MSRV regression on Windows

[camshaft]

We run rustc 1.71.1 in our CI and noticed that the Windows builds started failing yesterday: https://github.com/aws/s2n-quic/actions/runs/8394213178/job/22990857677?pr=2159#step:8:390.

The newest release seems to be using ptr::from_ref, which was not stabilized until 1.76.0. However, the documented MSRV in the backtrace crate is 1.65.0:

backtrace-rs/Cargo.toml

Line 18 in 6fa4b85

rust-version = "1.65.0"

Either we should use something that is compatible with 1.65 or the MSRV needs to be bumped.

I also noticed that the CI does not test against your advertised MSRV:

backtrace-rs/.github/workflows/main.yml

Lines 19 to 36 in 6fa4b85

	- os: ubuntu-20.04
	rust: stable
	- os: ubuntu-20.04
	rust: beta
	- os: ubuntu-20.04
	rust: nightly
	- os: macos-latest
	rust: stable
	- os: macos-latest
	rust: nightly
	# Note that these are on nightly due to rust-lang/rust#63700 not being
	# on stable yet
	- os: windows-latest
	rust: stable-x86_64-msvc
	- os: windows-latest
	rust: stable-i686-msvc
	- os: windows-latest
	rust: stable-x86_64-gnu

This should also be addressed :).

[ChrisDenton]

See https://github.com/rust-lang/backtrace-rs?tab=readme-ov-file#supported-rust-versions

By that policy the current MSRV is actually 1.75 (or maybe 1.74 since the latest release is still new), it just hasn't been updated elsewhere yet. MSRV is tested but currently only for Linux:

backtrace-rs/.github/workflows/main.yml

Lines 235 to 244 in 6fa4b85

	msrv:
	name: MSRV
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v3
	with:
	submodules: true
	- name: Install Rust
	run: rustup update 1.65.0 && rustup default 1.65.0
	- run: cargo build

[workingjubilee]

Ah, my apologies. Yes, we need to run the MSRV tests on Windows too, I suppose, but yes, any replacement is allowed to be one that breaks your CI anyways.

[camshaft]

By that policy the current MSRV is actually 1.75 (or maybe 1.74 since the latest release is still new), it just hasn't been updated elsewhere yet.

I guess that's fine. It just makes it more difficult to debug when consuming without having the rust-version updated in Cargo.toml.

[workingjubilee]

I'll try to get a 0.3.71 out the door, it looks like ptr::from_ref was the only breaking thing there, and get 0.3.70 yanked, after #598

[workingjubilee]

0.3.71 is published and 0.3.70 is yanked!

[camshaft]

Thanks!