Stream: t-compiler

Topic: pre-meeting triage 2019-12-05 #54818


pnkfelix (Dec 05 2019 at 13:39, on Zulip):

I will be doing pre-triage in this channel.

pnkfelix (Dec 05 2019 at 13:43, on Zulip):

first up, unprioritized nominations

pnkfelix (Dec 05 2019 at 13:43, on Zulip):

unpri nom 1/10: "internal compiler error: src/librustc/ty/subst.rs:610: type parameter E/#1 (E/1) out of range when substituting (root type=Some(E)) substs=[]" #67037

pnkfelix (Dec 05 2019 at 13:43, on Zulip):

has PR. tagging P-high removing nomination.

centril (Dec 05 2019 at 13:44, on Zulip):

feel free to review-steal-drive-by-r+ :P

pnkfelix (Dec 05 2019 at 13:44, on Zulip):

unpri nom 2/10: "attempted .def_id() on invalid res: Err in rustdoc for pub(restricted) struct fields using derive helper macros" #67006

pnkfelix (Dec 05 2019 at 13:45, on Zulip):

triage: petrochenkov self-assigned. P-high, removing nomination.

pnkfelix (Dec 05 2019 at 13:46, on Zulip):

unpri nom 3/10: "libarena::TypedArena::alloc_from_iter does not allow for recursive allocations" #67001

pnkfelix (Dec 05 2019 at 13:46, on Zulip):

holy cow

pnkfelix (Dec 05 2019 at 13:47, on Zulip):

If [...], the allocation goes in the fast path. In that case, the allocation for the range and the recursive allocations get interlaced. The returned pointers are wrong, and valid objects get overwritten. This can lead to undropped objects and infinite loops.

simulacrum (Dec 05 2019 at 13:48, on Zulip):

(we have a fix in the pipeline, so I think this is p-low at this point -- maybe a performance optimization)

pnkfelix (Dec 05 2019 at 13:48, on Zulip):

P-low? the fact it sounds like it has soundness issues makes it P-high to me

simulacrum (Dec 05 2019 at 13:48, on Zulip):

because https://github.com/rust-lang/rust/pull/67003/ will fix it

pnkfelix (Dec 05 2019 at 13:48, on Zulip):

(things with fixes in pipeline can and do get P-high all the time. I use P-labels as severity metrics)

simulacrum (Dec 05 2019 at 13:48, on Zulip):

but sure, p-high seems fine

pnkfelix (Dec 05 2019 at 13:48, on Zulip):

(not as "is this getting enough attention metrics")

pnkfelix (Dec 05 2019 at 13:49, on Zulip):

but arguably this is something that should change. (not today though!)

centril (Dec 05 2019 at 13:50, on Zulip):

I-unsound is its own severity metric; basically it's the worst severity ^^

pnkfelix (Dec 05 2019 at 13:50, on Zulip):

its also a T-libs issue, not a T-compiler one, based on PR #67003

simulacrum (Dec 05 2019 at 13:50, on Zulip):

well, libarena isn't t-libs

simulacrum (Dec 05 2019 at 13:50, on Zulip):

i.e., it's owned by compiler team

pnkfelix (Dec 05 2019 at 13:50, on Zulip):

oh .... right

pnkfelix (Dec 05 2019 at 13:51, on Zulip):

we should check if the crates.io TypedArena has the same problem.

centril (Dec 05 2019 at 13:52, on Zulip):

well, libarena isn't t-libs

maybe this is suggesting that we need to change the folder structure to have src/compiler and src/stdlib/

pnkfelix (Dec 05 2019 at 13:52, on Zulip):

cannot trivially tell if crates.io TypedArena does

centril (Dec 05 2019 at 13:52, on Zulip):

file an issue for deeper investigation :slight_smile:

simulacrum (Dec 05 2019 at 13:52, on Zulip):

does not look like it does

simulacrum (Dec 05 2019 at 13:53, on Zulip):

but unclear, it has vecs as backing store vs. raw ptrs

pnkfelix (Dec 05 2019 at 13:53, on Zulip):

Cc'ed SimonSapin on PR #67003 in any case.

pnkfelix (Dec 05 2019 at 13:54, on Zulip):

oh yeah, maybe it was a from-scratch impl, I cannot remember now

pnkfelix (Dec 05 2019 at 13:58, on Zulip):

unpri nom 4/10: "ICE on rustc 1.41.0-nightly (25d8a9494 2019-11-29) running on x86_64-apple-darwin" #66958

pnkfelix (Dec 05 2019 at 13:59, on Zulip):

triage: has PR. P-high, removing nomination.

pnkfelix (Dec 05 2019 at 13:59, on Zulip):

unpri nom 5/10: "internal compiler error: our vector went away? in proc macro expansion" #66922

pnkfelix (Dec 05 2019 at 14:01, on Zulip):

triage: @estebank has been cc'ed (tho' not yet assigned). P-high, removing nomination.

pnkfelix (Dec 05 2019 at 14:02, on Zulip):

unpri nom 6/10: "Emscripten builds broken on nightly? (Linking errors in fresh "hello world" crate)" #66916

pnkfelix (Dec 05 2019 at 14:02, on Zulip):

needs reduction to MCVE

pnkfelix (Dec 05 2019 at 14:03, on Zulip):

@centril should we rename the label E-needs-mcve to E-needs-reduction-to-mcve? I am not sure if enough people know the MCVE acronym at a glance.

pnkfelix (Dec 05 2019 at 14:04, on Zulip):

I suppose in some cases E-needs-mcve is given when we don't even have anything to start a reduction from ...?

centril (Dec 05 2019 at 14:04, on Zulip):

doesn't the label have a description?

pnkfelix (Dec 05 2019 at 14:04, on Zulip):

(though I think in practice we usually only use the label when we actually do have something to start with)

pnkfelix (Dec 05 2019 at 14:04, on Zulip):

label has description, yes

pnkfelix (Dec 05 2019 at 14:04, on Zulip):

but I am musing about whether that is enough

centril (Dec 05 2019 at 14:04, on Zulip):

I'm not opposed but meh :slight_smile:

pnkfelix (Dec 05 2019 at 14:04, on Zulip):

its just a thought

pnkfelix (Dec 05 2019 at 14:05, on Zulip):

anyway

pnkfelix (Dec 05 2019 at 14:05, on Zulip):

seems like this is something we should track down

pnkfelix (Dec 05 2019 at 14:05, on Zulip):

triage #66916 : P-high, removing nomination.

pnkfelix (Dec 05 2019 at 14:09, on Zulip):

unpri nom 7/10: "rls no longer builds after rust-lang/rust#66879" #66885

pnkfelix (Dec 05 2019 at 14:09, on Zulip):

triage: P-medium, removing nomination.

pnkfelix (Dec 05 2019 at 14:10, on Zulip):

unpri nom 8/10: "ICE on closure typeck" #66868

pnkfelix (Dec 05 2019 at 14:11, on Zulip):

not clear if this is a regression or a long-standing bug

pnkfelix (Dec 05 2019 at 14:11, on Zulip):

triage: P-high, at least to identify whether this is a long-standing bug or a stable-to-stable regression. Removing nomination.

pnkfelix (Dec 05 2019 at 14:12, on Zulip):

unpri nom 9/10: "ICE when cargo doc on lexical-core: attempted .def_id() on invalid res: Err" #64705

pnkfelix (Dec 05 2019 at 14:13, on Zulip):

duplicate of #67006, or perhaps this was reduced down to that?

pnkfelix (Dec 05 2019 at 14:13, on Zulip):

ah comment says #67006 is similar but newer regression

pnkfelix (Dec 05 2019 at 14:14, on Zulip):

triage: P-high, removing nomination

pnkfelix (Dec 05 2019 at 14:14, on Zulip):

unpri nom 10/10: "Linking issue with Rust 1.37.0" #64340

pnkfelix (Dec 05 2019 at 14:15, on Zulip):

cue Sideshow Bob gif of stepping on rakes

pnkfelix (Dec 05 2019 at 14:17, on Zulip):

seems like PR #59752 was nominated for discussion for a potential revert to fix this and other issues

pnkfelix (Dec 05 2019 at 14:17, on Zulip):

I need to double check if our meeting agenda links include nominated merged PR's

pnkfelix (Dec 05 2019 at 14:18, on Zulip):

nope, currently it does not

pnkfelix (Dec 05 2019 at 14:20, on Zulip):

I'll add this one manually and later try to look into whether we can fix that (so that even closed can be nominated)

pnkfelix (Dec 05 2019 at 14:21, on Zulip):

anyway, triage #64340: P-high. Leaving nomination label

pnkfelix (Dec 05 2019 at 14:24, on Zulip):

next list, unprioritized beta-regressions ... there aren't any.

pnkfelix (Dec 05 2019 at 14:24, on Zulip):

next list, unprioritized nightly regressions ... there aren't any

pnkfelix (Dec 05 2019 at 14:25, on Zulip):

next list: nominated issues, trying to find cases that do not need to remain nominated.

pnkfelix (Dec 05 2019 at 14:29, on Zulip):

I'm going retag "floating point to integer casts can cause undefined behaviour" #10184 as solely T-lang: I think the issues to be resolved there are semantic choices about what float as int means

pnkfelix (Dec 05 2019 at 14:30, on Zulip):

(i.e. whether we are willing to let it have a panicking semantics or not, whether we are willing to let it have a freeze-based underspecification or not, etc)

pnkfelix (Dec 05 2019 at 14:30, on Zulip):

these are questions better aimed at the T-lang team, not T-compiler, at least for the initial discussion, IMO

centril (Dec 05 2019 at 14:31, on Zulip):

I thought we were going with saturation

centril (Dec 05 2019 at 14:31, on Zulip):

and only the implementation remained

pnkfelix (Dec 05 2019 at 14:32, on Zulip):

the dialogue on the issue does not make that clear to me

centril (Dec 05 2019 at 14:32, on Zulip):

guess we need a clearer decision then?

pnkfelix (Dec 05 2019 at 14:33, on Zulip):

I hate github's handling of long comment threads so much

pnkfelix (Dec 05 2019 at 14:33, on Zulip):

like: why does "load more ..." not load from both directions ???

pnkfelix (Dec 05 2019 at 14:34, on Zulip):

if I want to see more of the recent discussion, I have to repeatedly unfold everything from the beginning? Really? Really?

centril (Dec 05 2019 at 14:34, on Zulip):

i know right

centril (Dec 05 2019 at 14:34, on Zulip):

I would love a "show me every comment, I really mean it"-button

pnkfelix (Dec 05 2019 at 14:36, on Zulip):

issue "under latest MinGW, cannot link with C code using stdout" #47048 remains nominated. Despite my effort to draw attention to it last week, I'm not sure I can remove the nomination label yet, given the radio silence that resulted then.

pnkfelix (Dec 05 2019 at 14:37, on Zulip):

@Jonas Schievink you added T-infra to issue #53454 a week ago. Is the plan to resolve #47048 via that means? Does this "just" turn into an infrastructural issue?

pnkfelix (Dec 05 2019 at 14:37, on Zulip):

(or is it something that requires attention from both T-compiler and T-infra ?)

pnkfelix (Dec 05 2019 at 14:38, on Zulip):

likewise for "COPYRIGHT file is wildly out of date" #63232

pnkfelix (Dec 05 2019 at 14:40, on Zulip):

@centril is issue #65860 a T-lang thing or a T-compiler thing at this point? The PR that caused problems for RalfJ was reverted; does that mean we can un-nominate #63232 #65860 from T-compiler issues?

Jonas Schievink (Dec 05 2019 at 14:40, on Zulip):

I added T-infra to address the first part in the issue: "We package these files in "rust-mingw" component instead of current "rust-std" component in win-gnu builds."

Jonas Schievink (Dec 05 2019 at 14:40, on Zulip):

I think someone mentioned that this is done now?

centril (Dec 05 2019 at 14:41, on Zulip):

@pnkfelix what's the relation btw those PRs?

pnkfelix (Dec 05 2019 at 14:41, on Zulip):

shoot that was a typo

centril (Dec 05 2019 at 14:41, on Zulip):

the conditional compilation thing is waiting for me to do a write-up

pnkfelix (Dec 05 2019 at 14:41, on Zulip):

I meant to reference #65860 in both cases

centril (Dec 05 2019 at 14:42, on Zulip):

you can un-nominate and I'll renominate when I'm ready

pnkfelix (Dec 05 2019 at 14:42, on Zulip):

sounds great, thanks

centril (Dec 05 2019 at 14:42, on Zulip):

:slight_smile:

pnkfelix (Dec 05 2019 at 14:42, on Zulip):

I think I will do the same for "improper_ctypes fires for &mut T, &T, *const T and *mut T (when T: Sized)" #66220

pnkfelix (Dec 05 2019 at 14:43, on Zulip):

(a similar situation where we have done an eager revert and now await follow-up work for a more nuanced fix

davidtwco (Dec 05 2019 at 14:44, on Zulip):

I hope to get to that after next week.

pnkfelix (Dec 05 2019 at 14:45, on Zulip):

you can un-nominate and I'll renominate when I'm ready

do you want me to assign you to the issue so that it does not get lost?

pnkfelix (Dec 05 2019 at 14:45, on Zulip):

(and to represent the idea that you have pending work that you intend to do on it)

centril (Dec 05 2019 at 14:47, on Zulip):

@davidtwco could I interest you in review-stealing https://github.com/rust-lang/rust/pull/67044 so it's ready before we discuss beta noms? :P

davidtwco (Dec 05 2019 at 14:48, on Zulip):

@centril I’ll do my best, on a train so internet isn’t guaranteed.

centril (Dec 05 2019 at 14:49, on Zulip):

aight, I'll take it :slight_smile:

Esteban Küber (Dec 05 2019 at 14:49, on Zulip):

Done @centril

centril (Dec 05 2019 at 14:49, on Zulip):

heh =P

Esteban Küber (Dec 05 2019 at 14:49, on Zulip):

Done @centril

Esteban Küber (Dec 05 2019 at 14:49, on Zulip):

Boarding PR review FTW

pnkfelix (Dec 05 2019 at 14:50, on Zulip):

Regarding this nomination: "Regression in Error conversion from Infallible" #66757, the most relevant comment is here: https://github.com/rust-lang/rust/issues/66757#issuecomment-559771169

Esteban Küber (Dec 05 2019 at 14:50, on Zulip):

image-b8d386d4-041c-45d4-bd4a-29bdbf7203c5.jpg

centril (Dec 05 2019 at 14:51, on Zulip):

(re. never type, I'm inclined towards 1. right now)

pnkfelix (Dec 05 2019 at 14:52, on Zulip):

why not 7 ?

pnkfelix (Dec 05 2019 at 14:52, on Zulip):

(reverting stabilization)

centril (Dec 05 2019 at 14:52, on Zulip):

that would be the second time we've reverted !

pnkfelix (Dec 05 2019 at 14:53, on Zulip):

that ... sounds like some sort of sunk cost fallacy to me ?

centril (Dec 05 2019 at 14:54, on Zulip):

I think the feature is fine as-is, never_type_fallback could make it better in the future, and the regressions are allowed under RFC 1122

pnkfelix (Dec 05 2019 at 14:56, on Zulip):

@eddyb are you around today? I don't want to put PR #66838 "[WIP] [DO NOT MERGE] combine #66020 and #66821" on the table for discussion if you aren't around to provide further background/context.

eddyb (Dec 05 2019 at 14:57, on Zulip):

oh hi

eddyb (Dec 05 2019 at 14:57, on Zulip):

@pnkfelix I think @nikomatsakis is up to speed on the context, and I'll be present

eddyb (Dec 05 2019 at 14:59, on Zulip):

he's happy with landing half of those changes, which means we can probably spend a lot more time thinking about the "skip unnecessary work in WF" part (which is scarier soundness-wise)

pnkfelix (Dec 05 2019 at 15:00, on Zulip):

@centril "Const generic ICE: constant in type had an ignored error: TooGeneric" #66962 is nominated and tagged P-medium ?

pnkfelix (Dec 05 2019 at 15:00, on Zulip):

what do you want T-compiler to discuss for nomination?

centril (Dec 05 2019 at 15:00, on Zulip):

someone should fix it

centril (Dec 05 2019 at 15:00, on Zulip):

P-medium is my suggestion

pnkfelix (Dec 05 2019 at 15:01, on Zulip):

isn't that the case for all bugs? (that someone should fix it)

centril (Dec 05 2019 at 15:01, on Zulip):

yes, well, we should find someone to fix it like we do

pnkfelix (Dec 05 2019 at 15:01, on Zulip):

I'll go ahead and advertise it on the channel.

pnkfelix (Dec 05 2019 at 15:01, on Zulip):

but then remove the nomination label

pnkfelix (Dec 05 2019 at 15:01, on Zulip):

because ... I don't think there's anything to actually discuss there?

centril (Dec 05 2019 at 15:02, on Zulip):

well maybe you think it should be P-high :slight_smile:

centril (Dec 05 2019 at 15:02, on Zulip):

that's up for discussion :P

Last update: Jan 21 2020 at 08:25UTC