Loosen the bound on the Debug implementation of Weak. #90291

geeklint · 2021-10-26T01:51:05Z

Both rc::Weak<T> and sync::Weak<T> currently require T: Debug in their own Debug implementations, but they don't currently use it; they only ever print a fixed string.

A general implementation of Debug for Weak that actually attempts to upgrade and rely on the contents is unlikely in the future because it may have unbounded recursion in the presence of reference cycles, which Weak is commonly used in. (This was the justification for why the current implementation was implemented the way it is).

When I brought it up on the forum, it was suggested that, even if an implementation is specialized in the future that relies on the data stored within the Weak, it would likely rely on specialization anyway, and could therefore easily specialize on the Debug bound as well.

rust-highfive · 2021-10-26T01:51:08Z

r? @kennytm

(rust-highfive has picked a reviewer for you, use r? to override)

scottmcm · 2021-10-26T07:19:28Z

library/alloc/src/rc.rs

@@ -2393,7 +2393,7 @@ impl<T: ?Sized> Clone for Weak<T> {
 }

 #[stable(feature = "rc_weak", since = "1.4.0")]
-impl<T: ?Sized + fmt::Debug> fmt::Debug for Weak<T> {
+impl<T: ?Sized> fmt::Debug for Weak<T> {


(Wait to hear what libs-api says before bothering doing this but) consider putting a doc comment on the impl to say that the Debug impl will not include the data from the item to make it clear to users that that's what they're going to get. And also to ensure there's no future PR to "hey, can we add Debug to show what's in a Weak" 🙂

And also to ensure there's no future PR to "hey, can we add Debug to show what's in a Weak" 🙂

as explained this the PR description, this can still be done via specialization if desired.

joshtriplett · 2021-10-30T22:04:40Z

This seems reasonable to me for exactly the stated reason: the Debug impl for Weak should never try to upgrade to get access to the thing it contains in order to print it.

@rfcbot merge

rfcbot · 2021-10-30T22:04:41Z

Team member @joshtriplett has proposed to merge this. The next step is review by the rest of the tagged team members:

Concerns:

~~better-use-case~~ resolved by Loosen the bound on the Debug implementation of Weak. #90291 (comment)

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

BurntSushi · 2021-10-31T12:42:18Z

The reasoning here all makes sense to me. But what I'm missing or not understanding is a reason to do this in the first place. What concrete benefit do we gain by relaxing this impl?

geeklint · 2021-10-31T13:30:16Z

I specifically ran into this while attempting to add a #[derive(Debug)] to a custom type that contained a Weak. I had the existing understanding that Weak always formatted as just "(Weak)" so I was mildly surprised when the derive didn't work.

I questioned why the bound was there in the first place and most people I spoke to seemed to share the understanding that it was a remnant of the original implementation that was no longer required, and that therefore this PR would be worthwhile.

BurntSushi · 2021-10-31T14:34:42Z

@geeklint interesting. Would it be possible to show a short code example? I think the derive would only not work if the type wrapped by your Weak didn't impl Debug either? That seems a little odd to me, but I could be misunderstanding. I think code will help make things more concrete for me.

I questioned why the bound was there in the first place and most people I spoke to seemed to share the understanding that it was a remnant of the original implementation that was no longer required, and that therefore this PR would be worthwhile.

Yeah that makes sense. I just want to make sure we have all our bases covered here, since this isn't a change we can walk back. (Folks have mentioned specialization, but specialization is in a pretty weird state.) If this extra restriction isn't actually getting in the way of anything, then I'm skeptical of removing it.

geeklint · 2021-10-31T21:27:17Z

@BurntSushi Yes you're correct, the type I was wrapping did not implement Debug - it probably could have but I chose not to. This is a rough paraphrase of the code I had:

struct Shared {
    ptr: AtomicPtr<_>,
    index: AtomicUsize,
}

// the recv side has the owned copy, and would have a custom Debug implementation
pub struct RecvSide {
    shared: Arc<Shared>,
}

// the send side I was hoping could be simplified by using #[derive]
#[derive(Debug)]
pub struct SendSide {
    shared: Weak<Shared>,
}

I intentionally didn't want to #[derive(Debug)] on the Shared item because the contents are implementation detail in my library, and I'm not personally a fan of the Debug implementations for Atomics (that opinion is not related to this PR). I suppose I could have manually implemented Debug for Shared so that it could have been derived for the public-facing types - I guess didn't think of that at the time - but I still think if there's no conceivable plan to rely on the T: Debug in Weak<T>, it doesn't need to retain the bound.

BurntSushi · 2021-11-01T12:34:37Z

Thanks for sharing! It makes me a little uneasy to do this without something more compelling to be honest. If you're already doing a custom debug impl for Arc<Shared>, it doesn't seem that bad to do one more for Weak<Shared>. I grant that everyone here is right in that Weak probably doesn't need the fmt::Debug restriction, but I'd rather take the conservative side of things here: if the restriction isn't costing us much and putting it back would be difficult should we turn out to be wrong, then I'd rather just keep it.

@rfcbot concern better-use-case

yaahc · 2021-12-10T20:51:12Z

Hey @geeklint, are you still interested in pursuing this change?

geeklint · 2021-12-11T17:01:39Z

If the consensus doesn't find the use case compelling enough, I'm content to close this issue.

If I may conclude with a more theoretical postulation, I would suggest the idea that the Weak impl is overly restrictive is dependent on the existence of a type which intentionally doesn't impl Debug. If the widely held understanding is that all types should have a Debug implementation, then I support that the case I ran into (where T does not impl Debug) is almost certainly a "bug" with T, rather than with the bound on Weak.

If someone can provide an example of a type which shouldn't implement Debug, then I think this change is worth reconsidering, but as I do not personally have such an example, I no longer have a convincing argument for this change.

joshtriplett · 2021-12-22T21:48:52Z

I personally do think this is a sufficient use case already: derive(Debug) should work on types containing Weak. I don't think it's a given that you always need to manually implement Debug yourself for Arc<T> to want to derive Debug for a type containing a Weak<T>. In particular, it makes sense to hand out "handle"-ish data structures containing a Weak<T>.

m-ou-se · 2022-01-19T20:56:21Z

Some related context: The Debug implementation of Mutex tries to lock the mutex and either prints just 'locked' if it was locked, or it Debug prints the T within the Mutex<T> if it wasn't locked.

yaahc · 2022-02-11T19:12:23Z

Nominating this for discussion in next weeks libs-api team meeting since it seems to be blocked currently.

m-ou-se · 2022-02-16T20:10:19Z

@BurntSushi any updates on your position after the comments since your last comment?

BurntSushi · 2022-02-23T18:32:25Z

I think I would personally still like to see a more compelling example. @joshtriplett would it be possible to show something where you aren't doing a debug impl by hand on Arc and want a derive on Weak?

To me, I don't have any argument against doing this other than the standard conservative take: we can't undo this once done, so we should be sure we're on firm ground before doing so. I don't feel super strongly here, so I'm not necessarily looking for something super compelling.

geeklint · 2022-03-16T14:34:33Z

I thought of a potentially valuable example where the T in Arc/Rc/Weak would not implement Debug: trait objects. While there's a manual impl of Debug for dyn Any, other traits don't get the same. For instance, Weak<dyn Fn()> doesn't implement Debug (and user code can't implement Debug for it manually).

carbotaniuman · 2022-07-15T02:38:17Z

I've come across a use-case here for an interpreter, where the only reason I can't derive Debug is because Weak isn't Debug. The object basically stores an Arc to one object, and a Weak to two others in a sort of linked-list for reference.

thomcc · 2022-08-25T23:33:28Z

This seems to have gotten the needed checkboxes, but the FCP never began. Does anybody know the invocation to trigger that?

BurntSushi · 2022-12-28T13:21:12Z

@thomcc It's because I have a concern registered, which blocks FCP. I hadn't seen the latest replies here (or forgot about them), but I think it's good enough for me.

@rfcbot resolve better-use-case

rfcbot · 2022-12-28T13:21:17Z

🔔 This is now entering its final comment period, as per the review above. 🔔

rfcbot · 2023-01-07T13:23:44Z

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

This will be merged soon.

dtolnay · 2023-01-07T16:15:34Z

@bors r+

bors · 2023-01-07T16:15:36Z

📌 Commit ca7297b has been approved by dtolnay

It is now in the queue for this repository.

bors · 2023-01-08T22:40:42Z

⌛ Testing commit ca7297b with merge a377893...

bors · 2023-01-09T01:09:07Z

☀️ Test successful - checks-actions
Approved by: dtolnay
Pushing a377893 to master...

rust-timer · 2023-01-09T03:30:38Z

Finished benchmarking commit (a377893): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.7%	[-1.1%, -0.5%]	8
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	1.7%	[1.7%, 1.7%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Cycles

This benchmark run did not return any relevant results for this metric.

Pkgsrc changes: * Adjust patches and cargo checksums to new versions. Upstream changes: Version 1.68.0 (2023-03-09) =========================== Language -------- - [Stabilize default_alloc_error_handler] (rust-lang/rust#102318) This allows usage of `alloc` on stable without requiring the definition of a handler for allocation failure. Defining custom handlers is still unstable. - [Stabilize `efiapi` calling convention.] (rust-lang/rust#105795) - [Remove implicit promotion for types with drop glue] (rust-lang/rust#105085) Compiler -------- - [Change `bindings_with_variant_name` to deny-by-default] (rust-lang/rust#104154) - [Allow .. to be parsed as let initializer] (rust-lang/rust#105701) - [Add `armv7-sony-vita-newlibeabihf` as a tier 3 target] (rust-lang/rust#105712) - [Always check alignment during compile-time const evaluation] (rust-lang/rust#104616) - [Disable "split dwarf inlining" by default.] (rust-lang/rust#106709) - [Add vendor to Fuchsia's target triple] (rust-lang/rust#106429) - [Enable sanitizers for s390x-linux] (rust-lang/rust#107127) Libraries --------- - [Loosen the bound on the Debug implementation of Weak.] (rust-lang/rust#90291) - [Make `std::task::Context` !Send and !Sync] (rust-lang/rust#95985) - [PhantomData layout guarantees] (rust-lang/rust#104081) - [Don't derive Debug for `OnceWith` & `RepeatWith`] (rust-lang/rust#104163) - [Implement DerefMut for PathBuf] (rust-lang/rust#105018) - [Add O(1) `Vec -> VecDeque` conversion guarantee] (rust-lang/rust#105128) - [Leak amplification for peek_mut() to ensure BinaryHeap's invariant is always met] (rust-lang/rust#105851) Stabilized APIs --------------- - [`{core,std}::pin::pin!`] (https://doc.rust-lang.org/stable/std/pin/macro.pin.html) - [`impl From<bool> for {f32,f64}`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#impl-From%3Cbool%3E-for-f32) - [`std::path::MAIN_SEPARATOR_STR`] (https://doc.rust-lang.org/stable/std/path/constant.MAIN_SEPARATOR_STR.html) - [`impl DerefMut for PathBuf`] (https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#impl-DerefMut-for-PathBuf) These APIs are now stable in const contexts: - [`VecDeque::new`] (https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.new) Cargo ----- - [Stabilize sparse registry support for crates.io] (rust-lang/cargo#11224) - [`cargo build --verbose` tells you more about why it recompiles.] (rust-lang/cargo#11407) - [Show progress of crates.io index update even `net.git-fetch-with-cli` option enabled] (rust-lang/cargo#11579) Misc ---- Compatibility Notes ------------------- - [Add `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` to future-incompat report] (rust-lang/rust#103418) - [Only specify `--target` by default for `-Zgcc-ld=lld` on wasm] (rust-lang/rust#101792) - [Bump `IMPLIED_BOUNDS_ENTAILMENT` to Deny + ReportNow] (rust-lang/rust#106465) - [`std::task::Context` no longer implements Send and Sync] (rust-lang/rust#95985) nternal Changes ---------------- These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Encode spans relative to the enclosing item] (rust-lang/rust#84762) - [Don't normalize in AstConv] (rust-lang/rust#101947) - [Find the right lower bound region in the scenario of partial order relations] (rust-lang/rust#104765) - [Fix impl block in const expr] (rust-lang/rust#104889) - [Check ADT fields for copy implementations considering regions] (rust-lang/rust#105102) - [rustdoc: simplify JS search routine by not messing with lev distance] (rust-lang/rust#105796) - [Enable ThinLTO for rustc on `x86_64-pc-windows-msvc`] (rust-lang/rust#103591) - [Enable ThinLTO for rustc on `x86_64-apple-darwin`] (rust-lang/rust#103647)

Pkgsrc changes: * Adjust patches (add & remove) and cargo checksums to new versions. * It's conceivable that the workaround for LLVM based NetBSD works even less in this version (ref. PKGSRC_HAVE_LIBCPP not having a corresponding patch anymore). Upstream changes: Version 1.68.2 (2023-03-28) =========================== - [Update the GitHub RSA host key bundled within Cargo] (rust-lang/cargo#11883). The key was [rotated by GitHub] (https://github.blog/2023-03-23-we-updated-our-rsa-ssh-host-key/) on 2023-03-24 after the old one leaked. - [Mark the old GitHub RSA host key as revoked] (rust-lang/cargo#11889). This will prevent Cargo from accepting the leaked key even when trusted by the system. - [Add support for `@revoked` and a better error message for `@cert-authority` in Cargo's SSH host key verification] (rust-lang/cargo#11635) Version 1.68.1 (2023-03-23) =========================== - [Fix miscompilation in produced Windows MSVC artifacts] (rust-lang/rust#109094) This was introduced by enabling ThinLTO for the distributed rustc which led to miscompilations in the resulting binary. Currently this is believed to be limited to the -Zdylib-lto flag used for rustc compilation, rather than a general bug in ThinLTO, so only rustc artifacts should be affected. - [Fix --enable-local-rust builds] (rust-lang/rust#109111) - [Treat `$prefix-clang` as `clang` in linker detection code] (rust-lang/rust#109156) - [Fix panic in compiler code] (rust-lang/rust#108162) Version 1.68.0 (2023-03-09) =========================== Language -------- - [Stabilize default_alloc_error_handler] (rust-lang/rust#102318) This allows usage of `alloc` on stable without requiring the definition of a handler for allocation failure. Defining custom handlers is still unstable. - [Stabilize `efiapi` calling convention.] (rust-lang/rust#105795) - [Remove implicit promotion for types with drop glue] (rust-lang/rust#105085) Compiler -------- - [Change `bindings_with_variant_name` to deny-by-default] (rust-lang/rust#104154) - [Allow .. to be parsed as let initializer] (rust-lang/rust#105701) - [Add `armv7-sony-vita-newlibeabihf` as a tier 3 target] (rust-lang/rust#105712) - [Always check alignment during compile-time const evaluation] (rust-lang/rust#104616) - [Disable "split dwarf inlining" by default.] (rust-lang/rust#106709) - [Add vendor to Fuchsia's target triple] (rust-lang/rust#106429) - [Enable sanitizers for s390x-linux] (rust-lang/rust#107127) Libraries --------- - [Loosen the bound on the Debug implementation of Weak.] (rust-lang/rust#90291) - [Make `std::task::Context` !Send and !Sync] (rust-lang/rust#95985) - [PhantomData layout guarantees] (rust-lang/rust#104081) - [Don't derive Debug for `OnceWith` & `RepeatWith`] (rust-lang/rust#104163) - [Implement DerefMut for PathBuf] (rust-lang/rust#105018) - [Add O(1) `Vec -> VecDeque` conversion guarantee] (rust-lang/rust#105128) - [Leak amplification for peek_mut() to ensure BinaryHeap's invariant is always met] (rust-lang/rust#105851) Stabilized APIs --------------- - [`{core,std}::pin::pin!`] (https://doc.rust-lang.org/stable/std/pin/macro.pin.html) - [`impl From<bool> for {f32,f64}`] (https://doc.rust-lang.org/stable/std/primitive.f32.html#impl-From%3Cbool%3E-for-f32) - [`std::path::MAIN_SEPARATOR_STR`] (https://doc.rust-lang.org/stable/std/path/constant.MAIN_SEPARATOR_STR.html) - [`impl DerefMut for PathBuf`] (https://doc.rust-lang.org/stable/std/path/struct.PathBuf.html#impl-DerefMut-for-PathBuf) These APIs are now stable in const contexts: - [`VecDeque::new`] (https://doc.rust-lang.org/stable/std/collections/struct.VecDeque.html#method.new) Cargo ----- - [Stabilize sparse registry support for crates.io] (rust-lang/cargo#11224) - [`cargo build --verbose` tells you more about why it recompiles.] (rust-lang/cargo#11407) - [Show progress of crates.io index update even `net.git-fetch-with-cli` option enabled] (rust-lang/cargo#11579) Misc ---- Compatibility Notes ------------------- - [Add `SEMICOLON_IN_EXPRESSIONS_FROM_MACROS` to future-incompat report] (rust-lang/rust#103418) - [Only specify `--target` by default for `-Zgcc-ld=lld` on wasm] (rust-lang/rust#101792) - [Bump `IMPLIED_BOUNDS_ENTAILMENT` to Deny + ReportNow] (rust-lang/rust#106465) - [`std::task::Context` no longer implements Send and Sync] (rust-lang/rust#95985) nternal Changes ---------------- These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Encode spans relative to the enclosing item] (rust-lang/rust#84762) - [Don't normalize in AstConv] (rust-lang/rust#101947) - [Find the right lower bound region in the scenario of partial order relations] (rust-lang/rust#104765) - [Fix impl block in const expr] (rust-lang/rust#104889) - [Check ADT fields for copy implementations considering regions] (rust-lang/rust#105102) - [rustdoc: simplify JS search routine by not messing with lev distance] (rust-lang/rust#105796) - [Enable ThinLTO for rustc on `x86_64-pc-windows-msvc`] (rust-lang/rust#103591) - [Enable ThinLTO for rustc on `x86_64-apple-darwin`] (rust-lang/rust#103647) Version 1.67.0 (2023-01-26) ========================== Language -------- - [Make `Sized` predicates coinductive, allowing cycles.] (rust-lang/rust#100386) - [`#[must_use]` annotations on `async fn` also affect the `Future::Output`.] (rust-lang/rust#100633) - [Elaborate supertrait obligations when deducing closure signatures.] (rust-lang/rust#101834) - [Invalid literals are no longer an error under `cfg(FALSE)`.] (rust-lang/rust#102944) - [Unreserve braced enum variants in value namespace.] (rust-lang/rust#103578) Compiler -------- - [Enable varargs support for calling conventions other than `C` or `cdecl`.] (rust-lang/rust#97971) - [Add new MIR constant propagation based on dataflow analysis.] (rust-lang/rust#101168) - [Optimize field ordering by grouping m\*2^n-sized fields with equivalently aligned ones.] (rust-lang/rust#102750) - [Stabilize native library modifier `verbatim`.] (rust-lang/rust#104360) Added and removed targets: - [Add a tier 3 target for PowerPC on AIX] (rust-lang/rust#102293), `powerpc64-ibm-aix`. - [Add a tier 3 target for the Sony PlayStation 1] (rust-lang/rust#102689), `mipsel-sony-psx`. - [Add tier 3 `no_std` targets for the QNX Neutrino RTOS] (rust-lang/rust#102701), `aarch64-unknown-nto-qnx710` and `x86_64-pc-nto-qnx710`. - [Remove tier 3 `linuxkernel` targets] (rust-lang/rust#104015) (not used by the actual kernel). Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - [Merge `crossbeam-channel` into `std::sync::mpsc`.] (rust-lang/rust#93563) - [Fix inconsistent rounding of 0.5 when formatted to 0 decimal places.] (rust-lang/rust#102935) - [Derive `Eq` and `Hash` for `ControlFlow`.] (rust-lang/rust#103084) - [Don't build `compiler_builtins` with `-C panic=abort`.] (rust-lang/rust#103786) Stabilized APIs --------------- - [`{integer}::checked_ilog`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog) - [`{integer}::checked_ilog2`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog2) - [`{integer}::checked_ilog10`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.checked_ilog10) - [`{integer}::ilog`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog) - [`{integer}::ilog2`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog2) - [`{integer}::ilog10`] (https://doc.rust-lang.org/stable/std/primitive.i32.html#method.ilog10) - [`NonZeroU*::ilog2`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog2) - [`NonZeroU*::ilog10`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#method.ilog10) - [`NonZero*::BITS`] (https://doc.rust-lang.org/stable/std/num/struct.NonZeroU32.html#associatedconstant.BITS) These APIs are now stable in const contexts: - [`char::from_u32`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_u32) - [`char::from_digit`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.from_digit) - [`char::to_digit`] (https://doc.rust-lang.org/stable/std/primitive.char.html#method.to_digit) - [`core::char::from_u32`] (https://doc.rust-lang.org/stable/core/char/fn.from_u32.html) - [`core::char::from_digit`] (https://doc.rust-lang.org/stable/core/char/fn.from_digit.html) Compatibility Notes ------------------- - [The layout of `repr(Rust)` types now groups m\*2^n-sized fields with equivalently aligned ones.] (rust-lang/rust#102750) This is intended to be an optimization, but it is also known to increase type sizes in a few cases for the placement of enum tags. As a reminder, the layout of `repr(Rust)` types is an implementation detail, subject to change. - [0.5 now rounds to 0 when formatted to 0 decimal places.] (rust-lang/rust#102935) This makes it consistent with the rest of floating point formatting that rounds ties toward even digits. - [Chains of `&&` and `||` will now drop temporaries from their sub-expressions in evaluation order, left-to-right.] (rust-lang/rust#103293) Previously, it was "twisted" such that the _first_ expression dropped its temporaries _last_, after all of the other expressions dropped in order. - [Underscore suffixes on string literals are now a hard error.] (rust-lang/rust#103914) This has been a future-compatibility warning since 1.20.0. - [Stop passing `-export-dynamic` to `wasm-ld`.] (rust-lang/rust#105405) - [`main` is now mangled as `__main_void` on `wasm32-wasi`.] (rust-lang/rust#105468) - [Cargo now emits an error if there are multiple registries in the configuration with the same index URL.] (rust-lang/cargo#10592) Internal Changes ---------------- These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Rewrite LLVM's archive writer in Rust.] (rust-lang/rust#97485)

remove requirement of T: Debug from Weak<T>

ca7297b

rust-highfive assigned kennytm Oct 26, 2021

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dwrensha mentioned this pull request Sep 23, 2023

encountered a fresh type during canonicalization #103626

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compiler-errors mentioned this pull request Nov 4, 2023

ICE: <_ as MyTrait<Ty1>>::Out where trait MyTrait<T: OtherTrait<Assoc = Self>>> on nightly #117577

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Loosen the bound on the Debug implementation of Weak. #90291

Loosen the bound on the Debug implementation of Weak. #90291

geeklint commented Oct 26, 2021

rust-highfive commented Oct 26, 2021

scottmcm Oct 26, 2021

kennytm Oct 27, 2021

joshtriplett commented Oct 30, 2021

rfcbot commented Oct 30, 2021 •

edited by BurntSushi

BurntSushi commented Oct 31, 2021

geeklint commented Oct 31, 2021

BurntSushi commented Oct 31, 2021

geeklint commented Oct 31, 2021

BurntSushi commented Nov 1, 2021

yaahc commented Dec 10, 2021

geeklint commented Dec 11, 2021

joshtriplett commented Dec 22, 2021 •

edited

m-ou-se commented Jan 19, 2022

yaahc commented Feb 11, 2022

m-ou-se commented Feb 16, 2022

BurntSushi commented Feb 23, 2022

geeklint commented Mar 16, 2022

carbotaniuman commented Jul 15, 2022

thomcc commented Aug 25, 2022

BurntSushi commented Dec 28, 2022

rfcbot commented Dec 28, 2022

rfcbot commented Jan 7, 2023

dtolnay commented Jan 7, 2023

bors commented Jan 7, 2023

bors commented Jan 8, 2023

bors commented Jan 9, 2023

rust-timer commented Jan 9, 2023

Loosen the bound on the Debug implementation of Weak. #90291

Loosen the bound on the Debug implementation of Weak. #90291

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geeklint commented Oct 26, 2021

rust-highfive commented Oct 26, 2021

scottmcm Oct 26, 2021

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kennytm Oct 27, 2021

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joshtriplett commented Oct 30, 2021

rfcbot commented Oct 30, 2021 • edited by BurntSushi

BurntSushi commented Oct 31, 2021

geeklint commented Oct 31, 2021

BurntSushi commented Oct 31, 2021

geeklint commented Oct 31, 2021

BurntSushi commented Nov 1, 2021

yaahc commented Dec 10, 2021

geeklint commented Dec 11, 2021

joshtriplett commented Dec 22, 2021 • edited

m-ou-se commented Jan 19, 2022

yaahc commented Feb 11, 2022

m-ou-se commented Feb 16, 2022

BurntSushi commented Feb 23, 2022

geeklint commented Mar 16, 2022

carbotaniuman commented Jul 15, 2022

thomcc commented Aug 25, 2022

BurntSushi commented Dec 28, 2022

rfcbot commented Dec 28, 2022

rfcbot commented Jan 7, 2023

dtolnay commented Jan 7, 2023

bors commented Jan 7, 2023

bors commented Jan 8, 2023

bors commented Jan 9, 2023

rust-timer commented Jan 9, 2023

Overall result: ✅ improvements - no action needed

Instruction count

Max RSS (memory usage)

Cycles

rfcbot commented Oct 30, 2021 •

edited by BurntSushi

joshtriplett commented Dec 22, 2021 •

edited