[INFO] cloning repository https://github.com/thumperca/mutex-experiments
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/thumperca/mutex-experiments" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fthumperca%2Fmutex-experiments", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fthumperca%2Fmutex-experiments'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 052da1010a141b49b486ea496ed21a0b2ce28104
[INFO] checking thumperca/mutex-experiments against master#1f12b9b0fdbe735968ac002792a720f0ba4faca6 for crater-rollup-uwu
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fthumperca%2Fmutex-experiments" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/thumperca/mutex-experiments on toolchain 1f12b9b0fdbe735968ac002792a720f0ba4faca6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/thumperca/mutex-experiments
[INFO] finished tweaking git repo https://github.com/thumperca/mutex-experiments
[INFO] tweaked toml for git repo https://github.com/thumperca/mutex-experiments written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/thumperca/mutex-experiments 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" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded atomic-wait v1.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1edd0ad2e82546fb5331e36cbf69869a4ca9a803ba6e79d00ccde551285a3667
[INFO] running `Command { std: "docker" "start" "-a" "1edd0ad2e82546fb5331e36cbf69869a4ca9a803ba6e79d00ccde551285a3667", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1edd0ad2e82546fb5331e36cbf69869a4ca9a803ba6e79d00ccde551285a3667", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1edd0ad2e82546fb5331e36cbf69869a4ca9a803ba6e79d00ccde551285a3667", kill_on_drop: false }`
[INFO] [stdout] 1edd0ad2e82546fb5331e36cbf69869a4ca9a803ba6e79d00ccde551285a3667
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 21f8c8d73ad271b36d7c3bc770221d081f66dfdb2fa636aec39b2700bdac58cf
[INFO] running `Command { std: "docker" "start" "-a" "21f8c8d73ad271b36d7c3bc770221d081f66dfdb2fa636aec39b2700bdac58cf", kill_on_drop: false }`
[INFO] [stderr]     Checking atomic-wait v1.1.0
[INFO] [stderr]     Checking mutex v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> src/fair_mutex.rs:115:9
[INFO] [stdout]     |
[INFO] [stdout] 115 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::sync::Arc`
[INFO] [stdout]    --> src/fair_mutex.rs:116:9
[INFO] [stdout]     |
[INFO] [stdout] 116 |     use std::sync::Arc;
[INFO] [stdout]     |         ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> src/kernel_wait_mutex.rs:76:9
[INFO] [stdout]    |
[INFO] [stdout] 76 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::sync::Arc`
[INFO] [stdout]   --> src/kernel_wait_mutex.rs:77:9
[INFO] [stdout]    |
[INFO] [stdout] 77 |     use std::sync::Arc;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> src/raw_mutex.rs:56:9
[INFO] [stdout]    |
[INFO] [stdout] 56 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::sync::Arc`
[INFO] [stdout]   --> src/raw_mutex.rs:57:9
[INFO] [stdout]    |
[INFO] [stdout] 57 |     use std::sync::Arc;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> src/safe_spin_mutex.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:18:13
[INFO] [stdout]    |
[INFO] [stdout] 18 |         for i in 0..100_000 {
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/fair_mutex.rs:17:12
[INFO] [stdout]    |
[INFO] [stdout] 16 | impl<'a, T> MutexGuard<'a, T> {
[INFO] [stdout]    | ----------------------------- associated function in this implementation
[INFO] [stdout] 17 |     pub fn new(mux: &'a Mutex<T>) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `lock` are never used
[INFO] [stdout]   --> src/fair_mutex.rs:77:12
[INFO] [stdout]    |
[INFO] [stdout] 76 | impl<T> Mutex<T> {
[INFO] [stdout]    | ---------------- associated items in this implementation
[INFO] [stdout] 77 |     pub fn new(value: T) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 85 |     pub fn lock(&self) -> MutexGuard<T> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/kernel_wait_mutex.rs:15:12
[INFO] [stdout]    |
[INFO] [stdout] 14 | impl<'a, T> MutexGuard<'a, T> {
[INFO] [stdout]    | ----------------------------- associated function in this implementation
[INFO] [stdout] 15 |     pub fn new(mux: &'a Mutex<T>) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `lock` are never used
[INFO] [stdout]   --> src/kernel_wait_mutex.rs:57:12
[INFO] [stdout]    |
[INFO] [stdout] 56 | impl<T> Mutex<T> {
[INFO] [stdout]    | ---------------- associated items in this implementation
[INFO] [stdout] 57 |     pub fn new(value: T) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 64 |     pub fn lock(&self) -> MutexGuard<T> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/raw_mutex.rs:24:12
[INFO] [stdout]    |
[INFO] [stdout] 23 | impl<T> Mutex<T> {
[INFO] [stdout]    | ---------------- associated function in this implementation
[INFO] [stdout] 24 |     pub fn new(value: T) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Mutex` is never constructed
[INFO] [stdout]   --> src/unsafe_spin_mutex.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 | pub struct Mutex<T> {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `lock`, and `unlock` are never used
[INFO] [stdout]   --> src/unsafe_spin_mutex.rs:26:12
[INFO] [stdout]    |
[INFO] [stdout] 25 | impl<T> Mutex<T> {
[INFO] [stdout]    | ---------------- associated items in this implementation
[INFO] [stdout] 26 |     pub fn new(value: T) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 33 |     pub fn lock(&self) -> &mut T {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 42 |     pub unsafe fn unlock(&self) {
[INFO] [stdout]    |                   ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/fair_mutex.rs:123:17
[INFO] [stdout]     |
[INFO] [stdout] 123 |             for i in 0..10_000 {
[INFO] [stdout]     |                 ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/kernel_wait_mutex.rs:84:17
[INFO] [stdout]    |
[INFO] [stdout] 84 |             for i in 0..10_000 {
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:18:13
[INFO] [stdout]    |
[INFO] [stdout] 18 |         for i in 0..100_000 {
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Mutex` is never constructed
[INFO] [stdout]   --> src/unsafe_spin_mutex.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 | pub struct Mutex<T> {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `lock`, and `unlock` are never used
[INFO] [stdout]   --> src/unsafe_spin_mutex.rs:26:12
[INFO] [stdout]    |
[INFO] [stdout] 25 | impl<T> Mutex<T> {
[INFO] [stdout]    | ---------------- associated items in this implementation
[INFO] [stdout] 26 |     pub fn new(value: T) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 33 |     pub fn lock(&self) -> &mut T {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 42 |     pub unsafe fn unlock(&self) {
[INFO] [stdout]    |                   ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.21s
[INFO] running `Command { std: "docker" "inspect" "21f8c8d73ad271b36d7c3bc770221d081f66dfdb2fa636aec39b2700bdac58cf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21f8c8d73ad271b36d7c3bc770221d081f66dfdb2fa636aec39b2700bdac58cf", kill_on_drop: false }`
[INFO] [stdout] 21f8c8d73ad271b36d7c3bc770221d081f66dfdb2fa636aec39b2700bdac58cf