[INFO] updating cached repository https://github.com/echochamber/tinkering
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/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] 8e17f3360b516c74c1388059fa3c708a33ac4b6b
[INFO] testing echochamber/tinkering against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fechochamber%2Ftinkering" "work/builds/worker-1/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/echochamber/tinkering on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/echochamber/tinkering
[INFO] finished tweaking git repo https://github.com/echochamber/tinkering
[INFO] tweaked toml for git repo https://github.com/echochamber/tinkering written to work/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/echochamber/tinkering already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-1/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-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" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] 4be0c3bf4835709e009cd4007c8a947ef101b67e66177366e06a8f76ca983637
[INFO] running `"docker" "start" "-a" "4be0c3bf4835709e009cd4007c8a947ef101b67e66177366e06a8f76ca983637"`
[INFO] [stderr]    Compiling backtrace-sys v0.1.16
[INFO] [stderr]    Compiling termion v1.5.1
[INFO] [stderr]    Compiling tokio-io v0.1.4
[INFO] [stderr]    Compiling tokio-core v0.1.10
[INFO] [stderr]    Compiling backtrace v0.3.4
[INFO] [stderr]    Compiling error-chain v0.11.0
[INFO] [stderr]    Compiling echo-edit v0.1.0 (/opt/rustwide/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(io)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]  --> src/main.rs:7:1
[INFO] [stderr]   |
[INFO] [stderr] 7 | #[macro_use]
[INFO] [stderr]   | ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `BufRead`, `Cursor`
[INFO] [stderr]   --> src/main.rs:12:28
[INFO] [stderr]    |
[INFO] [stderr] 12 | use std::io::{Write, Read, BufRead, Cursor, self};
[INFO] [stderr]    |                            ^^^^^^^  ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::char::from_u32`
[INFO] [stderr]   --> src/main.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 | use std::char::from_u32;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `chars` found for type `std::io::Stdin` in the current scope
[INFO] [stderr]   --> src/main.rs:82:32
[INFO] [stderr]    |
[INFO] [stderr] 82 |     for my_char in io::stdin().chars() {
[INFO] [stderr]    |                                ^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0554, E0599.
[INFO] [stderr] For more information about an error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `echo-edit`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "4be0c3bf4835709e009cd4007c8a947ef101b67e66177366e06a8f76ca983637"`
[INFO] running `"docker" "rm" "-f" "4be0c3bf4835709e009cd4007c8a947ef101b67e66177366e06a8f76ca983637"`
[INFO] [stdout] 4be0c3bf4835709e009cd4007c8a947ef101b67e66177366e06a8f76ca983637