Dylan DPC [Wed, 12 Oct 2022 16:43:23 +0000 (22:13 +0530)]
Rollup merge of #102623 - davidtwco:translation-eager, r=compiler-errors
translation: eager translation
Part of #100717. See [Zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/336883-i18n/topic/.23100717.20lists!/near/295010720) for additional context.
- **Store diagnostic arguments in a `HashMap`**: Eager translation will enable subdiagnostics to be translated multiple times with different arguments - this requires the ability to replace the value of one argument with a new value, which is better suited to a `HashMap` than the previous storage, a `Vec`.
- **Add `AddToDiagnostic::add_to_diagnostic_with`**: `AddToDiagnostic::add_to_diagnostic_with` is similar to the previous `AddToDiagnostic::add_to_diagnostic` but takes a function that can be used by the caller to modify diagnostic messages originating from the subdiagnostic (such as performing translation eagerly). `add_to_diagnostic` now just calls `add_to_diagnostic_with` with an empty closure.
- **Add `DiagnosticMessage::Eager`**: Add variant of `DiagnosticMessage` for eagerly translated messages
(messages in the target language which don't need translated by the emitter during emission). Also adds `eager_subdiagnostic` function which is intended to be invoked by the diagnostic derive for subdiagnostic fields which are marked as needing eager translation.
- **Support `#[subdiagnostic(eager)]`**: Add support for `eager` argument to the `subdiagnostic` attribute which generates a call to `eager_subdiagnostic`.
- **Finish migrating `rustc_query_system`**: Using eager translation, migrate the remaining repeated cycle stack diagnostic.
- **Split formatting initialization and use in diagnostic derives**: Diagnostic derives have previously had to take special care when ordering the generated code so that fields were not used after a move.
This is unlikely for most fields because a field is either annotated with a subdiagnostic attribute and is thus likely a `Span` and copiable, or is a argument, in which case it is only used once by `set_arg`
anyway.
However, format strings for code in suggestions can result in fields being used after being moved if not ordered carefully. As a result, the derive currently puts `set_arg` calls last (just before emission), such as:
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
diag.emit();
For eager translation, this doesn't work, as the message being translated eagerly can assume that all arguments are available - so arguments _must_ be set first.
Format strings for suggestion code are now separated into two parts - an initialization line that performs the formatting into a variable, and a usage in the subdiagnostic addition.
By separating these parts, the initialization can happen before arguments are set, preserving the desired order so that code compiles, while still enabling arguments to be set before subdiagnostics are added.
let diag = { /* create diagnostic */ };
let __code_0 = format!("{}", __binding_0);
/* + other formatting */
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
- **Remove field ordering logic in diagnostic derive:** Following the approach taken in earlier commits to separate formatting initialization from use in the subdiagnostic derive, simplify the diagnostic derive by removing the field-ordering logic that previously solved this problem.
bors [Wed, 12 Oct 2022 10:51:31 +0000 (10:51 +0000)]
Auto merge of #102460 - flba-eb:fix_85261_prevent_alloc_after_fork, r=thomcc
Prevent UB in child process after calling libc::fork
After calling libc::fork, the child process tried to access a TLS variable when processing a panic. This caused a memory allocation which is UB in the child.
To prevent this from happening, the panic handler will not access the TLS variable in case `panic::always_abort` was called before.
Fixes #85261 (not only on Android systems, but also on Linux/QNX with TLS disabled, see issue for more details)
Main drawbacks of this fix:
* Panic messages can incorrectly omit `core::panic::PanicInfo` struct in case several panics (of multiple threads) occur at the same time. The handler cannot distinguish between multiple panics in different threads or recursive ones in the same thread, but the message will contain a hint about the uncertainty.
* `panic_count::increase()` will be a bit slower as it has an additional `if`, but this should be irrelevant as it is only called in case of a panic.
Dylan DPC [Wed, 12 Oct 2022 05:41:27 +0000 (11:11 +0530)]
Rollup merge of #102924 - notriddle:notriddle/sidebar-link-class, r=GuillaumeGomez
rustdoc: remove unused classes from sidebar links
Since https://github.com/rust-lang/rust/commit/98f05a0282625a5fda6e90ebf3b05a4bd7608f65 removed separate colors from the currently-selected item, there's no need to have item classes on sidebar links.
While cleaning up the CSS to remove unneeded `.content` selectors, this PR changes the `h1.fqn a` CSS selector to just be `h1 a`, so that the header link color selector is less specific than the typed link at the end. Since https://github.com/rust-lang/rust/pull/89506 made docblocks start at `h2`, the main page link header should be the only h1 in the page now.
Dylan DPC [Wed, 12 Oct 2022 05:41:26 +0000 (11:11 +0530)]
Rollup merge of #102890 - camsteffen:adt-sized-representability, r=cjgillot
Check representability in adt_sized_constraint
Now that representability is a query, we can use it to preemptively avoid a cycle in `adt_sized_constraint`.
I moved the representability check into `check_mod_type_wf` to avoid a scenario where rustc quits before checking all the types for representability. This also removes the check from rustdoc, which is alright AFAIK.
Dylan DPC [Wed, 12 Oct 2022 05:41:25 +0000 (11:11 +0530)]
Rollup merge of #102811 - the8472:bufread-memset, r=m-ou-se
Use memset to initialize readbuf
The write loop was found to be slow in #102727
The proper fix is in #102760 but this might still help debug builds and code running under miri by using the write_bytes intrinsic instead of writing one byte at a time.
Dylan DPC [Wed, 12 Oct 2022 05:41:24 +0000 (11:11 +0530)]
Rollup merge of #102187 - b-naber:inline-const-source-info, r=eholk
Use correct location for type tests in promoted constants
Previously we forgot to remap the location in a type test collected when visiting the body of a promoted constant back to the usage location, causing an ICE when trying to get span information for that type test.
Dylan DPC [Wed, 12 Oct 2022 05:41:23 +0000 (11:11 +0530)]
Rollup merge of #102110 - CleanCut:migrate_rustc_passes_diagnostics, r=davidtwco
Migrate rustc_passes diagnostics
Picks up abandoned work from https://github.com/rust-lang/rust/pull/100870
I would like to do this collaboratively, as there is a lot of work! Here's the process:
- Comment below that you are willing to help and I will add you as a collaborator to my `rust` fork (that gives you write access)
- Indicate which file/task you would like to work on (so we don't duplicate work) from the list below
- Do the work, push up a commit, comment that you're done with that file/task
- Repeat until done 😄
### Files to Migrate (in `compiler/rustc_passes/src/`)
- [x] Rebase on current `master` ``@CleanCut``
- [x] Review work from [the earlier PR](https://github.com/rust-lang/rust/pull/100870) and make sure it all looks good
- [x] compiler/rustc_error_messages/locales/en-US/passes.ftl ``@CleanCut``
- [x] compiler/rustc_passes/src/check_attr.rs ``@CleanCut``
- [x] compiler/rustc_passes/src/errors.rs ``@CleanCut``
- [x] compiler/rustc_passes/src/lang_items.rs ``@CleanCut``
- [x] compiler/rustc_passes/src/lib.rs ``@CleanCut``
- [x] compiler/rustc_passes/src/weak_lang_items.rs ``@CleanCut``
- Add more doc comments for three modules (rust-lang/cargo#11207)
- docs: fix (rust-lang/cargo#11208)
- Add completions for `cargo remove` (rust-lang/cargo#11204)
- Config file loaded via CLI takes priority over env vars (rust-lang/cargo#11077)
- Use `#[default]` when possible (rust-lang/cargo#11197)
- Implement RFC 3289: source replacement ambiguity (rust-lang/cargo#10907)
- Use correct version of cargo in test (rust-lang/cargo#11193)
- Check empty input for login (rust-lang/cargo#11145)
- Add retry support to sparse registries (rust-lang/cargo#11069)
- Add more doc comments for three modules (rust-lang/cargo#11207)
- docs: fix (rust-lang/cargo#11208)
- Add completions for `cargo remove` (rust-lang/cargo#11204)
- Config file loaded via CLI takes priority over env vars (rust-lang/cargo#11077)
- Use `#[default]` when possible (rust-lang/cargo#11197)
- Implement RFC 3289: source replacement ambiguity (rust-lang/cargo#10907)
- Use correct version of cargo in test (rust-lang/cargo#11193)
- Check empty input for login (rust-lang/cargo#11145)
- Add retry support to sparse registries (rust-lang/cargo#11069)
Matthias Krüger [Tue, 11 Oct 2022 16:59:49 +0000 (18:59 +0200)]
Rollup merge of #102685 - nbdd0121:unwind, r=m-ou-se
Interpret EH actions properly
The EH actions stored in the LSDA follows the format of GCC except table (even for LLVM-generated code). An missing action in the table is the encoding for `Terminate`, see https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/eh_personality.cc#L522-L526.
The currently code interprets it as `None`, as a workaround for #35011, an issue that seems to occur in LLVM 3.7 and not after 3.9. These are very old versions of LLVM and we don't support them anymore, so remove this workaround and interpret them properly.
Note that LLVM currently does not emit any `Terminate` actions, but GCC does. Although GCC backend currently doesn't do unwinding, removing it preemptively would prevent future developers from wasting time to figure out what's wrong.
Matthias Krüger [Tue, 11 Oct 2022 16:59:48 +0000 (18:59 +0200)]
Rollup merge of #102612 - JhonnyBillM:migrate-codegen-ssa-to-diagnostics-structs, r=davidtwco
Migrate `codegen_ssa` to diagnostics structs - [Part 1]
Initial migration of `codegen_ssa`. Going to split this crate migration in at least two PRs in order to avoid a huge PR and to quick off some questions around:
1. Translating messages from "external" crates.
2. Interfacing with OS messages.
3. Adding UI tests while migrating diagnostics.
Matthias Krüger [Tue, 11 Oct 2022 16:59:46 +0000 (18:59 +0200)]
Rollup merge of #101774 - Riolku:atomic-update-aba, r=m-ou-se
Warn about safety of `fetch_update`
Specifically as it relates to the ABA problem.
`fetch_update` is a useful function, and one that isn't provided by, say, C++. However, this does not mean the function is magic. It is implemented in terms of `compare_exchange_weak`, and in particular, suffers from the ABA problem. See the following code, which is a naive implementation of `pop` in a lock-free queue:
This code is unsound if called from multiple threads because of the ABA problem. Specifically, suppose nodes are allocated with `Box`. Suppose the following sequence happens:
```
Initial: Queue is X -> Y.
Thread A: Starts popping, is pre-empted.
Thread B: Pops successfully, twice, leaving the queue empty.
Thread C: Pushes, and `Box` returns X (very common for allocators)
Thread A: Wakes up, sees the head is still X, and stores Y as the new head.
```
But `Y` is deallocated. This is undefined behaviour.
Adding a note about this problem to `fetch_update` should hopefully prevent users from being misled, and also, a link to this common problem is, in my opinion, an improvement to our docs on atomics.
Matthias Krüger [Tue, 11 Oct 2022 16:59:45 +0000 (18:59 +0200)]
Rollup merge of #100387 - cjgillot:hygiene-trait-impl, r=petrochenkov
Check uniqueness of impl items by trait item when applicable.
When checking uniqueness of item names in impl blocks, we currently use the same definition of hygiene as for toplevel items. This means that a plain item and one generated by a macro 2.0 do not collide.
This hygiene rule does not match with how impl items resolve to associated trait items. As a consequence, we misdiagnose the trait impls.
This PR proposes to consider that trait impl items are uses of the corresponding trait items during resolution, instead of checking for duplicates later. An error is emitted when a trait impl item is used twice.
There should be no stable breakage, since macros 2.0 are still unstable.
This commit does have to change `h1.fqn a` to just be `h1 a`, so that the
header link color selector is less specific than the typed link at the end.
Since #89506 made docblocks start at `h2`, the main page link header should
be the only h1 in the page now.
Yuki Okushi [Tue, 11 Oct 2022 09:37:55 +0000 (18:37 +0900)]
Rollup merge of #102859 - cjgillot:collect-lifetimes, r=oli-obk
Move lifetime resolution module to rustc_hir_analysis.
Now that lifetime resolution has been removed from it, this file has nothing to do in `rustc_resolve`. It's purpose is to compute Debruijn indices for lifetimes, so let's put it in type collection.
Yuki Okushi [Tue, 11 Oct 2022 09:37:54 +0000 (18:37 +0900)]
Rollup merge of #102589 - RalfJung:scoped-threads-dangling, r=m-ou-se
scoped threads: pass closure through MaybeUninit to avoid invalid dangling references
The `main` function defined here looks roughly like this, if it were written as a more explicit stand-alone function:
```rust
// Not showing all the `'lifetime` tracking, the point is that
// this closure might live shorter than `thread`.
fn thread(control: ..., closure: impl FnOnce() + 'lifetime) {
closure();
control.signal_done();
// A lot of time can pass here.
}
```
Note that `thread` continues to run even after `signal_done`! Now consider what happens if the `closure` captures a reference of lifetime `'lifetime`:
- The type of `closure` is a struct (the implicit unnameable closure type) with a `&'lifetime mut T` field. References passed to a function are marked with `dereferenceable`, which is LLVM speak for *this reference will remain live for the entire duration of this function*.
- The closure runs, `signal_done` runs. Then -- potentially -- this thread gets scheduled away and the main thread runs, seeing the signal and returning to the user. Now `'lifetime` ends and the memory the reference points to might be deallocated.
- Now we have UB! The reference that as passed to `thread` with the promise of remaining live for the entire duration of the function, actually got deallocated while the function still runs. Oops.
Long-term I think we should be able to use `ManuallyDrop` to fix this without `unsafe`, or maybe a new `MaybeDangling` type. I am working on an RFC for that. But in the mean time it'd be nice to fix this so that Miri with `-Zmiri-retag-fields` (which is needed for "full enforcement" of all the LLVM flags we generate) stops erroring on scoped threads.
bors [Tue, 11 Oct 2022 08:09:41 +0000 (08:09 +0000)]
Auto merge of #102755 - pcc:data-local-tmp, r=Mark-Simulacrum
tools/remote-test-{server,client}: Use /data/local/tmp on Android
The /data/tmp directory does not exist, at least not on recent versions of Android, which currently leads to test failures on that platform. I checked a virtual device running AOSP master and a Nexus 5 running Android Marshmallow and on both devices the /data/tmp directory does not exist and /data/local/tmp does, so let's switch to /data/local/tmp.
bors [Tue, 11 Oct 2022 04:27:13 +0000 (04:27 +0000)]
Auto merge of #102724 - pcc:scs-fix-test, r=Mark-Simulacrum
Fix the sanitizer_scs_attr_check.rs test
The test is failing when targeting aarch64 Android. The intent appears to have been to look for a function attributes comment (or the absence of one) on the line preceding the function declaration. But this isn't quite possible with FileCheck and the test as written was looking for a line with `no_scs` after a line with `scs`, which doesn't appear in the output. Instead, match on the function attributes comment on the line following the demangled function name comment.
Matthias Krüger [Mon, 10 Oct 2022 18:47:34 +0000 (20:47 +0200)]
Rollup merge of #102876 - SparrowLii:import-candidate, r=fee1-dead
suggest candidates for unresolved import
Currently we prompt suggestion of candidates(help notes of `use xxx::yyy`) for names which cannot be resolved, but we don't do that for import statements themselves that couldn't be resolved. It seems reasonable to add candidate help information for these statements as well.
Fixes #102711
Matthias Krüger [Mon, 10 Oct 2022 18:47:33 +0000 (20:47 +0200)]
Rollup merge of #102871 - notriddle:notriddle/trait-impl-anchor, r=GuillaumeGomez
rustdoc: clean up overly complex `.trait-impl` CSS selectors
When added in 45964368f4a2e31c94e9bcf1cef933c087d21544, these multi-class selectors were present in the initial commit, but no reason was given why the shorter selector wouldn't work.
To check-in `rustc-src` for hermetic builds in environments with
restrictive `.gitignore` policies, one has to remove these
`tests/.gitignore` and patch the respective
`.cargo-checksum.json`.`syn` >1.0.101 includes dtolnay/syn@3c49303bed7a,
which removes its `tests/.gitignore`. Now the `syn` crates.io package
has no `.gitignore`.
[`rustc-src`'s `vendor`][] is produced from the root `Cargo.toml`,
`src/tools/rust-analyzer/Cargo.toml`,
`compiler/rustc_codegen_cranelift/Cargo.toml`, and
`src/bootstrap/Cargo.toml`. `rustc_codegen_cranelift` does not use
`syn`.
David Wood [Mon, 3 Oct 2022 15:10:34 +0000 (16:10 +0100)]
macros: simplify field ordering in diag derive
Following the approach taken in earlier commits to separate formatting
initialization from use in the subdiagnostic derive, simplify the
diagnostic derive by removing the field-ordering logic that previously
solved this problem.
David Wood [Mon, 3 Oct 2022 13:28:02 +0000 (14:28 +0100)]
macros: separate suggestion fmt'ing and emission
Diagnostic derives have previously had to take special care when
ordering the generated code so that fields were not used after a move.
This is unlikely for most fields because a field is either annotated
with a subdiagnostic attribute and is thus likely a `Span` and copiable,
or is a argument, in which case it is only used once by `set_arg`
anyway.
However, format strings for code in suggestions can result in fields
being used after being moved if not ordered carefully. As a result, the
derive currently puts `set_arg` calls last (just before emission), such
as:
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
diag.emit();
```
For eager translation, this doesn't work, as the message being
translated eagerly can assume that all arguments are available - so
arguments _must_ be set first.
Format strings for suggestion code are now separated into two parts - an
initialization line that performs the formatting into a variable, and a
usage in the subdiagnostic addition.
By separating these parts, the initialization can happen before
arguments are set, preserving the desired order so that code compiles,
while still enabling arguments to be set before subdiagnostics are
added.
```rust
let diag = { /* create diagnostic */ };
let __code_0 = format!("{}", __binding_0);
/* + other formatting */
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
David Wood [Mon, 3 Oct 2022 13:14:51 +0000 (14:14 +0100)]
errors: `DiagnosticMessage::Eager`
Add variant of `DiagnosticMessage` for eagerly translated messages
(messages in the target language which don't need translated by the
emitter during emission). Also adds `eager_subdiagnostic` function which
is intended to be invoked by the diagnostic derive for subdiagnostic
fields which are marked as needing eager translation.
David Wood [Mon, 3 Oct 2022 13:09:05 +0000 (14:09 +0100)]
errors: `AddToDiagnostic::add_to_diagnostic_with`
`AddToDiagnostic::add_to_diagnostic_with` is similar to the previous
`AddToDiagnostic::add_to_diagnostic` but takes a function that can be
used by the caller to modify diagnostic messages originating from the
subdiagnostic (such as performing translation eagerly).
`add_to_diagnostic` now just calls `add_to_diagnostic_with` with an
empty closure.
David Wood [Mon, 3 Oct 2022 13:02:49 +0000 (14:02 +0100)]
errors: use `HashMap` to store diagnostic args
Eager translation will enable subdiagnostics to be translated multiple
times with different arguments - this requires the ability to replace
the value of one argument with a new value, which is better suited to a
`HashMap` than the previous storage, a `Vec`.
bors [Mon, 10 Oct 2022 12:09:21 +0000 (12:09 +0000)]
Auto merge of #96711 - emilio:inline-slice-clone, r=nikic
slice: #[inline] a couple iterator methods.
The one I care about and actually saw in the wild not getting inlined is
clone(). We ended up doing a whole function call for something that just
copies two pointers.
I ended up marking as_slice / as_ref as well because make_slice is
inline(always) itself, and is also the kind of think that can kill
performance in hot loops if you expect it to get inlined. But happy to
undo those.
bors [Mon, 10 Oct 2022 09:12:06 +0000 (09:12 +0000)]
Auto merge of #102875 - Dylan-DPC:rollup-zwcq8h9, r=Dylan-DPC
Rollup of 6 pull requests
Successful merges:
- #99696 (Uplift `clippy::for_loops_over_fallibles` lint into rustc)
- #102055 (Move some tests to more reasonable directories)
- #102786 (Remove tuple candidate, nothing special about it)
- #102794 (Make tests capture the error printed by a Result return)
- #102853 (Skip chained OpaqueCast when building captures.)
- #102868 (Rename `AssocItemKind::TyAlias` to `AssocItemKind::Type`)
Dylan DPC [Mon, 10 Oct 2022 08:13:41 +0000 (13:43 +0530)]
Rollup merge of #102794 - dtolnay:termination, r=thomcc
Make tests capture the error printed by a Result return
An error returned by tests previously would get written directly to stderr, instead of to the capture buffer set up by the test harness. This PR makes it write to the capture buffer so that it can be integrated as part of the test output by build tools such as `buck test`, since being able to read the error message returned by a test is pretty critical to debugging why the test failed.
Dylan DPC [Mon, 10 Oct 2022 08:13:40 +0000 (13:43 +0530)]
Rollup merge of #99696 - WaffleLapkin:uplift, r=fee1-dead
Uplift `clippy::for_loops_over_fallibles` lint into rustc
This PR, as the title suggests, uplifts [`clippy::for_loops_over_fallibles`] lint into rustc. This lint warns for code like this:
```rust
for _ in Some(1) {}
for _ in Ok::<_, ()>(1) {}
```
i.e. directly iterating over `Option` and `Result` using `for` loop.
There are a number of suggestions that this PR adds (on top of what clippy suggested):
1. If the argument (? is there a better name for that expression) of a `for` loop is a `.next()` call, then we can suggest removing it (or rather replacing with `.by_ref()` to allow iterator being used later)
```rust
for _ in iter.next() {}
// turns into
for _ in iter.by_ref() {}
```
2. (otherwise) We can suggest using `while let`, this is useful for non-iterator, iterator-like things like [async] channels
```rust
for _ in rx.recv() {}
// turns into
while let Some(_) = rx.recv() {}
```
3. If the argument type is `Result<impl IntoIterator, _>` and the body has a `Result<_, _>` type, we can suggest using `?`
```rust
for _ in f() {}
// turns into
for _ in f()? {}
```
4. To preserve the original behavior and clear intent, we can suggest using `if let`
```rust
for _ in f() {}
// turns into
if let Some(_) = f() {}
```
(P.S. `Some` and `Ok` are interchangeable depending on the type)
I still feel that the lint wording/look is somewhat off, so I'll be happy to hear suggestions (on how to improve suggestions :D)!
Michael Howell [Mon, 10 Oct 2022 06:19:50 +0000 (23:19 -0700)]
rustdoc: clean up overly complex `.trait-impl` CSS selectors
When added in 45964368f4a2e31c94e9bcf1cef933c087d21544, these multi-class
selectors were present in the initial commit, but no reason was given why
the shorter selector wouldn't work.
bors [Mon, 10 Oct 2022 06:18:58 +0000 (06:18 +0000)]
Auto merge of #94381 - Kobzol:llvm-bolt, r=Mark-Simulacrum
Use BOLT in CI to optimize LLVM
This PR adds an optimization step in the Linux `dist` CI pipeline that uses [BOLT](https://github.com/llvm/llvm-project/tree/main/bolt) to optimize the `libLLVM.so` library built by boostrap.
Steps:
- [x] Use LLVM 15 as a bootstrap compiler and use it to build BOLT
- [x] Compile LLVM with support for relocations (`-DCMAKE_SHARED_LINKER_FLAGS="-Wl,-q"`)
- [x] Gather profile data using instrumented LLVM
- [x] Apply profile to LLVM that has already been PGOfied
- [x] Run with BOLT profiling on more benchmarks
- [x] Decide on the order of optimization (PGO -> BOLT?)
- [x] Decide how we should get `bolt` (currently we use the host `bolt`)
- [x] Clean up
The latest perf results can be found [here](https://github.com/rust-lang/rust/pull/94381#issuecomment-1258269440). The current CI build time with BOLT applied is around 1h 55 minutes.
Yuki Okushi [Mon, 10 Oct 2022 01:23:03 +0000 (10:23 +0900)]
Rollup merge of #102275 - Urgau:stabilize-half_open_range_patterns, r=cjgillot
Stabilize `half_open_range_patterns`
This PR stabilize `feature(half_open_range_patterns)`:
```
Allows using `..=X` as a pattern.
```
And adds a new `feature(half_open_range_patterns_in_slices)` for the slice part, https://github.com/rust-lang/rust/pull/102275#issuecomment-1267422806.
The FCP was completed in https://github.com/rust-lang/rust/issues/67264.
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