[INFO] fetching crate rr-mux 0.10.1...
[INFO] checking rr-mux-0.10.1 against master#5e3f1b148db5bfa27fee52464ae1f5d34c49d77b for pr-75502
[INFO] extracting crate rr-mux 0.10.1 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate rr-mux 0.10.1 on toolchain 5e3f1b148db5bfa27fee52464ae1f5d34c49d77b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rr-mux 0.10.1
[INFO] finished tweaking crates.io crate rr-mux 0.10.1
[INFO] tweaked toml for crates.io crate rr-mux 0.10.1 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "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] f82a02f3f5406e5e6aba439b7d516911f6a96545392707275c2f0673e61109e9
[INFO] running `Command { std: "docker" "start" "-a" "f82a02f3f5406e5e6aba439b7d516911f6a96545392707275c2f0673e61109e9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f82a02f3f5406e5e6aba439b7d516911f6a96545392707275c2f0673e61109e9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f82a02f3f5406e5e6aba439b7d516911f6a96545392707275c2f0673e61109e9", kill_on_drop: false }`
[INFO] [stdout] f82a02f3f5406e5e6aba439b7d516911f6a96545392707275c2f0673e61109e9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 29c12424b3abcbd2b4153dbcea898fe69e16939693b78ec9572a2ff1e622099f
[INFO] running `Command { std: "docker" "start" "-a" "29c12424b3abcbd2b4153dbcea898fe69e16939693b78ec9572a2ff1e622099f", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]    Compiling proc-macro-nested v0.1.6
[INFO] [stderr]     Checking futures-core v0.3.5
[INFO] [stderr]    Compiling proc-macro-hack v0.5.18
[INFO] [stderr]     Checking futures-sink v0.3.5
[INFO] [stderr]     Checking once_cell v1.4.1
[INFO] [stderr]     Checking futures-io v0.3.5
[INFO] [stderr]     Checking slab v0.4.2
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking futures-channel v0.3.5
[INFO] [stderr]     Checking futures-task v0.3.5
[INFO] [stderr]    Compiling darling_core v0.10.2
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling async-trait v0.1.39
[INFO] [stderr]    Compiling darling_macro v0.10.2
[INFO] [stderr]    Compiling darling v0.10.2
[INFO] [stderr]    Compiling derive_builder_core v0.9.0
[INFO] [stderr]     Checking pin-project v0.4.23
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]    Compiling derive_builder v0.9.0
[INFO] [stderr]     Checking futures-executor v0.3.5
[INFO] [stderr]     Checking futures v0.3.5
[INFO] [stderr]     Checking rr-mux v0.10.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `ctx_in`
[INFO] [stdout]    --> src/mux.rs:203:13
[INFO] [stdout]     |
[INFO] [stdout] 203 |         let ctx_in = C(50);
[INFO] [stdout]     |             ^^^^^^ help: if this is intentional, prefix it with an underscore: `_ctx_in`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 54.23s
[INFO] running `Command { std: "docker" "inspect" "29c12424b3abcbd2b4153dbcea898fe69e16939693b78ec9572a2ff1e622099f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "29c12424b3abcbd2b4153dbcea898fe69e16939693b78ec9572a2ff1e622099f", kill_on_drop: false }`
[INFO] [stdout] 29c12424b3abcbd2b4153dbcea898fe69e16939693b78ec9572a2ff1e622099f