Skip to content

Commit 97dae01

Browse files
committed
Add T-compiler meeting notes 10/23
1 parent 6ac7653 commit 97dae01

File tree

4 files changed

+986
-0
lines changed

4 files changed

+986
-0
lines changed
Lines changed: 241 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,241 @@
1+
---
2+
tags: weekly, rustc
3+
type: docs
4+
---
5+
6+
# T-compiler Meeting Agenda 2023-10-05
7+
8+
## Announcements
9+
10+
- :loudspeaker: Today Oct, 5th release of Rust stable 1.73
11+
- [Compiler Team Steering Meeting - P-high review](https://www.google.com/calendar/event?eid=NWk1dW9uc2dkM2dxZG1uZ21xMmo4Mzcxa2wgNnU1cnJ0Y2U2bHJ0djA3cGZpM2RhbWdqdXNAZw) at <time:2023-10-06T10:00:00-04:00>
12+
- Reminder: if you see a PR/issue that seems like there might be legal implications due to copyright/IP/etc, please let us know (or at least message @_**davidtwco** or @_**Wesley Wiser** so we can pass it along).
13+
14+
### Other WG meetings ([calendar link](https://calendar.google.com/calendar/embed?src=6u5rrtce6lrtv07pfi3damgjus%40group.calendar.google.com))
15+
- [wg-async weekly](https://www.google.com/calendar/event?eid=ajVtNGowYjlzdDNhM2VwZG9vNjg4OTlzNDBfMjAyMzEwMDVUMTYwMDAwWiA2dTVycnRjZTZscnR2MDdwZmkzZGFtZ2p1c0Bn) at <time:2023-10-05T12:00:00-04:00>
16+
- [AFIT/RPITIT Impl Triage](https://www.google.com/calendar/event?eid=N2VsaWszdm9rY3NhdDF1MjdyMjVqajNpcWVfMjAyMzEwMDVUMjAwMDAwWiA2dTVycnRjZTZscnR2MDdwZmkzZGFtZ2p1c0Bn) at <time:2023-10-05T16:00:00-04:00>
17+
- [Stable MIR Weekly Meeting](https://www.google.com/calendar/event?eid=N25kMTM2Z3NxbXJjNTE5ZWJpM2traHNpa21fMjAyMzEwMDZUMTUwMDAwWiA2dTVycnRjZTZscnR2MDdwZmkzZGFtZ2p1c0Bn) at <time:2023-10-06T11:00:00-04:00>
18+
19+
## MCPs/FCPs
20+
21+
- New MCPs (take a look, see if you like them!)
22+
- No new proposals this time.
23+
- Old MCPs (stale MCP might be closed as per [MCP procedure](https://forge.rust-lang.org/compiler/mcp.html#when-should-major-change-proposals-be-closed))
24+
- None at this time
25+
- Old MCPs (not seconded, take a look)
26+
- "Consistently use "region" terminology in later stages of the compiler" [compiler-team#634](https://github.com/rust-lang/compiler-team/issues/634) (last review activity: 4 months ago)
27+
- "Add a new `--build-id` flag to rustc" [compiler-team#635](https://github.com/rust-lang/compiler-team/issues/635) (last review activity: 4 months ago)
28+
- "Simplify and improve explicitness of the check-cfg syntax" [compiler-team#636](https://github.com/rust-lang/compiler-team/issues/636) (last review activity: about 0 days ago)
29+
- "Add support for visionOS targets" [compiler-team#642](https://github.com/rust-lang/compiler-team/issues/642) (last review activity: about 33 days ago)
30+
- "Match the behavior of `strip` and `split-debuginfo` across platforms" [compiler-team#669](https://github.com/rust-lang/compiler-team/issues/669) (last review activity: about 30 days ago)
31+
- Pending FCP requests (check your boxes!)
32+
- "Retire the mailing list and make all decisions on zulip" [compiler-team#649](https://github.com/rust-lang/compiler-team/issues/649)
33+
- " Add `type` field to distinguish json diagnostic outputs" [compiler-team#673](https://github.com/rust-lang/compiler-team/issues/673)
34+
- "Stabilize `--json=unused-externs(-silent)`" [compiler-team#674](https://github.com/rust-lang/compiler-team/issues/674)
35+
- "Tracking issue for dyn upcasting coercion" [rust#65991](https://github.com/rust-lang/rust/issues/65991)
36+
- "Support overriding `warnings` level for a specific lint via command line" [rust#113307](https://github.com/rust-lang/rust/pull/113307)
37+
- "Update Windows platform support" [rust#115141](https://github.com/rust-lang/rust/pull/115141)
38+
- "Remove support for compiler plugins." [rust#116412](https://github.com/rust-lang/rust/pull/116412)
39+
- Things in FCP (make sure you're good with it)
40+
- "Add a blanket flag to enable/disable codegen UB checks" [compiler-team#625](https://github.com/rust-lang/compiler-team/issues/625)
41+
- "Report all lints, even if other errors already occurred." [compiler-team#633](https://github.com/rust-lang/compiler-team/issues/633)
42+
- "Add tidy rule against `issue-[0-9]+.rs` tests" [compiler-team#658](https://github.com/rust-lang/compiler-team/issues/658)
43+
- "Add infrastructure to "compute the ABI of a Rust type, described as a C type"" [compiler-team#672](https://github.com/rust-lang/compiler-team/issues/672)
44+
- "Stabilize `--json=unused-externs(-silent)`" [compiler-team#674](https://github.com/rust-lang/compiler-team/issues/674)
45+
- "Have `rustc` produce a local log of execution metrics" [compiler-team#679](https://github.com/rust-lang/compiler-team/issues/679)
46+
- Accepted MCPs
47+
- "Add support for Zephyr OS" [compiler-team#629](https://github.com/rust-lang/compiler-team/issues/629)
48+
- "Add illumos Tier3 targets" [compiler-team#644](https://github.com/rust-lang/compiler-team/issues/644)
49+
- "Add option to pass environment variables" [compiler-team#653](https://github.com/rust-lang/compiler-team/issues/653)
50+
- "Condemn `asmjs-unknown-emscripten` to push a boulder up a hill for eternity" [compiler-team#668](https://github.com/rust-lang/compiler-team/issues/668)
51+
- "Allow overriding default codegen backend on a per-target basis" [compiler-team#670](https://github.com/rust-lang/compiler-team/issues/670)
52+
- "Change how closure and generator types are printed to avoid clash with slice types" [compiler-team#675](https://github.com/rust-lang/compiler-team/issues/675)
53+
- "Offload dep graph encoding to a thread" [compiler-team#677](https://github.com/rust-lang/compiler-team/issues/677)
54+
- Finalized FCPs (disposition merge)
55+
- "stabilize combining +bundle and +whole-archive link modifiers" [rust#113301](https://github.com/rust-lang/rust/pull/113301)
56+
57+
### WG checkins
58+
59+
- @_*WG-rustc-dev-guide* by @**Santiago Pastorino** and @**Yuki Okushi|217081** ([previous checkin](https://hackmd.io/team/rust-compiler-team?nav=overview)):
60+
> Checkin text
61+
62+
- Impl Trait initiative by @**oli** ([previous checkin](https://hackmd.io/team/rust-compiler-team?nav=overview)):
63+
> Checkin text
64+
65+
## Backport nominations
66+
67+
[T-compiler stable](https://github.com/rust-lang/rust/issues?q=is%3Aall+label%3Abeta-nominated+-label%3Abeta-accepted+label%3AT-compiler) / [T-compiler beta](https://github.com/rust-lang/rust/issues?q=is%3Aall+label%3Astable-nominated+-label%3Astable-accepted+label%3AT-compiler)
68+
- No beta nominations for `T-compiler` this time.
69+
- No stable nominations for `T-compiler` this time.
70+
71+
## PRs S-waiting-on-team
72+
73+
[T-compiler](https://github.com/rust-lang/rust/pulls?q=is%3Aopen+label%3AS-waiting-on-team+label%3AT-compiler)
74+
- Other issues [in progress or waiting on other teams](https://hackmd.io/XYr1BrOWSiqCrl8RCWXRaQ)
75+
76+
## Issues of Note
77+
78+
### Short Summary
79+
80+
- [0 T-compiler P-critical issues](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-compiler+label%3AP-critical)
81+
- [0 of those are unassigned](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-compiler+label%3AP-critical+no%3Aassignee)
82+
- [61 T-compiler P-high issues](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-compiler+label%3AP-high)
83+
- [36 of those are unassigned](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AT-compiler+label%3AP-high+no%3Aassignee)
84+
- [0 P-critical, 0 P-high, 1 P-medium, 1 P-low regression-from-stable-to-beta](https://github.com/rust-lang/rust/labels/regression-from-stable-to-beta)
85+
- [0 P-critical, 2 P-high, 2 P-medium, 2 P-low regression-from-stable-to-nightly](https://github.com/rust-lang/rust/labels/regression-from-stable-to-nightly)
86+
- [0 P-critical, 41 P-high, 100 P-medium, 19 P-low regression-from-stable-to-stable](https://github.com/rust-lang/rust/labels/regression-from-stable-to-stable)
87+
88+
### P-critical
89+
90+
[T-compiler](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AP-critical+label%3AT-compiler)
91+
- No `P-critical` issues for `T-compiler` this time.
92+
93+
[T-types](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AP-critical+label%3AT-types)
94+
- No `P-critical` issues for `T-types` this time.
95+
96+
[T-rustdoc](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AP-critical+label%3AT-rustdoc)
97+
- No `P-critical` issues for `T-rustdoc` this time.
98+
99+
### P-high regressions
100+
101+
[P-high beta regressions](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3Aregression-from-stable-to-beta+label%3AP-high+-label%3AT-infra+-label%3AT-libs+-label%3AT-libs-api+-label%3AT-release+-label%3AT-rustdoc+-label%3AT-core)
102+
- No `P-high` beta regressions this time.
103+
104+
[Unassigned P-high nightly regressions](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3Aregression-from-stable-to-nightly+label%3AP-high+no%3Aassignee+-label%3AT-infra+-label%3AT-libs+-label%3AT-libs-api+-label%3AT-release+-label%3AT-rustdoc+-label%3AT-core+)
105+
- "ICE: "no errors encountered even though `delay_span_bug` issued" on tantivy v0.21 in release mode" [rust#116333](https://github.com/rust-lang/rust/issues/116333)
106+
- PR [rust#116415](https://github.com/rust-lang/rust/pull/116415) should take care of that (among other similar reported regressions) ([comment](https://github.com/rust-lang/rust/pull/116415#issuecomment-1746692465))
107+
- PR authored by @**Oguz** (thanks), review in progress
108+
109+
## Performance logs
110+
111+
> [triage logs for 2023-10-03](https://github.com/rust-lang/rustc-perf/blob/master/triage/2023-10-03.md)
112+
113+
A week completely free of pure regressions! The compiler has definitely come out of this week a decent amount faster and less memory hungry than before with the large gain coming from building the compiler with a single CGU on x64 Linux. This not only allows LLVM to do more optimizations across the entire compiler, but should hopefully also result in less non-deterministic performance regressions in the future. This improvement largely comes only at the expense of a few more minutes spent when bootstrapping the compiler.
114+
115+
Triage done by **@rylev**.
116+
Revision range: [27b4eb..9998f4](https://perf.rust-lang.org/?start=27b4eb96d13106332d511be2ea6d0c008a57aa6e&end=9998f4add08c3d09c82e00975cf3a293b30160ec&absolute=false&stat=instructions%3Au)
117+
118+
**Summary**:
119+
120+
| (instructions:u) | mean | range | count |
121+
|:------------------------:|:-----:|:--------------:|:-----:|
122+
| Regressions (primary) | 1.0% | [0.3%, 6.1%] | 41 |
123+
| Regressions (secondary) | 2.0% | [0.9%, 7.8%] | 21 |
124+
| Improvements (primary) | -1.3% | [-5.1%, -0.2%] | 134 |
125+
| Improvements (secondary) | -1.8% | [-6.9%, -0.2%] | 175 |
126+
| All (primary) | -0.8% | [-5.1%, 6.1%] | 175 |
127+
128+
129+
0 Regressions, 2 Improvements, 4 Mixed; 0 of them in rollups
130+
74 artifact comparisons made in total
131+
132+
#### Regressions
133+
134+
135+
#### Improvements
136+
137+
rustdoc: speed up processing of cross-crate fns to fix a perf regression [#116195](https://github.com/rust-lang/rust/pull/116195) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=177091258c039398d30137b52e1c575a98aa7597&end=5282e5e120128ba589728ee4bcb4f18511ba9fb0&stat=instructions:u)
138+
139+
| (instructions:u) | mean | range | count |
140+
|:------------------------:|:-----:|:--------------:|:-----:|
141+
| Regressions (primary) | - | - | 0 |
142+
| Regressions (secondary) | - | - | 0 |
143+
| Improvements (primary) | -0.3% | [-0.5%, -0.2%] | 6 |
144+
| Improvements (secondary) | -0.6% | [-0.8%, -0.3%] | 11 |
145+
| All (primary) | -0.3% | [-0.5%, -0.2%] | 6 |
146+
147+
148+
Cleanup number handling in match exhaustiveness [#116281](https://github.com/rust-lang/rust/pull/116281) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=51ddc7467978e265d2004d58980580293734ca93&end=e0d7ed1f453fb54578cc96dfea859b0e7be15016&stat=instructions:u)
149+
150+
| (instructions:u) | mean | range | count |
151+
|:------------------------:|:-----:|:--------------:|:-----:|
152+
| Regressions (primary) | - | - | 0 |
153+
| Regressions (secondary) | - | - | 0 |
154+
| Improvements (primary) | -0.7% | [-1.5%, -0.3%] | 3 |
155+
| Improvements (secondary) | - | - | 0 |
156+
| All (primary) | -0.7% | [-1.5%, -0.3%] | 3 |
157+
158+
159+
#### Mixed
160+
161+
Don't use a thread to load the dep graph [#116109](https://github.com/rust-lang/rust/pull/116109) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=d23062b5be6bbf5be15226c7f497c89cf7d3d6e1&end=8bf0dec101dc458a411401a826994006abd2f022&stat=instructions:u)
162+
163+
| (instructions:u) | mean | range | count |
164+
|:------------------------:|:-----:|:--------------:|:-----:|
165+
| Regressions (primary) | 0.8% | [0.5%, 1.1%] | 2 |
166+
| Regressions (secondary) | 0.5% | [0.1%, 1.2%] | 3 |
167+
| Improvements (primary) | -0.2% | [-0.3%, -0.2%] | 4 |
168+
| Improvements (secondary) | - | - | 0 |
169+
| All (primary) | 0.1% | [-0.3%, 1.1%] | 6 |
170+
- A very small regression that basically results in net zero change to performance.
171+
172+
173+
Build `rustc` with a single CGU on x64 Linux [#115554](https://github.com/rust-lang/rust/pull/115554) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=c16823d757b376f90c5f5cbd542ce83235befbc4&end=871407a0341262d2a86703ca43b449d35fa5f236&stat=instructions:u)
174+
175+
| (instructions:u) | mean | range | count |
176+
|:------------------------:|:-----:|:--------------:|:-----:|
177+
| Regressions (primary) | 0.8% | [0.3%, 2.6%] | 39 |
178+
| Regressions (secondary) | 1.6% | [0.7%, 2.5%] | 23 |
179+
| Improvements (primary) | -1.2% | [-3.9%, -0.2%] | 89 |
180+
| Improvements (secondary) | -1.6% | [-3.5%, -0.4%] | 124 |
181+
| All (primary) | -0.6% | [-3.9%, 2.6%] | 128 |
182+
- The change is overwhelmingly positive (especially when taking other measures like max RSS and artifact size) making the small regressions acceptable
183+
- Take a [look at cycles](https://perf.rust-lang.org/compare.html?start=c16823d757b376f90c5f5cbd542ce83235befbc4&end=871407a0341262d2a86703ca43b449d35fa5f236&stat=cycles%3Au) for a nearly completely regression free view of the positive nature of this change.
184+
185+
186+
Rebased: Mark drop calls in landing pads cold instead of noinline [#102099](https://github.com/rust-lang/rust/pull/102099) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=5333b878c8bc1c4267a67ea3682663629e47541a&end=2e5a9dd6c9eaa42f0684b4b760bd68fc27cbe51b&stat=instructions:u)
187+
188+
| (instructions:u) | mean | range | count |
189+
|:------------------------:|:-----:|:--------------:|:-----:|
190+
| Regressions (primary) | 1.5% | [0.3%, 5.9%] | 12 |
191+
| Regressions (secondary) | 2.7% | [0.4%, 7.7%] | 5 |
192+
| Improvements (primary) | -0.5% | [-4.5%, -0.2%] | 78 |
193+
| Improvements (secondary) | -0.9% | [-6.9%, -0.1%] | 65 |
194+
| All (primary) | -0.2% | [-4.5%, 5.9%] | 90 |
195+
- Largely positive with a few large regressions caused by more time spent in LLVM. This seems to be expected and acceptable.
196+
197+
198+
Make subtyping explicit in MIR [#115025](https://github.com/rust-lang/rust/pull/115025) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=9998f4add08c3d09c82e00975cf3a293b30160ec&end=eb0f3ed59c6508a37c6598bc9762987f053993a7&stat=instructions:u)
199+
200+
| (instructions:u) | mean | range | count |
201+
|:------------------------:|:-----:|:--------------:|:-----:|
202+
| Regressions (primary) | 0.6% | [0.4%, 0.8%] | 2 |
203+
| Regressions (secondary) | 0.5% | [0.1%, 1.1%] | 17 |
204+
| Improvements (primary) | -0.5% | [-0.6%, -0.5%] | 2 |
205+
| Improvements (secondary) | -0.5% | [-0.5%, -0.5%] | 1 |
206+
| All (primary) | 0.0% | [-0.6%, 0.8%] | 4 |
207+
- Small regression that is basically only seen in some secondary benchmarks. Unlikely to be worth deep investigation.
208+
209+
210+
## Nominated Issues
211+
212+
[T-compiler](https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AI-compiler-nominated)
213+
- No I-compiler-nominated issues this time.
214+
215+
[RFC](https://github.com/rust-lang/rfcs/issues?q=is%3Aopen+label%3AI-compiler-nominated)
216+
- No I-compiler-nominated RFCs this time.
217+
218+
### Oldest PRs waiting for review
219+
220+
[T-compiler](https://github.com/rust-lang/rust/pulls?q=is%3Apr+is%3Aopen+sort%3Aupdated-asc+label%3AS-waiting-on-review+draft%3Afalse+label%3AT-compiler)
221+
- "Improve `print_tts`" [rust#114571](https://github.com/rust-lang/rust/pull/114571) (last review activity: about 48 days ago)
222+
- Some review talks with @**Vadim Petrochenkov**, seems this is waiting on him? (see [last comments](https://github.com/rust-lang/rust/pull/114571#issuecomment-1682486307))
223+
- "compiler: be more clear about transparent layout violations" [rust#114015](https://github.com/rust-lang/rust/pull/114015) (last review activity: about 41 days ago)
224+
- cc: @**pnkfelix**
225+
- "Remove -Zfuel." [rust#115293](https://github.com/rust-lang/rust/pull/115293) (last review activity: about 38 days ago)
226+
- *seems* to be ready for a review (though not 100% sure since it receives updates) cc: @**Wesley Wiser**
227+
- "Remove -Zfuel." [rust#115293](https://github.com/rust-lang/rust/pull/115293) (last review activity: about 38 days ago)
228+
- cc: @**Wesley Wiser**
229+
- "Suggest adding `return` if the for semi which can coerce to the fn return type" [rust#115196](https://github.com/rust-lang/rust/pull/115196) (last review activity: about 33 days ago)
230+
- cc @**Esteban Küber**
231+
- "Extract suitable code from rustc_query_impl into a new crate rustc_query_misc" [rust#115118](https://github.com/rust-lang/rust/pull/115118) (last review activity: about 32 days ago)
232+
- probably ready for another round review cc: @**cjgillot**
233+
- "Parse unnamed fields and anonymous structs or unions" [rust#115732](https://github.com/rust-lang/rust/pull/115732) (last review activity: about 24 days ago)
234+
- cc: @**Vadim Petrochenkov**
235+
236+
## Next week's WG checkins
237+
238+
- @_*WG-llvm* by @**nagisa** and @**Nikita Popov**
239+
- @_*WG-mir-opt* by @**oli**
240+
241+
Next meetings' agenda draft: [hackmd link](https://hackmd.io/Eq0n1oBvTaajzXK5WvKPng)

0 commit comments

Comments
 (0)