I was surprised to find that running with `-Zparse-only` only parses the
crate root file. Other files aren't parsed because that happens later
during expansion.
This commit renames the option and updates the help message to make this
clearer.
Don't allow `-Zunstable-options` to take a value
Passing an explicit boolean value (`-Zunstable-options=on`, `off` etc.) sometimes appears to work, but actually puts the compiler into an unintended state where unstable _options_ are still forbidden, but unstable values of _some_ stable options are allowed.
This is a result of `-Zunstable-options` being checked in multiple different places, in slightly different ways. Fixing the checks in `config::nightly_options` to understand boolean values would be non-trivial, so for now it's easier to make things consistent by forbidding values in the `-Z` parser.
---
There were a few uses of this in tests, which happened to work because they were tests of unstable values.
Merge `-Zhir-stats` into `-Zinput-stats`
Currently `-Z hir-stats` prints the size and count of various kinds of nodes, and the total size of all the nodes it counted, but not the total count of nodes. So, before this PR:
```
$ git clone https://github.com/BurntSushi/ripgrep
$ cd ripgrep
$ cargo +nightly rustc -- -Z hir-stats
ast-stats-1 PRE EXPANSION AST STATS
ast-stats-1 Name Accumulated Size Count Item Size
ast-stats-1 ----------------------------------------------------------------
ast-stats-1 ...
ast-stats-1 ----------------------------------------------------------------
ast-stats-1 Total 93_576
ast-stats-1
ast-stats-2 POST EXPANSION AST STATS
ast-stats-2 Name Accumulated Size Count Item Size
ast-stats-2 ----------------------------------------------------------------
ast-stats-2 ...
ast-stats-2 ----------------------------------------------------------------
ast-stats-2 Total 2_430_648
ast-stats-2
hir-stats HIR STATS
hir-stats Name Accumulated Size Count Item Size
hir-stats ----------------------------------------------------------------
hir-stats ...
hir-stats ----------------------------------------------------------------
hir-stats Total 3_678_512
hir-stats
```
For consistency, this PR adds a total for the count as well:
```
$ cargo +stage1 rustc -- -Z hir-stats
ast-stats-1 PRE EXPANSION AST STATS
ast-stats-1 Name Accumulated Size Count Item Size
ast-stats-1 ----------------------------------------------------------------
ast-stats-1 ...
ast-stats-1 ----------------------------------------------------------------
ast-stats-1 Total 93_576 1_877
ast-stats-1
ast-stats-2 POST EXPANSION AST STATS
ast-stats-2 Name Accumulated Size Count Item Size
ast-stats-2 ----------------------------------------------------------------
ast-stats-2 ...
ast-stats-2 ----------------------------------------------------------------
ast-stats-2 Total 2_430_648 48_625
ast-stats-2
hir-stats HIR STATS
hir-stats Name Accumulated Size Count Item Size
hir-stats ----------------------------------------------------------------
hir-stats ...
hir-stats ----------------------------------------------------------------
hir-stats Total 3_678_512 73_418
hir-stats
```
I wasn't sure if I was supposed to update `tests/ui/stats/hir-stats.stderr` to reflect this. I ran it locally, thinking it would fail, but it didn't:
```
$ ./x test tests/ui/stats
...
running 2 tests
i.
test result: ok. 1 passed; 0 failed; 1 ignored; 0 measured; 17949 filtered out
```
Also: is there a reason `-Z hir-stats` and `-Z input-stats` both exist? The former seems like it should completely supercede the latter. But strangely, the two give very different numbers for node counts:
```
$ cargo +nightly rustc -- -Z input-stats
...
Lines of code: 483
Pre-expansion node count: 2386
Post-expansion node count: 63844
```
That's a 30% difference in this case. Is it intentional that these numbers are so different? I see comments for both saying that they are merely approximations and should not be expected to be correct:
bd0826a452/compiler/rustc_ast_passes/src/node_count.rs (L1)bd0826a452/compiler/rustc_passes/src/hir_stats.rs (L1-L3)
Passing an explicit boolean value (`on`, `off` etc.) appears to work, but
actually puts the compiler into an unintended state where unstable _options_
are still forbidden, but unstable values of _some_ stable options are allowed.
Over in Zed we've noticed that loading crates for a large-ish workspace can take almost 200ms. We've pinned it down to how rustc searches for paths, as it performs a linear search over the list of candidate paths. In our case the candidate list had about 20k entries which we had to iterate over for each dependency being loaded.
This commit introduces a simple FilesIndex that's just a sorted Vec under the hood. Since crates are looked up by both prefix and suffix, we perform a range search on said Vec (which constraints the search space based on prefix) and follow up with a linear scan of entries with matching suffixes.
FilesIndex is also pre-filtered before any queries are performed using available target information; query prefixes/sufixes are based on the target we are compiling for, so we can remove entries that can never match up front.
Overall, this commit brings down build time for us in dev scenarios by about 6%.
100ms might not seem like much, but this is a constant cost that each of our workspace crates has to pay, even when said crate is miniscule.
Add a default implementation for CodegenBackend::link
As a side effect this should add raw-dylib support to cg_gcc as the default ArchiveBuilderBuilder that is used implements create_dll_import_lib. I haven't tested if the raw-dylib support actually works however.
require const_impl_trait gate for all conditional and trait const calls
Alternative to https://github.com/rust-lang/rust/pull/132786.
`@compiler-errors` this is basically what I meant with my proposals. I found it's easier to express this in code than English. ;)
r? `@compiler-errors`
Simplify the internal API for declaring command-line options
The internal APIs for declaring command-line options are old, and intimidatingly complex. This PR replaces them with a single function that takes explicit `stability` and `kind` arguments, making it easier to see how each option is handled, and whether it is treated as stable or unstable.
We also don't appear to have any tests for the output of `rustc --help` and similar, so I've added a run-make test to verify that this PR doesn't change any output. (There is already a similar run-make test for rustdoc's help output.)
---
The librustdoc changes are simply adjusting to updated compiler APIs; no functional change intended.
---
A side-effect of these changes is that rustfmt can once again format the entirety of these option declaration lists, which it was not doing before.
Set "symbol name" in raw-dylib import libraries to the decorated name
`windows-rs` received a bug report that mixing raw-dylib generated and the Windows SDK import libraries was causing linker failures: <https://github.com/microsoft/windows-rs/issues/3285>
The root cause turned out to be #124958, that is we are not including the decorated name in the import library and so the import name type is also not being correctly set.
This change modifies the generation of import libraries to set the "symbol name" to the fully decorated name and correctly marks the import as being data vs function.
Note that this also required some changes to how the symbol is named within Rust: for MSVC we now need to use the decorated name but for MinGW we still need to use partially decorated (or undecorated) name.
Fixes#124958
Passing i686 MSVC and MinGW build: <https://github.com/rust-lang/rust/actions/runs/11000433888?pr=130586>
r? `@ChrisDenton`
Remove the `wasm32-wasi` target from rustc
This commit is the final step in the journey of renaming the historical `wasm32-wasi` target in the Rust compiler to `wasm32-wasip1`. Various steps in this journey so far have been:
* 2023-04-03: rust-lang/compiler-team#607 - initial proposal for this rename
* 2024-11-27: rust-lang/compiler-team#695 - amended schedule/procedure for rename
* 2024-01-29: rust-lang/rust#120468 - initial introduction of `wasm32-wasip1`
* 2024-06-18: rust-lang/rust#126662 - warn on usage of `wasm32-wasi`
* 2024-11-08: this PR - remove the `wasm32-wasi` target
The full transition schedule is in [this comment][comment] and is summarized with:
* 2024-05-02: Rust 1.78 released with `wasm32-wasip1` target
* 2024-09-05: Rust 1.81 released warning on usage of `wasm32-wasi`
* 2025-01-09: Rust 1.84 to be released without the `wasm32-wasi` target
This means that support on stable for the replacement target of `wasm32-wasip1` has currently been available for 6 months. Users have already seen warnings on stable for 2 months about usage of `wasm32-wasi` and stable users have another 2 months of warnings before the target is removed from stable.
This commit is intended to be the final step in this transition so the source tree should no longer mention `wasm32-wasi` except in historical reference to the older name of the `wasm32-wasip1` target.
[comment]: https://github.com/rust-lang/rust/pull/120468#issuecomment-1977878747
rustc_codegen_llvm: Add a new 'pc' option to branch-protection
Add a new 'pc' option to -Z branch-protection for aarch64 that enables the use of PC as a diversifier in PAC branch protection code.
When the pauth-lr target feature is enabled in combination with -Z branch-protection=pac-ret,pc, the new 9.5-a instructions (pacibsppc, retaasppc, etc) will be generated.
mark some target features as 'forbidden' so they cannot be (un)set with -Ctarget-feature
The context for this is https://github.com/rust-lang/rust/issues/116344: some target features change the way floats are passed between functions. Changing those target features is unsound as code compiled for the same target may now use different ABIs.
So this introduces a new concept of "forbidden" target features (on top of the existing "stable " and "unstable" categories), and makes it a hard error to (un)set such a target feature. For now, the x86 and ARM feature `soft-float` is on that list. We'll have to make some effort to collect more relevant features, and similar features from other targets, but that can happen after the basic infrastructure for this landed. (These features are being collected in https://github.com/rust-lang/rust/issues/131799.)
I've made this a warning for now to give people some time to speak up if this would break something.
MCP: https://github.com/rust-lang/compiler-team/issues/780
This commit is the final step in the journey of renaming the historical
`wasm32-wasi` target in the Rust compiler to `wasm32-wasip1`. Various
steps in this journey so far have been:
* 2023-04-03: rust-lang/compiler-team#607 - initial proposal for this rename
* 2024-11-27: rust-lang/compiler-team#695 - amended schedule/procedure for rename
* 2024-01-29: rust-lang/rust#120468 - initial introduction of `wasm32-wasip1`
* 2024-06-18: rust-lang/rust#126662 - warn on usage of `wasm32-wasi`
* 2024-11-08: this PR - remove the `wasm32-wasi` target
The full transition schedule is in [this comment][comment] and is
summarized with:
* 2024-05-02: Rust 1.78 released with `wasm32-wasip1` target
* 2024-09-05: Rust 1.81 released warning on usage of `wasm32-wasi`
* 2025-01-09: Rust 1.84 to be released without the `wasm32-wasi` target
This means that support on stable for the replacement target of
`wasm32-wasip1` has currently been available for 6 months. Users have
already seen warnings on stable for 2 months about usage of
`wasm32-wasi` and stable users have another 2 months of warnings before
the target is removed from stable.
This commit is intended to be the final step in this transition so the
source tree should no longer mention `wasm32-wasi` except in historical
reference to the older name of the `wasm32-wasip1` target.
[comment]: https://github.com/rust-lang/rust/pull/120468#issuecomment-1977878747
make codegen help output more consistent
The output of `rustc -C help` generally has one option per line. There was one exception because of a (presumably) forgotten line continuation escape.
Add a new 'pc' option to -Z branch-protection for aarch64 that
enables the use of PC as a diversifier in PAC branch protection code.
When the pauth-lr target feature is enabled in combination
with -Z branch-protection=pac-ret,pc, the new 9.5-a instructions
(pacibsppc, retaasppc, etc) will be generated.
Depend on rustc_abi in compiler crates that use it indirectly but have
not yet taken on that dependency, and are not entangled in my other PRs.
This leaves an "excise rustc_target" step after the dust settles.
Implement RFC3695 Allow boolean literals as cfg predicates
This PR implements https://github.com/rust-lang/rfcs/pull/3695: allow boolean literals as cfg predicates, i.e. `cfg(true)` and `cfg(false)`.
r? `@nnethercote` *(or anyone with parser knowledge)*
cc `@clubby789`
Add unstable support for outputting file checksums for use in cargo
Adds an unstable option that appends file checksums and expected lengths to the end of the dep-info file such that `cargo` can read and use these values as an alternative to file mtimes.
This PR powers the changes made in this cargo PR https://github.com/rust-lang/cargo/pull/14137
Here's the tracking issue for the cargo feature https://github.com/rust-lang/cargo/issues/14136.
Fix#128930: Print documentation of CLI options missing their arg
Fix#128930. Failing to give an argument to CLI options which require it now prints something like:
```
$ rustc --print
error: Argument to option 'print' missing
Usage:
--print [crate-name|file-names|sysroot|target-libdir|cfg|check-cfg|calling-conventions|target-list|target-cpus|target-features|relocation-models|code-models|tls-models|target-spec-json|all-target-specs-json|native-static-libs|stack-protector-strategies|link-args|deployment-target]
Compiler information to print on stdout
```
deprecate -Csoft-float because it is unsound (and not fixable)
See https://github.com/rust-lang/rust/issues/129893 for details. The general sentiment there seems to be that this flag has no use and sound alternatives exist, so let's add this warning and see if anyone out there disagrees.
Also show a different warning on targets where it does nothing (as documented since https://github.com/rust-lang/rust/pull/36261): it seems to correspond to `-mfloat-abi` in GCC/clang, which is an ARM-specific option. To be really sure it does nothing, only forward the flag to LLVM for eabihf targets. This should not change behavior but makes me sleep better ;)
Add -Z small-data-threshold
This flag allows specifying the threshold size above which LLVM should not consider placing small objects in a `.sdata` or `.sbss` section.
Support is indicated in the target options via the
small-data-threshold-support target option, which can indicate either an
LLVM argument or an LLVM module flag. To avoid duplicate specifications
in a large number of targets, the default value for support is
DefaultForArch, which is translated to a concrete value according to the
target's architecture.
This flag allows specifying the threshold size above which LLVM should
not consider placing small objects in a .sdata or .sbss section.
Support is indicated in the target options via the
small-data-threshold-support target option, which can indicate either an
LLVM argument or an LLVM module flag. To avoid duplicate specifications
in a large number of targets, the default value for support is
DefaultForArch, which is translated to a concrete value according to the
target's architecture.
We want to allow setting this on the CLI, override it only in MIR
passes, and disable it altogether in mir-opt tests.
The default value is "only for NLL MIR dumps", which is considered off
for all intents and purposes, except for `rustc_borrowck` when an NLL
MIR dump is requested.
rustc: Simplify getting sysroot library directory
It was very non-obvious that `sess.target_tlib_path`, `make_target_lib_path(...)`, and `sess.target_filesearch(...).search_paths()` result in the same sysroot library directory paths.
They are however, indeed the same, because `sess.target_tlib_path` is initialized to `make_target_lib_path(...)` on `Session` creation, and they are used interchangeably.
There are still some redundant calls to `make_target_lib_path` and other inconsistent ways to obtain sysroot directories, but fixing that requires some behavior changes, while this PR is a pure refactoring.
Some places in the compiler even disagree on the number of sysroots - 1 (explicit `--sysroot` *or* default sysroot), 2 (explicit `--sysroot` *and* default sysroot), or an unclear number of `sysroot_candidates` every of which is considered.
The logic currently using `sess.target_tlib_path` or equivalents assumes one sysroot.
Unconditionally allow shadow call-stack sanitizer for AArch64
It is possible to do so whenever `-Z fixed-x18` is applied.
cc ``@Darksonn`` for context
The reasoning is that, as soon as reservation on `x18` is forced through the flag `fixed-x18`, on AArch64 the option to instrument with [Shadow Call Stack sanitizer](https://clang.llvm.org/docs/ShadowCallStack.html) is then applicable regardless of the target configuration.
At the every least, we would like to relax the restriction on specifically `aarch64-unknonw-none`. For this option, we can include a documentation change saying that users of compiled objects need to ensure that they are linked to runtime with Shadow Call Stack instrumentation support.
Related: #121972
Use more slice patterns inside the compiler
Nothing super noteworthy. Just replacing the common 'fragile' pattern of "length check followed by indexing or unwrap" with slice patterns for legibility and 'robustness'.
r? ghost
Gate the type length limit check behind a nightly flag
Effectively disables the type length limit by introducing a `-Zenforce-type-length-limit` which defaults to **`false`**, since making the length limit actually be enforced ended up having a worse fallout than expected. We still keep the code around, but the type length limit attr is now a noop (except for its usage in some diagnostics code?).
r? `@lcnr` -- up to you to decide what team consensus we need here since this reverses an FCP decision.
Reopens#125460 (if we decide to reopen it or keep it closed)
Effectively reverses the decision FCP'd in #125507Closes#127346
use "bootstrap" instead of "rustbuild" in comments and docs
Let's stick with the single name "bootstrap" to refer to the bootstrap project to avoid confusion. This should make it clearer, especially for new contributors.
Ignore allocation bytes in some mir-opt tests
This adds `rustc -Zdump-mir-exclude-alloc-bytes` to skip writing allocation bytes in MIR dumps, and applies it to tests that were failing on s390x due to its big-endian byte order.
Fixes#126261
Since this codegen flag now only controls LLVM-generated comments rather than
all assembly comments, make the name more accurate (and also match Clang).
In 126578 we ended up with more binary size increases than expected.
This change attempts to avoid inlining large things into small things, to avoid that kind of increase, in cases when top-down inlining will still be able to do that inlining later.
patchable-function-entry: Add unstable compiler flag and attribute
Tracking issue: #123115
Add the -Z patchable-function-entry compiler flag and the #[patchable_function_entry(prefix_nops = m, entry_nops = n)] attribute.
Rebased and adjusted the canditate implementation to match changes in the RFC.
`-Z patchable-function-entry` works like `-fpatchable-function-entry`
on clang/gcc. The arguments are total nop count and function offset.
See MCP rust-lang/compiler-team#704
Deprecate no-op codegen option `-Cinline-threshold=...`
This deprecates `-Cinline-threshold` since using it has no effect. This has been the case since the new LLVM pass manager started being used, more than 2 years ago.
Recommend using `-Cllvm-args=--inline-threshold=...` instead.
Closes#89742 which is E-help-wanted.
Added an associated `const THIS_IMPLEMENTATION_HAS_BEEN_TRIPLE_CHECKED`
to the `StableOrd` trait to ensure that implementors carefully consider
whether the trait's contract is upheld, as incorrect implementations can
cause miscompilations.
Most modules have such a blank line, but some don't. Inserting the blank
line makes it clearer that the `//!` comments are describing the entire
module, rather than the `use` declaration(s) that immediately follows.
This commit is a continuation of the work originally proposed in
rust-lang/compiler-team#607 and later amended in
rust-lang/compiler-team#695. The end goal is to rename `wasm32-wasi` to
`wasm32-wasip1` to reflect WASI's development and distinguish the
preexisting target from the `wasm32-wasip2` target that WASI is now
developing. Work for this transition began in #120468 which landed in
Rust 1.78 which became stable on 2024-05-02.
This implements the next phase of the transition plan to warn on usage
of `wasm32-wasi`. This is intended to help alert users that a removal is
pending and all release channels have the replacement available as well.
This will reach stable on 2024-09-05. The next stage of the plan is to
remove the `wasm32-wasi` target some time in October 2024 which means
that the removal will reach stable on 2025-01-09. For reference a full
schedule of this transition is listed [here].
Currently this implementation is a simple unconditional warning whenever
`rustc --target wasm32-wasi` is invoked. As-implemented there's no way
to turn off the warning other than to switch to the `wasm32-wasip1`
target.
[here]: https://github.com/rust-lang/rust/pull/120468#issuecomment-1977878747
Replace all `&DiagCtxt` with a `DiagCtxtHandle<'_>` wrapper type
r? `@davidtwco`
This paves the way for tracking more state (e.g. error tainting) in the diagnostic context handle
Basically I will add a field to the `DiagCtxtHandle` that refers back to the `InferCtxt`'s (and others) `Option<ErrorHandled>`, allowing us to immediately taint these contexts when emitting an error and not needing manual tainting anymore (which is easy to forget and we don't do in general anyway)
When set, this flag skips the code that normally extracts coverage spans from
MIR statements and terminators. That sometimes makes it easier to debug branch
coverage and MC/DC coverage, because the coverage output is less noisy.
For internal debugging only. If other code changes would make it hard to keep
supporting this flag, remove it.
This deprecates `-Cinline-threshold` since using it has no effect. This
has been the case since the new LLVM pass manager started being used,
more than 2 years ago.
We already do this for a number of crates, e.g. `rustc_middle`,
`rustc_span`, `rustc_metadata`, `rustc_span`, `rustc_errors`.
For the ones we don't, in many cases the attributes are a mess.
- There is no consistency about order of attribute kinds (e.g.
`allow`/`deny`/`feature`).
- Within attribute kind groups (e.g. the `feature` attributes),
sometimes the order is alphabetical, and sometimes there is no
particular order.
- Sometimes the attributes of a particular kind aren't even grouped
all together, e.g. there might be a `feature`, then an `allow`, then
another `feature`.
This commit extends the existing sorting to all compiler crates,
increasing consistency. If any new attribute line is added there is now
only one place it can go -- no need for arbitrary decisions.
Exceptions:
- `rustc_log`, `rustc_next_trait_solver` and `rustc_type_ir_macros`,
because they have no crate attributes.
- `rustc_codegen_gcc`, because it's quasi-external to rustc (e.g. it's
ignored in `rustfmt.toml`).
Add `--print=check-cfg` to get the expected configs
This PR adds a new `--print` variant `check-cfg` to get the expected configs.
Details and rational can be found on the MCP: https://github.com/rust-lang/compiler-team/issues/743
``@rustbot`` label +F-check-cfg +S-waiting-on-MCP
r? ``@petrochenkov``
Remove many `#[macro_use] extern crate foo` items
This requires the addition of more `use` items, which often make the code more verbose. But they also make the code easier to read, because `#[macro_use]` obscures where macros are defined.
r? `@fee1-dead`
