[INFO] fetching crate rxrust 0.8.3...
[INFO] checking rxrust-0.8.3 against try#d990716b6a1fdde1300748828a9c9e79dfd0b898 for pr-74846
[INFO] extracting crate rxrust 0.8.3 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate rxrust 0.8.3 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 rxrust 0.8.3
[INFO] finished tweaking crates.io crate rxrust 0.8.3
[INFO] tweaked toml for crates.io crate rxrust 0.8.3 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 026e04744cbf6106fdcd009015da17c725cbcb04db0dd8e4d5ad638ff1303eb8
[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" "026e04744cbf6106fdcd009015da17c725cbcb04db0dd8e4d5ad638ff1303eb8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "026e04744cbf6106fdcd009015da17c725cbcb04db0dd8e4d5ad638ff1303eb8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "026e04744cbf6106fdcd009015da17c725cbcb04db0dd8e4d5ad638ff1303eb8", kill_on_drop: false }`
[INFO] [stdout] 026e04744cbf6106fdcd009015da17c725cbcb04db0dd8e4d5ad638ff1303eb8
[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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 58a14bec1419bb0c30ba7e224dfef722551ff146a07ea5e74826cc3c1d940952
[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" "58a14bec1419bb0c30ba7e224dfef722551ff146a07ea5e74826cc3c1d940952", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.74
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking slab v0.4.2
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking float-cmp v0.5.3
[INFO] [stderr]     Checking futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-timer v0.3.0
[INFO] [stderr]     Checking rxrust v0.8.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:26
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(external_doc, specialization, drain_filter, test, decl_macro)]
[INFO] [stdout]   |                          ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:26
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(external_doc, specialization, drain_filter, test, decl_macro)]
[INFO] [stdout]   |                          ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 16.18s
[INFO] running `Command { std: "docker" "inspect" "58a14bec1419bb0c30ba7e224dfef722551ff146a07ea5e74826cc3c1d940952", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "58a14bec1419bb0c30ba7e224dfef722551ff146a07ea5e74826cc3c1d940952", kill_on_drop: false }`
[INFO] [stdout] 58a14bec1419bb0c30ba7e224dfef722551ff146a07ea5e74826cc3c1d940952