[INFO] cloning repository https://github.com/narenkulk/rust-practice
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/narenkulk/rust-practice" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnarenkulk%2Frust-practice", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnarenkulk%2Frust-practice'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0c1d7c43ce33ff86f91618301849253ca197d043
[INFO] checking narenkulk/rust-practice against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnarenkulk%2Frust-practice" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/narenkulk/rust-practice on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/narenkulk/rust-practice
[INFO] finished tweaking git repo https://github.com/narenkulk/rust-practice
[INFO] tweaked toml for git repo https://github.com/narenkulk/rust-practice written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/narenkulk/rust-practice already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr] note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr] note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr] note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded strum v0.17.1
[INFO] [stderr]   Downloaded strum_macros v0.17.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 005f774301528202cd8a181598d778c6c44e2915da46a6f31ccbfad409eb35f3
[INFO] running `Command { std: "docker" "start" "-a" "005f774301528202cd8a181598d778c6c44e2915da46a6f31ccbfad409eb35f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "005f774301528202cd8a181598d778c6c44e2915da46a6f31ccbfad409eb35f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "005f774301528202cd8a181598d778c6c44e2915da46a6f31ccbfad409eb35f3", kill_on_drop: false }`
[INFO] [stdout] 005f774301528202cd8a181598d778c6c44e2915da46a6f31ccbfad409eb35f3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a4c736e81a1e470a83067cce62c13612318867ec8611c99d30d8926d3601c9e8
[INFO] running `Command { std: "docker" "start" "-a" "a4c736e81a1e470a83067cce62c13612318867ec8611c99d30d8926d3601c9e8", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr] note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr] note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr] note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] [stderr]    Compiling serde v1.0.175
[INFO] [stderr]    Compiling unicode-segmentation v1.10.1
[INFO] [stderr]    Compiling serde_json v1.0.103
[INFO] [stderr]    Compiling serde_derive v1.0.175
[INFO] [stderr]     Checking minigrep v0.1.0 (/opt/rustwide/workdir/17_minigrep)
[INFO] [stderr]     Checking strum v0.17.1
[INFO] [stderr]     Checking iterators v0.1.0 (/opt/rustwide/workdir/19_iterators)
[INFO] [stderr]     Checking modules v0.1.0 (/opt/rustwide/workdir/09_modules)
[INFO] [stderr]     Checking generics v0.1.0 (/opt/rustwide/workdir/13_generics)
[INFO] [stderr]     Checking writing_tests v0.1.0 (/opt/rustwide/workdir/16_writing_tests)
[INFO] [stderr]     Checking lifetimes v0.1.0 (/opt/rustwide/workdir/15_lifetimes)
[INFO] [stderr]     Checking ownership v0.1.0 (/opt/rustwide/workdir/03_ownership)
[INFO] [stderr]     Checking smart_pointers v0.1.0 (/opt/rustwide/workdir/20_smart_pointers)
[INFO] [stderr]     Checking getrandom v0.2.10
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]    Compiling quote v1.0.31
[INFO] [stdout] warning: struct `Shoe` is never constructed
[INFO] [stdout]  --> 19_iterators/src/lib.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Shoe {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `shoes_in_size` is never used
[INFO] [stdout]   --> 19_iterators/src/lib.rs:12:4
[INFO] [stdout]    |
[INFO] [stdout] 12 | fn shoes_in_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Rectangle` is never constructed
[INFO] [stdout]  --> 16_writing_tests/src/lib.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Rectangle {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `can_hold` is never used
[INFO] [stdout]   --> 16_writing_tests/src/lib.rs:11:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | impl Rectangle {
[INFO] [stdout]    | -------------- method in this implementation
[INFO] [stdout] 11 |     fn can_hold(self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `modules` is imported redundantly
[INFO] [stdout]  --> 09_modules/src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use modules;
[INFO] [stdout]   |     ^^^^^^^ the item `modules` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> 20_smart_pointers/src/main.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons(i32, Box<List>),
[INFO] [stdout]   |     ---- ^^^  ^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons((), ()),
[INFO] [stdout]   |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `modules` is imported redundantly
[INFO] [stdout]  --> 09_modules/src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use modules;
[INFO] [stdout]   |     ^^^^^^^ the item `modules` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking error_handling v0.1.0 (/opt/rustwide/workdir/12_error_handling)
[INFO] [stdout] warning: the item `writing_tests` is imported redundantly
[INFO] [stdout]  --> 16_writing_tests/tests/integration_tests.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use writing_tests;
[INFO] [stdout]   |     ^^^^^^^^^^^^^ the item `writing_tests` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `value` is never read
[INFO] [stdout]  --> 16_writing_tests/tests/integration_tests.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Guess {
[INFO] [stdout]   |        ----- field in this struct
[INFO] [stdout] 6 |     value: i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `setup` is never used
[INFO] [stdout]  --> 16_writing_tests/tests/common/mod.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn setup() {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `generics` is imported redundantly
[INFO] [stdout]  --> 13_generics/src/main.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use generics::{self, Summary}; // this is the name of the module defined in Cargo.toml file
[INFO] [stdout]   |                ^^^^ the item `generics` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `generics` is imported redundantly
[INFO] [stdout]  --> 13_generics/src/main.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use generics::{self, Summary}; // this is the name of the module defined in Cargo.toml file
[INFO] [stdout]   |                ^^^^ the item `generics` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking closure v0.1.0 (/opt/rustwide/workdir/18_closure)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking slices v0.1.0 (/opt/rustwide/workdir/04_slices)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking stack_heap v0.1.0 (/opt/rustwide/workdir/02_stack_heap)
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking structure v0.1.0 (/opt/rustwide/workdir/07_structure)
[INFO] [stderr]     Checking practice_concepts v0.1.0 (/opt/rustwide/workdir/05_control_flow)
[INFO] [stderr]     Checking vectors v0.1.0 (/opt/rustwide/workdir/10_vectors)
[INFO] [stderr]     Checking traits v0.1.0 (/opt/rustwide/workdir/14_traits)
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> 18_closure/src/main.rs:83:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     struct Rectangle {
[INFO] [stdout]    |            --------- field in this struct
[INFO] [stdout] 82 |         width: u32,
[INFO] [stdout] 83 |         height: u32,
[INFO] [stdout]    |         ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Rectangle` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking str_String v0.1.0 (/opt/rustwide/workdir/06_str_string)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> 20_smart_pointers/src/main.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons(i32, Box<List>),
[INFO] [stdout]   |     ---- ^^^  ^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons((), ()),
[INFO] [stdout]   |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking guessing_game v0.1.0 (/opt/rustwide/workdir/01_guessing_game)
[INFO] [stderr]     Checking guessing_game2 v0.1.0 (/opt/rustwide/workdir/01a_guessing_game)
[INFO] [stderr]    Compiling strum_macros v0.17.1
[INFO] [stderr]     Checking enum_example v0.1.0 (/opt/rustwide/workdir/08_enum_example)
[INFO] [stderr]     Checking hash_map v0.1.0 (/opt/rustwide/workdir/11_hash_map)
[INFO] [stdout] warning: variants `Cent` and `Dollar` are never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout] 7  | enum Coins {
[INFO] [stdout]    |      ----- variants in this enum
[INFO] [stdout] 8  |     Quarter(CANProvince),
[INFO] [stdout] 9  |     Cent,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 10 |     Dollar,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Coins` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv4Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:21:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | struct Ipv4Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv6Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct Ipv6Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `IPAddr` is never used
[INFO] [stdout]   --> 08_enum_example/src/main.rs:25:6
[INFO] [stdout]    |
[INFO] [stdout] 25 | enum IPAddr {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Cent` and `Dollar` are never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout] 7  | enum Coins {
[INFO] [stdout]    |      ----- variants in this enum
[INFO] [stdout] 8  |     Quarter(CANProvince),
[INFO] [stdout] 9  |     Cent,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 10 |     Dollar,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Coins` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv4Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:21:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | struct Ipv4Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv6Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct Ipv6Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `IPAddr` is never used
[INFO] [stdout]   --> 08_enum_example/src/main.rs:25:6
[INFO] [stdout]    |
[INFO] [stdout] 25 | enum IPAddr {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.70s
[INFO] running `Command { std: "docker" "inspect" "a4c736e81a1e470a83067cce62c13612318867ec8611c99d30d8926d3601c9e8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a4c736e81a1e470a83067cce62c13612318867ec8611c99d30d8926d3601c9e8", kill_on_drop: false }`
[INFO] [stdout] a4c736e81a1e470a83067cce62c13612318867ec8611c99d30d8926d3601c9e8
[INFO] checking narenkulk/rust-practice against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnarenkulk%2Frust-practice" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/narenkulk/rust-practice on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/narenkulk/rust-practice
[INFO] finished tweaking git repo https://github.com/narenkulk/rust-practice
[INFO] tweaked toml for git repo https://github.com/narenkulk/rust-practice written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/narenkulk/rust-practice already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr] note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr] note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr] note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e0dbd5281861c9fc61fde1ad0b987fd1b4abc72b44b6d873d441ee72ea094931
[INFO] running `Command { std: "docker" "start" "-a" "e0dbd5281861c9fc61fde1ad0b987fd1b4abc72b44b6d873d441ee72ea094931", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e0dbd5281861c9fc61fde1ad0b987fd1b4abc72b44b6d873d441ee72ea094931", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e0dbd5281861c9fc61fde1ad0b987fd1b4abc72b44b6d873d441ee72ea094931", kill_on_drop: false }`
[INFO] [stdout] e0dbd5281861c9fc61fde1ad0b987fd1b4abc72b44b6d873d441ee72ea094931
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6e96c378ea5f1eb5838c65f67d7129c686baa28b87830414998982c4ca1ea128
[INFO] running `Command { std: "docker" "start" "-a" "6e96c378ea5f1eb5838c65f67d7129c686baa28b87830414998982c4ca1ea128", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr] note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr] note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr] note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] [stderr]    Compiling serde v1.0.175
[INFO] [stderr]    Compiling serde_json v1.0.103
[INFO] [stderr]    Compiling serde_derive v1.0.175
[INFO] [stderr]    Compiling unicode-segmentation v1.10.1
[INFO] [stderr]     Checking minigrep v0.1.0 (/opt/rustwide/workdir/17_minigrep)
[INFO] [stderr]     Checking iterators v0.1.0 (/opt/rustwide/workdir/19_iterators)
[INFO] [stderr]     Checking generics v0.1.0 (/opt/rustwide/workdir/13_generics)
[INFO] [stderr]     Checking strum v0.17.1
[INFO] [stderr]     Checking modules v0.1.0 (/opt/rustwide/workdir/09_modules)
[INFO] [stderr]     Checking writing_tests v0.1.0 (/opt/rustwide/workdir/16_writing_tests)
[INFO] [stderr]     Checking traits v0.1.0 (/opt/rustwide/workdir/14_traits)
[INFO] [stderr]     Checking slices v0.1.0 (/opt/rustwide/workdir/04_slices)
[INFO] [stderr]     Checking smart_pointers v0.1.0 (/opt/rustwide/workdir/20_smart_pointers)
[INFO] [stderr]     Checking getrandom v0.2.10
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]    Compiling quote v1.0.31
[INFO] [stdout] warning: struct `Shoe` is never constructed
[INFO] [stdout]  --> 19_iterators/src/lib.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Shoe {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `shoes_in_size` is never used
[INFO] [stdout]   --> 19_iterators/src/lib.rs:12:4
[INFO] [stdout]    |
[INFO] [stdout] 12 | fn shoes_in_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Rectangle` is never constructed
[INFO] [stdout]  --> 16_writing_tests/src/lib.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Rectangle {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `can_hold` is never used
[INFO] [stdout]   --> 16_writing_tests/src/lib.rs:11:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | impl Rectangle {
[INFO] [stdout]    | -------------- method in this implementation
[INFO] [stdout] 11 |     fn can_hold(self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> 20_smart_pointers/src/main.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons(i32, Box<List>),
[INFO] [stdout]   |     ---- ^^^  ^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons((), ()),
[INFO] [stdout]   |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `writing_tests` is imported redundantly
[INFO] [stdout]  --> 16_writing_tests/tests/integration_tests.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use writing_tests;
[INFO] [stdout]   |     ^^^^^^^^^^^^^ the item `writing_tests` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `value` is never read
[INFO] [stdout]  --> 16_writing_tests/tests/integration_tests.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Guess {
[INFO] [stdout]   |        ----- field in this struct
[INFO] [stdout] 6 |     value: i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `setup` is never used
[INFO] [stdout]  --> 16_writing_tests/tests/common/mod.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn setup() {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `generics` is imported redundantly
[INFO] [stdout]  --> 13_generics/src/main.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use generics::{self, Summary}; // this is the name of the module defined in Cargo.toml file
[INFO] [stdout]   |                ^^^^ the item `generics` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `modules` is imported redundantly
[INFO] [stdout]  --> 09_modules/src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use modules;
[INFO] [stdout]   |     ^^^^^^^ the item `modules` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking lifetimes v0.1.0 (/opt/rustwide/workdir/15_lifetimes)
[INFO] [stderr]     Checking closure v0.1.0 (/opt/rustwide/workdir/18_closure)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking error_handling v0.1.0 (/opt/rustwide/workdir/12_error_handling)
[INFO] [stderr]     Checking practice_concepts v0.1.0 (/opt/rustwide/workdir/05_control_flow)
[INFO] [stdout] warning: the item `generics` is imported redundantly
[INFO] [stdout]  --> 13_generics/src/main.rs:1:16
[INFO] [stdout]   |
[INFO] [stdout] 1 | use generics::{self, Summary}; // this is the name of the module defined in Cargo.toml file
[INFO] [stdout]   |                ^^^^ the item `generics` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stdout] warning: the item `modules` is imported redundantly
[INFO] [stdout]  --> 09_modules/src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use modules;
[INFO] [stdout]   |     ^^^^^^^ the item `modules` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking vectors v0.1.0 (/opt/rustwide/workdir/10_vectors)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking stack_heap v0.1.0 (/opt/rustwide/workdir/02_stack_heap)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]     Checking str_String v0.1.0 (/opt/rustwide/workdir/06_str_string)
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> 18_closure/src/main.rs:83:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     struct Rectangle {
[INFO] [stdout]    |            --------- field in this struct
[INFO] [stdout] 82 |         width: u32,
[INFO] [stdout] 83 |         height: u32,
[INFO] [stdout]    |         ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Rectangle` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking structure v0.1.0 (/opt/rustwide/workdir/07_structure)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]     Checking ownership v0.1.0 (/opt/rustwide/workdir/03_ownership)
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> 20_smart_pointers/src/main.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons(i32, Box<List>),
[INFO] [stdout]   |     ---- ^^^  ^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons((), ()),
[INFO] [stdout]   |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking guessing_game v0.1.0 (/opt/rustwide/workdir/01_guessing_game)
[INFO] [stderr]     Checking guessing_game2 v0.1.0 (/opt/rustwide/workdir/01a_guessing_game)
[INFO] [stderr]    Compiling strum_macros v0.17.1
[INFO] [stderr]     Checking enum_example v0.1.0 (/opt/rustwide/workdir/08_enum_example)
[INFO] [stdout] warning: variants `Cent` and `Dollar` are never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout] 7  | enum Coins {
[INFO] [stdout]    |      ----- variants in this enum
[INFO] [stdout] 8  |     Quarter(CANProvince),
[INFO] [stdout] 9  |     Cent,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 10 |     Dollar,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Coins` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv4Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:21:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | struct Ipv4Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv6Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct Ipv6Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `IPAddr` is never used
[INFO] [stdout]   --> 08_enum_example/src/main.rs:25:6
[INFO] [stdout]    |
[INFO] [stdout] 25 | enum IPAddr {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Cent` and `Dollar` are never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout] 7  | enum Coins {
[INFO] [stdout]    |      ----- variants in this enum
[INFO] [stdout] 8  |     Quarter(CANProvince),
[INFO] [stdout] 9  |     Cent,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 10 |     Dollar,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Coins` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv4Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:21:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | struct Ipv4Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Ipv6Addr` is never constructed
[INFO] [stdout]   --> 08_enum_example/src/main.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 | struct Ipv6Addr {}
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `IPAddr` is never used
[INFO] [stdout]   --> 08_enum_example/src/main.rs:25:6
[INFO] [stdout]    |
[INFO] [stdout] 25 | enum IPAddr {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking hash_map v0.1.0 (/opt/rustwide/workdir/11_hash_map)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 5.65s
[INFO] running `Command { std: "docker" "inspect" "6e96c378ea5f1eb5838c65f67d7129c686baa28b87830414998982c4ca1ea128", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6e96c378ea5f1eb5838c65f67d7129c686baa28b87830414998982c4ca1ea128", kill_on_drop: false }`
[INFO] [stdout] 6e96c378ea5f1eb5838c65f67d7129c686baa28b87830414998982c4ca1ea128