[INFO] updating cached repository ahouts/math166-assignment2
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/ahouts/math166-assignment2
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/ahouts/math166-assignment2" "work/ex/beta-1.38-1/sources/1.37.0/gh/ahouts/math166-assignment2"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/ahouts/math166-assignment2'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/ahouts/math166-assignment2" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ahouts/math166-assignment2"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ahouts/math166-assignment2'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 4a89187ef91f6b75d3c9e649207e8b1b98a8efbc
[INFO] sha for GitHub repo ahouts/math166-assignment2: 4a89187ef91f6b75d3c9e649207e8b1b98a8efbc
[INFO] validating manifest of ahouts/math166-assignment2 on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of ahouts/math166-assignment2 on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing ahouts/math166-assignment2
[INFO] finished frobbing ahouts/math166-assignment2
[INFO] frobbed toml for ahouts/math166-assignment2 written to work/ex/beta-1.38-1/sources/1.37.0/gh/ahouts/math166-assignment2/Cargo.toml
[INFO] started frobbing ahouts/math166-assignment2
[INFO] finished frobbing ahouts/math166-assignment2
[INFO] frobbed toml for ahouts/math166-assignment2 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ahouts/math166-assignment2/Cargo.toml
[INFO] crate ahouts/math166-assignment2 already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing ahouts/math166-assignment2 against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ahouts/math166-assignment2:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] 81fe1aa5391286208b303563c98d46996c576b4cd428479728a75bb12acff13d
[INFO] running `"docker" "start" "-a" "81fe1aa5391286208b303563c98d46996c576b4cd428479728a75bb12acff13d"`
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling math166-assignment2 v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: struct is never constructed: `ReverseSub`
[INFO] [stderr]   --> src/mat_eqn_solver.rs:13:1
[INFO] [stderr]    |
[INFO] [stderr] 13 | pub struct ReverseSub<T: UpperTriangle> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.48s
[INFO] running `"docker" "inspect" "81fe1aa5391286208b303563c98d46996c576b4cd428479728a75bb12acff13d"`
[INFO] running `"docker" "rm" "-f" "81fe1aa5391286208b303563c98d46996c576b4cd428479728a75bb12acff13d"`
[INFO] [stdout] 81fe1aa5391286208b303563c98d46996c576b4cd428479728a75bb12acff13d
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ahouts/math166-assignment2:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "test" "--frozen" "--no-run"`
[INFO] [stdout] 4efd99d5468717fc48348dfab69b965074e2a640031727ec616b9506b877d19b
[INFO] running `"docker" "start" "-a" "4efd99d5468717fc48348dfab69b965074e2a640031727ec616b9506b877d19b"`
[INFO] [stderr]    Compiling math166-assignment2 v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: struct is never constructed: `ReverseSub`
[INFO] [stderr]   --> src/mat_eqn_solver.rs:13:1
[INFO] [stderr]    |
[INFO] [stderr] 13 | pub struct ReverseSub<T: UpperTriangle> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.11s
[INFO] running `"docker" "inspect" "4efd99d5468717fc48348dfab69b965074e2a640031727ec616b9506b877d19b"`
[INFO] running `"docker" "rm" "-f" "4efd99d5468717fc48348dfab69b965074e2a640031727ec616b9506b877d19b"`
[INFO] [stdout] 4efd99d5468717fc48348dfab69b965074e2a640031727ec616b9506b877d19b
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ahouts/math166-assignment2:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "test" "--frozen"`
[INFO] [stdout] 72e140262a012b11caf8f07d8822edda01844e9dde262679151455f46c91fef8
[INFO] running `"docker" "start" "-a" "72e140262a012b11caf8f07d8822edda01844e9dde262679151455f46c91fef8"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/math166_assignment2-a0249e7e3352f312
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "72e140262a012b11caf8f07d8822edda01844e9dde262679151455f46c91fef8"`
[INFO] running `"docker" "rm" "-f" "72e140262a012b11caf8f07d8822edda01844e9dde262679151455f46c91fef8"`
[INFO] [stdout] 72e140262a012b11caf8f07d8822edda01844e9dde262679151455f46c91fef8