[INFO] fetching crate buildkit-frontend 0.3.0...
[INFO] testing buildkit-frontend-0.3.0 against 1.49.0 for beta-1.50-1
[INFO] extracting crate buildkit-frontend 0.3.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate buildkit-frontend 0.3.0 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 buildkit-frontend 0.3.0
[INFO] finished tweaking crates.io crate buildkit-frontend 0.3.0
[INFO] tweaked toml for crates.io crate buildkit-frontend 0.3.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate buildkit-frontend 0.3.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 232cfe6356b559417a600cc176bd0f1ff854b9963a2753088490b0f64d7c5ea2
[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" "232cfe6356b559417a600cc176bd0f1ff854b9963a2753088490b0f64d7c5ea2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "232cfe6356b559417a600cc176bd0f1ff854b9963a2753088490b0f64d7c5ea2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "232cfe6356b559417a600cc176bd0f1ff854b9963a2753088490b0f64d7c5ea2", kill_on_drop: false }`
[INFO] [stdout] 232cfe6356b559417a600cc176bd0f1ff854b9963a2753088490b0f64d7c5ea2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] fa3da81ec45838405691d78448f3a11dcdf4f77777f9b0842c8a65fa64c2edeb
[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" "fa3da81ec45838405691d78448f3a11dcdf4f77777f9b0842c8a65fa64c2edeb", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.16
[INFO] [stderr]    Compiling libc v0.2.67
[INFO] [stderr]    Compiling tower-layer v0.3.0
[INFO] [stderr]    Compiling typenum v1.11.2
[INFO] [stderr]    Compiling multimap v0.8.0
[INFO] [stderr]    Compiling regex-syntax v0.6.16
[INFO] [stderr]    Compiling futures-channel v0.3.4
[INFO] [stderr]    Compiling tracing-core v0.1.10
[INFO] [stderr]    Compiling backtrace-sys v0.1.33
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling aho-corasick v0.7.9
[INFO] [stderr]    Compiling net2 v0.2.33
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling num_cpus v1.12.0
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling which v3.1.0
[INFO] [stderr]    Compiling time v0.1.42
[INFO] [stderr]    Compiling backtrace v0.3.45
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling generic-array v0.12.3
[INFO] [stderr]    Compiling prost-build v0.6.1
[INFO] [stderr]    Compiling mio v0.6.21
[INFO] [stderr]    Compiling rand_chacha v0.2.1
[INFO] [stderr]    Compiling rand_pcg v0.2.1
[INFO] [stderr]    Compiling digest v0.8.1
[INFO] [stderr]    Compiling block-buffer v0.7.3
[INFO] [stderr]    Compiling sha2 v0.8.1
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling regex v1.3.4
[INFO] [stderr]    Compiling tempfile v3.1.0
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]    Compiling pin-project-internal v0.4.8
[INFO] [stderr]    Compiling proc-macro-hack v0.5.11
[INFO] [stderr]    Compiling prost-derive v0.6.1
[INFO] [stderr]    Compiling tracing-attributes v0.1.7
[INFO] [stderr]    Compiling async-stream-impl v0.2.1
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]    Compiling async-trait v0.1.24
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling tokio v0.2.13
[INFO] [stderr]    Compiling async-stream v0.2.1
[INFO] [stderr]    Compiling failure v0.1.6
[INFO] [stderr]    Compiling futures-macro v0.3.4
[INFO] [stderr]    Compiling tracing v0.1.13
[INFO] [stderr]    Compiling pin-project v0.4.8
[INFO] [stderr]    Compiling tower-discover v0.3.0
[INFO] [stderr]    Compiling tower-load-shed v0.3.0
[INFO] [stderr]    Compiling tracing-futures v0.2.3
[INFO] [stderr]    Compiling futures-util v0.3.4
[INFO] [stderr]    Compiling prost v0.6.1
[INFO] [stderr]    Compiling prost-types v0.6.1
[INFO] [stderr]    Compiling tokio-util v0.2.0
[INFO] [stderr]    Compiling tower-retry v0.3.0
[INFO] [stderr]    Compiling tower-timeout v0.3.0
[INFO] [stderr]    Compiling tower-load v0.3.0
[INFO] [stderr]    Compiling tower-buffer v0.3.0
[INFO] [stderr]    Compiling tower-make v0.3.0
[INFO] [stderr]    Compiling tower-limit v0.3.0
[INFO] [stderr]    Compiling h2 v0.2.2
[INFO] [stderr]    Compiling tower-ready-cache v0.3.1
[INFO] [stderr]    Compiling tower-util v0.3.0
[INFO] [stderr]    Compiling futures-executor v0.3.4
[INFO] [stderr]    Compiling serde v1.0.104
[INFO] [stderr]    Compiling tower-balance v0.3.0
[INFO] [stderr]    Compiling futures v0.3.4
[INFO] [stderr]    Compiling tower v0.3.1
[INFO] [stderr]    Compiling tonic-build v0.1.1
[INFO] [stderr]    Compiling buildkit-proto v0.2.0
[INFO] [stderr]    Compiling hyper v0.13.3
[INFO] [stderr]    Compiling serde_json v1.0.48
[INFO] [stderr]    Compiling chrono v0.4.10
[INFO] [stderr]    Compiling tonic v0.1.1
[INFO] [stderr]    Compiling buildkit-llb v0.2.0
[INFO] [stderr]    Compiling buildkit-frontend v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3m 00s
[INFO] running `Command { std: "docker" "inspect" "fa3da81ec45838405691d78448f3a11dcdf4f77777f9b0842c8a65fa64c2edeb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fa3da81ec45838405691d78448f3a11dcdf4f77777f9b0842c8a65fa64c2edeb", kill_on_drop: false }`
[INFO] [stdout] fa3da81ec45838405691d78448f3a11dcdf4f77777f9b0842c8a65fa64c2edeb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7c93ab68175a939cacbc283c4ff5436eefda6d7ff5cba724759753ca3bc3f4c2
[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" "7c93ab68175a939cacbc283c4ff5436eefda6d7ff5cba724759753ca3bc3f4c2", kill_on_drop: false }`
[INFO] [stderr]    Compiling pretty_assertions v0.6.1
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling env_logger v0.6.2
[INFO] [stderr]    Compiling buildkit-frontend v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr] error: could not compile `buildkit-frontend`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustc --crate-name download --edition=2018 examples/download.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 -C metadata=71c407cfe580ef53 -C extra-filename=-71c407cfe580ef53 --out-dir /opt/rustwide/target/debug/examples -L dependency=/opt/rustwide/target/debug/deps --extern async_trait=/opt/rustwide/target/debug/deps/libasync_trait-f30b29d303b37f68.so --extern buildkit_frontend=/opt/rustwide/target/debug/deps/libbuildkit_frontend-1bcc89d790b7ca39.rlib --extern buildkit_llb=/opt/rustwide/target/debug/deps/libbuildkit_llb-133303fb5bed8e61.rlib --extern buildkit_proto=/opt/rustwide/target/debug/deps/libbuildkit_proto-729a4a7206675cbe.rlib --extern bytes=/opt/rustwide/target/debug/deps/libbytes-c2d6a084219fa12b.rlib --extern chrono=/opt/rustwide/target/debug/deps/libchrono-6c8bc8792e24561b.rlib --extern either=/opt/rustwide/target/debug/deps/libeither-3ae76b7b3289f774.rlib --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-1392576dbecd63dc.rlib --extern failure=/opt/rustwide/target/debug/deps/libfailure-8854e8e7ed5d56d4.rlib --extern futures=/opt/rustwide/target/debug/deps/libfutures-a676c93c51282834.rlib --extern libc=/opt/rustwide/target/debug/deps/liblibc-d7093660885ad222.rlib --extern log=/opt/rustwide/target/debug/deps/liblog-1761913616bdc5f1.rlib --extern mio=/opt/rustwide/target/debug/deps/libmio-75a49797a264c2cf.rlib --extern pin_project=/opt/rustwide/target/debug/deps/libpin_project-1845ecfde7decc3c.rlib --extern pretty_assertions=/opt/rustwide/target/debug/deps/libpretty_assertions-5f40f5019e43dab8.rlib --extern regex=/opt/rustwide/target/debug/deps/libregex-c434f103c792b755.rlib --extern serde=/opt/rustwide/target/debug/deps/libserde-20fc5ca8f845c706.rlib --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-65f6bb928130689d.rlib --extern tokio=/opt/rustwide/target/debug/deps/libtokio-5d6a8603185f2d55.rlib --extern tonic=/opt/rustwide/target/debug/deps/libtonic-56fb3f024493e596.rlib --extern tower=/opt/rustwide/target/debug/deps/libtower-07c301b98705a0f2.rlib --extern url=/opt/rustwide/target/debug/deps/liburl-c2e96d08d138ae4f.rlib --cap-lints=warn -L native=/opt/rustwide/target/debug/build/backtrace-sys-4b5f9fdb2eab0e64/out` (signal: 9, SIGKILL: kill)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "7c93ab68175a939cacbc283c4ff5436eefda6d7ff5cba724759753ca3bc3f4c2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7c93ab68175a939cacbc283c4ff5436eefda6d7ff5cba724759753ca3bc3f4c2", kill_on_drop: false }`
[INFO] [stdout] 7c93ab68175a939cacbc283c4ff5436eefda6d7ff5cba724759753ca3bc3f4c2