[INFO] fetching crate letsgo 0.0.1...
[INFO] checking letsgo-0.0.1 against master#a5f164faad4a2fed606b8160fd7ecd2d5cbba381 for pr-84920
[INFO] extracting crate letsgo 0.0.1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate letsgo 0.0.1 on toolchain a5f164faad4a2fed606b8160fd7ecd2d5cbba381
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate letsgo 0.0.1
[INFO] finished tweaking crates.io crate letsgo 0.0.1
[INFO] tweaked toml for crates.io crate letsgo 0.0.1 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c6653f86fb20d0f81b7f23d8373577f7f10f8ad453a97af373b63449e0daba3a
[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" "c6653f86fb20d0f81b7f23d8373577f7f10f8ad453a97af373b63449e0daba3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c6653f86fb20d0f81b7f23d8373577f7f10f8ad453a97af373b63449e0daba3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c6653f86fb20d0f81b7f23d8373577f7f10f8ad453a97af373b63449e0daba3a", kill_on_drop: false }`
[INFO] [stdout] c6653f86fb20d0f81b7f23d8373577f7f10f8ad453a97af373b63449e0daba3a
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b09152528785949803a5dcaf0ca4a065b50873708cb78c0a3646fb82c7331a92
[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" "b09152528785949803a5dcaf0ca4a065b50873708cb78c0a3646fb82c7331a92", kill_on_drop: false }`
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking futures v0.1.31
[INFO] [stderr]     Checking byteorder v1.4.3
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling proc-macro-nested v0.1.7
[INFO] [stderr]     Checking ppv-lite86 v0.2.10
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]     Checking fnv v1.0.7
[INFO] [stderr]     Checking async-ready v3.0.0
[INFO] [stderr]     Checking async-datagram v3.0.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.6
[INFO] [stderr]     Checking lock_api v0.3.4
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]     Checking rand_jitter v0.1.4
[INFO] [stderr]    Compiling backtrace v0.3.58
[INFO] [stderr]     Checking lru-cache v0.1.2
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking getrandom v0.1.16
[INFO] [stderr]     Checking net2 v0.2.37
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking hostname v0.3.1
[INFO] [stderr]     Checking socket2 v0.3.19
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]     Checking rand_chacha v0.1.1
[INFO] [stderr]     Checking rand_pcg v0.1.2
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking resolv-conf v0.6.3
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]     Checking mio v0.6.23
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking crossbeam-queue v0.2.3
[INFO] [stderr]     Checking crossbeam-channel v0.4.4
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking tokio-io v0.1.13
[INFO] [stderr]     Checking tokio-executor v0.1.10
[INFO] [stderr]     Checking tokio-sync v0.1.8
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking tokio-timer v0.2.13
[INFO] [stderr]     Checking tokio-current-thread v0.1.7
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]     Checking tokio-threadpool v0.1.18
[INFO] [stderr]     Checking crossbeam v0.7.3
[INFO] [stderr]     Checking tokio-reactor v0.1.12
[INFO] [stderr]     Checking tokio-codec v0.1.2
[INFO] [stderr]     Checking tokio-tcp v0.1.4
[INFO] [stderr]     Checking tokio-udp v0.1.6
[INFO] [stderr]     Checking tokio-uds v0.2.7
[INFO] [stderr]     Checking tokio-fs v0.1.7
[INFO] [stderr]     Checking tokio v0.1.22
[INFO] [stderr]    Compiling futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling enum-as-inner v0.2.1
[INFO] [stderr]    Compiling synstructure v0.12.4
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling runtime-attributes v0.3.0-alpha.6
[INFO] [stderr]     Checking futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking runtime-raw v0.3.0-alpha.5
[INFO] [stderr]     Checking juliex v0.3.0-alpha.8
[INFO] [stderr]     Checking romio v0.3.0-alpha.10
[INFO] [stderr]     Checking futures-timer v0.3.0
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]     Checking runtime-tokio v0.3.0-alpha.6
[INFO] [stderr]     Checking trust-dns-proto v0.7.4
[INFO] [stderr]     Checking runtime-native v0.3.0-alpha.6
[INFO] [stderr]     Checking runtime v0.3.0-alpha.7
[INFO] [stderr]     Checking trust-dns-resolver v0.11.1
[INFO] [stderr]     Checking letsgo v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary `unsafe` block
[INFO] [stdout]   --> src/main.rs:14:20
[INFO] [stdout]    |
[INFO] [stdout] 14 |     println!("{}", unsafe { std::intrinsics::type_name::<T>() });
[INFO] [stdout]    |                    ^^^^^^ unnecessary `unsafe` block
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_unsafe)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `print_type_of`
[INFO] [stdout]   --> src/main.rs:13:4
[INFO] [stdout]    |
[INFO] [stdout] 13 | fn print_type_of<T>(_: &T) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `async_await` has been stable since 1.39.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(async_await)]
[INFO] [stdout]   |            ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary `unsafe` block
[INFO] [stdout]   --> src/main.rs:14:20
[INFO] [stdout]    |
[INFO] [stdout] 14 |     println!("{}", unsafe { std::intrinsics::type_name::<T>() });
[INFO] [stdout]    |                    ^^^^^^ unnecessary `unsafe` block
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_unsafe)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `print_type_of`
[INFO] [stdout]   --> src/main.rs:13:4
[INFO] [stdout]    |
[INFO] [stdout] 13 | fn print_type_of<T>(_: &T) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `async_await` has been stable since 1.39.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(async_await)]
[INFO] [stdout]   |            ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 13s
[INFO] running `Command { std: "docker" "inspect" "b09152528785949803a5dcaf0ca4a065b50873708cb78c0a3646fb82c7331a92", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b09152528785949803a5dcaf0ca4a065b50873708cb78c0a3646fb82c7331a92", kill_on_drop: false }`
[INFO] [stdout] b09152528785949803a5dcaf0ca4a065b50873708cb78c0a3646fb82c7331a92