[INFO] updating cached repository tperdue321/rust_basics
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/tperdue321/rust_basics
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/tperdue321/rust_basics" "work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/tperdue321/rust_basics"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/tperdue321/rust_basics'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/tperdue321/rust_basics" "work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/tperdue321/rust_basics"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/tperdue321/rust_basics'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 54afaa614ea2aedeb79508968f5e08a147b12e2e
[INFO] sha for GitHub repo tperdue321/rust_basics: 54afaa614ea2aedeb79508968f5e08a147b12e2e
[INFO] validating manifest of tperdue321/rust_basics on toolchain master#60960a260f7b5c695fd0717311d72ce62dd4eb43
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of tperdue321/rust_basics on toolchain try#266783e4e09e4e9d5307c1c8e695659c58bbcac7
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing tperdue321/rust_basics
[INFO] finished frobbing tperdue321/rust_basics
[INFO] frobbed toml for tperdue321/rust_basics written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/tperdue321/rust_basics/Cargo.toml
[INFO] started frobbing tperdue321/rust_basics
[INFO] finished frobbing tperdue321/rust_basics
[INFO] frobbed toml for tperdue321/rust_basics written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/tperdue321/rust_basics/Cargo.toml
[INFO] crate tperdue321/rust_basics already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking tperdue321/rust_basics against master#60960a260f7b5c695fd0717311d72ce62dd4eb43 for pr-63376
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63376/worker-2/master#60960a260f7b5c695fd0717311d72ce62dd4eb43:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/tperdue321/rust_basics:/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=forbid" "-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" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] e29c60fa4ef12a0ef9a0e09a4b2a8ad5bb31cad3ef039b28e69b9081414b3eff
[INFO] running `"docker" "start" "-a" "e29c60fa4ef12a0ef9a0e09a4b2a8ad5bb31cad3ef039b28e69b9081414b3eff"`
[INFO] [stderr]     Checking basics v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]  --> src/main.rs:9:9
[INFO] [stderr]   |
[INFO] [stderr] 9 |     let a: i32 = 1;
[INFO] [stderr]   |         ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable `b` is assigned to, but never used
[INFO] [stderr]   --> src/main.rs:14:13
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let mut b: i32 = 15;
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: consider using `_b` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `b` is never read
[INFO] [stderr]   --> src/main.rs:15:5
[INFO] [stderr]    |
[INFO] [stderr] 15 |     b = 25;
[INFO] [stderr]    |     ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let x: i32; // bindings need to be given a starting val. this is bad
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `x` is never read
[INFO] [stderr]   --> src/main.rs:38:13
[INFO] [stderr]    |
[INFO] [stderr] 38 |     let mut x: i32 = 1;
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:42:9
[INFO] [stderr]    |
[INFO] [stderr] 42 |     let y = 4;
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:45:9
[INFO] [stderr]    |
[INFO] [stderr] 45 |     let y = "I can also be bound to text!"; // `y` is now of a different type.
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:60:9
[INFO] [stderr]    |
[INFO] [stderr] 60 |     let x = return_int_plus_1(1);
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `diverges`
[INFO] [stderr]   --> src/main.rs:93:1
[INFO] [stderr]    |
[INFO] [stderr] 93 | fn diverges() -> ! {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]  --> src/main.rs:9:9
[INFO] [stderr]   |
[INFO] [stderr] 9 |     let a: i32 = 1;
[INFO] [stderr]   |         ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable `b` is assigned to, but never used
[INFO] [stderr]   --> src/main.rs:14:13
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let mut b: i32 = 15;
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: consider using `_b` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `b` is never read
[INFO] [stderr]   --> src/main.rs:15:5
[INFO] [stderr]    |
[INFO] [stderr] 15 |     b = 25;
[INFO] [stderr]    |     ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let x: i32; // bindings need to be given a starting val. this is bad
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `x` is never read
[INFO] [stderr]   --> src/main.rs:38:13
[INFO] [stderr]    |
[INFO] [stderr] 38 |     let mut x: i32 = 1;
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:42:9
[INFO] [stderr]    |
[INFO] [stderr] 42 |     let y = 4;
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:45:9
[INFO] [stderr]    |
[INFO] [stderr] 45 |     let y = "I can also be bound to text!"; // `y` is now of a different type.
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:60:9
[INFO] [stderr]    |
[INFO] [stderr] 60 |     let x = return_int_plus_1(1);
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `diverges`
[INFO] [stderr]   --> src/main.rs:93:1
[INFO] [stderr]    |
[INFO] [stderr] 93 | fn diverges() -> ! {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.54s
[INFO] running `"docker" "inspect" "e29c60fa4ef12a0ef9a0e09a4b2a8ad5bb31cad3ef039b28e69b9081414b3eff"`
[INFO] running `"docker" "rm" "-f" "e29c60fa4ef12a0ef9a0e09a4b2a8ad5bb31cad3ef039b28e69b9081414b3eff"`
[INFO] [stdout] e29c60fa4ef12a0ef9a0e09a4b2a8ad5bb31cad3ef039b28e69b9081414b3eff