[INFO] cloning repository https://github.com/undefinedvalue/asynctest
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/undefinedvalue/asynctest" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fundefinedvalue%2Fasynctest", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fundefinedvalue%2Fasynctest'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c7849111ba8aaa2e39208d8b335ac507479b10bc
[INFO] testing undefinedvalue/asynctest against beta-2026-04-21 for beta-1.96-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fundefinedvalue%2Fasynctest" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] removed /workspace/builds/worker-5-tc2/source/rust-toolchain.toml
[INFO] started tweaking git repo https://github.com/undefinedvalue/asynctest
[INFO] finished tweaking git repo https://github.com/undefinedvalue/asynctest
[INFO] tweaked toml for git repo https://github.com/undefinedvalue/asynctest written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/undefinedvalue/asynctest on toolchain beta-2026-04-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/undefinedvalue/asynctest already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr]   |
[INFO] [stderr]   = note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr]   = note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr]   = note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] dd1202e6f3c6c40e8a8d0dd4c06eb015ceecdf9c3886c37e505af503819f202b
[INFO] running `Command { std: "docker" "start" "-a" "dd1202e6f3c6c40e8a8d0dd4c06eb015ceecdf9c3886c37e505af503819f202b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dd1202e6f3c6c40e8a8d0dd4c06eb015ceecdf9c3886c37e505af503819f202b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dd1202e6f3c6c40e8a8d0dd4c06eb015ceecdf9c3886c37e505af503819f202b", kill_on_drop: false }`
[INFO] [stdout] dd1202e6f3c6c40e8a8d0dd4c06eb015ceecdf9c3886c37e505af503819f202b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 79c6e6b8dfd588e8a568c4a45774f04a3878639ebe52b6d5c341482ba652b792
[INFO] running `Command { std: "docker" "start" "-a" "79c6e6b8dfd588e8a568c4a45774f04a3878639ebe52b6d5c341482ba652b792", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr]   |
[INFO] [stderr]   = note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr]   = note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr]   = note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] [stderr]    Compiling asynclib v0.0.0 (/opt/rustwide/workdir/asynclib)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> asynclib/src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(async_fn_in_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `async_fn_in_trait` has been stable since `1.75.0` and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `async_fn_in_trait` has been stable since 1.75.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> asynclib/src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(async_fn_in_trait)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `asynclib` (lib) due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "79c6e6b8dfd588e8a568c4a45774f04a3878639ebe52b6d5c341482ba652b792", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79c6e6b8dfd588e8a568c4a45774f04a3878639ebe52b6d5c341482ba652b792", kill_on_drop: false }`
[INFO] [stdout] 79c6e6b8dfd588e8a568c4a45774f04a3878639ebe52b6d5c341482ba652b792