already being run as part of `x86_64-msvc-1`, so there's no need to run it here.
I've taken the liberty of removing `src/test/run-pass-valgrind/pretty` as a distinct test. I'm guessing from the other PR's that the pretty tests should now live in `src/test/pretty`, and that the team has moved away from doing pretty tests on other parts of the `src/test` tree.
This should run much faster.
There are also some drive-by cleanups here to try to simplify things.
Also, the paths for in-tree crates are now displayed as relative
in `x.py test -h -v`.
Provide separate option for std debug asserts
On local one-off benchmarking of libcore metadata-only, debug asserts in std are a significant hit (15s to 20s). Provide an option for compiler developers to disable them. A build with a nightly compiler is around 10s, for reference.
bootstrap: remove lldb dist packaging
The lldb-preview rustup package is missing on every single target, and has never been shipped beyond x86_64-apple-darwin. It was removed in #62592 which landed around a year ago, and there's not been demand that we re-enable it since, so we're now removing support entirely to cleanup the code a bit.
The hope is that this will also kill the useless "lldb-preview" row on https://rust-lang.github.io/rustup-components-history/.
Enable Control Flow Guard in rustbuild
Now that Rust supports Control Flow Guard (#68180), add a config.toml option to build the standard library with CFG enabled.
r? @nagisa
Add an option to use LLD to link the compiler on Windows platforms
Based on https://github.com/rust-lang/rust/pull/68609.
Using LLD is good way to improve compile times on Windows since `link.exe` is quite slow. The time for `x.py build --stage 1 src/libtest` goes from 0:12:00 to 0:08:29. Compile time for `rustc_driver` goes from 226.34s to 18.5s. `rustc_macros` goes from 28.69s to 7.7s. The size of `rustc_driver` is also reduced from 83.3 MB to 78.7 MB.
r? @Mark-Simulacrum
Clear out target directory if compiler has changed
Previously, we relied fully on Cargo to detect that the compiler had changed and
it needed to rebuild the standard library (or later "components"). This used to
not quite be the case prior to moving to LLVM be a separate cargo invocation;
subsequent compiles would recompile std and friends if LLVM had changed
(#67077 is the PR that changes things here).
This PR moves us to clearing out libstd when it is being compiled if the rustc
we're using has changed. We fairly harshly limit the cases in which we do this
(e.g., ignoring dry run mode, and so forth, as well as rustdoc invocations).
This is primarily because when we're not using the compiler directly, so
clearing out in other cases is likely to lead to bugs, particularly as our
deletion scheme is pretty blunt today (basically removing more than is needed,
i.e., not just the rustc artifacts).
In practice, this targeted fix does fix the known bug, though it may not fully
resolve the problem here. It's also not clear that there is a full fix hiding
here that doesn't involve a more major change (like -Zbinary-dep-depinfo was).
As a drive-by fix, don't delete the compiler before calling Build::copy, as that
also deletes the compiler.
Previously, we relied fully on Cargo to detect that the compiler had changed and
it needed to rebuild the standard library (or later "components"). This used to
not quite be the case prior to moving to LLVM be a separate cargo invocation;
subsequent compiles would recompile std and friends if LLVM had changed
(#67077 is the PR that changes things here).
This PR moves us to clearing out libstd when it is being compiled if the rustc
we're using has changed. We fairly harshly limit the cases in which we do this
(e.g., ignoring dry run mode, and so forth, as well as rustdoc invocations).
This is primarily because when we're not using the compiler directly, so
clearing out in other cases is likely to lead to bugs, particularly as our
deletion scheme is pretty blunt today (basically removing more than is needed,
i.e., not just the rustc artifacts).
In practice, this targeted fix does fix the known bug, though it may not fully
resolve the problem here. It's also not clear that there is a full fix hiding
here that doesn't involve a more major change (like -Zbinary-dep-depinfo was).
As a drive-by fix, don't delete the compiler before calling Build::copy, as that
also deletes the compiler.
Bootstrap: change logic for choosing linker and rpath
This is a follow-up from #66957 and #67023. Apparently there was one more location with a hard-coded list of targets to influence linking.
I've filed #67171 to track this madness.
r? @alexcrichton
This commit builds on #65501 continue to simplify the build system and
compiler now that we no longer have multiple LLVM backends to ship by
default. Here this switches the compiler back to what it once was long
long ago, which is linking LLVM directly to the compiler rather than
dynamically loading it at runtime. The `codegen-backends` directory of
the sysroot no longer exists and all relevant support in the build
system is removed. Note that `rustc` still supports a dynamically loaded
codegen backend as it did previously, it just no longer supports
dynamically loaded codegen backends in its own sysroot.
Additionally as part of this the `librustc_codegen_llvm` crate now once
again explicitly depends on all of its crates instead of implicitly
loading them through the sysroot. This involved filling out its
`Cargo.toml` and deleting all the now-unnecessary `extern crate`
annotations in the header of the crate. (this in turn required adding a
number of imports for names of macros too).
The end results of this change are:
* Rustbuild's build process for the compiler as all the "oh don't forget
the codegen backend" checks can be easily removed.
* Building `rustc_codegen_llvm` is much simpler since it's simply
another compiler crate.
* Managing the dependencies of `rustc_codegen_llvm` is much simpler since
it's "just another `Cargo.toml` to edit"
* The build process should be a smidge faster because there's more
parallelism in the main rustc build step rather than splitting
`librustc_codegen_llvm` out to its own step.
* The compiler is expected to be slightly faster by default because the
codegen backend does not need to be dynamically loaded.
* Disabling LLVM as part of rustbuild is still supported, supporting
multiple codegen backends is still supported, and dynamic loading of a
codegen backend is still supported.
This is not yet actually used by CI, but implements the logic for
checking that tools are properly building on beta/stable and during beta
cutoff week.
This attempts to mirror the checking functionality in
src/ci/docker/x86_64-gnu-tools/checktools.sh, and called scripts. It
does not attempt to run the relevant steps (that functionality was
originally desired to be moved into bootstrap as well, but doing so
proved more difficult than expected).
This is intended as a way to centralize and make clearer the logic
involved in toolstate checking. In particular, the previous logic was
spread across numerous python and shell scripts in such a way that made
interpretation quite difficult.
Use a relative bindir for rustdoc to find rustc
In bootstrap, we set `RUSTC_INSTALL_BINDIR` to `config.bindir`, so
rustdoc can find rustc relative to the toolchain sysroot. However, if a
distro script like Fedora's `%configure` sets an absolute path, then
rustdoc's `sysroot.join(bin_path)` ignores that sysroot altogether.
That would be OK once the toolchain is actually installed, but it breaks
the in-tree doc tests during the build, since `/usr/bin/rustc` is still
the old version. So now we try to make `RUSTC_INSTALL_BINDIR` relative
to the sysroot prefix in the first place.
r? @Mark-Simulacrum
In bootstrap, we set `RUSTC_INSTALL_BINDIR` to `config.bindir`, so
rustdoc can find rustc relative to the toolchain sysroot. However, if a
distro script like Fedora's `%configure` sets an absolute path, then
rustdoc's `sysroot.join(bin_path)` ignores that sysroot altogether.
That would be OK once the toolchain is actually installed, but it breaks
the in-tree doc tests during the build, since `/usr/bin/rustc` is still
the old version. So now we try to make `RUSTC_INSTALL_BINDIR` relative
to the sysroot prefix in the first place.
Split the rustc target libraries into separate rustc-dev component
This is re-applies a squashed version of #64823 as well as including #65337 to fix bugs noted after merging the first PR.
The second PR is confirmed as fixing windows-gnu, and presumably also fixes other platforms, such as musl (i.e. #65335 should be fixed); `RUSTUP_DIST_SERVER=https://dev-static.rust-lang.org rustup toolchain install nightly-2019-10-16` can be installed to confirm that this is indeed the case.
- Compatible with Emscripten 1.38.46-upstream or later upstream.
- Refactors the Emscripten target spec to share code with other wasm
targets.
- Replaces the old incorrect wasm32 C call ABI with the correct one,
preserving the old one as wasm32_bindgen_compat for wasm-bindgen
compatibility.
- Updates the varargs ABI used by Emscripten and deletes the old one.
- Removes the obsolete wasm32-experimental-emscripten target.
- Uses EMCC_CFLAGS on CI to avoid the timeout problems with #63649.
This splits out a rustc-dev component with the compiler crates, and
keeps the status quo of default installed files on nightly. The default
changing to not install compiler libraries by default is left for a
future pull request.
However, on stable and beta, this does remove the compiler libraries
from the set of libraries installed by default, as they are never needed
there (per our stability story, they "cannot" be used).
minimize the rust-std component
This changes the `rust-std` dist component to only include the artifacts of compiling the `libstd` step, as listed in `.libstd.stamp`. This does include `test` and `proc-macro` as well. The remaining _unstable_ libraries that are built as part of `rustc` are packaged into a new `rustc-dev` component, intended for use in the development of closely related tools (clippy, miri, rls).
Here are the component sizes from the [try build](https://dev-static.rust-lang.org/dist/2019-10-07/index.html):
| Name | Size
| --- | ---
| rust-std-nightly-x86_64-unknown-linux-gnu.tar.gz | 23.94 MiB
| rust-std-nightly-x86_64-unknown-linux-gnu.tar.xz | 17.4 MiB
| rustc-dev-nightly-x86_64-unknown-linux-gnu.tar.gz | 182.03 MiB
| rustc-dev-nightly-x86_64-unknown-linux-gnu.tar.xz | 157.91 MiB
Fixes#61978Fixes#62486
This is needed to ensure that the crates during a normal build are
shared with the crates during testing, otherwise they'll end up hasing
differently and we'll recompile crates like `core` during tests.
This commit changes the return type of `Builder::cargo` to return a
builder that allows dynamically adding more `RUSTFLAGS` values
after-the-fact. While not used yet, this will later be used to delete
more of `rustc.rs`
Most of `bootstrap/bin/rustc.rs` doesn't need to exist with the advent
of `RUSTFLAGS` (yes this is super old) so this starts by refactoring a
bit to make it easier locally in the `Builder::cargo` method to append
to `RUSTFLAGS` that gets down to rustc.
This ensures that the failure cases for finding the codegen backend and
for finding the rustc binary are essentially the same, and since we
almost always will load the codegen backend, this is essentially meaning
that the rustc change is not a regression.
Since its inception rustbuild has always worked in three stages: one for
libstd, one for libtest, and one for rustc. These three stages were
architected around crates.io dependencies, where rustc wants to depend
on crates.io crates but said crates don't explicitly depend on libstd,
requiring a sysroot assembly step in the middle. This same logic was
applied for libtest where libtest wants to depend on crates.io crates
(`getopts`) but `getopts` didn't say that it depended on std, so it
needed `std` built ahead of time.
Lots of time has passed since the inception of rustbuild, however,
and we've since gotten to the point where even `std` itself is depending
on crates.io crates (albeit with some wonky configuration). This
commit applies the same logic to the two dependencies that the `test`
crate pulls in from crates.io, `getopts` and `unicode-width`. Over the
many years since rustbuild's inception `unicode-width` was the only
dependency picked up by the `test` crate, so the extra configuration
necessary to get crates building in this crate graph is unlikely to be
too much of a burden on developers.
After this patch it means that there are now only two build phasese of
rustbuild, one for libstd and one for rustc. The libtest/libproc_macro
build phase is all lumped into one now with `std`.
This was originally motivated by rust-lang/cargo#7216 where Cargo was
having to deal with synthesizing dependency edges but this commit makes
them explicit in this repository.
This patch supports less behavior than before, since specifiying stage 1
vs stage 2 is no longer possible, but that is presumably a somewhat rare
use case anyway, so not supporting it seems acceptable (and it can be
readded easily if desired).
