[INFO] fetching crate jvm-serializable 0.0.2...
[INFO] testing jvm-serializable-0.0.2 against 1.49.0 for beta-1.50-1
[INFO] extracting crate jvm-serializable 0.0.2 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate jvm-serializable 0.0.2 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate jvm-serializable 0.0.2
[INFO] finished tweaking crates.io crate jvm-serializable 0.0.2
[INFO] tweaked toml for crates.io crate jvm-serializable 0.0.2 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6f41903fe2c07e1c317b0d2efd5b2bd757979cbcbbba9ca148fba2c8c56c8491
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "6f41903fe2c07e1c317b0d2efd5b2bd757979cbcbbba9ca148fba2c8c56c8491", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6f41903fe2c07e1c317b0d2efd5b2bd757979cbcbbba9ca148fba2c8c56c8491", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6f41903fe2c07e1c317b0d2efd5b2bd757979cbcbbba9ca148fba2c8c56c8491", kill_on_drop: false }`
[INFO] [stdout] 6f41903fe2c07e1c317b0d2efd5b2bd757979cbcbbba9ca148fba2c8c56c8491
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] dc0089af0f54f0c7d39c248fee4d3b0e7ef5ee9834491ea245e33e43a8936890
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "dc0089af0f54f0c7d39c248fee4d3b0e7ef5ee9834491ea245e33e43a8936890", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde_derive_internals v0.25.0
[INFO] [stderr]    Compiling bincode v1.3.1
[INFO] [stderr]    Compiling jvm-macro v0.0.1
[INFO] [stderr]    Compiling jvm-serializable v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(type_name_of_val)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(core_intrinsics)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(get_mut_unchecked)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]  --> src/lib.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #[macro_use]
[INFO] [stdout]   | ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]  --> src/lib.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #[macro_use]
[INFO] [stdout]   | ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc`, `Mutex`
[INFO] [stdout]   --> src/lib.rs:19:25
[INFO] [stdout]    |
[INFO] [stdout] 19 |         use std::sync::{Mutex, Arc};
[INFO] [stdout]    |                         ^^^^^  ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::time::Instant`
[INFO] [stdout]   --> src/lib.rs:21:13
[INFO] [stdout]    |
[INFO] [stdout] 21 |         use std::time::Instant;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Formatter`, `TryFrom`
[INFO] [stdout]   --> src/lib.rs:23:29
[INFO] [stdout]    |
[INFO] [stdout] 23 |         use serde::export::{Formatter, TryFrom};
[INFO] [stdout]    |                             ^^^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `AtomicBool`, `Ordering`
[INFO] [stdout]   --> src/lib.rs:25:33
[INFO] [stdout]    |
[INFO] [stdout] 25 |         use std::sync::atomic::{AtomicBool, Ordering};
[INFO] [stdout]    |                                 ^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors; 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `jvm-serializable`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "dc0089af0f54f0c7d39c248fee4d3b0e7ef5ee9834491ea245e33e43a8936890", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dc0089af0f54f0c7d39c248fee4d3b0e7ef5ee9834491ea245e33e43a8936890", kill_on_drop: false }`
[INFO] [stdout] dc0089af0f54f0c7d39c248fee4d3b0e7ef5ee9834491ea245e33e43a8936890