[INFO] fetching crate pn-sign 0.1.0...
[INFO] testing pn-sign-0.1.0 against 1.49.0 for beta-1.50-1
[INFO] extracting crate pn-sign 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate pn-sign 0.1.0 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 pn-sign 0.1.0
[INFO] finished tweaking crates.io crate pn-sign 0.1.0
[INFO] tweaked toml for crates.io crate pn-sign 0.1.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate pn-sign 0.1.0 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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 930af1ebc3c70fe8c7e1b0ff6fa4b912a6fbf6ad77ad03f0a6ef569400e1c8ef
[INFO] running `Command { std: "docker" "start" "-a" "930af1ebc3c70fe8c7e1b0ff6fa4b912a6fbf6ad77ad03f0a6ef569400e1c8ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "930af1ebc3c70fe8c7e1b0ff6fa4b912a6fbf6ad77ad03f0a6ef569400e1c8ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "930af1ebc3c70fe8c7e1b0ff6fa4b912a6fbf6ad77ad03f0a6ef569400e1c8ef", kill_on_drop: false }`
[INFO] [stdout] 930af1ebc3c70fe8c7e1b0ff6fa4b912a6fbf6ad77ad03f0a6ef569400e1c8ef
[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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 38db03a4451b8febd55589532d5691721c929aa8664fa552b26a11334d50e604
[INFO] running `Command { std: "docker" "start" "-a" "38db03a4451b8febd55589532d5691721c929aa8664fa552b26a11334d50e604", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.72
[INFO] [stderr]    Compiling proc-macro2 v1.0.18
[INFO] [stderr]    Compiling syn v1.0.34
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]    Compiling serde v1.0.114
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling byte-tools v0.3.1
[INFO] [stderr]    Compiling quick-error v1.2.3
[INFO] [stderr]    Compiling fake-simd v0.1.2
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]    Compiling opaque-debug v0.2.3
[INFO] [stderr]    Compiling termcolor v1.1.0
[INFO] [stderr]    Compiling subtle v1.0.0
[INFO] [stderr]    Compiling anyhow v1.0.31
[INFO] [stderr]    Compiling base64 v0.11.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.3
[INFO] [stderr]    Compiling proc-macro-error v1.0.3
[INFO] [stderr]    Compiling block-padding v0.1.5
[INFO] [stderr]    Compiling humantime v1.3.0
[INFO] [stderr]    Compiling headers-core v0.2.0
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling jobserver v0.1.21
[INFO] [stderr]    Compiling time v0.1.43
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling clap v2.33.1
[INFO] [stderr]    Compiling env_logger v0.7.1
[INFO] [stderr]    Compiling cc v1.0.58
[INFO] [stderr]    Compiling generic-array v0.12.3
[INFO] [stderr]    Compiling chrono v0.4.13
[INFO] [stderr]    Compiling pretty_env_logger v0.4.0
[INFO] [stderr]    Compiling digest v0.8.1
[INFO] [stderr]    Compiling block-buffer v0.7.3
[INFO] [stderr]    Compiling crypto-mac v0.7.0
[INFO] [stderr]    Compiling hmac v0.7.1
[INFO] [stderr]    Compiling sha-1 v0.8.2
[INFO] [stderr]    Compiling sha2 v0.8.2
[INFO] [stderr]    Compiling headers v0.3.2
[INFO] [stderr]    Compiling libz-sys v1.0.25
[INFO] [stderr]    Compiling libgit2-sys v0.12.7+1.0.0
[INFO] [stderr]    Compiling syn-mid v0.5.0
[INFO] [stderr]    Compiling git2 v0.13.6
[INFO] [stderr]    Compiling serde_derive v1.0.114
[INFO] [stderr]    Compiling thiserror-impl v1.0.20
[INFO] [stderr]    Compiling structopt-derive v0.4.8
[INFO] [stderr]    Compiling thiserror v1.0.20
[INFO] [stderr]    Compiling structopt v0.3.15
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling toml v0.5.6
[INFO] [stderr]    Compiling cargo-lock v4.0.1
[INFO] [stderr]    Compiling built v0.4.2
[INFO] [stderr]    Compiling pn-sign v0.1.0 (/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(backtrace)]
[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 `pn-sign`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "38db03a4451b8febd55589532d5691721c929aa8664fa552b26a11334d50e604", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "38db03a4451b8febd55589532d5691721c929aa8664fa552b26a11334d50e604", kill_on_drop: false }`
[INFO] [stdout] 38db03a4451b8febd55589532d5691721c929aa8664fa552b26a11334d50e604