[INFO] fetching crate holochain_metrics 0.0.52-alpha2...
[INFO] testing holochain_metrics-0.0.52-alpha2 against 1.49.0 for beta-1.50-1
[INFO] extracting crate holochain_metrics 0.0.52-alpha2 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate holochain_metrics 0.0.52-alpha2 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 holochain_metrics 0.0.52-alpha2
[INFO] finished tweaking crates.io crate holochain_metrics 0.0.52-alpha2
[INFO] tweaked toml for crates.io crate holochain_metrics 0.0.52-alpha2 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate crates.io crate holochain_metrics 0.0.52-alpha2 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-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 3b18d00a4c7441afcbc5e80fde681b12e5d93145246308ff514a3faa6f4ddd97
[INFO] running `Command { std: "docker" "start" "-a" "3b18d00a4c7441afcbc5e80fde681b12e5d93145246308ff514a3faa6f4ddd97", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3b18d00a4c7441afcbc5e80fde681b12e5d93145246308ff514a3faa6f4ddd97", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3b18d00a4c7441afcbc5e80fde681b12e5d93145246308ff514a3faa6f4ddd97", kill_on_drop: false }`
[INFO] [stdout] 3b18d00a4c7441afcbc5e80fde681b12e5d93145246308ff514a3faa6f4ddd97
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] 8916594b72c5846924902a7bcfe27f74838dac6907fc6752f33e1c90ba5f5387
[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" "8916594b72c5846924902a7bcfe27f74838dac6907fc6752f33e1c90ba5f5387", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling syn v1.0.42
[INFO] [stderr]    Compiling serde v1.0.104
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling num-traits v0.2.6
[INFO] [stderr]    Compiling regex v1.1.2
[INFO] [stderr]    Compiling protobuf v2.14.0
[INFO] [stderr]    Compiling pin-project-internal v0.4.25
[INFO] [stderr]    Compiling prometheus v0.7.0
[INFO] [stderr]    Compiling integer-encoding v1.1.5
[INFO] [stderr]    Compiling md5 v0.3.8
[INFO] [stderr]    Compiling num-derive v0.2.4
[INFO] [stderr]    Compiling snowflake v1.3.0
[INFO] [stderr]    Compiling tokio-sync v0.1.8
[INFO] [stderr]    Compiling backtrace v0.3.27
[INFO] [stderr]    Compiling tracing-core v0.1.10
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling sharded-slab v0.0.8
[INFO] [stderr]    Compiling colored v1.7.0
[INFO] [stderr]    Compiling backtrace-sys v0.1.37
[INFO] [stderr]    Compiling proc-macro2 v0.2.3
[INFO] [stderr]    Compiling idna v0.1.5
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling net2 v0.2.35
[INFO] [stderr]    Compiling time v0.1.44
[INFO] [stderr]    Compiling signal-hook-registry v1.2.1
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling dirs v1.0.5
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling hostname v0.1.5
[INFO] [stderr]    Compiling directories v1.0.2
[INFO] [stderr]    Compiling regex-automata v0.1.9
[INFO] [stderr]    Compiling rusoto_core v0.40.0
[INFO] [stderr]    Compiling aho-corasick v0.6.10
[INFO] [stderr]    Compiling csv-core v0.1.10
[INFO] [stderr]    Compiling openssl-sys v0.9.58
[INFO] [stderr]    Compiling quote v0.4.2
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling futures-cpupool v0.1.8
[INFO] [stderr]    Compiling threadpool v1.8.1
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling crossbeam-channel v0.3.8
[INFO] [stderr]    Compiling tokio-executor v0.1.10
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling holochain_common v0.0.52-alpha2
[INFO] [stderr]    Compiling crypto-mac v0.5.2
[INFO] [stderr]    Compiling url v1.7.2
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling syn v0.12.15
[INFO] [stderr]    Compiling hmac v0.5.0
[INFO] [stderr]    Compiling http v0.1.21
[INFO] [stderr]    Compiling tokio-buf v0.1.1
[INFO] [stderr]    Compiling string v0.2.1
[INFO] [stderr]    Compiling tokio-current-thread v0.1.7
[INFO] [stderr]    Compiling tokio-timer v0.2.13
[INFO] [stderr]    Compiling openssl v0.10.30
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling matchers v0.0.1
[INFO] [stderr]    Compiling quote v1.0.3
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]    Compiling ordered-float v1.1.0
[INFO] [stderr]    Compiling streaming-stats v0.2.2
[INFO] [stderr]    Compiling http-body v0.1.0
[INFO] [stderr]    Compiling shrinkwraprs v0.2.1
[INFO] [stderr]    Compiling proc-macro-error v0.2.6
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]    Compiling trackable_derive v0.1.3
[INFO] [stderr]    Compiling tracing-attributes v0.1.11
[INFO] [stderr]    Compiling shrinkwraprs v0.3.0
[INFO] [stderr]    Compiling structopt-derive v0.3.3
[INFO] [stderr]    Compiling trackable v0.2.23
[INFO] [stderr]    Compiling rustracing v0.2.1
[INFO] [stderr]    Compiling thrift_codec v0.1.1
[INFO] [stderr]    Compiling tracing v0.1.13
[INFO] [stderr]    Compiling structopt v0.3.3
[INFO] [stderr]    Compiling rustracing_jaeger v0.2.1
[INFO] [stderr]    Compiling pin-project v0.4.25
[INFO] [stderr]    Compiling chrono v0.4.6
[INFO] [stderr]    Compiling serde_json v1.0.47
[INFO] [stderr]    Compiling bincode v1.3.1
[INFO] [stderr]    Compiling tracing-serde v0.1.1
[INFO] [stderr]    Compiling serde_urlencoded v0.5.5
[INFO] [stderr]    Compiling bstr v0.2.13
[INFO] [stderr]    Compiling toml v0.5.0
[INFO] [stderr]    Compiling tokio-io v0.1.13
[INFO] [stderr]    Compiling mio v0.6.22
[INFO] [stderr]    Compiling tokio-threadpool v0.1.18
[INFO] [stderr]    Compiling want v0.2.0
[INFO] [stderr]    Compiling native-tls v0.2.4
[INFO] [stderr]    Compiling thrift v0.13.0
[INFO] [stderr]    Compiling tracing-log v0.1.1
[INFO] [stderr]    Compiling env_logger v0.6.1
[INFO] [stderr]    Compiling opentelemetry v0.2.0
[INFO] [stderr]    Compiling tokio-codec v0.1.2
[INFO] [stderr]    Compiling h2 v0.1.26
[INFO] [stderr]    Compiling csv v1.1.3
[INFO] [stderr]    Compiling tokio-reactor v0.1.12
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling tracing-subscriber v0.2.3
[INFO] [stderr]    Compiling holochain_locksmith v0.0.52-alpha2
[INFO] [stderr]    Compiling holochain_logging v0.0.7
[INFO] [stderr]    Compiling tokio-fs v0.1.7
[INFO] [stderr]    Compiling tokio-udp v0.1.6
[INFO] [stderr]    Compiling tokio-uds v0.2.7
[INFO] [stderr]    Compiling tokio-tcp v0.1.4
[INFO] [stderr]    Compiling tokio-signal v0.2.9
[INFO] [stderr]    Compiling opentelemetry-jaeger v0.1.0
[INFO] [stderr]    Compiling tokio-process v0.2.5
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling holochain_tracing v0.0.24
[INFO] [stderr]    Compiling hyper v0.12.35
[INFO] [stderr]    Compiling holochain_tracing_macros v0.0.24
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/holochain_tracing_macros-0.0.24/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(proc_macro_span)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `holochain_tracing_macros`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "8916594b72c5846924902a7bcfe27f74838dac6907fc6752f33e1c90ba5f5387", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8916594b72c5846924902a7bcfe27f74838dac6907fc6752f33e1c90ba5f5387", kill_on_drop: false }`
[INFO] [stdout] 8916594b72c5846924902a7bcfe27f74838dac6907fc6752f33e1c90ba5f5387