# Libs Meeting 2024-07-10

###### tags: `Libs Meetings` `Minutes`

**Meeting Link**: https://meet.jit.si/rust-libs-meeting-ujepnbwg2lzqgt6wvrndwimi
**Attendees**: Amanieu, Josh Stone, Josh Triplett, Mara, The 8472

## Agenda

- Triage
- Anything else?

## Triage

### FCPs

2 rust-lang/rust T-libs FCPs

- merge rust.tf/115746 *Print thread ID in panic message if thread name is unknown* - (3 checkboxes left)
- merge rust.tf/123940 *debug\-fmt\-detail option* - (7 checkboxes left)

[wesleywiser (1)](https://rfcbot.rs/fcp/wesleywiser), [thomcc (1)](https://rfcbot.rs/fcp/thomcc), [joshtriplett (1)](https://rfcbot.rs/fcp/joshtriplett), [pnkfelix (1)](https://rfcbot.rs/fcp/pnkfelix), [eddyb (1)](https://rfcbot.rs/fcp/eddyb), [the8472 (1)](https://rfcbot.rs/fcp/the8472), [Amanieu (1)](https://rfcbot.rs/fcp/Amanieu), [cuviper (1)](https://rfcbot.rs/fcp/cuviper), [m-ou-se (2)](https://rfcbot.rs/fcp/m-ou-se)

### (Prioritization Requested) rust.tf/126766 *Nightly regression: \`panic::set\_hook()\` signature incompatible if used with core::panic::PanicInfo*

Looks like the breakage is not widespread.

JoshT: This isn't covered by our 'acceptable breakage' policy, so we'd be deciding to diverge from that. So we should at least relnotes this and ask people to

Amanieu: Let's close as acceptable.

Mara: +1

### (Nominated) rust.tf/127340 *regression: \`RefCell\<LineWriter\<std::io::stdio::StdoutRaw\>\>\` cannot be shared between threads safely*

Amanieu: Acceptable breakage.

JoshT: Not great that it's also not Send.

Mara: It can never be Send, because you can get two lock()s in the same thread, and then you shouldn't send one away to another thread.

The 8472: cargo semver checks for std?

### (Waiting on team) rust.tf/120706 *Initial support for auto traits with default bounds*

Not for this team.

### (Waiting on team) rust.tf/126958 *Stabilize const unchecked conversion from u32 to char*

-> libs-api

### (Regressions) rust.tf/119560 *\`cargo test\` performance regression on Windows on version 1.75.0*

### (Regressions) rust.tf/125941 *\`Vec::into\_boxed\_slice\` no\-excess guarantee regressed in 1.77.0*

### (Regressions) rust.tf/53340 *Performance regression in tight loop since rust 1.25*

### (Regressions) rust.tf/112180 *assertion failed: key as usize != KEY\_SENTVAL in DragonFly BSD*

### (Regressions) rust.tf/124216 `P-medium` *Performance regression: rustc failed to optimize \`\_mm256\_avg\_epu8\` after 1.75.0*

### (Regressions) rust.tf/125198 *regression: can't call method \`abs\` on ambiguous numeric type \`{float}\`*

### (Regressions) rust.tf/127341 `P-high` *regression: conflicting implementations of trait \`Visitable\` for type \`Box\<\_\>\`*

## Actions

- [ ] Reply to all issues/PRs discussed in this meeting, or add them to the [open action items](https://hackmd.io/Uehlc0qUQfWfvY1swYWRgQ).

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