[INFO] fetching crate hexponent 0.3.1...
[INFO] checking hexponent-0.3.1 against try#9c1dcf141bc0875407c4eb36972857bd3db713e2 for pr-81863
[INFO] extracting crate hexponent 0.3.1 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate hexponent 0.3.1 on toolchain 9c1dcf141bc0875407c4eb36972857bd3db713e2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate hexponent 0.3.1
[INFO] finished tweaking crates.io crate hexponent 0.3.1
[INFO] tweaked toml for crates.io crate hexponent 0.3.1 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "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-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8bdc44ae8ceeaea418388636821f837ed23be1739a12e1b710b48b17ee82ff24
[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" "8bdc44ae8ceeaea418388636821f837ed23be1739a12e1b710b48b17ee82ff24", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8bdc44ae8ceeaea418388636821f837ed23be1739a12e1b710b48b17ee82ff24", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8bdc44ae8ceeaea418388636821f837ed23be1739a12e1b710b48b17ee82ff24", kill_on_drop: false }`
[INFO] [stdout] 8bdc44ae8ceeaea418388636821f837ed23be1739a12e1b710b48b17ee82ff24
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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=forbid" "-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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "check" "--frozen" "--all" "--all-targets" "--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] 8307cae8db17ff9d532dc8ffe5f0ed315187a7a226eaec844ceb19c61e9e60cb
[INFO] running `Command { std: "docker" "start" "-a" "8307cae8db17ff9d532dc8ffe5f0ed315187a7a226eaec844ceb19c61e9e60cb", kill_on_drop: false }`
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]    Compiling serde_derive v1.0.123
[INFO] [stderr]     Checking plotters-backend v0.3.0
[INFO] [stderr]     Checking half v1.7.1
[INFO] [stderr]     Checking oorandom v11.1.3
[INFO] [stderr]     Checking hexponent v0.3.1 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]     Checking itertools v0.10.0
[INFO] [stderr]     Checking regex-automata v0.1.9
[INFO] [stderr]    Compiling cast v0.2.3
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking serde_json v1.0.62
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking serde_cbor v0.11.1
[INFO] [stderr]     Checking plotters-svg v0.3.0
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking bstr v0.2.15
[INFO] [stderr]     Checking criterion-plot v0.4.3
[INFO] [stderr]     Checking tinytemplate v1.2.0
[INFO] [stderr]     Checking csv v1.1.5
[INFO] [stderr]     Checking plotters v0.3.0
[INFO] [stderr]     Checking criterion v0.3.4
[INFO] [stdout] warning: function is never used: `f64_to_string`
[INFO] [stdout]    --> src/tests.rs:242:12
[INFO] [stdout]     |
[INFO] [stdout] 242 |     pub fn f64_to_string(f: f64) -> Result<Vec<u8>, ()> {
[INFO] [stdout]     |            ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 34.25s
[INFO] running `Command { std: "docker" "inspect" "8307cae8db17ff9d532dc8ffe5f0ed315187a7a226eaec844ceb19c61e9e60cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8307cae8db17ff9d532dc8ffe5f0ed315187a7a226eaec844ceb19c61e9e60cb", kill_on_drop: false }`
[INFO] [stdout] 8307cae8db17ff9d532dc8ffe5f0ed315187a7a226eaec844ceb19c61e9e60cb