[INFO] fetching crate wlambda 0.6.2...
[INFO] checking wlambda-0.6.2 against try#d990716b6a1fdde1300748828a9c9e79dfd0b898 for pr-74846
[INFO] extracting crate wlambda 0.6.2 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate wlambda 0.6.2 on toolchain d990716b6a1fdde1300748828a9c9e79dfd0b898
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate wlambda 0.6.2
[INFO] finished tweaking crates.io crate wlambda 0.6.2
[INFO] tweaked toml for crates.io crate wlambda 0.6.2 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate crates.io crate wlambda 0.6.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "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-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a30471ccf47aecf72566281b0fa90d735dfd35392a13281681ca6522ca53024b
[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" "a30471ccf47aecf72566281b0fa90d735dfd35392a13281681ca6522ca53024b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a30471ccf47aecf72566281b0fa90d735dfd35392a13281681ca6522ca53024b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a30471ccf47aecf72566281b0fa90d735dfd35392a13281681ca6522ca53024b", kill_on_drop: false }`
[INFO] [stdout] a30471ccf47aecf72566281b0fa90d735dfd35392a13281681ca6522ca53024b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 26323eb8514ddb8b361b06bd3b537fa97ea245ee3c6f1916bb4968e9701da91c
[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" "26323eb8514ddb8b361b06bd3b537fa97ea245ee3c6f1916bb4968e9701da91c", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.19
[INFO] [stderr]    Compiling syn v1.0.34
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]     Checking unicode-segmentation v1.6.0
[INFO] [stderr]     Checking regex-syntax v0.6.18
[INFO] [stderr]     Checking utf8parse v0.2.0
[INFO] [stderr]     Checking fnv v1.0.7
[INFO] [stderr]     Checking thread_local v1.0.1
[INFO] [stderr]     Checking memchr v2.3.3
[INFO] [stderr]     Checking time v0.1.43
[INFO] [stderr]     Checking dirs-next v1.0.1
[INFO] [stderr]     Checking aho-corasick v0.7.13
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]     Checking nix v0.17.0
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]     Checking rmp v0.8.9
[INFO] [stderr]     Checking regex v1.3.9
[INFO] [stderr]     Checking chrono v0.4.13
[INFO] [stderr]     Checking rustyline v6.2.0
[INFO] [stderr]    Compiling serde_derive v1.0.114
[INFO] [stderr]     Checking serde v1.0.114
[INFO] [stderr]     Checking rmp-serde v0.14.3
[INFO] [stderr]     Checking serde_json v1.0.56
[INFO] [stderr]     Checking wlambda v0.6.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:463:9
[INFO] [stdout]     |
[INFO] [stdout] 463 |         std::mem::replace(&mut self.current_self, old_self);
[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/vval.rs:871:17
[INFO] [stdout]     |
[INFO] [stdout] 871 |                 std::mem::replace(&mut self.loop_info, li);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:874:17
[INFO] [stdout]     |
[INFO] [stdout] 874 |                 std::mem::replace(&mut self.accum_fun, fun);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:875:17
[INFO] [stdout]     |
[INFO] [stdout] 875 |                 std::mem::replace(&mut self.accum_val, val);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:878:17
[INFO] [stdout]     |
[INFO] [stdout] 878 |                 std::mem::replace(&mut self.current_self, slf);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:881:17
[INFO] [stdout]     |
[INFO] [stdout] 881 |                 std::mem::replace(&mut self.iter, i);
[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: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:463:9
[INFO] [stdout]     |
[INFO] [stdout] 463 |         std::mem::replace(&mut self.current_self, old_self);
[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/vval.rs:871:17
[INFO] [stdout]     |
[INFO] [stdout] 871 |                 std::mem::replace(&mut self.loop_info, li);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:874:17
[INFO] [stdout]     |
[INFO] [stdout] 874 |                 std::mem::replace(&mut self.accum_fun, fun);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:875:17
[INFO] [stdout]     |
[INFO] [stdout] 875 |                 std::mem::replace(&mut self.accum_val, val);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:878:17
[INFO] [stdout]     |
[INFO] [stdout] 878 |                 std::mem::replace(&mut self.current_self, slf);
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vval.rs:881:17
[INFO] [stdout]     |
[INFO] [stdout] 881 |                 std::mem::replace(&mut self.iter, i);
[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: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 10s
[INFO] running `Command { std: "docker" "inspect" "26323eb8514ddb8b361b06bd3b537fa97ea245ee3c6f1916bb4968e9701da91c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "26323eb8514ddb8b361b06bd3b537fa97ea245ee3c6f1916bb4968e9701da91c", kill_on_drop: false }`
[INFO] [stdout] 26323eb8514ddb8b361b06bd3b537fa97ea245ee3c6f1916bb4968e9701da91c