[INFO] fetching crate qcollect-traits 0.7.4...
[INFO] testing qcollect-traits-0.7.4 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate qcollect-traits 0.7.4 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate qcollect-traits 0.7.4 on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate qcollect-traits 0.7.4
[INFO] finished tweaking crates.io crate qcollect-traits 0.7.4
[INFO] tweaked toml for crates.io crate qcollect-traits 0.7.4 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 0eb9d20db065552d35cead07219f9f11f71fb482b2363123216fd9a9b87a7439
[INFO] running `Command { std: "docker" "start" "-a" "0eb9d20db065552d35cead07219f9f11f71fb482b2363123216fd9a9b87a7439", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0eb9d20db065552d35cead07219f9f11f71fb482b2363123216fd9a9b87a7439", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0eb9d20db065552d35cead07219f9f11f71fb482b2363123216fd9a9b87a7439", kill_on_drop: false }`
[INFO] [stdout] 0eb9d20db065552d35cead07219f9f11f71fb482b2363123216fd9a9b87a7439
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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=warn" "-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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 831bea444c96228c08b0a22504f6f3522e1eb70826da2a681d1e89f1792c12de
[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" "831bea444c96228c08b0a22504f6f3522e1eb70826da2a681d1e89f1792c12de", kill_on_drop: false }`
[INFO] [stderr]    Compiling vec_map v0.3.0
[INFO] [stderr]    Compiling qcollect-traits v0.7.4 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:51:1
[INFO] [stdout]    |
[INFO] [stdout] 51 | / #![feature(
[INFO] [stdout] 52 | |     associated_type_defaults,
[INFO] [stdout] 53 | |     collections, 
[INFO] [stdout] 54 | |     collections_bound, 
[INFO] [stdout] 55 | |     btree_range, 
[INFO] [stdout] 56 | |     drain,
[INFO] [stdout] 57 | | )]
[INFO] [stdout]    | |__^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0275]: overflow evaluating the requirement `<Self as traits::_Iterate<'a>>::Item == _`
[INFO] [stdout]   --> src/traits.rs:70:5
[INFO] [stdout]    |
[INFO] [stdout] 70 |     type Item = <Self::Iter as Iterator>::Item;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0275, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0275`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `qcollect-traits`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "831bea444c96228c08b0a22504f6f3522e1eb70826da2a681d1e89f1792c12de", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "831bea444c96228c08b0a22504f6f3522e1eb70826da2a681d1e89f1792c12de", kill_on_drop: false }`
[INFO] [stdout] 831bea444c96228c08b0a22504f6f3522e1eb70826da2a681d1e89f1792c12de