[INFO] cloning repository https://github.com/denoland/serde_v8
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/denoland/serde_v8" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdenoland%2Fserde_v8", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdenoland%2Fserde_v8'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 739242ee9406eb22bc942e08ba344cfbf949c8db
[INFO] checking denoland/serde_v8 against try#4c35efa5bf9c956a3bd39021cc9699d125584977 for pr-104746
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdenoland%2Fserde_v8" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/denoland/serde_v8 on toolchain 4c35efa5bf9c956a3bd39021cc9699d125584977
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4c35efa5bf9c956a3bd39021cc9699d125584977" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/denoland/serde_v8
[INFO] removed 0 missing examples
[INFO] finished tweaking git repo https://github.com/denoland/serde_v8
[INFO] tweaked toml for git repo https://github.com/denoland/serde_v8 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/denoland/serde_v8 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4c35efa5bf9c956a3bd39021cc9699d125584977" "fetch" "--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-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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:bb5b0feb4f87116a4ea905b7ff5bf5b85913db05e9f0fbc1abdd3168928d9075" "/opt/rustwide/cargo-home/bin/cargo" "+4c35efa5bf9c956a3bd39021cc9699d125584977" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5a2da51146df4a11bc7583469a69b459f348d59a13274571716bbe33dc22a110
[INFO] running `Command { std: "docker" "start" "-a" "5a2da51146df4a11bc7583469a69b459f348d59a13274571716bbe33dc22a110", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5a2da51146df4a11bc7583469a69b459f348d59a13274571716bbe33dc22a110", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5a2da51146df4a11bc7583469a69b459f348d59a13274571716bbe33dc22a110", kill_on_drop: false }`
[INFO] [stdout] 5a2da51146df4a11bc7583469a69b459f348d59a13274571716bbe33dc22a110
[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=forbid" "-e" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:bb5b0feb4f87116a4ea905b7ff5bf5b85913db05e9f0fbc1abdd3168928d9075" "/opt/rustwide/cargo-home/bin/cargo" "+4c35efa5bf9c956a3bd39021cc9699d125584977" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 045217b82db73876cfe85e7bc9bf98bf15d0e87e035a05e6936d7bc81487750f
[INFO] running `Command { std: "docker" "start" "-a" "045217b82db73876cfe85e7bc9bf98bf15d0e87e035a05e6936d7bc81487750f", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.96
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]     Checking bencher v0.1.5
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling fslock v0.1.6
[INFO] [stderr]    Compiling which v4.1.0
[INFO] [stderr]    Compiling rusty_v8 v0.32.0
[INFO] [stderr]     Checking serde_v8 v0.15.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: fields `a`, `b`, and `operator` are never read
[INFO] [stdout]   --> examples/basic.rs:8:7
[INFO] [stdout]    |
[INFO] [stdout] 7  | struct MathOp {
[INFO] [stdout]    |        ------ fields in this struct
[INFO] [stdout] 8  |   pub a: u64,
[INFO] [stdout]    |       ^
[INFO] [stdout] 9  |   pub b: u64,
[INFO] [stdout]    |       ^
[INFO] [stdout] 10 |   pub operator: Option<String>,
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `MathOp` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[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 16.22s
[INFO] running `Command { std: "docker" "inspect" "045217b82db73876cfe85e7bc9bf98bf15d0e87e035a05e6936d7bc81487750f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "045217b82db73876cfe85e7bc9bf98bf15d0e87e035a05e6936d7bc81487750f", kill_on_drop: false }`
[INFO] [stdout] 045217b82db73876cfe85e7bc9bf98bf15d0e87e035a05e6936d7bc81487750f