Avoid no-op unlink+link dances in incr comp
Incremental compilation scales quite poorly with the number of CGUs. This PR improves one reason for that.
The incr comp process hard-links all the files from an old session into a new one, then it runs the backend, which may just hard-link the new session files into the output directory. Then codegen hard-links all the output files back to the new session directory.
This PR (perhaps unimaginatively) fixes the silliness that ensues in the last step. The old `link_or_copy` implementation would be passed pairs of paths which are already the same inode, then it would blindly delete the destination and re-create the hard-link that it just deleted. This PR lets us skip both those operations. We don't skip the other two hard-links.
`cargo +stage1 b && touch crates/core/main.rs && strace -cfw -elink,linkat,unlink,unlinkat cargo +stage1 b` before and then after on `ripgrep-13.0.0`:
```
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
52.56 0.024950 25 978 485 unlink
34.38 0.016318 22 727 linkat
13.06 0.006200 24 249 unlinkat
------ ----------- ----------- --------- --------- ----------------
100.00 0.047467 24 1954 485 total
```
```
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
42.83 0.014521 57 252 unlink
38.41 0.013021 26 486 linkat
18.77 0.006362 25 249 unlinkat
------ ----------- ----------- --------- --------- ----------------
100.00 0.033904 34 987 total
```
This reduces the number of hard-links that are causing perf troubles, noted in https://github.com/rust-lang/rust/issues/64291 and https://github.com/rust-lang/rust/issues/137560
Rollup of 8 pull requests
Successful merges:
- #138435 (Add support for postfix yield expressions)
- #138685 (Use `Option<Ident>` for lowered param names.)
- #138700 (Suggest `-Whelp` when pass `--print lints` to rustc)
- #138727 (Do not rely on `type_var_origin` in `OrphanCheckErr::NonLocalInputType`)
- #138729 (Clean up `FnCtxt::resolve_coroutine_interiors`)
- #138731 (coverage: Add LLVM plumbing for expansion regions)
- #138732 (Use `def_path_str` for def id arg in `UnsupportedOpInfo`)
- #138735 (Remove `llvm` and `llvms` triagebot ping aliases for `icebreakers-llvm` ping group)
r? `@ghost`
`@rustbot` modify labels: rollup
expand: Leave traces when expanding `cfg_attr` attributes
Currently `cfg_trace` just disappears during expansion, but after this PR `#[cfg_attr(some tokens)]` will leave a `#[cfg_attr_trace(some tokens)]` attribute instead of itself in AST after expansion (the new attribute is built-in and inert, its inner tokens are the same as in the original attribute).
This trace attribute can then be used by lints or other diagnostics, #133823 has some examples.
Tokens in these trace attributes are set to an empty token stream, so the traces are non-existent for proc macros and cannot affect any user-observable behavior.
This is also a weakness, because if a proc macro processes some code with the trace attributes, they will be lost, so the traces are best effort rather than precise.
The next step is to do the same thing with `cfg` attributes (`#[cfg(TRUE)]` currently remains in both AST and tokens after expanding, it should be replaced with a trace instead).
The idea belongs to `@estebank.`
Remove `llvm` and `llvms` triagebot ping aliases for `icebreakers-llvm` ping group
Because it's way too easy to confuse LLVM Icebreakers ping group versus trying to ping WG-llvm.
And AFAIK, icebreakers-llvm isn't really used in a good while.
I also fixed the rustc-dev-guide docs about ``@rustbot` ping llvm` (and changed that to the raw ping group name ``@rustbot` icebreakers-llvm`) because it's very confusing.
Previously discussed in [#t-compiler/wg-llvm > Ping group renaming](https://rust-lang.zulipchat.com/#narrow/channel/187780-t-compiler.2Fwg-llvm/topic/Ping.20group.20renaming/with/453005029).
FYI `@rust-lang/wg-llvm`
FYI `@RalfJung` (since you asked in https://github.com/rust-lang/rust/pull/138120#issuecomment-2710466874)
r? `@nikic` (or wg-llvm)
Use `Option<Ident>` for lowered param names.
Parameter patterns are lowered to an `Ident` by `lower_fn_params_to_names`, which is used when lowering bare function types, trait methods, and foreign functions. Currently, there are two exceptional cases where the lowered param can become an empty `Ident`.
- If the incoming pattern is an empty `Ident`. This occurs if the parameter is anonymous, e.g. in a bare function type.
- If the incoming pattern is neither an ident nor an underscore. Any such parameter will have triggered a compile error (hence the `span_delayed_bug`), but lowering still occurs.
This commit replaces these empty `Ident` results with `None`, which eliminates a number of `kw::Empty` uses, and makes it impossible to fail to check for these exceptional cases.
Note: the `FIXME` comment in `is_unwrap_or_empty_symbol` is removed. It actually should have been removed in #138482, the precursor to this PR. That PR changed the lowering of wild patterns to `_` symbols instead of empty symbols, which made the mentioned underscore check load-bearing.
r? ``@compiler-errors``
Add support for postfix yield expressions
We've been having a discussion about whether we want postfix yield, or want to stick with prefix yield, or have both. I figured it's easy enough to support both for now and let us play around with them while the feature is still experimental.
This PR treats `yield x` and `x.yield` as semantically equivalent. There was a suggestion to make `yield x` have a `()` type (so it only works in coroutines with `Resume = ()`. I think that'd be worth trying, either in a later PR, or before this one merges, depending on people's opinions.
#43122
Consider fields to be inhabited if they are unstable
Fixes#133885 with a simple heuristic
r? Nadrieril
Not totally certain if this needs T-lang approval or a crater run.
Represent diagnostic side effects as dep nodes
This changes diagnostic to be tracked as a special dep node (`SideEffect`) instead of having a list of side effects associated with each dep node. `SideEffect` is always red and when forced, it emits the diagnostic and marks itself green. Each emitted diagnostic generates a new `SideEffect` with an unique dep node index.
Some implications of this:
- Diagnostic may now be emitted more than once as they can be emitted once when the `SideEffect` gets marked green and again if the task it depends on needs to be re-executed due to another node being red. It relies on deduplicating of diagnostics to avoid that.
- Anon tasks which emits diagnostics will no longer *incorrectly* be merged with other anon tasks.
- Reusing a CGU will now emit diagnostics from the task generating it.
Remove existing AFIDT implementation
This experiment will need to be reworked differently; I don't think we'll be going with the `dyn* Future` approach that is currently implemented.
r? oli-obk
Fixes#136286Fixes#137706Fixes#137895
Tracking:
* #133119
Revert: Add *_value methods to proc_macro lib
This reverts https://github.com/rust-lang/rust/pull/136355. That PR caused unexpected breakage:
- the rustc-dev component can no longer be loaded by cargo, which impacts Miri and clippy and likely others
- rustc_lexer can no longer be published to crates.io, which impacts RA
See https://github.com/rust-lang/rust/issues/138647 for context.
Cc `@GuillaumeGomez` `@Amanieu`
coverage: Don't store a body span in `FunctionCoverageInfo`
We aren't using this body span for anything truly essential, and having it around will be awkward when we eventually start to support expansion regions, since they aren't necessarily within the main body.
Remove double nesting in post-merge workflow
See [this](https://github.com/rust-lang/rust/pull/138630#issuecomment-2732224491) :)
Can be tested with:
```bash
#!/bin/bash
PARENT_COMMIT=493c38ba371929579fe136df26eccd9516347c7a
SHA=259fdb521200c9abba547302fc2c826479ef26b2
printf "<details>\n<summary>What is this?</summary>\n" >> output.log
printf "This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.\n" >> output.log
printf "</details>\n\n" >> output.log
cargo run --release post-merge-report ${PARENT_COMMIT} ${SHA} >> output.log
```
I think that it's better to leave the notice in CI, to avoid generating it in citool, which can also be executed locally.
r? `@marcoieni`
Temporarily disable Fuchsia test job to unblock queue
See <https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/fuchsia.20failure/with/506637259> for efforts to fix the test job.
This PR temporarily disables the Fuchsia test job to unblock the queue, so that neither the Fuchsia maintainers nor T-infra maintainers should feel pressured to fix the job ASAP.
Please feel free to re-enable once the test job is fixed.
FYI `@erickt` since you or other Fuchsia maintainers will need to revert this change to merge Fuchsia test job fixes in the future.
r? infra-ci
uefi: fs: Implement exists
Also adds the initial file abstractions.
The file opening algorithm is inspired from UEFI shell. It starts by classifying if the Path is Shell mapping, text representation of device path protocol, or a relative path and converts into an absolute text representation of device path protocol.
After that, it queries all handles supporting
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL and opens the volume that matches the device path protocol prefix (similar to Windows drive). After that, it opens the file in the volume using the remaining pat.
It also introduces OwnedDevicePath and BorrowedDevicePath abstractions to allow working with the base UEFI and Shell device paths efficiently.
DevicePath in UEFI behaves like an a group of nodes laied out in the memory contiguously and thus can be modeled using iterators.
This is an effort to break the original PR (https://github.com/rust-lang/rust/pull/129700) into much smaller chunks for faster upstreaming.
Rollup of 7 pull requests
Successful merges:
- #138384 (Move `hir::Item::ident` into `hir::ItemKind`.)
- #138508 (Clarify "owned data" in E0515.md)
- #138531 (Store test diffs in job summaries and improve analysis formatting)
- #138533 (Only use `DIST_TRY_BUILD` for try jobs that were not selected explicitly)
- #138556 (Fix ICE: attempted to remap an already remapped filename)
- #138608 (rustc_target: Add target feature constraints for LoongArch)
- #138619 (Flatten `if`s in `rustc_codegen_ssa`)
r? `@ghost`
`@rustbot` modify labels: rollup
Mangle rustc_std_internal_symbols functions
This reduces the risk of issues when using a staticlib or rust dylib compiled with a different rustc version in a rust program. Currently this will either (in the case of staticlib) cause a linker error due to duplicate symbol definitions, or (in the case of rust dylibs) cause rustc_std_internal_symbols functions to be silently overridden. As rust gets more commonly used inside the implementation of libraries consumed with a C interface (like Spidermonkey, Ruby YJIT (curently has to do partial linking of all rust code to hide all symbols not part of the C api), the Rusticl OpenCL implementation in mesa) this is becoming much more of an issue. With this PR the only symbols remaining with an unmangled name are rust_eh_personality (LLVM doesn't allow renaming it) and `__rust_no_alloc_shim_is_unstable`.
Helps mitigate https://github.com/rust-lang/rust/issues/104707
try-job: aarch64-gnu-debug
try-job: aarch64-apple
try-job: x86_64-apple-1
try-job: x86_64-mingw-1
try-job: i686-mingw-1
try-job: x86_64-msvc-1
try-job: i686-msvc-1
try-job: test-various
try-job: armhf-gnu
Fix ICE: attempted to remap an already remapped filename
This commit fixes an internal compiler error (ICE) that occurs when
rustdoc attempts to process macros with a remapped filename. The issue
arose during macro expansion when the `--remap-path-prefix` option was
used.
Instead of passing remapped filenames through, which would trigger the
"attempted to remap an already remapped filename" panic, we now
extract the original local path from remapped filenames before
processing them.
A test case has been added to verify this behavior.
Fixes#138520
Only use `DIST_TRY_BUILD` for try jobs that were not selected explicitly
Some CI jobs (x64 Linux, ARM64 Linux and x64 MSVC) use the `opt-dist` tool to build an optimized toolchain using PGO and BOLT. When performing a default try build for x64 Linux, in most cases we want to run perf. on that artifact. To reduce the latency of this common use-case, `opt-dist` skips building several components not needed for perf., and it also skips running post-optimization tests, when it detects that the job is executed as a try job (not a merge/auto job).
This is useful, but it also means that if you *want* to run the tests, you had to go to `jobs.yml` and manually comment this environment variable, create a WIP commit, do a try build, and then remove the WIP commit, which is annoying (in the similar way that modifying what gets run in try builds was annoying before we had the `try-job` annotations).
I thought that we could introduce some additional PR description marker like `try-job-run-tests`, but it's hard to discover that such things exist.
Instead, I think that there's a much simpler heuristic for determining whether `DIST_TRY_BUILD` should be used (that I implemented in this PR):
- If you do just ``@bors` try`, without any custom try jobs selected, `DIST_TRY_BUILD` will be activated, to finish the build as fast as possible.
- If you specify any custom try jobs, you are most likely doing experiments and you want to see if tests pass and everything builds as it should. The `DIST_TRY_BUILD` variable will thus *not* be set in this case.
In this way, if you want to run dist tests, you can just add the `try-job: dist-x86_64-linux` line to the PR description, and you don't need to create any WIP commits.
r? `@marcoieni`
Store test diffs in job summaries and improve analysis formatting
This PR stores the test diffs that we already have in the post-merge workflow also into individual job summaries. This makes it easier to compare test (and later also other) diffs per job, which will be especially useful for try jobs, so that we can actually see the test diffs *before* we merge a given PR.
As a drive-by, I also made a bunch of cleanups in `citool` and in the formatting of the summary and post-merge analyses. These changes are split into self-contained commits.
The analysis can be tested locally with the following command:
```bash
$ curl https://ci-artifacts.rust-lang.org/rustc-builds/<current-sha>/metrics-<job-name>.json > metrics.json
$ cargo run --manifest-path src/ci/citool/Cargo.toml postprocess-metrics metrics.json --job-name <job-name> --parent <parent-sha> > out.md
```
For example, for [this PR](https://github.com/rust-lang/rust/pull/138523):
```bash
$ curl https://ci-artifacts.rust-lang.org/rustc-builds/282865097d138c7f0f7a7566db5b761312dd145c/metrics-aarch64-gnu.json > metrics.json
$ cargo run --manifest-path src/ci/citool/Cargo.toml postprocess-metrics metrics.json --job-name aarch64-gnu --parent d9e5539a39192028a7b15ae596a8685017faecee > out.md
```
Best reviewed commit by commit.
r? `@marcoieni`
try-job: aarch64-gnu
try-job: dist-x86_64-linux
Clarify "owned data" in E0515.md
This clarifies the explanation of why this is not allowed and also what to do instead.
Fixes#62071
PS There was suggestion of adding a link to the book. I did not yet do that, but if desired that could be added.
Move `hir::Item::ident` into `hir::ItemKind`.
`hir::Item` has an `ident` field.
- It's always non-empty for these item kinds: `ExternCrate`, `Static`, `Const`, `Fn`, `Macro`, `Mod`, `TyAlias`, `Enum`, `Struct`, `Union`, Trait`, TraitAalis`.
- It's always empty for these item kinds: `ForeignMod`, `GlobalAsm`, `Impl`.
- For `Use`, it is non-empty for `UseKind::Single` and empty for `UseKind::{Glob,ListStem}`.
All of this is quite non-obvious; the only documentation is a single comment saying "The name might be a dummy name in case of anonymous items". Some sites that handle items check for an empty ident, some don't. This is a very C-like way of doing things, but this is Rust, we have sum types, we can do this properly and never forget to check for the exceptional case and never YOLO possibly empty identifiers (or possibly dummy spans) around and hope that things will work out.
This is step towards `kw::Empty` elimination (#137978).
r? `@fmease`
change config.toml to bootstrap.toml
Currently, both Bootstrap and Cargo uses same name as their configuration file, which can be confusing. This PR is based on a discussion to rename `config.toml` to `bootstrap.toml` for Bootstrap. Closes: https://github.com/rust-lang/rust/issues/126875.
I have split the PR into atomic commits to make it easier to review. Once the changes are finalized, I will squash them. I am particularly concerned about the changes made to modules that are not part of Bootstrap. How should we handle those changes? Should we ping the respective maintainers?
Install licenses into `share/doc/rust/licenses`
This changes the path from "licences" to "licenses" for consistency
across the repo, including the usage directly around this line. This is
a US/UK spelling difference, but I believe the US spelling is also more
common in open source in general.
Emit function declarations for functions with `#[linkage="extern_weak"]`
Currently, when declaring an extern weak function in Rust, we use the following syntax:
```rust
unsafe extern "C" {
#[linkage = "extern_weak"]
static FOO: Option<unsafe extern "C" fn() -> ()>;
}
```
This allows runtime-checking the extern weak symbol through the Option.
When emitting LLVM-IR, the Rust compiler currently emits this static as an i8, and a pointer that is initialized with the value of the global i8 and represents the nullabilty e.g.
```
`@FOO` = extern_weak global i8
`@_rust_extern_with_linkage_FOO` = internal global ptr `@FOO`
```
This approach does not work well with CFI, where we need to attach CFI metadata to a concrete function declaration, which was pointed out in https://github.com/rust-lang/rust/issues/115199.
This change switches to emitting a proper function declaration instead of a global i8. This allows CFI to work for extern_weak functions. Example:
```
`@_rust_extern_with_linkage_FOO` = internal global ptr `@FOO`
...
declare !type !61 !type !62 !type !63 !type !64 extern_weak void `@FOO(double)` unnamed_addr #6
```
We keep initializing the Rust internal symbol with the function declaration, which preserves the correct behavior for runtime checking the Option.
r? `@rcvalle`
cc `@jakos-sec`
try-job: test-various
Add `From<{integer}>` for `f16`/`f128` impls
This PR adds `impl From<{bool,i8,u8}> for f16` and `impl From<{bool,i8,u8,i16,u16,i32,u32}> for f128`.
The `From<{i64,u64}> for f128` impls are left commented out as adding them would allow using `f128` on stable before it is stabilised like in the following example:
```rust
fn f<T: From<u64>>(x: T) -> T { x }
fn main() {
let x = f(1.0); // the type of the literal is inferred to be `f128`
}
```
None of the impls added in this PR have this issue as they are all, at minimum, also implemented by `f64`.
This PR will need a crater run for the `From<{i32,u32}>` impls, as `f64` is no longer the only float type to implement them (similar to the cause of #125198).
cc `@bjoernager`
r? `@tgross35`
Tracking issue: #116909
added some new test to check for result and options opt
Apologies for the delay. Finally have some time to get back into contributing.
## Context
- Added some tests to show optimization on result and options for 64 and 128 bits
- Relevant issue https://github.com/rust-lang/rust/issues/101210
## Some newb questions from me
- [x] My local llvm IR has `nuw` in `result_nop_match_128` etc whereas [godbolt version](https://rust.godbolt.org/z/Td9zoT5zn) doesn't have. So I put optional there, but not sure if it's desirable (maybe I'm not using the compiled llvm in the repo). I ran the test with
```bash
./x test tests/codegen/try_question_mark_nop.rs
```
- [x] Unless I'm reading it wrongly, but `option_nop_match_128` and `option_nop_traits_128` look to be **not** optimized away?
Update:
Here's the test for future reference
```rust
// CHECK-LABEL: `@option_nop_match_128`
#[no_mangle]
pub fn option_nop_match_128(x: Option<i128>) -> Option<i128> {
// CHECK: start:
// CHECK-NEXT: %trunc = trunc nuw i128 %0 to i1
// CHECK-NEXT: br i1 %trunc, label %bb3, label %bb4
// CHECK: bb3:
// CHECK-NEXT: %2 = getelementptr inbounds {{(nuw )?}}i8, ptr %_0, i64 16
// CHECK-NEXT: store i128 %1, ptr %2, align 16
// CHECK: bb4:
// CHECK-NEXT: %storemerge = phi i128 [ 1, %bb3 ], [ 0, %start ]
// CHECK-NEXT: store i128 %storemerge, ptr %_0, align 16
// CHECK-NEXT: ret void
match x {
Some(x) => Some(x),
None => None,
}
}
```
r? `@scottmcm`
Update sccache to 0.10.0
This time, does it also for Windows and macOS. This unifies the sccache version across all OSes that we use.
r? `@ghost`
try-job: dist-aarch64-apple
try-job: dist-x86_64-apple
try-job: dist-x86_64-msvc
try-job: dist-x86_64-msvc-alt
try-job: dist-i686-msvc
try-job: dist-aarch64-msvc
try-job: dist-x86_64-linux
try-job: dist-x86_64-netbsd
bors
Matthias Krüger
Jieyou Xu
Jakub Beránek
DianQK
bit-aloo
jyn