[INFO] fetching crate ent 0.0.4...
[INFO] checking ent-0.0.4 against try#f6e2f78768c57172b99c3e85892f867894dc7e30 for pr-75502
[INFO] extracting crate ent 0.0.4 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate ent 0.0.4 on toolchain f6e2f78768c57172b99c3e85892f867894dc7e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ent 0.0.4
[INFO] finished tweaking crates.io crate ent 0.0.4
[INFO] tweaked toml for crates.io crate ent 0.0.4 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded indoc-impl v0.3.6
[INFO] [stderr]   Downloaded inventory-impl v0.1.8
[INFO] [stderr]   Downloaded inventory v0.1.8
[INFO] [stderr]   Downloaded pyo3cls v0.11.1
[INFO] [stderr]   Downloaded pyo3-derive-backend v0.11.1
[INFO] [stderr]   Downloaded pyo3 v0.11.1
[INFO] [stderr]   Downloaded unindent v0.1.6
[INFO] [stderr]   Downloaded indoc v0.3.6
[INFO] [stderr]   Downloaded ghost v0.1.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d2f3dfba637e1038eb09393d42dde23a012c9d4eabbd1b0f85a096f3f8b71ebb
[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" "d2f3dfba637e1038eb09393d42dde23a012c9d4eabbd1b0f85a096f3f8b71ebb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d2f3dfba637e1038eb09393d42dde23a012c9d4eabbd1b0f85a096f3f8b71ebb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d2f3dfba637e1038eb09393d42dde23a012c9d4eabbd1b0f85a096f3f8b71ebb", kill_on_drop: false }`
[INFO] [stdout] d2f3dfba637e1038eb09393d42dde23a012c9d4eabbd1b0f85a096f3f8b71ebb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0bb75bed93c6ca59cf478ac10f56174f9b471972eb69155b7f0813f6be6a758d
[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" "0bb75bed93c6ca59cf478ac10f56174f9b471972eb69155b7f0813f6be6a758d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking ent v0.0.4 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type or module `serde_json`
[INFO] [stdout]   --> tests/basic.rs:10:12
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let v: serde_json::Value = serde_json::from_str(r#"{"name":"test"}"#).unwrap();
[INFO] [stdout]    |            ^^^^^^^^^^ use of undeclared type or module `serde_json`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type or module `serde_json`
[INFO] [stdout]   --> tests/basic.rs:10:32
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let v: serde_json::Value = serde_json::from_str(r#"{"name":"test"}"#).unwrap();
[INFO] [stdout]    |                                ^^^^^^^^^^ use of undeclared type or module `serde_json`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0433`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ent`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "0bb75bed93c6ca59cf478ac10f56174f9b471972eb69155b7f0813f6be6a758d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0bb75bed93c6ca59cf478ac10f56174f9b471972eb69155b7f0813f6be6a758d", kill_on_drop: false }`
[INFO] [stdout] 0bb75bed93c6ca59cf478ac10f56174f9b471972eb69155b7f0813f6be6a758d