[INFO] fetching crate chunk-json-lite 0.1.0...
[INFO] checking chunk-json-lite-0.1.0 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] extracting crate chunk-json-lite 0.1.0 into /workspace/builds/worker-2-tc1/source
[INFO] validating manifest of crates.io crate chunk-json-lite 0.1.0 on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate chunk-json-lite 0.1.0
[INFO] finished tweaking crates.io crate chunk-json-lite 0.1.0
[INFO] tweaked toml for crates.io crate chunk-json-lite 0.1.0 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate crates.io crate chunk-json-lite 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded count-write v0.1.0
[INFO] [stderr]   Downloaded main_error v0.1.0
[INFO] [stderr]   Downloaded json v0.12.0
[INFO] [stderr]   Downloaded human-size v0.4.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ccbcce700ac036483ac4b6f4ace3d30adec48cc231c426f36771d76c3b1ca75c
[INFO] running `Command { std: "docker" "start" "-a" "ccbcce700ac036483ac4b6f4ace3d30adec48cc231c426f36771d76c3b1ca75c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ccbcce700ac036483ac4b6f4ace3d30adec48cc231c426f36771d76c3b1ca75c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ccbcce700ac036483ac4b6f4ace3d30adec48cc231c426f36771d76c3b1ca75c", kill_on_drop: false }`
[INFO] [stdout] ccbcce700ac036483ac4b6f4ace3d30adec48cc231c426f36771d76c3b1ca75c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ea26331c4784c5f4ad27a0b7994c5fa198094c28d2e16b3bf7bfdf780812275f
[INFO] running `Command { std: "docker" "start" "-a" "ea26331c4784c5f4ad27a0b7994c5fa198094c28d2e16b3bf7bfdf780812275f", kill_on_drop: false }`
[INFO] [stderr]     Checking main_error v0.1.0
[INFO] [stderr]     Checking human-size v0.4.0
[INFO] [stderr]     Checking json v0.12.0
[INFO] [stderr]     Checking count-write v0.1.0
[INFO] [stderr]     Checking chunk-json-lite v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/main.rs:49:13
[INFO] [stdout]    |
[INFO] [stdout] 49 |             mem::replace(&mut writer, new);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 49 |             let _ = mem::replace(&mut writer, new);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/main.rs:49:13
[INFO] [stdout]    |
[INFO] [stdout] 49 |             mem::replace(&mut writer, new);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 49 |             let _ = mem::replace(&mut writer, new);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.01s
[INFO] running `Command { std: "docker" "inspect" "ea26331c4784c5f4ad27a0b7994c5fa198094c28d2e16b3bf7bfdf780812275f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ea26331c4784c5f4ad27a0b7994c5fa198094c28d2e16b3bf7bfdf780812275f", kill_on_drop: false }`
[INFO] [stdout] ea26331c4784c5f4ad27a0b7994c5fa198094c28d2e16b3bf7bfdf780812275f