Implement printing of stack traces on LLVM segfaults and aborts
Implement #79153
Based on discussion, try to extend the rust_backtrace=1 feature to handle segfault or aborts in the llvm backend
Remove unused dependencies from compiler crates
Various compiler crates have dependencies that they don't appear to use. I used some scripting to detect such dependencies, filtered them based on some manual review, and removed those that do indeed appear to be entirely unused.
Find codegen backends in more locations
* Search in the sysroot passed using `--sysroot` in addition to the default sysroot.
* Search for `librustc_codegen_$name.so` in addition to `librustc_codegen_$name-$release.so`.
This combined would allow putting `librustc_codegen_cranelift.so` in the right location of a sysroot passed using `--sysroot`.
- Add back `HirIdVec`, with a comment that it will soon be used.
- Add back `*_region` functions, with a comment they may soon be used.
- Remove `-Z borrowck_stats` completely. It didn't do anything.
- Remove `make_nop` completely.
- Add back `current_loc`, which is used by an out-of-tree tool.
- Fix style nits
- Remove `AtomicCell` with `cfg(parallel_compiler)` for consistency.
Found with https://github.com/est31/warnalyzer.
Dubious changes:
- Is anyone else using rustc_apfloat? I feel weird completely deleting
x87 support.
- Maybe some of the dead code in rustc_data_structures, in case someone
wants to use it in the future?
- Don't change rustc_serialize
I plan to scrap most of the json module in the near future (see
https://github.com/rust-lang/compiler-team/issues/418) and fixing the
tests needed more work than I expected.
TODO: check if any of the comments on the deleted code should be kept.
Add `-Z unpretty` flags for the AST
Implements rust-lang/compiler-team#408.
Builds on #82269, but if that PR is rejected or stalls out, I can implement this without #82269.
cc rust-lang/rustc-dev-guide#1062
Cleanup `PpMode` and friends
This PR:
- Separates `PpSourceMode` and `PpHirMode` to remove invalid states
- Renames the variant to remove the redundant `Ppm` prefix
- Adds basic documentation for the different pretty-print modes
- Cleanups some code to make it more idiomatic
Not sure if this is actually useful, but it looks cleaner to me.
Rollup of 7 pull requests
Successful merges:
- #80595 (`impl PartialEq<Punct> for char`; symmetry for #78636)
- #81991 (Fix panic in 'remove semicolon' when types are not local)
- #82176 (fix MIR fn-ptr pretty-printing)
- #82244 (Keep consistency in example for Stdin StdinLock)
- #82260 (rustc: Show ``@path`` usage in stable)
- #82316 (Fix minor mistake in LTO docs.)
- #82332 (Don't generate src link on dummy spans)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: Support argument files
Factors out the `rustc_driver` logic that handles argument files so that rustdoc supports them as well, e.g.:
rustdoc `@argfile`
This is needed to be able to generate docs for projects that already use argument files when compiling them, e.g. projects that pass a huge number of `--cfg` arguments.
The feature was stabilized for `rustc` in #66172.
Factors out the `rustc_driver` logic that handles argument files
so that rustdoc supports them as well, e.g.:
rustdoc @argfile
This is needed to be able to generate docs for projects that
already use argument files when compiling them, e.g. projects
that pass a huge number of `--cfg` arguments.
The feature was stabilized for `rustc` in #66172.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
* Search in the sysroot passed using `--sysroot` in addition to the
default sysroot.
* Search for `librustc_codegen_$name.so` in addition to
`librustc_codegen_$name-$release.so`.
Previously, only the end of pass RSS was indicated. This could easily
lead one to believe that the change in RSS from one pass to the next was
attributable to the second pass, when in fact it occurred between the
end of the first pass and the start of the second.
Also, improve alignment of columns.
Fix --pretty=expanded with --remap-path-prefix
Per https://github.com/rust-lang/rust/issues/80832, using
--pretty=expanded and --remap-path-prefix results in an ICE.
This is becasue the session source files table is stored in remapped
form, whereas --pretty-expanded looks up unremapped files. This remaps
the path prefixes before lookup.
~~There don't appear to be any existing tests for --pretty=expanded; I'll look into
adding some.~~ Never mind, found the pretty tests.
Fixes#80832
Rationale:
- `atty` is widely used in the Rust ecosystem
- We already use it (in `rustc_errors` and other places)
- We shouldn't be rolling our own TTY detector when there's a
widely-used, well-tested package that we can use
Logging goes to stderr, not stdout, so we should base our automated
detection on stderr instead of stdout.
Thanks to Ralf Jung for noticing and reporting the bug!
Per https://github.com/rust-lang/rust/issues/80832, using
--pretty=expanded and --remap-path-prefix results in an ICE.
This is becasue the session source files table is stored in remapped
form, whereas --pretty-expanded looks up unremapped files. This remaps
the path prefixes before lookup.
Always print lints from plugins, if they're available
Currently you can get a list of lints and lint groups by running `rustc
-Whelp`. This prints an additional line at the end:
```
Compiler plugins can provide additional lints and lint groups. To see a listing of these, re-run `rustc -W help` with a crate filename.
```
Clippy is such a "compiler plugin", that provides additional lints.
Running `clippy-driver -Whelp` (`rustc` wrapper) still only prints the
rustc lints with the above message at the end. But when running
`clippy-driver -Whelp main.rs`, where `main.rs` is any rust file, it
also prints Clippy lints. I don't think this is a good approach from a
UX perspective: Why is a random file necessary to print a help message?
This PR changes this behavior: Whenever a compiler callback
registers lints, it is assumed that these lints come from a plugin and
are printed without having to specify a Rust source file.
Fixesrust-lang/rust-clippy#6122
cc `@Manishearth` `@ebroto` for the Clippy changes.
Currently you can get a list of lints and lint groups by running `rustc
-Whelp`. This prints an additional line at the end:
```
Compiler plugins can provide additional lints and lint groups. To see a
listing of these, re-run `rustc -W help` with a crate filename.
```
Clippy is such a "compiler plugin", that provides additional lints.
Running `clippy-driver -Whelp` (`rustc` wrapper) still only prints the
rustc lints with the above message at the end. But when running
`clippy-driver -Whelp main.rs`, where `main.rs` is any rust file, it
also prints Clippy lints. I don't think this is a good approach from a
UX perspective: Why is a random file necessary to print a help message?
This commit changes this behavior: Whenever a compiler callback
registers lints, it is assumed that these lints come from a plugin and
are printed without having to specify a Rust source file.
cleanup: Remove `ParseSess::injected_crate_name`
Its only remaining use is in pretty-printing where the necessary information can be easily re-computed.
Allow making `RUSTC_BOOTSTRAP` conditional on the crate name
Motivation: This came up in the [Zulip stream](https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/Require.20users.20to.20confirm.20they.20know.20RUSTC_.E2.80.A6.20compiler-team.23350/near/208403962) for https://github.com/rust-lang/compiler-team/issues/350.
See also https://github.com/rust-lang/cargo/pull/6608#issuecomment-458546258; this implements https://github.com/rust-lang/cargo/issues/6627.
The goal is for this to eventually allow prohibiting setting `RUSTC_BOOTSTRAP` in build.rs (https://github.com/rust-lang/cargo/issues/7088).
## User-facing changes
- `RUSTC_BOOTSTRAP=1` still works; there is no current plan to remove this.
- Things like `RUSTC_BOOTSTRAP=0` no longer activate nightly features. In practice this shouldn't be a big deal, since `RUSTC_BOOTSTRAP` is the opposite of stable and everyone uses `RUSTC_BOOTSTRAP=1` anyway.
- `RUSTC_BOOTSTRAP=x` will enable nightly features only for crate `x`.
- `RUSTC_BOOTSTRAP=x,y` will enable nightly features only for crates `x` and `y`.
## Implementation changes
The main change is that `UnstableOptions::from_environment` now requires
an (optional) crate name. If the crate name is unknown (`None`), then the new feature is not available and you still have to use `RUSTC_BOOTSTRAP=1`. In practice this means the feature is only available for `--crate-name`, not for `#![crate_name]`; I'm interested in supporting the second but I'm not sure how.
Other major changes:
- Added `Session::is_nightly_build()`, which uses the `crate_name` of
the session
- Added `nightly_options::match_is_nightly_build`, a convenience method
for looking up `--crate-name` from CLI arguments.
`Session::is_nightly_build()`should be preferred where possible, since
it will take into account `#![crate_name]` (I think).
- Added `unstable_features` to `rustdoc::RenderOptions`
I'm not sure whether this counts as T-compiler or T-lang; _technically_ RUSTC_BOOTSTRAP is an implementation detail, but it's been used so much it seems like this counts as a language change too.
r? `@joshtriplett`
cc `@Mark-Simulacrum` `@hsivonen`
Clean up outdated `use_once_payload` pretty printer comment
While reading some parts of the pretty printer code, I noticed this old comment
which seemed out of place. The `use_once_payload` this outdated comment mentions
was removed in 2017 in 40f03a1e0d, so this
completes the work by removing the comment.
While reading some parts of the pretty printer code, I noticed this old comment
which seemed out of place. The `use_once_payload` this outdated comment mentions
was removed in 2017 in 40f03a1e0d, so this
completes the work by removing the comment.
The main change is that `UnstableOptions::from_environment` now requires
an (optional) crate name. If the crate name is unknown (`None`), then the new feature is not available and you still have to use `RUSTC_BOOTSTRAP=1`. In practice this means the feature is only available for `--crate-name`, not for `#![crate_name]`; I'm interested in supporting the second but I'm not sure how.
Other major changes:
- Added `Session::is_nightly_build()`, which uses the `crate_name` of
the session
- Added `nightly_options::match_is_nightly_build`, a convenience method
for looking up `--crate-name` from CLI arguments.
`Session::is_nightly_build()`should be preferred where possible, since
it will take into account `#![crate_name]` (I think).
- Added `unstable_features` to `rustdoc::RenderOptions`
There is a user-facing change here: things like `RUSTC_BOOTSTRAP=0` no
longer active nightly features. In practice this shouldn't be a big
deal, since `RUSTC_BOOTSTRAP` is the opposite of stable and everyone
uses `RUSTC_BOOTSTRAP=1` anyway.
- Add tests
Check against `Cheat`, not whether nightly features are allowed.
Nightly features are always allowed on the nightly channel.
- Only call `is_nightly_build()` once within a function
- Use booleans consistently for rustc_incremental
Sessions can't be passed through threads, so `read_file` couldn't take a
session. To be consistent, also take a boolean in `write_file_header`.
The log color variable is whatever the log variable is (`RUSTC_LOG`,
`RUSTDOC_LOG`, `MIRI_LOG`, etc.) + `_COLOR`. So `RUSTC_LOG_COLOR`,
`RUSTDOC_LOG_COLOR`, `MIRI_LOG_COLOR`, etc.
Thanks to @RalfJung for suggesting this! It was much easier to implement
than adding a new unstable argument, which is what I tried before.
Add cg_clif as optional codegen backend
Rustc_codegen_cranelift is an alternative codegen backend for rustc based on Cranelift. It has the potential to improve compilation times in debug mode. In my experience the compile time improvements over debug mode LLVM for a clean build are about 20-30% in most cases.
This PR adds cg_clif as optional codegen backend. By default it is only enabled for `./x.py check`. It can be enabled for `./x.py build` too by adding `cranelift` to the `rust.codegen-backends` array in `config.toml`.
MCP: https://github.com/rust-lang/compiler-team/issues/270
r? `@Mark-Simulacrum`
Preparation for a subsequent change that replaces
rustc_target::config::Config with its wrapped Target.
On its own, this commit breaks the build. I don't like making
build-breaking commits, but in this instance I believe that it
makes review easier, as the "real" changes of this PR can be
seen much more easily.
Result of running:
find compiler/ -type f -exec sed -i -e 's/target\.target\([)\.,; ]\)/target\1/g' {} \;
find compiler/ -type f -exec sed -i -e 's/target\.target$/target/g' {} \;
find compiler/ -type f -exec sed -i -e 's/target.ptr_width/target.pointer_width/g' {} \;
./x.py fmt
Codegen backend interface refactor
This moves several things away from the codegen backend to rustc_interface. There are a few behavioral changes where previously the incremental cache (incorrectly) wouldn't get finalized, but now it does. See the individual commit messages.
rustc_target: Refactor away `TargetResult`
Follow-up to https://github.com/rust-lang/rust/pull/77202.
Construction of a built-in target is always infallible now, so `TargetResult` is no longer necessary.
The second commit contains some further cleanup based on built-in target construction being infallible.
RunCompiler::new takes non-optional params, and optional
params can be set using set_*field_name* method.
finally `run` will forward all fields to `run_compiler`.
The primary motivation is to get the changes from
https://github.com/tokio-rs/tracing/pull/990. Example output:
```
$ RUSTDOC_LOG=debug rustdoc +rustc2
warning: some trace filter directives would enable traces that are disabled statically
| `debug` would enable the DEBUG level for all targets
= note: the static max level is `info`
= help: to enable DEBUG logging, remove the `max_level_info` feature
```
- Remove useless test
This was testing for an ICE when passing `RUST_LOG=rustc_middle`. I
noticed it because it started giving the tracing warning (because tests
are not run with debug-logging enabled). Since this bug seems unlikely
to re-occur, I just removed it altogether.
Use `tracing` spans to trace the entire MIR interp stack
r? @RalfJung
While being very verbose, this allows really good tracking of what's going on. While I considered schemes like the previous indenter that we had (which we could get by using the `tracing-tree` crate), this will break down horribly with things like multithreaded rustc. Instead, we can now use `RUSTC_LOG` to restrict the things being traced. You could specify a filter in a way that only shows the logging of a specific frame.
![screenshot of command line output of the new formatting](https://user-images.githubusercontent.com/332036/89291343-aa40de00-d65a-11ea-9f6c-ea06c1806327.png)
If we lower the span's level to `debug`, then in `info` level logging we'd not see the frames, but in `debug` level we would see them. The filtering rules in `tracing` are super powerful, but I'm not sure if we can specify a filter so we do see `debug` level events, but *not* the `frame` spans. The documentation at https://docs.rs/tracing-subscriber/0.2.10/tracing_subscriber/struct.EnvFilter.html makes me think that we can only turn on things, not turn off things at a more precise level.
cc @hawkw
Add option to pass a custom codegen backend from a driver
This allows the driver to pass information to the codegen backend. For example the headcrab debugger may in the future want to use cg_clif to JIT code to be injected in the debuggee. This would PR make it possible to tell cg_clif which symbol can be found at which address and to tell it to inject the JITed code into the right process.
This PR may also help with https://github.com/rust-lang/miri/pull/1540 by allowing miri to provide a codegen backend that only emits metadata and doesn't perform any codegen.
cc @nbaksalyar (headcrab)
cc @RalfJung (miri)
diagnostics: shorten paths of unique symbols
This is a step towards implementing a fix for #50310, and continuation of the discussion in [Pre-RFC: Nicer Types In Diagnostics - compiler - Rust Internals](https://internals.rust-lang.org/t/pre-rfc-nicer-types-in-diagnostics/11139). Impressed upon me from previous discussion in #21934 that an RFC for this is not needed, and I should just come up with code.
The recent improvements to `use` suggestions that I've contributed have given rise to this implementation. Contrary to previous suggestions, it's rather simple logic, and I believe it only reduces the amount of cognitive load that a developer would need when reading type errors.
-----
If a symbol name can only be imported from one place, and as long as it was not glob-imported anywhere in the current crate, we can trim its printed path to the last component.
This has wide implications on error messages with types, for example, shortening `std::vec::Vec` to just `Vec`, as long as there is no other `Vec` importable from anywhere.
`run_compiler` is used by clippy and other tools, which should not have
the trimmed paths feature enabled by default, until we see it works well
for them.
Would also be nice to rename `TimePassesCallbacks` however it's a
submodule change.
If a symbol name can only be imported from one place for a type, and
as long as it was not glob-imported anywhere in the current crate, we
can trim its printed path and print only the name.
This has wide implications on error messages with types, for example,
shortening `std::vec::Vec` to just `Vec`, as long as there is no other
`Vec` importable anywhere.
This adds a new '-Z trim-diagnostic-paths=false' option to control this
feature.
On the good path, with no diagnosis printed, we should try to avoid
issuing this query, so we need to prevent trimmed_def_paths query on
several cases.
This change also relies on a previous commit that differentiates
between `Debug` and `Display` on various rustc types, where the latter
is trimmed and presented to the user and the former is not.