[INFO] cloning repository https://github.com/faceplate-kleo/cablecar
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/faceplate-kleo/cablecar" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffaceplate-kleo%2Fcablecar", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffaceplate-kleo%2Fcablecar'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1f049a015fc17db04c70be5b8500c49d375251ce
[INFO] building faceplate-kleo/cablecar against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffaceplate-kleo%2Fcablecar" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/faceplate-kleo/cablecar on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/faceplate-kleo/cablecar
[INFO] finished tweaking git repo https://github.com/faceplate-kleo/cablecar
[INFO] tweaked toml for git repo https://github.com/faceplate-kleo/cablecar written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/faceplate-kleo/cablecar already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 869c9a51d4f81e88615173e76f7352d0a970a408071c2ca64bd87e0da46fc102
[INFO] running `Command { std: "docker" "start" "-a" "869c9a51d4f81e88615173e76f7352d0a970a408071c2ca64bd87e0da46fc102", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "869c9a51d4f81e88615173e76f7352d0a970a408071c2ca64bd87e0da46fc102", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "869c9a51d4f81e88615173e76f7352d0a970a408071c2ca64bd87e0da46fc102", kill_on_drop: false }`
[INFO] [stdout] 869c9a51d4f81e88615173e76f7352d0a970a408071c2ca64bd87e0da46fc102
[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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4b1a6e6d2962af22fd4fe3e3a5d6d1e9fdda75eeec34a63483bec5ba74b84607
[INFO] running `Command { std: "docker" "start" "-a" "4b1a6e6d2962af22fd4fe3e3a5d6d1e9fdda75eeec34a63483bec5ba74b84607", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.159
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling getrandom v0.2.15
[INFO] [stderr]    Compiling uuid v1.11.0
[INFO] [stderr]    Compiling cablecar v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:75:18
[INFO] [stdout]    |
[INFO] [stdout] 75 |             Some(mut link) => {
[INFO] [stdout]    |                  ----^^^^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:118:17
[INFO] [stdout]     |
[INFO] [stdout] 118 |             let mut curr = self.read_byte(SERIAL_START as u16).unwrap();
[INFO] [stdout]     |                 ----^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.78s
[INFO] running `Command { std: "docker" "inspect" "4b1a6e6d2962af22fd4fe3e3a5d6d1e9fdda75eeec34a63483bec5ba74b84607", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b1a6e6d2962af22fd4fe3e3a5d6d1e9fdda75eeec34a63483bec5ba74b84607", kill_on_drop: false }`
[INFO] [stdout] 4b1a6e6d2962af22fd4fe3e3a5d6d1e9fdda75eeec34a63483bec5ba74b84607
[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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 91d2ea170a80fac0ccc34de27bf44b4ad11a2bab30beb670d56cbda517eb378e
[INFO] running `Command { std: "docker" "start" "-a" "91d2ea170a80fac0ccc34de27bf44b4ad11a2bab30beb670d56cbda517eb378e", kill_on_drop: false }`
[INFO] [stderr]    Compiling cablecar v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:75:18
[INFO] [stdout]    |
[INFO] [stdout] 75 |             Some(mut link) => {
[INFO] [stdout]    |                  ----^^^^
[INFO] [stdout]    |                  |
[INFO] [stdout]    |                  help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:118:17
[INFO] [stdout]     |
[INFO] [stdout] 118 |             let mut curr = self.read_byte(SERIAL_START as u16).unwrap();
[INFO] [stdout]     |                 ----^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.31s
[INFO] running `Command { std: "docker" "inspect" "91d2ea170a80fac0ccc34de27bf44b4ad11a2bab30beb670d56cbda517eb378e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "91d2ea170a80fac0ccc34de27bf44b4ad11a2bab30beb670d56cbda517eb378e", kill_on_drop: false }`
[INFO] [stdout] 91d2ea170a80fac0ccc34de27bf44b4ad11a2bab30beb670d56cbda517eb378e