[INFO] fetching crate fake_serialize 0.1.1...
[INFO] checking fake_serialize-0.1.1 against master#90442458ac46b1d5eed752c316da25450f67285b for pr-81477
[INFO] extracting crate fake_serialize 0.1.1 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate fake_serialize 0.1.1 on toolchain 90442458ac46b1d5eed752c316da25450f67285b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate fake_serialize 0.1.1
[INFO] finished tweaking crates.io crate fake_serialize 0.1.1
[INFO] tweaked toml for crates.io crate fake_serialize 0.1.1 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate crates.io crate fake_serialize 0.1.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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:ea7d7bff36b2ba8ce4de8bba1d2dea90376bc481f1a945a913994a8c492e40c1" "/opt/rustwide/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 96560f9b61053e22860ca7509928422bc793dc9d499f8cf2501c51b989b70944
[INFO] running `Command { std: "docker" "start" "-a" "96560f9b61053e22860ca7509928422bc793dc9d499f8cf2501c51b989b70944", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "96560f9b61053e22860ca7509928422bc793dc9d499f8cf2501c51b989b70944", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "96560f9b61053e22860ca7509928422bc793dc9d499f8cf2501c51b989b70944", kill_on_drop: false }`
[INFO] [stdout] 96560f9b61053e22860ca7509928422bc793dc9d499f8cf2501c51b989b70944
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:ea7d7bff36b2ba8ce4de8bba1d2dea90376bc481f1a945a913994a8c492e40c1" "/opt/rustwide/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cd3b9a92840af7660d27ac08c62acf005481a9a98f3756bba6935e1a114da1c4
[INFO] running `Command { std: "docker" "start" "-a" "cd3b9a92840af7660d27ac08c62acf005481a9a98f3756bba6935e1a114da1c4", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.7
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling serde v1.0.104
[INFO] [stderr]     Checking quote v1.0.2
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]     Checking fake_serialize v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serde_json`
[INFO] [stdout]   --> examples/constraint.rs:21:20
[INFO] [stdout]    |
[INFO] [stdout] 21 |         let json = serde_json::to_string(t).unwrap();
[INFO] [stdout]    |                    ^^^^^^^^^^ use of undeclared crate or module `serde_json`
[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 E0433`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `fake_serialize`
[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" "cd3b9a92840af7660d27ac08c62acf005481a9a98f3756bba6935e1a114da1c4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cd3b9a92840af7660d27ac08c62acf005481a9a98f3756bba6935e1a114da1c4", kill_on_drop: false }`
[INFO] [stdout] cd3b9a92840af7660d27ac08c62acf005481a9a98f3756bba6935e1a114da1c4