[INFO] fetching crate hamt-rs 0.3.0...
[INFO] checking hamt-rs-0.3.0 against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] extracting crate hamt-rs 0.3.0 into /workspace/builds/worker-0-tc1/source
[INFO] validating manifest of crates.io crate hamt-rs 0.3.0 on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate hamt-rs 0.3.0
[INFO] finished tweaking crates.io crate hamt-rs 0.3.0
[INFO] tweaked toml for crates.io crate hamt-rs 0.3.0 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 11 packages
[INFO] [stderr]       Adding rand v0.3.23 (latest: v0.8.5)
[INFO] [stderr]       Adding rand v0.4.6 (latest: v0.8.5)
[INFO] [stderr]       Adding rand_core v0.3.1 (latest: v0.6.4)
[INFO] [stderr]       Adding rand_core v0.4.2 (latest: v0.6.4)
[INFO] [stderr]       Adding rdrand v0.4.0 (latest: v0.8.3)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2eca3ce92c52894912532c2fec3537d5fcdddbf5f34a7193129d83376ab7acd9
[INFO] running `Command { std: "docker" "start" "-a" "2eca3ce92c52894912532c2fec3537d5fcdddbf5f34a7193129d83376ab7acd9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2eca3ce92c52894912532c2fec3537d5fcdddbf5f34a7193129d83376ab7acd9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2eca3ce92c52894912532c2fec3537d5fcdddbf5f34a7193129d83376ab7acd9", kill_on_drop: false }`
[INFO] [stdout] 2eca3ce92c52894912532c2fec3537d5fcdddbf5f34a7193129d83376ab7acd9
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 57fb851a9593d1706c26707ac6f5ddb5dc1d4336f68a9f605cf599504934133e
[INFO] running `Command { std: "docker" "start" "-a" "57fb851a9593d1706c26707ac6f5ddb5dc1d4336f68a9f605cf599504934133e", kill_on_drop: false }`
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking hamt-rs v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Default` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 32 | use std::default::Default;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/385fa9d845dd326c6bbfd58c22244215e431948a/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `Default` is already defined here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `libc` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:38:5
[INFO] [stdout]    |
[INFO] [stdout] 38 | use libc;
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/lib.rs:29:1
[INFO] [stdout]    |
[INFO] [stdout] 29 | extern crate libc;
[INFO] [stdout]    | ------------------ the item `libc` is already imported here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Default` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 32 | use std::default::Default;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/385fa9d845dd326c6bbfd58c22244215e431948a/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `Default` is already defined here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `libc` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:38:5
[INFO] [stdout]    |
[INFO] [stdout] 38 | use libc;
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/lib.rs:29:1
[INFO] [stdout]    |
[INFO] [stdout] 29 | extern crate libc;
[INFO] [stdout]    | ------------------ the item `libc` is already imported here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `rand` is imported redundantly
[INFO] [stdout]   --> src/testing.rs:21:12
[INFO] [stdout]    |
[INFO] [stdout] 21 | use rand::{self, Rng};
[INFO] [stdout]    |            ^^^^
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/lib.rs:31:1
[INFO] [stdout]    |
[INFO] [stdout] 31 | extern crate rand;
[INFO] [stdout]    | ------------------ the item `rand` is already imported here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]    --> benches/benches.rs:165:9
[INFO] [stdout]     |
[INFO] [stdout] 165 |         map.clone();
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 165 |         let _ = map.clone();
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.96s
[INFO] running `Command { std: "docker" "inspect" "57fb851a9593d1706c26707ac6f5ddb5dc1d4336f68a9f605cf599504934133e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "57fb851a9593d1706c26707ac6f5ddb5dc1d4336f68a9f605cf599504934133e", kill_on_drop: false }`
[INFO] [stdout] 57fb851a9593d1706c26707ac6f5ddb5dc1d4336f68a9f605cf599504934133e
[INFO] checking hamt-rs-0.3.0 against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] extracting crate hamt-rs 0.3.0 into /workspace/builds/worker-0-tc2/source
[INFO] validating manifest of crates.io crate hamt-rs 0.3.0 on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate hamt-rs 0.3.0
[INFO] finished tweaking crates.io crate hamt-rs 0.3.0
[INFO] tweaked toml for crates.io crate hamt-rs 0.3.0 written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5d2ee1a5afef6f9ce14e151c276b6f662c052fd017148cc7c2941f2744411908
[INFO] running `Command { std: "docker" "start" "-a" "5d2ee1a5afef6f9ce14e151c276b6f662c052fd017148cc7c2941f2744411908", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5d2ee1a5afef6f9ce14e151c276b6f662c052fd017148cc7c2941f2744411908", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5d2ee1a5afef6f9ce14e151c276b6f662c052fd017148cc7c2941f2744411908", kill_on_drop: false }`
[INFO] [stdout] 5d2ee1a5afef6f9ce14e151c276b6f662c052fd017148cc7c2941f2744411908
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 93ab26652a161543e08d54768db7c853382ab31a59ee736c49dc606a232916af
[INFO] running `Command { std: "docker" "start" "-a" "93ab26652a161543e08d54768db7c853382ab31a59ee736c49dc606a232916af", kill_on_drop: false }`
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking hamt-rs v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Default` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 32 | use std::default::Default;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/645bb72776a6a56a1a8f52631a44bd082b2ba509/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `Default` is already defined here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `libc` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:38:5
[INFO] [stdout]    |
[INFO] [stdout] 38 | use libc;
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/lib.rs:29:1
[INFO] [stdout]    |
[INFO] [stdout] 29 | extern crate libc;
[INFO] [stdout]    | ------------------ the item `libc` is already imported here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Default` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 32 | use std::default::Default;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/645bb72776a6a56a1a8f52631a44bd082b2ba509/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `Default` is already defined here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `libc` is imported redundantly
[INFO] [stdout]   --> src/hamt.rs:38:5
[INFO] [stdout]    |
[INFO] [stdout] 38 | use libc;
[INFO] [stdout]    |     ^^^^
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/lib.rs:29:1
[INFO] [stdout]    |
[INFO] [stdout] 29 | extern crate libc;
[INFO] [stdout]    | ------------------ the item `libc` is already imported here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `rand` is imported redundantly
[INFO] [stdout]   --> src/testing.rs:21:12
[INFO] [stdout]    |
[INFO] [stdout] 21 | use rand::{self, Rng};
[INFO] [stdout]    |            ^^^^
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/lib.rs:31:1
[INFO] [stdout]    |
[INFO] [stdout] 31 | extern crate rand;
[INFO] [stdout]    | ------------------ the item `rand` is already imported here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]    --> benches/benches.rs:165:9
[INFO] [stdout]     |
[INFO] [stdout] 165 |         map.clone();
[INFO] [stdout]     |         ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 165 |         let _ = map.clone();
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.79s
[INFO] running `Command { std: "docker" "inspect" "93ab26652a161543e08d54768db7c853382ab31a59ee736c49dc606a232916af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "93ab26652a161543e08d54768db7c853382ab31a59ee736c49dc606a232916af", kill_on_drop: false }`
[INFO] [stdout] 93ab26652a161543e08d54768db7c853382ab31a59ee736c49dc606a232916af