[INFO] fetching crate mango-test 0.2.1...
[INFO] testing mango-test-0.2.1 against 1.90.0 for beta-1.91-3
[INFO] extracting crate mango-test 0.2.1 into /workspace/builds/worker-1-tc1/source
[INFO] started tweaking crates.io crate mango-test 0.2.1
[INFO] finished tweaking crates.io crate mango-test 0.2.1
[INFO] tweaked toml for crates.io crate mango-test 0.2.1 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate mango-test 0.2.1 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 7 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded mango-core v0.2.1
[INFO] [stderr]   Downloaded qemu-exit v3.0.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a5c4071f62d2800708a7d1622fd49d8a6bccbfbe4af9d933e82c10fec374e88f
[INFO] running `Command { std: "docker" "start" "-a" "a5c4071f62d2800708a7d1622fd49d8a6bccbfbe4af9d933e82c10fec374e88f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a5c4071f62d2800708a7d1622fd49d8a6bccbfbe4af9d933e82c10fec374e88f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a5c4071f62d2800708a7d1622fd49d8a6bccbfbe4af9d933e82c10fec374e88f", kill_on_drop: false }`
[INFO] [stdout] a5c4071f62d2800708a7d1622fd49d8a6bccbfbe4af9d933e82c10fec374e88f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 391fc45f5a98e69817cbc409a0895f4cd04aa91b365c21505c7262dea6133cb9
[INFO] running `Command { std: "docker" "start" "-a" "391fc45f5a98e69817cbc409a0895f4cd04aa91b365c21505c7262dea6133cb9", kill_on_drop: false }`
[INFO] [stderr]    Compiling spin v0.9.8
[INFO] [stderr]    Compiling lazy_static v1.5.0
[INFO] [stderr]    Compiling mango-core v0.2.1
[INFO] [stderr]    Compiling mango-test v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(custom_test_frameworks)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mango-test` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "391fc45f5a98e69817cbc409a0895f4cd04aa91b365c21505c7262dea6133cb9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "391fc45f5a98e69817cbc409a0895f4cd04aa91b365c21505c7262dea6133cb9", kill_on_drop: false }`
[INFO] [stdout] 391fc45f5a98e69817cbc409a0895f4cd04aa91b365c21505c7262dea6133cb9
