This commit fixes several issues in the fuchsia-test-runner.py script:
1. Migrate from `pm` to `ffx` for package management, as `pm` is now
deprecated. Furthermore, the `pm` calls used in this script no longer
work at Fuchsia's HEAD. This is the largest change in this commit, and
impacts all steps around repository management (creation and
registration of the repo, as well as package publishing).
2. Allow for `libtest` to be either statically or dynamically linked.
The script assumed it was dynamically linked, but the current Rust
behavior at HEAD is to statically link it.
3. Minor cleanup to use `ffx --machine json` rather than string parsing.
4. Minor cleanup to the docs around the script.
Make check-cfg docs more user-friendly
This PR improves the `--check-cfg` to make them more user-friendly by:
- explaining the purpose of the feature
- removing the "form" jargon
- making it (bit) less formal and more "friendly"
- making the doc less cluttered
- and by fixing (the width and flags) of the examples
`@rustbot` label +F-check-cfg
Change `SIGPIPE` ui from `#[unix_sigpipe = "..."]` to `-Zon-broken-pipe=...`
In the stabilization [attempt](https://github.com/rust-lang/rust/pull/120832) of `#[unix_sigpipe = "sig_dfl"]`, a concern was [raised ](https://github.com/rust-lang/rust/pull/120832#issuecomment-2007394609) related to using a language attribute for the feature: Long term, we want `fn lang_start()` to be definable by any crate, not just libstd. Having a special language attribute in that case becomes awkward.
So as a first step towards the next stabilization attempt, this PR changes the `#[unix_sigpipe = "..."]` attribute to a compiler flag `-Zon-broken-pipe=...` to remove that concern, since now the language is not "contaminated" by this feature.
Another point was [also raised](https://github.com/rust-lang/rust/pull/120832#issuecomment-1987023484), namely that the ui should not leak **how** it does things, but rather what the **end effect** is. The new flag uses the proposed naming. This is of course something that can be iterated on further before stabilization.
Tracking issue: https://github.com/rust-lang/rust/issues/97889
In the stabilization attempt of `#[unix_sigpipe = "sig_dfl"]`, a concern
was raised related to using a language attribute for the feature: Long
term, we want `fn lang_start()` to be definable by any crate, not just
libstd. Having a special language attribute in that case becomes
awkward.
So as a first step towards towards the next stabilization attempt, this
PR changes the `#[unix_sigpipe = "..."]` attribute to a compiler flag
`-Zon-broken-pipe=...` to remove that concern, since now the language
is not "contaminated" by this feature.
Another point was also raised, namely that the ui should not leak
**how** it does things, but rather what the **end effect** is. The new
flag uses the proposed naming. This is of course something that can be
iterated on further before stabilization.
Arm bare-metal target doc changes
Updates the Arm bare-metal target docs:
* Detailed pages for all the Cortex-M targets, including details about setting target-cpu and target-features to suit specific Arm models
* More detail about the difference between `eabi` and `eabihf`
* Marks the Embedded Devices Working Group Cortex-M Team as the maintainer of the Cortex-M targets
rustc: document the jobserver
Explicitly document that the jobserver may be used by `rustc`, as well as recommend the `+` indicator for integration of `rustc` into GNU Make.
In particular, show the warning to increase the chances that this document is found when searching for solutions online.
In addition, add a note about the issue with GNU Make 4.3 since it is important that users realize they should do this even if they do not expect parallelism from `rustc`.
Finally, show how to workaround the issue of `$(shell ...)` calls in recursive Make (which e.g. was needed for the Linux kernel).
The GNU Make 4.4 case under `--jobserver-style=pipe` is not added since it got fixed after Rust 1.76.0 already (i.e. `rustc` will not warn if it finds the negative file descriptors).
From: https://github.com/rust-lang/rust/issues/120515
Cc: `@petrochenkov` `@belovdv` `@weihanglo` `@bjorn3`
---
v2: To be able to use tab characters for the Make examples, add `<!-- ignore-tidy-{check} -->` support to `tidy`.
v3: Added "Integration with build systems" section to hold the GNU Make one. Added "by clearing the `MAKEFLAGS` variable". Added "aforementioned" so that it is clear we are talking about the warning above.
v4: Added CMake subsection. Added a note that `rustc` may be affected by other flags, e.g. `CARGO_MAKEFLAGS`.
v5: Added that `rustc` will choose the number of jobs if a jobserver is not passed.
Yes it looks weird, but this is how Arm write it now.
I left ARM64 alone, because it's a Microsoft/Apple term but not an Arm term (they have Armv8-A and Armv9-A architectures, which say that A64 instructions are executed when in the Aarch64 state), and I don't want to get into that, especially for a Tier 1 target.
Explicitly document that the jobserver may be used by `rustc` and show
the warning to increase the chances that this document is found when
searching for solutions online.
In particular, add a section about the interaction with build systems,
which is intended to contain recommendations on how to integrate `rustc`
with different built systems.
For GNU Make, recommend using the `+` indicator. In addition, add a
note about the issue with GNU Make 4.3 since it is important that users
realize they should do this even if they do not expect parallelism from
`rustc`. Finally, show how to workaround the issue of `$(shell ...)`
calls in recursive Make (which e.g. was needed for the Linux kernel).
The GNU Make 4.4 case under `--jobserver-style=pipe` is not added since
it got fixed after Rust 1.76.0 already (i.e. `rustc` will not warn if
it finds the negative file descriptors).
For CMake, recommend using `JOB_SERVER_AWARE` and show a workaround using
`$(MAKE)` for earlier versions (when using the Makefile generator).
From: https://github.com/rust-lang/rust/issues/120515
Cc: @petrochenkov @belovdv @weihanglo @bjorn3
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`-Z debug-macros` is "stabilized" by enabling it by default and removing.
`-Z collapse-macro-debuginfo` is stabilized as `-C collapse-macro-debuginfo`.
It now supports all typical boolean values (`parse_opt_bool`) in addition to just yes/no.
Default value of `collapse_debuginfo` was changed from `false` to `external` (i.e. collapsed if external, not collapsed if local).
`#[collapse_debuginfo]` attribute without a value is no longer supported to avoid guessing the default.
Ignore `-C strip` on MSVC
tl;dr - Define `-Cstrip` to only ever affect the binary; no other build artifacts.
This is necessary to improve cross-platform behavior consistency: if someone wanted debug information to be contained only in separate files on all platforms, they would set `-Cstrip=symbols` and `-Csplit-debuginfo=packed`, but this would result in no PDB files on MSVC.
Resolves#114215
Implement Modified Condition/Decision Coverage
This is an implementation based on llvm backend support (>= 18) by `@evodius96` and branch coverage support by `@Zalathar.`
### Major changes:
* Add -Zcoverage-options=mcdc as switch. Now coverage options accept either `no-branch`, `branch`, or `mcdc`. `mcdc` also enables `branch` because it is essential to work.
* Add coverage mapping for MCDCBranch and MCDCDecision. Note that MCDCParameter evolves from llvm 18 to llvm 19. The mapping in rust side mainly references to 19 and is casted to 18 types in llvm wrapper.
* Add wrapper for mcdc instrinc functions from llvm. And inject associated statements to mir.
* Add BcbMappingKind::Decision, I'm not sure is it proper but can't find a better way temporarily.
* Let coverage-dump support parsing MCDCBranch and MCDCDecision from llvm ir.
* Add simple tests to check whether mcdc works.
* Same as clang, currently rustc does not generate instrument for decision with more than 6 condtions or only 1 condition due to considerations of resource.
### Implementation Details
1. To get information about conditions and decisions, `MCDCState` in `BranchInfoBuilder` is used during hir lowering to mir. For expressions with logical op we call `Builder::visit_coverage_branch_operation` to record its sub conditions, generate condition ids for them and save their spans (to construct the span of whole decision). This process mainly references to the implementation in clang and is described in comments over `MCDCState::record_conditions`. Also true marks and false marks introduced by branch coverage are used to detect where the decision evaluation ends: the next id of the condition == 0.
2. Once the `MCDCState::decision_stack` popped all recorded conditions, we can ensure that the decision is checked over and push it into `decision_spans`. We do not manually insert decision span to avoid complexity from then_else_break in nested if scopes.
3. When constructing CoverageSpans, add condition info to BcbMappingKind::Branch and decision info to BcbMappingKind::Decision. If the branch mapping has non-zero condition id it will be transformed to MCDCBranch mapping and insert `CondBitmapUpdate` statements to its evaluated blocks. While decision bcb mapping will insert `TestVectorBitmapUpdate` in all its end blocks.
### Usage
```bash
echo "[build]\nprofiler=true" >> config.toml
./x build --stage 1
./x test tests/coverage/mcdc_if.rs
```
to build the compiler and run tests.
```shell
export PATH=path/to/llvm-build:$PATH
rustup toolchain link mcdc build/host/stage1
cargo +mcdc rustc --bin foo -- -Cinstrument-coverage -Zcoverage-options=mcdc
cd target/debug
LLVM_PROFILE_FILE="foo.profraw" ./foo
llvm-profdata merge -sparse foo.profraw -o foo.profdata
llvm-cov show ./foo -instr-profile=foo.profdata --show-mcdc
```
to check "foo" code.
### Problems to solve
For now decision mapping will insert statements to its all end blocks, which may be optimized by inserting a final block of the decision. To do this we must also trace the evaluated value at each end of the decision and join them separately.
This implementation is not heavily tested so there should be some unrevealed issues. We are going to check our rust products in the next. Please let me know if you had any suggestions or comments.
Introduce perma-unstable `wasm-c-abi` flag
Now that `wasm-bindgen` v0.2.88 supports the spec-compliant C ABI, the idea is to switch to that in a future version of Rust. In the meantime it would be good to let people test and play around with it.
This PR introduces a new perma-unstable `-Zwasm-c-abi` compiler flag, which switches to the new spec-compliant C ABI when targeting `wasm32-unknown-unknown`.
Alternatively, we could also stabilize this and then deprecate it when we switch. I will leave this to the Rust maintainers to decide.
This is a companion PR to #117918, but they could be merged independently.
MCP: https://github.com/rust-lang/compiler-team/issues/703
Tracking issue: https://github.com/rust-lang/rust/issues/122532
Add support for Arm64EC to the Standard Library
Adds the final pieces so that the standard library can be built for arm64ec-pc-windows-msvc (initially added in #119199)
* Bumps `windows-sys` to 0.56.0, which adds support for Arm64EC.
* Correctly set the `isEC` parameter for LLVM's `writeArchive` function.
* Add `#![feature(asm_experimental_arch)]` to library crates where Arm64EC inline assembly is used, as it is currently unstable.
Update how WASI toolchains are used in CI and bootstrap
This commit updates how the WASI targets are configured with their toolchain. Long ago a `config.toml` option of `wasi-root` was added to enable building with the WASI files produced by wasi-libc. Additionally for CI testing and release building the Rust toolchain has been using a hard-coded commit of wasi-libc which is bundled with the release of the `wasm32-wasip1` target, for example.
Nowadays though the wasi-sdk project, the C/C++ toolchain for WASI, is the go-to solution for compiling/linking WASI code and contains the more-or-less official releases of wasi-libc. This commit migrates CI to using wasi-sdk releases and additionally updates `bootstrap` to recognize when this is configured. This means that with `$WASI_SDK_PATH` configured there's no further configuration necessary to get a working build. Notably this also works better for the new targets of WASI as well, such as `wasm32-wasip2` and `wasm32-wasip1-threads` where the wasi-sdk release now has libraries for all targets bundled within it.
