Dec 05 22:55:43.345 INFO testing gdemarcsek/learn-rust against try#6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468 for pr-56514
Dec 05 22:55:43.345 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56514/worker-6/try#6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-6/pr-56514/try#6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468:/source:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/source" "-e" "USER_ID=1000" "-e" "CMD=cargo +6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468-alt build --frozen" "-e" "CARGO_TARGET_DIR=/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/cargo-home" "-e" "RUSTUP_HOME=/rustup-home" "-m" "1536M" "--network" "none" "crater"`
Dec 05 22:55:43.843 INFO [stdout] 447441af995ee847563cf846dfb50adbbfc1027f92c6e3e9ae81f67e2da15618
Dec 05 22:55:43.845 INFO running `"docker" "start" "-a" "447441af995ee847563cf846dfb50adbbfc1027f92c6e3e9ae81f67e2da15618"`
Dec 05 22:55:45.944 INFO [stderr] usermod: no changes
Dec 05 22:55:46.016 INFO [stderr]    Compiling learn-rust v0.1.0 (/source)
Dec 05 22:55:46.408 INFO [stderr] warning: unused import: `std::*`
Dec 05 22:55:46.409 INFO [stderr]    --> src/main.rs:297:9
Dec 05 22:55:46.409 INFO [stderr]     |
Dec 05 22:55:46.409 INFO [stderr] 297 |     use std::*;         // glob import from Rust's standard library
Dec 05 22:55:46.410 INFO [stderr]     |         ^^^^^^
Dec 05 22:55:46.410 INFO [stderr]     |
Dec 05 22:55:46.410 INFO [stderr]     = note: #[warn(unused_imports)] on by default
Dec 05 22:55:46.410 INFO [stderr] 
Dec 05 22:55:46.484 INFO [stderr] warning: unreachable pattern
Dec 05 22:55:46.485 INFO [stderr]    --> src/main.rs:269:9
Dec 05 22:55:46.485 INFO [stderr]     |
Dec 05 22:55:46.486 INFO [stderr] 269 |         _ => -1,    // _ is a placeholder that matches any value - if we put it as last, this will mean what the "default" label menas for "switch" in C++
Dec 05 22:55:46.486 INFO [stderr]     |         ^
Dec 05 22:55:46.486 INFO [stderr]     |
Dec 05 22:55:46.487 INFO [stderr]     = note: #[warn(unreachable_patterns)] on by default
Dec 05 22:55:46.487 INFO [stderr] 
Dec 05 22:55:46.487 INFO [stderr] warning: unused variable: `x`
Dec 05 22:55:46.487 INFO [stderr]   --> src/main.rs:17:9
Dec 05 22:55:46.488 INFO [stderr]    |
Dec 05 22:55:46.488 INFO [stderr] 17 |     let x = 42;             // (type is inferred by the compiler whenever possible)
Dec 05 22:55:46.488 INFO [stderr]    |         ^ help: consider using `_x` instead
Dec 05 22:55:46.489 INFO [stderr]    |
Dec 05 22:55:46.489 INFO [stderr]    = note: #[warn(unused_variables)] on by default
Dec 05 22:55:46.489 INFO [stderr] 
Dec 05 22:55:46.489 INFO [stderr] warning: variable `x` is assigned to, but never used
Dec 05 22:55:46.489 INFO [stderr]   --> src/main.rs:19:13
Dec 05 22:55:46.490 INFO [stderr]    |
Dec 05 22:55:46.490 INFO [stderr] 19 |     let mut x = 42;         // Now 'x' is declared to be mutable, thus...
Dec 05 22:55:46.490 INFO [stderr]    |             ^
Dec 05 22:55:46.490 INFO [stderr]    |
Dec 05 22:55:46.491 INFO [stderr]    = note: consider using `_x` instead
Dec 05 22:55:46.491 INFO [stderr] 
Dec 05 22:55:46.491 INFO [stderr] warning: value assigned to `x` is never read
Dec 05 22:55:46.491 INFO [stderr]   --> src/main.rs:20:5
Dec 05 22:55:46.491 INFO [stderr]    |
Dec 05 22:55:46.492 INFO [stderr] 20 |     x = 21;                 // its value can be changed later on
Dec 05 22:55:46.492 INFO [stderr]    |     ^
Dec 05 22:55:46.492 INFO [stderr]    |
Dec 05 22:55:46.492 INFO [stderr]    = note: #[warn(unused_assignments)] on by default
Dec 05 22:55:46.493 INFO [stderr] 
Dec 05 22:55:46.493 INFO [stderr] warning: unused variable: `s`
Dec 05 22:55:46.493 INFO [stderr]   --> src/main.rs:40:13
Dec 05 22:55:46.493 INFO [stderr]    |
Dec 05 22:55:46.494 INFO [stderr] 40 |         let s = String::from("dynamically allocated string");           // s owns the allocated memory...
Dec 05 22:55:46.494 INFO [stderr]    |             ^ help: consider using `_s` instead
Dec 05 22:55:46.494 INFO [stderr] 
Dec 05 22:55:46.494 INFO [stderr] warning: unused variable: `y`
Dec 05 22:55:46.495 INFO [stderr]   --> src/main.rs:50:9
Dec 05 22:55:46.495 INFO [stderr]    |
Dec 05 22:55:46.495 INFO [stderr] 50 |     let y = x;          // a copy of the value of 'x'
Dec 05 22:55:46.495 INFO [stderr]    |         ^ help: consider using `_y` instead
Dec 05 22:55:46.495 INFO [stderr] 
Dec 05 22:55:46.495 INFO [stderr] warning: unused variable: `s4`
Dec 05 22:55:46.495 INFO [stderr]   --> src/main.rs:72:9
Dec 05 22:55:46.495 INFO [stderr]    |
Dec 05 22:55:46.495 INFO [stderr] 72 |     let s4 = gives_ownership();
Dec 05 22:55:46.495 INFO [stderr]    |         ^^ help: consider using `_s4` instead
Dec 05 22:55:46.495 INFO [stderr] 
Dec 05 22:55:46.495 INFO [stderr] warning: unused variable: `r1`
Dec 05 22:55:46.495 INFO [stderr]    --> src/main.rs:105:13
Dec 05 22:55:46.495 INFO [stderr]     |
Dec 05 22:55:46.495 INFO [stderr] 105 |         let r1 = &mut s1;
Dec 05 22:55:46.495 INFO [stderr]     |             ^^ help: consider using `_r1` instead
Dec 05 22:55:46.495 INFO [stderr] 
Dec 05 22:55:46.496 INFO [stderr] warning: unused variable: `r2`
Dec 05 22:55:46.496 INFO [stderr]    --> src/main.rs:110:9
Dec 05 22:55:46.496 INFO [stderr]     |
Dec 05 22:55:46.496 INFO [stderr] 110 |     let r2 = &s1;                   // but out of the scope of 'r1', we can create a reference again...
Dec 05 22:55:46.496 INFO [stderr]     |         ^^ help: consider using `_r2` instead
Dec 05 22:55:46.496 INFO [stderr] 
Dec 05 22:55:46.496 INFO [stderr] warning: unused variable: `r3`
Dec 05 22:55:46.496 INFO [stderr]    --> src/main.rs:111:9
Dec 05 22:55:46.496 INFO [stderr]     |
Dec 05 22:55:46.496 INFO [stderr] 111 |     let r3 = &s1;                   // ...even multiple immutable ones
Dec 05 22:55:46.496 INFO [stderr]     |         ^^ help: consider using `_r3` instead
Dec 05 22:55:46.496 INFO [stderr] 
Dec 05 22:55:46.496 INFO [stderr] warning: value assigned to `slice3` is never read
Dec 05 22:55:46.496 INFO [stderr]    --> src/main.rs:150:13
Dec 05 22:55:46.496 INFO [stderr]     |
Dec 05 22:55:46.496 INFO [stderr] 150 |     let mut slice3 = &s[1..6];
Dec 05 22:55:46.496 INFO [stderr]     |             ^^^^^^
Dec 05 22:55:46.496 INFO [stderr] 
Dec 05 22:55:46.496 INFO [stderr] warning: unused variable: `slice4`
Dec 05 22:55:46.496 INFO [stderr]    --> src/main.rs:155:9
Dec 05 22:55:46.496 INFO [stderr]     |
Dec 05 22:55:46.496 INFO [stderr] 155 |     let slice4: &[i32];         // the type of each item must be 'i32'
Dec 05 22:55:46.496 INFO [stderr]     |         ^^^^^^ help: consider using `_slice4` instead
Dec 05 22:55:46.496 INFO [stderr] 
Dec 05 22:55:46.496 INFO [stderr] warning: unused variable: `red`
Dec 05 22:55:46.496 INFO [stderr]    --> src/main.rs:191:9
Dec 05 22:55:46.496 INFO [stderr]     |
Dec 05 22:55:46.496 INFO [stderr] 191 |     let red = RGBColor(0xff, 0x00, 0x00);
Dec 05 22:55:46.496 INFO [stderr]     |         ^^^ help: consider using `_red` instead
Dec 05 22:55:46.496 INFO [stderr] 
Dec 05 22:55:46.497 INFO [stderr] warning: unused variable: `foreign`
Dec 05 22:55:46.497 INFO [stderr]    --> src/main.rs:233:9
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
Dec 05 22:55:46.497 INFO [stderr]     |         ^^^^^^^ help: consider using `_foreign` instead
Dec 05 22:55:46.497 INFO [stderr] 
Dec 05 22:55:46.497 INFO [stderr] warning: unused variable: `some_ip`
Dec 05 22:55:46.497 INFO [stderr]    --> src/main.rs:238:9
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr] 238 |     let some_ip = Some(home);
Dec 05 22:55:46.497 INFO [stderr]     |         ^^^^^^^ help: consider using `_some_ip` instead
Dec 05 22:55:46.497 INFO [stderr] 
Dec 05 22:55:46.497 INFO [stderr] warning: unused variable: `absent_ip`
Dec 05 22:55:46.497 INFO [stderr]    --> src/main.rs:240:9
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr] 240 |     let absent_ip: Option<IpAddress> = None; 
Dec 05 22:55:46.497 INFO [stderr]     |         ^^^^^^^^^ help: consider using `_absent_ip` instead
Dec 05 22:55:46.497 INFO [stderr] 
Dec 05 22:55:46.497 INFO [stderr] warning: unused variable: `x`
Dec 05 22:55:46.497 INFO [stderr]    --> src/main.rs:243:9
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr] 243 |     let x: i8 = 5;
Dec 05 22:55:46.497 INFO [stderr]     |         ^ help: consider using `_x` instead
Dec 05 22:55:46.497 INFO [stderr] 
Dec 05 22:55:46.497 INFO [stderr] warning: unused variable: `y`
Dec 05 22:55:46.497 INFO [stderr]    --> src/main.rs:244:9
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr] 244 |     let y: Option<i8> = Some(5);
Dec 05 22:55:46.497 INFO [stderr]     |         ^ help: consider using `_y` instead
Dec 05 22:55:46.497 INFO [stderr] 
Dec 05 22:55:46.497 INFO [stderr] warning: unused variable: `retcode`
Dec 05 22:55:46.497 INFO [stderr]    --> src/main.rs:259:9
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr] 259 |     let retcode = match error {     // match forces us to cover all possible cases
Dec 05 22:55:46.497 INFO [stderr]     |         ^^^^^^^ help: consider using `_retcode` instead
Dec 05 22:55:46.497 INFO [stderr] 
Dec 05 22:55:46.497 INFO [stderr] warning: variable does not need to be mutable
Dec 05 22:55:46.497 INFO [stderr]    --> src/main.rs:139:9
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr] 139 |     let mut s = String::from("hello world");
Dec 05 22:55:46.497 INFO [stderr]     |         ----^
Dec 05 22:55:46.497 INFO [stderr]     |         |
Dec 05 22:55:46.497 INFO [stderr]     |         help: remove this `mut`
Dec 05 22:55:46.497 INFO [stderr]     |
Dec 05 22:55:46.497 INFO [stderr]     = note: #[warn(unused_mut)] on by default
Dec 05 22:55:46.497 INFO [stderr] 
Dec 05 22:55:46.502 INFO [stderr] warning: variant is never constructed: `NetworkError`
Dec 05 22:55:46.502 INFO [stderr]    --> src/main.rs:252:9
Dec 05 22:55:46.502 INFO [stderr]     |
Dec 05 22:55:46.503 INFO [stderr] 252 |         NetworkError,
Dec 05 22:55:46.503 INFO [stderr]     |         ^^^^^^^^^^^^
Dec 05 22:55:46.503 INFO [stderr]     |
Dec 05 22:55:46.503 INFO [stderr]     = note: #[warn(dead_code)] on by default
Dec 05 22:55:46.503 INFO [stderr] 
Dec 05 22:55:46.504 INFO [stderr] warning: variant is never constructed: `SerilizationError`
Dec 05 22:55:46.504 INFO [stderr]    --> src/main.rs:253:9
Dec 05 22:55:46.504 INFO [stderr]     |
Dec 05 22:55:46.504 INFO [stderr] 253 |         SerilizationError(String),
Dec 05 22:55:46.505 INFO [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 05 22:55:46.505 INFO [stderr] 
Dec 05 22:55:46.505 INFO [stderr] warning: function is never used: `closures`
Dec 05 22:55:46.505 INFO [stderr]    --> src/main.rs:310:1
Dec 05 22:55:46.505 INFO [stderr]     |
Dec 05 22:55:46.506 INFO [stderr] 310 | fn closures() {
Dec 05 22:55:46.506 INFO [stderr]     | ^^^^^^^^^^^^^
Dec 05 22:55:46.506 INFO [stderr] 
Dec 05 22:55:46.506 INFO [stderr] warning: variable `className` should have a snake case name such as `class_name`
Dec 05 22:55:46.506 INFO [stderr]    --> src/main.rs:264:41
Dec 05 22:55:46.507 INFO [stderr]     |
Dec 05 22:55:46.507 INFO [stderr] 264 |         RPCCallError::SerilizationError(className) => {
Dec 05 22:55:46.507 INFO [stderr]     |                                         ^^^^^^^^^
Dec 05 22:55:46.507 INFO [stderr]     |
Dec 05 22:55:46.507 INFO [stderr]     = note: #[warn(non_snake_case)] on by default
Dec 05 22:55:46.508 INFO [stderr] 
Dec 05 22:55:47.006 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.03s
Dec 05 22:55:47.009 INFO [stderr] su: No module specific data is present
Dec 05 22:55:48.167 INFO running `"docker" "inspect" "447441af995ee847563cf846dfb50adbbfc1027f92c6e3e9ae81f67e2da15618"`
Dec 05 22:55:48.538 INFO running `"docker" "rm" "-f" "447441af995ee847563cf846dfb50adbbfc1027f92c6e3e9ae81f67e2da15618"`
Dec 05 22:55:48.894 INFO [stdout] 447441af995ee847563cf846dfb50adbbfc1027f92c6e3e9ae81f67e2da15618
Dec 05 22:55:48.900 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56514/worker-6/try#6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-6/pr-56514/try#6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468:/source:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/source" "-e" "USER_ID=1000" "-e" "CMD=cargo +6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468-alt test --frozen --no-run" "-e" "CARGO_TARGET_DIR=/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/cargo-home" "-e" "RUSTUP_HOME=/rustup-home" "-m" "1536M" "--network" "none" "crater"`
Dec 05 22:55:49.393 INFO [stdout] 5ef7311c9a0b3f1a387358b5384b11119e3774eb3e0a72080c6447ca57bd5edc
Dec 05 22:55:49.396 INFO running `"docker" "start" "-a" "5ef7311c9a0b3f1a387358b5384b11119e3774eb3e0a72080c6447ca57bd5edc"`
Dec 05 22:55:51.692 INFO [stderr] usermod: no changes
Dec 05 22:55:51.760 INFO [stderr]    Compiling learn-rust v0.1.0 (/source)
Dec 05 22:55:52.209 INFO [stderr] warning: unused import: `std::*`
Dec 05 22:55:52.209 INFO [stderr]    --> src/main.rs:297:9
Dec 05 22:55:52.209 INFO [stderr]     |
Dec 05 22:55:52.209 INFO [stderr] 297 |     use std::*;         // glob import from Rust's standard library
Dec 05 22:55:52.209 INFO [stderr]     |         ^^^^^^
Dec 05 22:55:52.209 INFO [stderr]     |
Dec 05 22:55:52.209 INFO [stderr]     = note: #[warn(unused_imports)] on by default
Dec 05 22:55:52.209 INFO [stderr] 
Dec 05 22:55:52.287 INFO [stderr] warning: unreachable pattern
Dec 05 22:55:52.287 INFO [stderr]    --> src/main.rs:269:9
Dec 05 22:55:52.287 INFO [stderr]     |
Dec 05 22:55:52.287 INFO [stderr] 269 |         _ => -1,    // _ is a placeholder that matches any value - if we put it as last, this will mean what the "default" label menas for "switch" in C++
Dec 05 22:55:52.287 INFO [stderr]     |         ^
Dec 05 22:55:52.287 INFO [stderr]     |
Dec 05 22:55:52.287 INFO [stderr]     = note: #[warn(unreachable_patterns)] on by default
Dec 05 22:55:52.287 INFO [stderr] 
Dec 05 22:55:52.287 INFO [stderr] warning: unused variable: `x`
Dec 05 22:55:52.287 INFO [stderr]   --> src/main.rs:17:9
Dec 05 22:55:52.287 INFO [stderr]    |
Dec 05 22:55:52.287 INFO [stderr] 17 |     let x = 42;             // (type is inferred by the compiler whenever possible)
Dec 05 22:55:52.287 INFO [stderr]    |         ^ help: consider using `_x` instead
Dec 05 22:55:52.287 INFO [stderr]    |
Dec 05 22:55:52.287 INFO [stderr]    = note: #[warn(unused_variables)] on by default
Dec 05 22:55:52.287 INFO [stderr] 
Dec 05 22:55:52.287 INFO [stderr] warning: variable `x` is assigned to, but never used
Dec 05 22:55:52.287 INFO [stderr]   --> src/main.rs:19:13
Dec 05 22:55:52.287 INFO [stderr]    |
Dec 05 22:55:52.287 INFO [stderr] 19 |     let mut x = 42;         // Now 'x' is declared to be mutable, thus...
Dec 05 22:55:52.287 INFO [stderr]    |             ^
Dec 05 22:55:52.287 INFO [stderr]    |
Dec 05 22:55:52.287 INFO [stderr]    = note: consider using `_x` instead
Dec 05 22:55:52.287 INFO [stderr] 
Dec 05 22:55:52.287 INFO [stderr] warning: value assigned to `x` is never read
Dec 05 22:55:52.287 INFO [stderr]   --> src/main.rs:20:5
Dec 05 22:55:52.287 INFO [stderr]    |
Dec 05 22:55:52.287 INFO [stderr] 20 |     x = 21;                 // its value can be changed later on
Dec 05 22:55:52.287 INFO [stderr]    |     ^
Dec 05 22:55:52.287 INFO [stderr]    |
Dec 05 22:55:52.287 INFO [stderr]    = note: #[warn(unused_assignments)] on by default
Dec 05 22:55:52.287 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `s`
Dec 05 22:55:52.288 INFO [stderr]   --> src/main.rs:40:13
Dec 05 22:55:52.288 INFO [stderr]    |
Dec 05 22:55:52.288 INFO [stderr] 40 |         let s = String::from("dynamically allocated string");           // s owns the allocated memory...
Dec 05 22:55:52.288 INFO [stderr]    |             ^ help: consider using `_s` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `y`
Dec 05 22:55:52.288 INFO [stderr]   --> src/main.rs:50:9
Dec 05 22:55:52.288 INFO [stderr]    |
Dec 05 22:55:52.288 INFO [stderr] 50 |     let y = x;          // a copy of the value of 'x'
Dec 05 22:55:52.288 INFO [stderr]    |         ^ help: consider using `_y` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `s4`
Dec 05 22:55:52.288 INFO [stderr]   --> src/main.rs:72:9
Dec 05 22:55:52.288 INFO [stderr]    |
Dec 05 22:55:52.288 INFO [stderr] 72 |     let s4 = gives_ownership();
Dec 05 22:55:52.288 INFO [stderr]    |         ^^ help: consider using `_s4` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `r1`
Dec 05 22:55:52.288 INFO [stderr]    --> src/main.rs:105:13
Dec 05 22:55:52.288 INFO [stderr]     |
Dec 05 22:55:52.288 INFO [stderr] 105 |         let r1 = &mut s1;
Dec 05 22:55:52.288 INFO [stderr]     |             ^^ help: consider using `_r1` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `r2`
Dec 05 22:55:52.288 INFO [stderr]    --> src/main.rs:110:9
Dec 05 22:55:52.288 INFO [stderr]     |
Dec 05 22:55:52.288 INFO [stderr] 110 |     let r2 = &s1;                   // but out of the scope of 'r1', we can create a reference again...
Dec 05 22:55:52.288 INFO [stderr]     |         ^^ help: consider using `_r2` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `r3`
Dec 05 22:55:52.288 INFO [stderr]    --> src/main.rs:111:9
Dec 05 22:55:52.288 INFO [stderr]     |
Dec 05 22:55:52.288 INFO [stderr] 111 |     let r3 = &s1;                   // ...even multiple immutable ones
Dec 05 22:55:52.288 INFO [stderr]     |         ^^ help: consider using `_r3` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: value assigned to `slice3` is never read
Dec 05 22:55:52.288 INFO [stderr]    --> src/main.rs:150:13
Dec 05 22:55:52.288 INFO [stderr]     |
Dec 05 22:55:52.288 INFO [stderr] 150 |     let mut slice3 = &s[1..6];
Dec 05 22:55:52.288 INFO [stderr]     |             ^^^^^^
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `slice4`
Dec 05 22:55:52.288 INFO [stderr]    --> src/main.rs:155:9
Dec 05 22:55:52.288 INFO [stderr]     |
Dec 05 22:55:52.288 INFO [stderr] 155 |     let slice4: &[i32];         // the type of each item must be 'i32'
Dec 05 22:55:52.288 INFO [stderr]     |         ^^^^^^ help: consider using `_slice4` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.288 INFO [stderr] warning: unused variable: `red`
Dec 05 22:55:52.288 INFO [stderr]    --> src/main.rs:191:9
Dec 05 22:55:52.288 INFO [stderr]     |
Dec 05 22:55:52.288 INFO [stderr] 191 |     let red = RGBColor(0xff, 0x00, 0x00);
Dec 05 22:55:52.288 INFO [stderr]     |         ^^^ help: consider using `_red` instead
Dec 05 22:55:52.288 INFO [stderr] 
Dec 05 22:55:52.289 INFO [stderr] warning: unused variable: `foreign`
Dec 05 22:55:52.289 INFO [stderr]    --> src/main.rs:233:9
Dec 05 22:55:52.289 INFO [stderr]     |
Dec 05 22:55:52.289 INFO [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
Dec 05 22:55:52.289 INFO [stderr]     |         ^^^^^^^ help: consider using `_foreign` instead
Dec 05 22:55:52.289 INFO [stderr] 
Dec 05 22:55:52.289 INFO [stderr] warning: unused variable: `some_ip`
Dec 05 22:55:52.289 INFO [stderr]    --> src/main.rs:238:9
Dec 05 22:55:52.289 INFO [stderr]     |
Dec 05 22:55:52.289 INFO [stderr] 238 |     let some_ip = Some(home);
Dec 05 22:55:52.289 INFO [stderr]     |         ^^^^^^^ help: consider using `_some_ip` instead
Dec 05 22:55:52.289 INFO [stderr] 
Dec 05 22:55:52.289 INFO [stderr] warning: unused variable: `absent_ip`
Dec 05 22:55:52.289 INFO [stderr]    --> src/main.rs:240:9
Dec 05 22:55:52.289 INFO [stderr]     |
Dec 05 22:55:52.289 INFO [stderr] 240 |     let absent_ip: Option<IpAddress> = None; 
Dec 05 22:55:52.289 INFO [stderr]     |         ^^^^^^^^^ help: consider using `_absent_ip` instead
Dec 05 22:55:52.289 INFO [stderr] 
Dec 05 22:55:52.289 INFO [stderr] warning: unused variable: `x`
Dec 05 22:55:52.289 INFO [stderr]    --> src/main.rs:243:9
Dec 05 22:55:52.289 INFO [stderr]     |
Dec 05 22:55:52.289 INFO [stderr] 243 |     let x: i8 = 5;
Dec 05 22:55:52.289 INFO [stderr]     |         ^ help: consider using `_x` instead
Dec 05 22:55:52.289 INFO [stderr] 
Dec 05 22:55:52.289 INFO [stderr] warning: unused variable: `y`
Dec 05 22:55:52.289 INFO [stderr]    --> src/main.rs:244:9
Dec 05 22:55:52.289 INFO [stderr]     |
Dec 05 22:55:52.289 INFO [stderr] 244 |     let y: Option<i8> = Some(5);
Dec 05 22:55:52.289 INFO [stderr]     |         ^ help: consider using `_y` instead
Dec 05 22:55:52.289 INFO [stderr] 
Dec 05 22:55:52.289 INFO [stderr] warning: unused variable: `retcode`
Dec 05 22:55:52.289 INFO [stderr]    --> src/main.rs:259:9
Dec 05 22:55:52.289 INFO [stderr]     |
Dec 05 22:55:52.289 INFO [stderr] 259 |     let retcode = match error {     // match forces us to cover all possible cases
Dec 05 22:55:52.289 INFO [stderr]     |         ^^^^^^^ help: consider using `_retcode` instead
Dec 05 22:55:52.289 INFO [stderr] 
Dec 05 22:55:52.298 INFO [stderr] warning: variable does not need to be mutable
Dec 05 22:55:52.298 INFO [stderr]    --> src/main.rs:139:9
Dec 05 22:55:52.298 INFO [stderr]     |
Dec 05 22:55:52.298 INFO [stderr] 139 |     let mut s = String::from("hello world");
Dec 05 22:55:52.298 INFO [stderr]     |         ----^
Dec 05 22:55:52.298 INFO [stderr]     |         |
Dec 05 22:55:52.298 INFO [stderr]     |         help: remove this `mut`
Dec 05 22:55:52.298 INFO [stderr]     |
Dec 05 22:55:52.298 INFO [stderr]     = note: #[warn(unused_mut)] on by default
Dec 05 22:55:52.299 INFO [stderr] 
Dec 05 22:55:52.305 INFO [stderr] warning: variant is never constructed: `NetworkError`
Dec 05 22:55:52.305 INFO [stderr]    --> src/main.rs:252:9
Dec 05 22:55:52.305 INFO [stderr]     |
Dec 05 22:55:52.305 INFO [stderr] 252 |         NetworkError,
Dec 05 22:55:52.305 INFO [stderr]     |         ^^^^^^^^^^^^
Dec 05 22:55:52.305 INFO [stderr]     |
Dec 05 22:55:52.305 INFO [stderr]     = note: #[warn(dead_code)] on by default
Dec 05 22:55:52.306 INFO [stderr] 
Dec 05 22:55:52.306 INFO [stderr] warning: variant is never constructed: `SerilizationError`
Dec 05 22:55:52.306 INFO [stderr]    --> src/main.rs:253:9
Dec 05 22:55:52.306 INFO [stderr]     |
Dec 05 22:55:52.306 INFO [stderr] 253 |         SerilizationError(String),
Dec 05 22:55:52.306 INFO [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 05 22:55:52.306 INFO [stderr] 
Dec 05 22:55:52.306 INFO [stderr] warning: function is never used: `closures`
Dec 05 22:55:52.306 INFO [stderr]    --> src/main.rs:310:1
Dec 05 22:55:52.306 INFO [stderr]     |
Dec 05 22:55:52.306 INFO [stderr] 310 | fn closures() {
Dec 05 22:55:52.306 INFO [stderr]     | ^^^^^^^^^^^^^
Dec 05 22:55:52.306 INFO [stderr] 
Dec 05 22:55:52.306 INFO [stderr] warning: variable `className` should have a snake case name such as `class_name`
Dec 05 22:55:52.307 INFO [stderr]    --> src/main.rs:264:41
Dec 05 22:55:52.307 INFO [stderr]     |
Dec 05 22:55:52.307 INFO [stderr] 264 |         RPCCallError::SerilizationError(className) => {
Dec 05 22:55:52.307 INFO [stderr]     |                                         ^^^^^^^^^
Dec 05 22:55:52.307 INFO [stderr]     |
Dec 05 22:55:52.307 INFO [stderr]     = note: #[warn(non_snake_case)] on by default
Dec 05 22:55:52.307 INFO [stderr] 
Dec 05 22:55:52.705 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.98s
Dec 05 22:55:52.708 INFO [stderr] su: No module specific data is present
Dec 05 22:55:53.440 INFO running `"docker" "inspect" "5ef7311c9a0b3f1a387358b5384b11119e3774eb3e0a72080c6447ca57bd5edc"`
Dec 05 22:55:53.742 INFO running `"docker" "rm" "-f" "5ef7311c9a0b3f1a387358b5384b11119e3774eb3e0a72080c6447ca57bd5edc"`
Dec 05 22:55:54.086 INFO [stdout] 5ef7311c9a0b3f1a387358b5384b11119e3774eb3e0a72080c6447ca57bd5edc
Dec 05 22:55:54.092 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56514/worker-6/try#6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-6/pr-56514/try#6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468:/source:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/source" "-e" "USER_ID=1000" "-e" "CMD=cargo +6eb0fd3ac58f9b16bddb9924a17c3b6c156aa468-alt test --frozen" "-e" "CARGO_TARGET_DIR=/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/cargo-home" "-e" "RUSTUP_HOME=/rustup-home" "-m" "1536M" "--network" "none" "crater"`
Dec 05 22:55:54.590 INFO [stdout] 0894131e7c22ce598f53606e0ae02cc4dc964c4cc5e268a714366ac451e989f4
Dec 05 22:55:54.592 INFO running `"docker" "start" "-a" "0894131e7c22ce598f53606e0ae02cc4dc964c4cc5e268a714366ac451e989f4"`
Dec 05 22:55:56.636 INFO [stderr] usermod: no changes
Dec 05 22:55:56.720 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.03s
Dec 05 22:55:56.720 INFO [stderr]      Running /target/debug/deps/learn_rust-85b1899c12d087f5
Dec 05 22:55:56.728 INFO [stdout] 
Dec 05 22:55:56.728 INFO [stdout] running 0 tests
Dec 05 22:55:56.728 INFO [stdout] 
Dec 05 22:55:56.728 INFO [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
Dec 05 22:55:56.728 INFO [stdout] 
Dec 05 22:55:56.729 INFO [stderr] su: No module specific data is present
Dec 05 22:55:58.026 INFO running `"docker" "inspect" "0894131e7c22ce598f53606e0ae02cc4dc964c4cc5e268a714366ac451e989f4"`
Dec 05 22:55:58.430 INFO running `"docker" "rm" "-f" "0894131e7c22ce598f53606e0ae02cc4dc964c4cc5e268a714366ac451e989f4"`
Dec 05 22:55:58.804 INFO [stdout] 0894131e7c22ce598f53606e0ae02cc4dc964c4cc5e268a714366ac451e989f4