update backtrace crate

[RalfJung]

In particular this release includes rust-lang/backtrace-rs#297 and rust-lang/backtrace-rs#300.

[Mark-Simulacrum]

@bors r+

[bors]

📌 Commit 22ee27b has been approved by Mark-Simulacrum

[Centril]

Speculatively assigning blame for #69845 (comment) to this PR, @bors r-

[RalfJung]

@alexcrichton looks like a macOS-only failure in this test:

2020-03-09T07:42:04.2805000Z failures:
2020-03-09T07:42:04.2805130Z 
2020-03-09T07:42:04.2805750Z ---- [ui] ui/issues/issue-45731.rs stdout ----
2020-03-09T07:42:04.2805970Z 
2020-03-09T07:42:04.2806160Z error: test run failed!
2020-03-09T07:42:04.2806440Z status: signal: 10
2020-03-09T07:42:04.2807260Z command: "/Users/runner/runners/2.165.0/work/1/s/build/x86_64-apple-darwin/test/ui/issues/issue-45731/a"
2020-03-09T07:42:04.2807650Z stdout:
2020-03-09T07:42:04.2808250Z ------------------------------------------
2020-03-09T07:42:04.2808460Z 
2020-03-09T07:42:04.2808630Z running 1 test
2020-03-09T07:42:04.2808770Z 
2020-03-09T07:42:04.2809300Z ------------------------------------------
2020-03-09T07:42:04.2809560Z stderr:
2020-03-09T07:42:04.2810110Z ------------------------------------------
2020-03-09T07:42:04.2810310Z 
2020-03-09T07:42:04.2810840Z ------------------------------------------
2020-03-09T07:42:04.2811070Z 
2020-03-09T07:42:04.2811180Z 
2020-03-09T07:42:04.2811290Z 
2020-03-09T07:42:04.2811450Z failures:
2020-03-09T07:42:04.2811980Z     [ui] ui/issues/issue-45731.rs

This PR lands in particular rust-lang/backtrace-rs#300, which seems to do something with macOS symbol resolution. Here's the total libbacktrace diff.

"signal: 10" looks exactly like #45731 is back.

[RalfJung]

Hm, or maybe given that the fix back then was to disable mmap, maybe the issue is rust-lang/backtrace-rs#298. Cc @Aaron1011

[Aaron1011]

@RalfJung: I find it odd that the OSX tests passed for my backtrace-rs PR. There doesn't seem to be anything special about the failing test (other than the fact that it panics) as far as I can tell.

EDIT: It looks like mmap was explicitly disabled on on macOS in the past - I think we just need to add it to the build.rs in backtrace-rs.

[RalfJung]

Well, the test truncates some dSYM file. Maybe the backtrace crate does not do that.

And yes, that's what I said above -- mmap was disabled on macOS precisely because of "signal 10 SIGBUS", and your PR probably re-enabled the macOS mmap implementation.

[Aaron1011]

@RalfJung: Ooos, I didn't see the link in your previous comment.

[RalfJung]

@Aaron1011 so your proposal is to extend this check to also include macos targets?

if target.contains("windows") || target.contains("macos") {

[RalfJung]

upstream PR by @Aaron1011 already landed: rust-lang/backtrace-rs#302

[RalfJung]

@Mark-Simulacrum I bumped backtrace-sys, I think this is good to go again.

[Mark-Simulacrum]

@bors r+

[bors]

📌 Commit 9552d2e has been approved by Mark-Simulacrum

[bors]

🌲 The tree is currently closed for pull requests below priority 1000, this pull request will be tested once the tree is reopened

[Dylan-DPC-zz]

@bors p=1

[bors]

⌛ Testing commit 9552d2e with merge 38114ff...

[bors]

☀️ Test successful - checks-azure
Approved by: Mark-Simulacrum
Pushing 38114ff to master...