[INFO] updating cached repository https://github.com/duganc/polynomial-rings
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 93f50ef4a3841c0a287666a14f5747d162dfb0d4
[INFO] checking duganc/polynomial-rings against master#2748a9fd93dd1a00a4521f4f16de5befbf77f6cd for pr-62262-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fduganc%2Fpolynomial-rings" "/workspace/builds/worker-7/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/duganc/polynomial-rings on toolchain 2748a9fd93dd1a00a4521f4f16de5befbf77f6cd
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/duganc/polynomial-rings
[INFO] finished tweaking git repo https://github.com/duganc/polynomial-rings
[INFO] tweaked toml for git repo https://github.com/duganc/polynomial-rings written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/duganc/polynomial-rings already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] f8e461b04fe83ab776f07c80c8e3ca69b553a6c5286dd8e4c574a08739136996
[INFO] running `"docker" "start" "-a" "f8e461b04fe83ab776f07c80c8e3ca69b553a6c5286dd8e4c574a08739136996"`
[INFO] [stderr]    Compiling num-bigint v0.2.2
[INFO] [stderr]    Compiling num-traits v0.2.8
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]    Compiling num-complex v0.2.3
[INFO] [stderr]    Compiling num-rational v0.2.2
[INFO] [stderr]    Compiling num-iter v0.1.39
[INFO] [stderr]     Checking num v0.2.0
[INFO] [stderr]     Checking polynomial-rings v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `num::complex::Complex`
[INFO] [stderr]  --> src/ring.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use num::complex::Complex;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `VARIABLE`
[INFO] [stderr]  --> src/ring.rs:6:1
[INFO] [stderr]   |
[INFO] [stderr] 6 | const VARIABLE: &str = "x";
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `zero`
[INFO] [stderr]   --> src/ring.rs:64:2
[INFO] [stderr]    |
[INFO] [stderr] 64 |     pub fn zero() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `get_degree`
[INFO] [stderr]   --> src/ring.rs:68:2
[INFO] [stderr]    |
[INFO] [stderr] 68 |     pub fn get_degree(&self) -> i8 {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `to_string`
[INFO] [stderr]   --> src/ring.rs:75:2
[INFO] [stderr]    |
[INFO] [stderr] 75 |     pub fn to_string(&self) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `to_string_term`
[INFO] [stderr]   --> src/ring.rs:92:2
[INFO] [stderr]    |
[INFO] [stderr] 92 |     fn to_string_term(coefficient: T, variable: String, power: u16) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `to_string_variable`
[INFO] [stderr]   --> src/ring.rs:96:2
[INFO] [stderr]    |
[INFO] [stderr] 96 |     fn to_string_variable(variable: String, power: u16) -> String {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.50s
[INFO] running `"docker" "inspect" "f8e461b04fe83ab776f07c80c8e3ca69b553a6c5286dd8e4c574a08739136996"`
[INFO] running `"docker" "rm" "-f" "f8e461b04fe83ab776f07c80c8e3ca69b553a6c5286dd8e4c574a08739136996"`
[INFO] [stdout] f8e461b04fe83ab776f07c80c8e3ca69b553a6c5286dd8e4c574a08739136996