[INFO] updating cached repository calebwin/fern
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/calebwin/fern
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/calebwin/fern" "work/ex/beta-1.38-1/sources/1.37.0/gh/calebwin/fern"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/calebwin/fern'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/calebwin/fern" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/calebwin/fern"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/calebwin/fern'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 9e5da73a0152faa92f4cf96b504e42d82d9448f4
[INFO] sha for GitHub repo calebwin/fern: 9e5da73a0152faa92f4cf96b504e42d82d9448f4
[INFO] validating manifest of calebwin/fern 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 calebwin/fern 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 calebwin/fern
[INFO] finished frobbing calebwin/fern
[INFO] frobbed toml for calebwin/fern written to work/ex/beta-1.38-1/sources/1.37.0/gh/calebwin/fern/Cargo.toml
[INFO] started frobbing calebwin/fern
[INFO] finished frobbing calebwin/fern
[INFO] frobbed toml for calebwin/fern written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/calebwin/fern/Cargo.toml
[INFO] crate calebwin/fern 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 calebwin/fern 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-7/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/calebwin/fern:/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] e700210ebfc3bdc1fa93a3fd3e44a26360677876138de22c8477255f4a82f3b1
[INFO] running `"docker" "start" "-a" "e700210ebfc3bdc1fa93a3fd3e44a26360677876138de22c8477255f4a82f3b1"`
[INFO] [stderr]    Compiling libc v0.2.48
[INFO] [stderr]    Compiling backtrace-sys v0.1.28
[INFO] [stderr]    Compiling backtrace v0.3.13
[INFO] [stderr]    Compiling error-chain v0.12.0
[INFO] [stderr]    Compiling rsmt2 v0.10.0
[INFO] [stderr]    Compiling fern v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `SmtRes`
[INFO] [stderr]  --> src/main.rs:4:13
[INFO] [stderr]   |
[INFO] [stderr] 4 | use rsmt2::{SmtRes, Solver};
[INFO] [stderr]   |             ^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error[E0277]: `rsmt2::example::simple::Cst` doesn't implement `std::fmt::Debug`
[INFO] [stderr]   --> src/main.rs:32:26
[INFO] [stderr]    |
[INFO] [stderr] 32 |         println!("{:?}", model);
[INFO] [stderr]    |                          ^^^^^ `rsmt2::example::simple::Cst` cannot be formatted using `{:?}` because it doesn't implement `std::fmt::Debug`
[INFO] [stderr]    |
[INFO] [stderr]    = help: the trait `std::fmt::Debug` is not implemented for `rsmt2::example::simple::Cst`
[INFO] [stderr]    = note: required because of the requirements on the impl of `std::fmt::Debug` for `(std::string::String, std::string::String, rsmt2::example::simple::Cst)`
[INFO] [stderr]    = note: required because of the requirements on the impl of `std::fmt::Debug` for `std::vec::Vec<(std::string::String, std::string::String, rsmt2::example::simple::Cst)>`
[INFO] [stderr]    = note: required by `std::fmt::Debug::fmt`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0277`.
[INFO] [stderr] error: Could not compile `fern`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "e700210ebfc3bdc1fa93a3fd3e44a26360677876138de22c8477255f4a82f3b1"`
[INFO] running `"docker" "rm" "-f" "e700210ebfc3bdc1fa93a3fd3e44a26360677876138de22c8477255f4a82f3b1"`
[INFO] [stdout] e700210ebfc3bdc1fa93a3fd3e44a26360677876138de22c8477255f4a82f3b1