[INFO] cloning repository https://github.com/xtbl/rust_hello
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/xtbl/rust_hello" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 75c9b6aff10b3b0b54b07520ccb1fec6abf9b43b
[INFO] building xtbl/rust_hello against master#44f415c1d617ebc7b931a243b7b321ef8a6ca47c for pr-142134-abi-ast-error
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxtbl%2Frust_hello" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/xtbl/rust_hello on toolchain 44f415c1d617ebc7b931a243b7b321ef8a6ca47c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/xtbl/rust_hello
[INFO] finished tweaking git repo https://github.com/xtbl/rust_hello
[INFO] tweaked toml for git repo https://github.com/xtbl/rust_hello written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/xtbl/rust_hello 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" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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:eea15d5475069c3ef791f10c2c6b5af2ee421ef2da1e680ecce1cba46243983b" "/opt/rustwide/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2964e76915da591c0271a56ede7c678c957c085e2d56fff9e67b4ef55d667ed2
[INFO] running `Command { std: "docker" "start" "-a" "2964e76915da591c0271a56ede7c678c957c085e2d56fff9e67b4ef55d667ed2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2964e76915da591c0271a56ede7c678c957c085e2d56fff9e67b4ef55d667ed2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2964e76915da591c0271a56ede7c678c957c085e2d56fff9e67b4ef55d667ed2", kill_on_drop: false }`
[INFO] [stdout] 2964e76915da591c0271a56ede7c678c957c085e2d56fff9e67b4ef55d667ed2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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=warn" "-e" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:eea15d5475069c3ef791f10c2c6b5af2ee421ef2da1e680ecce1cba46243983b" "/opt/rustwide/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6b3001a1a2b43ba1b4e52289d46f656fdbe8e2f2788a9967b308dc2968120e23
[INFO] running `Command { std: "docker" "start" "-a" "6b3001a1a2b43ba1b4e52289d46f656fdbe8e2f2788a9967b308dc2968120e23", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling getrandom v0.2.2
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling ppv-lite86 v0.2.10
[INFO] [stderr]    Compiling rand_core v0.6.2
[INFO] [stderr]    Compiling rand_chacha v0.3.0
[INFO] [stderr]    Compiling rand v0.8.3
[INFO] [stderr]    Compiling hello_world v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let mut word_freqs = insert_words(splitted);
[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] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.34s
[INFO] running `Command { std: "docker" "inspect" "6b3001a1a2b43ba1b4e52289d46f656fdbe8e2f2788a9967b308dc2968120e23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b3001a1a2b43ba1b4e52289d46f656fdbe8e2f2788a9967b308dc2968120e23", kill_on_drop: false }`
[INFO] [stdout] 6b3001a1a2b43ba1b4e52289d46f656fdbe8e2f2788a9967b308dc2968120e23
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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=warn" "-e" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:eea15d5475069c3ef791f10c2c6b5af2ee421ef2da1e680ecce1cba46243983b" "/opt/rustwide/cargo-home/bin/cargo" "+44f415c1d617ebc7b931a243b7b321ef8a6ca47c" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b2c46b5d0968ac7d0dba35094114a4cffbdfc3394188b8946d76d27d38eb1cbb
[INFO] running `Command { std: "docker" "start" "-a" "b2c46b5d0968ac7d0dba35094114a4cffbdfc3394188b8946d76d27d38eb1cbb", kill_on_drop: false }`
[INFO] [stderr]    Compiling hello_world v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let mut word_freqs = insert_words(splitted);
[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] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.28s
[INFO] running `Command { std: "docker" "inspect" "b2c46b5d0968ac7d0dba35094114a4cffbdfc3394188b8946d76d27d38eb1cbb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b2c46b5d0968ac7d0dba35094114a4cffbdfc3394188b8946d76d27d38eb1cbb", kill_on_drop: false }`
[INFO] [stdout] b2c46b5d0968ac7d0dba35094114a4cffbdfc3394188b8946d76d27d38eb1cbb