[INFO] fetching crate chainmap 0.1.2...
[INFO] checking chainmap-0.1.2 against try#99a443d6903f71d521237d8acb5a3016b534d17b for pr-83354
[INFO] extracting crate chainmap 0.1.2 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate chainmap 0.1.2 on toolchain 99a443d6903f71d521237d8acb5a3016b534d17b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+99a443d6903f71d521237d8acb5a3016b534d17b" "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-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+99a443d6903f71d521237d8acb5a3016b534d17b" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+99a443d6903f71d521237d8acb5a3016b534d17b" "fetch" "--locked" "--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-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+99a443d6903f71d521237d8acb5a3016b534d17b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ae694b46f34e0a05aad6d7f703d12a50e4104240dfb221897992de1b5e4296e9
[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" "ae694b46f34e0a05aad6d7f703d12a50e4104240dfb221897992de1b5e4296e9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ae694b46f34e0a05aad6d7f703d12a50e4104240dfb221897992de1b5e4296e9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ae694b46f34e0a05aad6d7f703d12a50e4104240dfb221897992de1b5e4296e9", kill_on_drop: false }`
[INFO] [stdout] ae694b46f34e0a05aad6d7f703d12a50e4104240dfb221897992de1b5e4296e9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+99a443d6903f71d521237d8acb5a3016b534d17b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1bbce40521c92411cfa56577a34170beddfc8eca84d252e99333f7e53d40ccfb
[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" "1bbce40521c92411cfa56577a34170beddfc8eca84d252e99333f7e53d40ccfb", 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: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[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] 
[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: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.61s
[INFO] running `Command { std: "docker" "inspect" "1bbce40521c92411cfa56577a34170beddfc8eca84d252e99333f7e53d40ccfb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1bbce40521c92411cfa56577a34170beddfc8eca84d252e99333f7e53d40ccfb", kill_on_drop: false }`
[INFO] [stdout] 1bbce40521c92411cfa56577a34170beddfc8eca84d252e99333f7e53d40ccfb