Dec 13 18:41:11.356 INFO testing gdemarcsek/learn-rust against try#aa49d8ef14939ddec0e34b346b60174a5673d48f for pr-56550
Dec 13 18:41:11.356 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56550/worker-1/try#aa49d8ef14939ddec0e34b346b60174a5673d48f:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-1/pr-56550/try#aa49d8ef14939ddec0e34b346b60174a5673d48f:/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 +aa49d8ef14939ddec0e34b346b60174a5673d48f-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 13 18:41:11.980 INFO [stdout] e5794e695d46897f2a59825a85ab2cbcb0ee04c09995aa8e03741a510797a99c
Dec 13 18:41:11.991 INFO running `"docker" "start" "-a" "e5794e695d46897f2a59825a85ab2cbcb0ee04c09995aa8e03741a510797a99c"`
Dec 13 18:41:14.319 INFO [stderr] usermod: no changes
Dec 13 18:41:14.372 INFO [stderr]    Compiling learn-rust v0.1.0 (/source)
Dec 13 18:41:14.770 INFO [stderr] warning: unused import: `std::*`
Dec 13 18:41:14.770 INFO [stderr]    --> src/main.rs:297:9
Dec 13 18:41:14.770 INFO [stderr]     |
Dec 13 18:41:14.770 INFO [stderr] 297 |     use std::*;         // glob import from Rust's standard library
Dec 13 18:41:14.770 INFO [stderr]     |         ^^^^^^
Dec 13 18:41:14.770 INFO [stderr]     |
Dec 13 18:41:14.770 INFO [stderr]     = note: #[warn(unused_imports)] on by default
Dec 13 18:41:14.770 INFO [stderr] 
Dec 13 18:41:14.847 INFO [stderr] warning: unreachable pattern
Dec 13 18:41:14.847 INFO [stderr]    --> src/main.rs:269:9
Dec 13 18:41:14.847 INFO [stderr]     |
Dec 13 18:41:14.847 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 13 18:41:14.847 INFO [stderr]     |         ^
Dec 13 18:41:14.847 INFO [stderr]     |
Dec 13 18:41:14.847 INFO [stderr]     = note: #[warn(unreachable_patterns)] on by default
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `x`
Dec 13 18:41:14.848 INFO [stderr]   --> src/main.rs:17:9
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr] 17 |     let x = 42;             // (type is inferred by the compiler whenever possible)
Dec 13 18:41:14.848 INFO [stderr]    |         ^ help: consider using `_x` instead
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr]    = note: #[warn(unused_variables)] on by default
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: variable `x` is assigned to, but never used
Dec 13 18:41:14.848 INFO [stderr]   --> src/main.rs:19:13
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr] 19 |     let mut x = 42;         // Now 'x' is declared to be mutable, thus...
Dec 13 18:41:14.848 INFO [stderr]    |             ^
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr]    = note: consider using `_x` instead
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: value assigned to `x` is never read
Dec 13 18:41:14.848 INFO [stderr]   --> src/main.rs:20:5
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr] 20 |     x = 21;                 // its value can be changed later on
Dec 13 18:41:14.848 INFO [stderr]    |     ^
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr]    = note: #[warn(unused_assignments)] on by default
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `s`
Dec 13 18:41:14.848 INFO [stderr]   --> src/main.rs:40:13
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr] 40 |         let s = String::from("dynamically allocated string");           // s owns the allocated memory...
Dec 13 18:41:14.848 INFO [stderr]    |             ^ help: consider using `_s` instead
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `y`
Dec 13 18:41:14.848 INFO [stderr]   --> src/main.rs:50:9
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr] 50 |     let y = x;          // a copy of the value of 'x'
Dec 13 18:41:14.848 INFO [stderr]    |         ^ help: consider using `_y` instead
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `s4`
Dec 13 18:41:14.848 INFO [stderr]   --> src/main.rs:72:9
Dec 13 18:41:14.848 INFO [stderr]    |
Dec 13 18:41:14.848 INFO [stderr] 72 |     let s4 = gives_ownership();
Dec 13 18:41:14.848 INFO [stderr]    |         ^^ help: consider using `_s4` instead
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `r1`
Dec 13 18:41:14.848 INFO [stderr]    --> src/main.rs:105:13
Dec 13 18:41:14.848 INFO [stderr]     |
Dec 13 18:41:14.848 INFO [stderr] 105 |         let r1 = &mut s1;
Dec 13 18:41:14.848 INFO [stderr]     |             ^^ help: consider using `_r1` instead
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `r2`
Dec 13 18:41:14.848 INFO [stderr]    --> src/main.rs:110:9
Dec 13 18:41:14.848 INFO [stderr]     |
Dec 13 18:41:14.848 INFO [stderr] 110 |     let r2 = &s1;                   // but out of the scope of 'r1', we can create a reference again...
Dec 13 18:41:14.848 INFO [stderr]     |         ^^ help: consider using `_r2` instead
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `r3`
Dec 13 18:41:14.848 INFO [stderr]    --> src/main.rs:111:9
Dec 13 18:41:14.848 INFO [stderr]     |
Dec 13 18:41:14.848 INFO [stderr] 111 |     let r3 = &s1;                   // ...even multiple immutable ones
Dec 13 18:41:14.848 INFO [stderr]     |         ^^ help: consider using `_r3` instead
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: value assigned to `slice3` is never read
Dec 13 18:41:14.848 INFO [stderr]    --> src/main.rs:150:13
Dec 13 18:41:14.848 INFO [stderr]     |
Dec 13 18:41:14.848 INFO [stderr] 150 |     let mut slice3 = &s[1..6];
Dec 13 18:41:14.848 INFO [stderr]     |             ^^^^^^
Dec 13 18:41:14.848 INFO [stderr] 
Dec 13 18:41:14.848 INFO [stderr] warning: unused variable: `slice4`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:155:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 155 |     let slice4: &[i32];         // the type of each item must be 'i32'
Dec 13 18:41:14.849 INFO [stderr]     |         ^^^^^^ help: consider using `_slice4` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.849 INFO [stderr] warning: unused variable: `red`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:191:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 191 |     let red = RGBColor(0xff, 0x00, 0x00);
Dec 13 18:41:14.849 INFO [stderr]     |         ^^^ help: consider using `_red` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.849 INFO [stderr] warning: unused variable: `foreign`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:233:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
Dec 13 18:41:14.849 INFO [stderr]     |         ^^^^^^^ help: consider using `_foreign` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.849 INFO [stderr] warning: unused variable: `some_ip`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:238:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 238 |     let some_ip = Some(home);
Dec 13 18:41:14.849 INFO [stderr]     |         ^^^^^^^ help: consider using `_some_ip` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.849 INFO [stderr] warning: unused variable: `absent_ip`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:240:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 240 |     let absent_ip: Option<IpAddress> = None; 
Dec 13 18:41:14.849 INFO [stderr]     |         ^^^^^^^^^ help: consider using `_absent_ip` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.849 INFO [stderr] warning: unused variable: `x`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:243:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 243 |     let x: i8 = 5;
Dec 13 18:41:14.849 INFO [stderr]     |         ^ help: consider using `_x` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.849 INFO [stderr] warning: unused variable: `y`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:244:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 244 |     let y: Option<i8> = Some(5);
Dec 13 18:41:14.849 INFO [stderr]     |         ^ help: consider using `_y` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.849 INFO [stderr] warning: unused variable: `retcode`
Dec 13 18:41:14.849 INFO [stderr]    --> src/main.rs:259:9
Dec 13 18:41:14.849 INFO [stderr]     |
Dec 13 18:41:14.849 INFO [stderr] 259 |     let retcode = match error {     // match forces us to cover all possible cases
Dec 13 18:41:14.849 INFO [stderr]     |         ^^^^^^^ help: consider using `_retcode` instead
Dec 13 18:41:14.849 INFO [stderr] 
Dec 13 18:41:14.859 INFO [stderr] warning: variable does not need to be mutable
Dec 13 18:41:14.859 INFO [stderr]    --> src/main.rs:139:9
Dec 13 18:41:14.859 INFO [stderr]     |
Dec 13 18:41:14.859 INFO [stderr] 139 |     let mut s = String::from("hello world");
Dec 13 18:41:14.859 INFO [stderr]     |         ----^
Dec 13 18:41:14.859 INFO [stderr]     |         |
Dec 13 18:41:14.859 INFO [stderr]     |         help: remove this `mut`
Dec 13 18:41:14.859 INFO [stderr]     |
Dec 13 18:41:14.859 INFO [stderr]     = note: #[warn(unused_mut)] on by default
Dec 13 18:41:14.859 INFO [stderr] 
Dec 13 18:41:14.866 INFO [stderr] warning: variant is never constructed: `NetworkError`
Dec 13 18:41:14.866 INFO [stderr]    --> src/main.rs:252:9
Dec 13 18:41:14.866 INFO [stderr]     |
Dec 13 18:41:14.866 INFO [stderr] 252 |         NetworkError,
Dec 13 18:41:14.866 INFO [stderr]     |         ^^^^^^^^^^^^
Dec 13 18:41:14.866 INFO [stderr]     |
Dec 13 18:41:14.866 INFO [stderr]     = note: #[warn(dead_code)] on by default
Dec 13 18:41:14.866 INFO [stderr] 
Dec 13 18:41:14.866 INFO [stderr] warning: variant is never constructed: `SerilizationError`
Dec 13 18:41:14.866 INFO [stderr]    --> src/main.rs:253:9
Dec 13 18:41:14.866 INFO [stderr]     |
Dec 13 18:41:14.866 INFO [stderr] 253 |         SerilizationError(String),
Dec 13 18:41:14.866 INFO [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 13 18:41:14.866 INFO [stderr] 
Dec 13 18:41:14.866 INFO [stderr] warning: function is never used: `closures`
Dec 13 18:41:14.866 INFO [stderr]    --> src/main.rs:310:1
Dec 13 18:41:14.866 INFO [stderr]     |
Dec 13 18:41:14.866 INFO [stderr] 310 | fn closures() {
Dec 13 18:41:14.866 INFO [stderr]     | ^^^^^^^^^^^^^
Dec 13 18:41:14.866 INFO [stderr] 
Dec 13 18:41:14.867 INFO [stderr] warning: variable `className` should have a snake case name such as `class_name`
Dec 13 18:41:14.867 INFO [stderr]    --> src/main.rs:264:41
Dec 13 18:41:14.867 INFO [stderr]     |
Dec 13 18:41:14.867 INFO [stderr] 264 |         RPCCallError::SerilizationError(className) => {
Dec 13 18:41:14.867 INFO [stderr]     |                                         ^^^^^^^^^
Dec 13 18:41:14.867 INFO [stderr]     |
Dec 13 18:41:14.867 INFO [stderr]     = note: #[warn(non_snake_case)] on by default
Dec 13 18:41:14.867 INFO [stderr] 
Dec 13 18:41:15.458 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.12s
Dec 13 18:41:15.481 INFO [stderr] su: No module specific data is present
Dec 13 18:41:16.729 INFO running `"docker" "inspect" "e5794e695d46897f2a59825a85ab2cbcb0ee04c09995aa8e03741a510797a99c"`
Dec 13 18:41:17.111 INFO running `"docker" "rm" "-f" "e5794e695d46897f2a59825a85ab2cbcb0ee04c09995aa8e03741a510797a99c"`
Dec 13 18:41:17.523 INFO [stdout] e5794e695d46897f2a59825a85ab2cbcb0ee04c09995aa8e03741a510797a99c
Dec 13 18:41:17.531 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56550/worker-1/try#aa49d8ef14939ddec0e34b346b60174a5673d48f:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-1/pr-56550/try#aa49d8ef14939ddec0e34b346b60174a5673d48f:/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 +aa49d8ef14939ddec0e34b346b60174a5673d48f-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 13 18:41:18.115 INFO [stdout] 1292d38cacae3dcfe167ae7f2072deec7b0d39394686e6472eb73b8502788b31
Dec 13 18:41:18.120 INFO running `"docker" "start" "-a" "1292d38cacae3dcfe167ae7f2072deec7b0d39394686e6472eb73b8502788b31"`
Dec 13 18:41:19.510 INFO [stderr] usermod: no changes
Dec 13 18:41:19.574 INFO [stderr]    Compiling learn-rust v0.1.0 (/source)
Dec 13 18:41:20.047 INFO [stderr] warning: unused import: `std::*`
Dec 13 18:41:20.047 INFO [stderr]    --> src/main.rs:297:9
Dec 13 18:41:20.047 INFO [stderr]     |
Dec 13 18:41:20.047 INFO [stderr] 297 |     use std::*;         // glob import from Rust's standard library
Dec 13 18:41:20.047 INFO [stderr]     |         ^^^^^^
Dec 13 18:41:20.047 INFO [stderr]     |
Dec 13 18:41:20.047 INFO [stderr]     = note: #[warn(unused_imports)] on by default
Dec 13 18:41:20.047 INFO [stderr] 
Dec 13 18:41:20.119 INFO [stderr] warning: unreachable pattern
Dec 13 18:41:20.119 INFO [stderr]    --> src/main.rs:269:9
Dec 13 18:41:20.119 INFO [stderr]     |
Dec 13 18:41:20.119 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 13 18:41:20.119 INFO [stderr]     |         ^
Dec 13 18:41:20.119 INFO [stderr]     |
Dec 13 18:41:20.119 INFO [stderr]     = note: #[warn(unreachable_patterns)] on by default
Dec 13 18:41:20.119 INFO [stderr] 
Dec 13 18:41:20.119 INFO [stderr] warning: unused variable: `x`
Dec 13 18:41:20.119 INFO [stderr]   --> src/main.rs:17:9
Dec 13 18:41:20.119 INFO [stderr]    |
Dec 13 18:41:20.119 INFO [stderr] 17 |     let x = 42;             // (type is inferred by the compiler whenever possible)
Dec 13 18:41:20.119 INFO [stderr]    |         ^ help: consider using `_x` instead
Dec 13 18:41:20.119 INFO [stderr]    |
Dec 13 18:41:20.119 INFO [stderr]    = note: #[warn(unused_variables)] on by default
Dec 13 18:41:20.119 INFO [stderr] 
Dec 13 18:41:20.119 INFO [stderr] warning: variable `x` is assigned to, but never used
Dec 13 18:41:20.119 INFO [stderr]   --> src/main.rs:19:13
Dec 13 18:41:20.119 INFO [stderr]    |
Dec 13 18:41:20.119 INFO [stderr] 19 |     let mut x = 42;         // Now 'x' is declared to be mutable, thus...
Dec 13 18:41:20.119 INFO [stderr]    |             ^
Dec 13 18:41:20.119 INFO [stderr]    |
Dec 13 18:41:20.119 INFO [stderr]    = note: consider using `_x` instead
Dec 13 18:41:20.119 INFO [stderr] 
Dec 13 18:41:20.119 INFO [stderr] warning: value assigned to `x` is never read
Dec 13 18:41:20.119 INFO [stderr]   --> src/main.rs:20:5
Dec 13 18:41:20.119 INFO [stderr]    |
Dec 13 18:41:20.119 INFO [stderr] 20 |     x = 21;                 // its value can be changed later on
Dec 13 18:41:20.119 INFO [stderr]    |     ^
Dec 13 18:41:20.119 INFO [stderr]    |
Dec 13 18:41:20.119 INFO [stderr]    = note: #[warn(unused_assignments)] on by default
Dec 13 18:41:20.119 INFO [stderr] 
Dec 13 18:41:20.119 INFO [stderr] warning: unused variable: `s`
Dec 13 18:41:20.119 INFO [stderr]   --> src/main.rs:40:13
Dec 13 18:41:20.119 INFO [stderr]    |
Dec 13 18:41:20.119 INFO [stderr] 40 |         let s = String::from("dynamically allocated string");           // s owns the allocated memory...
Dec 13 18:41:20.120 INFO [stderr]    |             ^ help: consider using `_s` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `y`
Dec 13 18:41:20.120 INFO [stderr]   --> src/main.rs:50:9
Dec 13 18:41:20.120 INFO [stderr]    |
Dec 13 18:41:20.120 INFO [stderr] 50 |     let y = x;          // a copy of the value of 'x'
Dec 13 18:41:20.120 INFO [stderr]    |         ^ help: consider using `_y` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `s4`
Dec 13 18:41:20.120 INFO [stderr]   --> src/main.rs:72:9
Dec 13 18:41:20.120 INFO [stderr]    |
Dec 13 18:41:20.120 INFO [stderr] 72 |     let s4 = gives_ownership();
Dec 13 18:41:20.120 INFO [stderr]    |         ^^ help: consider using `_s4` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `r1`
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:105:13
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 105 |         let r1 = &mut s1;
Dec 13 18:41:20.120 INFO [stderr]     |             ^^ help: consider using `_r1` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `r2`
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:110:9
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 110 |     let r2 = &s1;                   // but out of the scope of 'r1', we can create a reference again...
Dec 13 18:41:20.120 INFO [stderr]     |         ^^ help: consider using `_r2` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `r3`
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:111:9
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 111 |     let r3 = &s1;                   // ...even multiple immutable ones
Dec 13 18:41:20.120 INFO [stderr]     |         ^^ help: consider using `_r3` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: value assigned to `slice3` is never read
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:150:13
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 150 |     let mut slice3 = &s[1..6];
Dec 13 18:41:20.120 INFO [stderr]     |             ^^^^^^
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `slice4`
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:155:9
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 155 |     let slice4: &[i32];         // the type of each item must be 'i32'
Dec 13 18:41:20.120 INFO [stderr]     |         ^^^^^^ help: consider using `_slice4` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `red`
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:191:9
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 191 |     let red = RGBColor(0xff, 0x00, 0x00);
Dec 13 18:41:20.120 INFO [stderr]     |         ^^^ help: consider using `_red` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `foreign`
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:233:9
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
Dec 13 18:41:20.120 INFO [stderr]     |         ^^^^^^^ help: consider using `_foreign` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.120 INFO [stderr] warning: unused variable: `some_ip`
Dec 13 18:41:20.120 INFO [stderr]    --> src/main.rs:238:9
Dec 13 18:41:20.120 INFO [stderr]     |
Dec 13 18:41:20.120 INFO [stderr] 238 |     let some_ip = Some(home);
Dec 13 18:41:20.120 INFO [stderr]     |         ^^^^^^^ help: consider using `_some_ip` instead
Dec 13 18:41:20.120 INFO [stderr] 
Dec 13 18:41:20.121 INFO [stderr] warning: unused variable: `absent_ip`
Dec 13 18:41:20.121 INFO [stderr]    --> src/main.rs:240:9
Dec 13 18:41:20.121 INFO [stderr]     |
Dec 13 18:41:20.121 INFO [stderr] 240 |     let absent_ip: Option<IpAddress> = None; 
Dec 13 18:41:20.121 INFO [stderr]     |         ^^^^^^^^^ help: consider using `_absent_ip` instead
Dec 13 18:41:20.121 INFO [stderr] 
Dec 13 18:41:20.121 INFO [stderr] warning: unused variable: `x`
Dec 13 18:41:20.121 INFO [stderr]    --> src/main.rs:243:9
Dec 13 18:41:20.121 INFO [stderr]     |
Dec 13 18:41:20.121 INFO [stderr] 243 |     let x: i8 = 5;
Dec 13 18:41:20.121 INFO [stderr]     |         ^ help: consider using `_x` instead
Dec 13 18:41:20.121 INFO [stderr] 
Dec 13 18:41:20.121 INFO [stderr] warning: unused variable: `y`
Dec 13 18:41:20.121 INFO [stderr]    --> src/main.rs:244:9
Dec 13 18:41:20.121 INFO [stderr]     |
Dec 13 18:41:20.121 INFO [stderr] 244 |     let y: Option<i8> = Some(5);
Dec 13 18:41:20.121 INFO [stderr]     |         ^ help: consider using `_y` instead
Dec 13 18:41:20.121 INFO [stderr] 
Dec 13 18:41:20.121 INFO [stderr] warning: unused variable: `retcode`
Dec 13 18:41:20.121 INFO [stderr]    --> src/main.rs:259:9
Dec 13 18:41:20.121 INFO [stderr]     |
Dec 13 18:41:20.121 INFO [stderr] 259 |     let retcode = match error {     // match forces us to cover all possible cases
Dec 13 18:41:20.121 INFO [stderr]     |         ^^^^^^^ help: consider using `_retcode` instead
Dec 13 18:41:20.121 INFO [stderr] 
Dec 13 18:41:20.130 INFO [stderr] warning: variable does not need to be mutable
Dec 13 18:41:20.130 INFO [stderr]    --> src/main.rs:139:9
Dec 13 18:41:20.130 INFO [stderr]     |
Dec 13 18:41:20.130 INFO [stderr] 139 |     let mut s = String::from("hello world");
Dec 13 18:41:20.130 INFO [stderr]     |         ----^
Dec 13 18:41:20.130 INFO [stderr]     |         |
Dec 13 18:41:20.130 INFO [stderr]     |         help: remove this `mut`
Dec 13 18:41:20.130 INFO [stderr]     |
Dec 13 18:41:20.131 INFO [stderr]     = note: #[warn(unused_mut)] on by default
Dec 13 18:41:20.131 INFO [stderr] 
Dec 13 18:41:20.143 INFO [stderr] warning: variant is never constructed: `NetworkError`
Dec 13 18:41:20.143 INFO [stderr]    --> src/main.rs:252:9
Dec 13 18:41:20.143 INFO [stderr]     |
Dec 13 18:41:20.143 INFO [stderr] 252 |         NetworkError,
Dec 13 18:41:20.143 INFO [stderr]     |         ^^^^^^^^^^^^
Dec 13 18:41:20.143 INFO [stderr]     |
Dec 13 18:41:20.143 INFO [stderr]     = note: #[warn(dead_code)] on by default
Dec 13 18:41:20.143 INFO [stderr] 
Dec 13 18:41:20.143 INFO [stderr] warning: variant is never constructed: `SerilizationError`
Dec 13 18:41:20.143 INFO [stderr]    --> src/main.rs:253:9
Dec 13 18:41:20.143 INFO [stderr]     |
Dec 13 18:41:20.143 INFO [stderr] 253 |         SerilizationError(String),
Dec 13 18:41:20.143 INFO [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 13 18:41:20.143 INFO [stderr] 
Dec 13 18:41:20.143 INFO [stderr] warning: function is never used: `closures`
Dec 13 18:41:20.143 INFO [stderr]    --> src/main.rs:310:1
Dec 13 18:41:20.143 INFO [stderr]     |
Dec 13 18:41:20.143 INFO [stderr] 310 | fn closures() {
Dec 13 18:41:20.143 INFO [stderr]     | ^^^^^^^^^^^^^
Dec 13 18:41:20.143 INFO [stderr] 
Dec 13 18:41:20.143 INFO [stderr] warning: variable `className` should have a snake case name such as `class_name`
Dec 13 18:41:20.143 INFO [stderr]    --> src/main.rs:264:41
Dec 13 18:41:20.143 INFO [stderr]     |
Dec 13 18:41:20.143 INFO [stderr] 264 |         RPCCallError::SerilizationError(className) => {
Dec 13 18:41:20.143 INFO [stderr]     |                                         ^^^^^^^^^
Dec 13 18:41:20.143 INFO [stderr]     |
Dec 13 18:41:20.143 INFO [stderr]     = note: #[warn(non_snake_case)] on by default
Dec 13 18:41:20.143 INFO [stderr] 
Dec 13 18:41:20.455 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.91s
Dec 13 18:41:20.455 INFO [stderr] su: No module specific data is present
Dec 13 18:41:21.489 INFO running `"docker" "inspect" "1292d38cacae3dcfe167ae7f2072deec7b0d39394686e6472eb73b8502788b31"`
Dec 13 18:41:21.730 INFO running `"docker" "rm" "-f" "1292d38cacae3dcfe167ae7f2072deec7b0d39394686e6472eb73b8502788b31"`
Dec 13 18:41:22.179 INFO [stdout] 1292d38cacae3dcfe167ae7f2072deec7b0d39394686e6472eb73b8502788b31
Dec 13 18:41:22.181 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56550/worker-1/try#aa49d8ef14939ddec0e34b346b60174a5673d48f:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-1/pr-56550/try#aa49d8ef14939ddec0e34b346b60174a5673d48f:/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 +aa49d8ef14939ddec0e34b346b60174a5673d48f-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 13 18:41:22.747 INFO [stdout] 0bf4ce28e5fa779b74f2e72976f34e7325481a0d88f85bccdd29a3bded7d628b
Dec 13 18:41:22.751 INFO running `"docker" "start" "-a" "0bf4ce28e5fa779b74f2e72976f34e7325481a0d88f85bccdd29a3bded7d628b"`
Dec 13 18:41:24.075 INFO [stderr] usermod: no changes
Dec 13 18:41:24.143 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.03s
Dec 13 18:41:24.159 INFO [stderr]      Running /target/debug/deps/learn_rust-114fa80b10c9e920
Dec 13 18:41:24.159 INFO [stdout] 
Dec 13 18:41:24.159 INFO [stderr] su: No module specific data is present
Dec 13 18:41:24.159 INFO [stdout] running 0 tests
Dec 13 18:41:24.159 INFO [stdout] 
Dec 13 18:41:24.159 INFO [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
Dec 13 18:41:24.159 INFO [stdout] 
Dec 13 18:41:25.095 INFO running `"docker" "inspect" "0bf4ce28e5fa779b74f2e72976f34e7325481a0d88f85bccdd29a3bded7d628b"`
Dec 13 18:41:25.381 INFO running `"docker" "rm" "-f" "0bf4ce28e5fa779b74f2e72976f34e7325481a0d88f85bccdd29a3bded7d628b"`
Dec 13 18:41:25.663 INFO [stdout] 0bf4ce28e5fa779b74f2e72976f34e7325481a0d88f85bccdd29a3bded7d628b