[INFO] fetching crate chainmap 0.1.2...
[INFO] checking chainmap-0.1.2 against master#0f6e1ae67854c3c44726e8376144c16b465fe7c6 for pr-129392
[INFO] extracting crate chainmap 0.1.2 into /workspace/builds/worker-0-tc1/source
[INFO] validating manifest of crates.io crate chainmap 0.1.2 on toolchain 0f6e1ae67854c3c44726e8376144c16b465fe7c6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0f6e1ae67854c3c44726e8376144c16b465fe7c6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate chainmap 0.1.2
[INFO] finished tweaking crates.io crate chainmap 0.1.2
[INFO] tweaked toml for crates.io crate chainmap 0.1.2 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0f6e1ae67854c3c44726e8376144c16b465fe7c6" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0f6e1ae67854c3c44726e8376144c16b465fe7c6" "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-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "+0f6e1ae67854c3c44726e8376144c16b465fe7c6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2126652f953d799b9535f04069c08bad1078fc1156947d1e86aa5ae2193fccab
[INFO] running `Command { std: "docker" "start" "-a" "2126652f953d799b9535f04069c08bad1078fc1156947d1e86aa5ae2193fccab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2126652f953d799b9535f04069c08bad1078fc1156947d1e86aa5ae2193fccab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2126652f953d799b9535f04069c08bad1078fc1156947d1e86aa5ae2193fccab", kill_on_drop: false }`
[INFO] [stdout] 2126652f953d799b9535f04069c08bad1078fc1156947d1e86aa5ae2193fccab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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" "+0f6e1ae67854c3c44726e8376144c16b465fe7c6" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 89751b5f13afc6b454c17867a8612fb222ff71e3a323e564e3a4e9bc7ac70bd3
[INFO] running `Command { std: "docker" "start" "-a" "89751b5f13afc6b454c17867a8612fb222ff71e3a323e564e3a4e9bc7ac70bd3", kill_on_drop: false }`
[INFO] [stderr]     Checking chainmap v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/lib.rs:331:9
[INFO] [stdout]     |
[INFO] [stdout] 331 |         std::mem::replace(&mut *self, oldlevel);
[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] 331 |         let _ = std::mem::replace(&mut *self, oldlevel);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/lib.rs:416:9
[INFO] [stdout]     |
[INFO] [stdout] 416 |         std::mem::replace(&mut *self, oldlevel);
[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] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 416 |         let _ = std::mem::replace(&mut *self, oldlevel);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/lib.rs:331:9
[INFO] [stdout]     |
[INFO] [stdout] 331 |         std::mem::replace(&mut *self, oldlevel);
[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] 331 |         let _ = std::mem::replace(&mut *self, oldlevel);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/lib.rs:416:9
[INFO] [stdout]     |
[INFO] [stdout] 416 |         std::mem::replace(&mut *self, oldlevel);
[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] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 416 |         let _ = std::mem::replace(&mut *self, oldlevel);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.22s
[INFO] running `Command { std: "docker" "inspect" "89751b5f13afc6b454c17867a8612fb222ff71e3a323e564e3a4e9bc7ac70bd3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "89751b5f13afc6b454c17867a8612fb222ff71e3a323e564e3a4e9bc7ac70bd3", kill_on_drop: false }`
[INFO] [stdout] 89751b5f13afc6b454c17867a8612fb222ff71e3a323e564e3a4e9bc7ac70bd3