[INFO] updating cached repository https://github.com/VitalyAnkh/learn_error_handling
[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] a9cf67b08bbfba5b416953d982e1a8eada6ad2f8
[INFO] testing VitalyAnkh/learn_error_handling against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2FVitalyAnkh%2Flearn_error_handling" "work/builds/worker-2/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/VitalyAnkh/learn_error_handling 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/VitalyAnkh/learn_error_handling
[INFO] finished tweaking git repo https://github.com/VitalyAnkh/learn_error_handling
[INFO] tweaked toml for git repo https://github.com/VitalyAnkh/learn_error_handling written to work/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/VitalyAnkh/learn_error_handling 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-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/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] d3be25e9c07970c429d2237e51b71abd13130453920b9a1a0238abde8614f9dd
[INFO] running `"docker" "start" "-a" "d3be25e9c07970c429d2237e51b71abd13130453920b9a1a0238abde8614f9dd"`
[INFO] [stderr]    Compiling learn_error_handling v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused imports: `Cons`, `Nil`
[INFO] [stderr]  --> src/smart_pointer/rc.rs:7:18
[INFO] [stderr]   |
[INFO] [stderr] 7 | use self::List::{Cons,Nil};
[INFO] [stderr]   |                  ^^^^ ^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Guess`
[INFO] [stderr]  --> src/read/mod.rs:5:1
[INFO] [stderr]   |
[INFO] [stderr] 5 | struct Guess {
[INFO] [stderr]   | ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/read/mod.rs:10:5
[INFO] [stderr]    |
[INFO] [stderr] 10 |     fn new(value: u32) -> Guess {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `List`
[INFO] [stderr]  --> src/smart_pointer/rc.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | enum List{
[INFO] [stderr]   | ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: comparison is useless due to type limits
[INFO] [stderr]   --> src/read/mod.rs:11:12
[INFO] [stderr]    |
[INFO] [stderr] 11 |         if value < 0 || value > 100 {
[INFO] [stderr]    |            ^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_comparisons)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.93s
[INFO] running `"docker" "inspect" "d3be25e9c07970c429d2237e51b71abd13130453920b9a1a0238abde8614f9dd"`
[INFO] running `"docker" "rm" "-f" "d3be25e9c07970c429d2237e51b71abd13130453920b9a1a0238abde8614f9dd"`
[INFO] [stdout] d3be25e9c07970c429d2237e51b71abd13130453920b9a1a0238abde8614f9dd
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/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" "test" "--frozen" "--no-run"`
[INFO] [stdout] e481a1be905d23053bf3086c50b004c0d3b78301c4b0ddbd11fe9037d6e630be
[INFO] running `"docker" "start" "-a" "e481a1be905d23053bf3086c50b004c0d3b78301c4b0ddbd11fe9037d6e630be"`
[INFO] [stderr]    Compiling learn_error_handling v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> tests/integration_test.rs:11:9
[INFO] [stderr]    |
[INFO] [stderr] 11 |     let y =&a;
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_y`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `it_add_two`
[INFO] [stderr]  --> tests/integration_test.rs:5:1
[INFO] [stderr]   |
[INFO] [stderr] 5 | fn it_add_two(){
[INFO] [stderr]   | ^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `check_borrow_rules`
[INFO] [stderr]  --> tests/integration_test.rs:9:1
[INFO] [stderr]   |
[INFO] [stderr] 9 | fn check_borrow_rules(){
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]   --> src/smart_pointer/rc.rs:12:9
[INFO] [stderr]    |
[INFO] [stderr] 12 |     let b = Cons(2,Rc::clone(&a));
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_b`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]  --> src/smart_pointer/ref_cell.rs:4:13
[INFO] [stderr]   |
[INFO] [stderr] 4 |     let mut y =&a;
[INFO] [stderr]   |             ^ help: consider prefixing with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]  --> src/smart_pointer/ref_cell.rs:4:9
[INFO] [stderr]   |
[INFO] [stderr] 4 |     let mut y =&a;
[INFO] [stderr]   |         ----^
[INFO] [stderr]   |         |
[INFO] [stderr]   |         help: remove this `mut`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `value`
[INFO] [stderr]  --> src/read/mod.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 |     value: u32
[INFO] [stderr]   |     ^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: comparison is useless due to type limits
[INFO] [stderr]   --> src/read/mod.rs:11:12
[INFO] [stderr]    |
[INFO] [stderr] 11 |         if value < 0 || value > 100 {
[INFO] [stderr]    |            ^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_comparisons)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.31s
[INFO] running `"docker" "inspect" "e481a1be905d23053bf3086c50b004c0d3b78301c4b0ddbd11fe9037d6e630be"`
[INFO] running `"docker" "rm" "-f" "e481a1be905d23053bf3086c50b004c0d3b78301c4b0ddbd11fe9037d6e630be"`
[INFO] [stdout] e481a1be905d23053bf3086c50b004c0d3b78301c4b0ddbd11fe9037d6e630be
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/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" "test" "--frozen"`
[INFO] [stdout] aca5824fa9c10f689f73eae3528a5f9639838681d799ddb5d8b2460636eee743
[INFO] running `"docker" "start" "-a" "aca5824fa9c10f689f73eae3528a5f9639838681d799ddb5d8b2460636eee743"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.00s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/learn_error_handling-8fc12f86ae6f81f7
[INFO] [stdout] 
[INFO] [stdout] running 3 tests
[INFO] [stdout] test smart_pointer::ref_cell::check_borrow_rules ... ok
[INFO] [stdout] test smart_pointer::rc::test_rc ... ok
[INFO] [stdout] test read::tests::greater_than_100 ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/learn_error_handling-d4cc734308c55688
[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] [stderr]      Running /opt/rustwide/target/debug/deps/integration_test-535f4fa61058570d
[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] [stderr]    Doc-tests learn_error_handling
[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" "aca5824fa9c10f689f73eae3528a5f9639838681d799ddb5d8b2460636eee743"`
[INFO] running `"docker" "rm" "-f" "aca5824fa9c10f689f73eae3528a5f9639838681d799ddb5d8b2460636eee743"`
[INFO] [stdout] aca5824fa9c10f689f73eae3528a5f9639838681d799ddb5d8b2460636eee743