[INFO] updating cached repository hello2dj/rust-practice
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/hello2dj/rust-practice
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/hello2dj/rust-practice" "work/ex/beta-1.38-1/sources/1.37.0/gh/hello2dj/rust-practice"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/hello2dj/rust-practice'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/hello2dj/rust-practice" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hello2dj/rust-practice"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hello2dj/rust-practice'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] ce0d5883667b72104cdd70b2882319ddf6fdb47a
[INFO] sha for GitHub repo hello2dj/rust-practice: ce0d5883667b72104cdd70b2882319ddf6fdb47a
[INFO] validating manifest of hello2dj/rust-practice 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 hello2dj/rust-practice 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 hello2dj/rust-practice
[INFO] finished frobbing hello2dj/rust-practice
[INFO] frobbed toml for hello2dj/rust-practice written to work/ex/beta-1.38-1/sources/1.37.0/gh/hello2dj/rust-practice/Cargo.toml
[INFO] started frobbing hello2dj/rust-practice
[INFO] finished frobbing hello2dj/rust-practice
[INFO] frobbed toml for hello2dj/rust-practice written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/hello2dj/rust-practice/Cargo.toml
[INFO] crate hello2dj/rust-practice 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 hello2dj/rust-practice against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-5/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/hello2dj/rust-practice:/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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 487d011330c1cafbf7ba16593a12db04e316d496e6c0f5f71d32fe948e4818c7
[INFO] running `"docker" "start" "-a" "487d011330c1cafbf7ba16593a12db04e316d496e6c0f5f71d32fe948e4818c7"`
[INFO] [stderr]    Compiling flate2-crc v0.1.1
[INFO] [stderr]    Compiling num-bigint v0.2.1
[INFO] [stderr]    Compiling bit-vec v0.5.0
[INFO] [stderr]    Compiling atoi v0.2.3
[INFO] [stderr]    Compiling checked v0.5.0
[INFO] [stderr]    Compiling miniz-sys v0.1.11
[INFO] [stderr]    Compiling twox-hash v1.1.1
[INFO] [stderr]    Compiling csv-core v0.1.5
[INFO] [stderr]    Compiling chrono v0.4.6
[INFO] [stderr]    Compiling serde_derive v1.0.87
[INFO] [stderr]    Compiling tokio-reactor v0.1.7
[INFO] [stderr]    Compiling csv v1.0.5
[INFO] [stderr]    Compiling flate2 v1.0.5
[INFO] [stderr]    Compiling tokio-tcp v0.1.2
[INFO] [stderr]    Compiling tokio-udp v0.1.3
[INFO] [stderr]    Compiling tokio-uds v0.2.4
[INFO] [stderr]    Compiling tokio v0.1.13
[INFO] [stderr]    Compiling mysql_common v0.9.2
[INFO] [stderr]    Compiling mysql v14.1.1
[INFO] [stderr]    Compiling future v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/main.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(trace_macros)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/main.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(dbg_macro)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/main.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![feature(try_trait)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::process`
[INFO] [stderr]  --> src/csv.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 | use std::process;
[INFO] [stderr]   |     ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::error::Error`
[INFO] [stderr]  --> src/acronym.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::error::Error;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::iter::FromIterator`
[INFO] [stderr]  --> src/acronym.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::iter::FromIterator;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::borrow::Borrow`
[INFO] [stderr]  --> src/null.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::borrow::Borrow;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `future`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "487d011330c1cafbf7ba16593a12db04e316d496e6c0f5f71d32fe948e4818c7"`
[INFO] running `"docker" "rm" "-f" "487d011330c1cafbf7ba16593a12db04e316d496e6c0f5f71d32fe948e4818c7"`
[INFO] [stdout] 487d011330c1cafbf7ba16593a12db04e316d496e6c0f5f71d32fe948e4818c7