Make usdt an optional default feature

[konstin]

This fixes cross-compilation. I've verified this with the command below.

SDKROOT=${SDK_ROOT}/macos-sdk \
    CFLAGS_aarch64_apple_darwin="-isystem ${SDK_ROOT}/macos-sdk/usr/include" \
    RUSTFLAGS="-C link-arg=-F${SDK_ROOT}/macos-sdk/System/Library/Frameworks -C link-arg=-L${SDK_ROOT}/macos-sdk/usr/lib" \
    cargo zigbuild --target aarch64-apple-darwin --no-default-features --features default-no-update,self-update

Fixes #3026

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.02%. Comparing base (362c6ae) to head (572d7fb).
⚠️ Report is 16 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3027      +/-   ##
==========================================
- Coverage   83.10%   83.02%   -0.09%     
==========================================
  Files         154      155       +1     
  Lines       40919    42251    +1332     
==========================================
+ Hits        34004    35077    +1073     
- Misses       6915     7174     +259     

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[sunshowers]

Thanks. Trying to understand this in more detail:

Based on oxidecomputer/usdt@master...konstin:usdt:master I guess this is an issue when cross-compiling to another architecture (not just another OS). Now our release builds perform cross-compiles from:

1. x86_64 Linux to aarch64 Linux
2. x86_64 Linux to x86_64 FreeBSD
3. x86_64 Linux to x86_64 illumos
4. aarch64 macOS to x86_64 macOS

1 isn't an issue because the usdt crate already doesn't work on aarch64 Linux.

2 and 3 aren't issues because we're compiling to the same architecture.

4 isn't an issue because the usdt crate doesn't work on x86_64 macOS.

But based on the command line you pasted, what you're trying to do is compile from x86_64 macOS to aarch64 macOS. So you run into this USDT issue.

Is my understanding correct?

[sunshowers]

usdt should be moved to default-no-update below.

[konstin]

That naming went straight over my head, updated.

[konstin]

For posterity, to run the build command, you now need to be in ./cargo-nextest, not in root, as the root unconditionally activates default-no-updat. (This works when fetching the .crate file for cargo-nextest from crates.io, which I did before patching).

cargo-nextest = { path = "cargo-nextest", default-features = false, features = [
    "default-no-update",
] }

SDKROOT=${SDK_ROOT}/macos-sdk     CFLAGS_aarch64_apple_darwin="-isystem ${SDK_ROOT}/macos-sdk/usr/include"     RUSTFLAGS="-C link-arg=-F${SDK_ROOT}/macos-sdk/System/Library/Frameworks -C link-arg=-L${SDK_ROOT}/macos-sdk/usr/lib"     cargo zigbuild --target aarch64-apple-darwin --no-default-features

[sunshowers]

Yeah. I would expect the following to work:

• cargo install --locked cargo-nextest --no-default-features --features default-no-update
• cargo build -p cargo-nextest --no-default-features --features default-no-update
• cargo install --locked --git https://github.com/nextest-rs/nextest --no-default-features --features default-no-update

[konstin]

I was trying to build packages for {linux, windows, mac} x {x86_64, aarch64} from a linux x86_64 host in a docker container (though a linux aarch64 host would also work, x86_64 is just more conveniently available for me).

[sunshowers]

Thanks!