[INFO] cloning repository https://github.com/Spoonbender/rust-intro-demos
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Spoonbender/rust-intro-demos" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSpoonbender%2Frust-intro-demos", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSpoonbender%2Frust-intro-demos'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7c2c50f1bdf7a50fc484ac7d9f4e74240f24bdd2
[INFO] checking Spoonbender/rust-intro-demos against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSpoonbender%2Frust-intro-demos" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Spoonbender/rust-intro-demos 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/Spoonbender/rust-intro-demos
[INFO] finished tweaking git repo https://github.com/Spoonbender/rust-intro-demos
[INFO] tweaked toml for git repo https://github.com/Spoonbender/rust-intro-demos written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Spoonbender/rust-intro-demos 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]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] ce92cfa3c87c70903fde53936c1c7c8ec88e383afacfc06e9d046624051f5265
[INFO] running `Command { std: "docker" "start" "-a" "ce92cfa3c87c70903fde53936c1c7c8ec88e383afacfc06e9d046624051f5265", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ce92cfa3c87c70903fde53936c1c7c8ec88e383afacfc06e9d046624051f5265", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ce92cfa3c87c70903fde53936c1c7c8ec88e383afacfc06e9d046624051f5265", kill_on_drop: false }`
[INFO] [stdout] ce92cfa3c87c70903fde53936c1c7c8ec88e383afacfc06e9d046624051f5265
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] 8aef8af44bc1ba1dfb6514c956c5b03ab2be629266c240be73cb3513aff56e3a
[INFO] running `Command { std: "docker" "start" "-a" "8aef8af44bc1ba1dfb6514c956c5b03ab2be629266c240be73cb3513aff56e3a", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.86
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]     Checking getrandom v0.2.2
[INFO] [stderr]     Checking time v0.1.43
[INFO] [stderr]     Checking rand_core v0.6.2
[INFO] [stderr]     Checking rand_chacha v0.3.0
[INFO] [stderr]     Checking rand v0.8.3
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]     Checking rust-intro-demos v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `ops::DerefMut`
[INFO] [stdout]  --> examples/shared_state.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 |     ops::DerefMut,
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main2` is never used
[INFO] [stdout]   --> examples/shared_state.rs:26:4
[INFO] [stdout]    |
[INFO] [stdout] 26 | fn main2() {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `do_something2` is never used
[INFO] [stdout]   --> examples/errors.rs:23:4
[INFO] [stdout]    |
[INFO] [stdout] 23 | fn do_something2(file_name: &str) -> Result<()> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `do_something3` is never used
[INFO] [stdout]   --> examples/errors.rs:29:4
[INFO] [stdout]    |
[INFO] [stdout] 29 | fn do_something3(file_name: &str) -> Result<()> {
[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] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.93s
[INFO] running `Command { std: "docker" "inspect" "8aef8af44bc1ba1dfb6514c956c5b03ab2be629266c240be73cb3513aff56e3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8aef8af44bc1ba1dfb6514c956c5b03ab2be629266c240be73cb3513aff56e3a", kill_on_drop: false }`
[INFO] [stdout] 8aef8af44bc1ba1dfb6514c956c5b03ab2be629266c240be73cb3513aff56e3a
[INFO] checking Spoonbender/rust-intro-demos against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSpoonbender%2Frust-intro-demos" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Spoonbender/rust-intro-demos on toolchain 2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Spoonbender/rust-intro-demos
[INFO] finished tweaking git repo https://github.com/Spoonbender/rust-intro-demos
[INFO] tweaked toml for git repo https://github.com/Spoonbender/rust-intro-demos written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/Spoonbender/rust-intro-demos 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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 72956c6c14196c4abb2bd46f74b046da2b71a73f5fb658c8c60c804ce149f683
[INFO] running `Command { std: "docker" "start" "-a" "72956c6c14196c4abb2bd46f74b046da2b71a73f5fb658c8c60c804ce149f683", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "72956c6c14196c4abb2bd46f74b046da2b71a73f5fb658c8c60c804ce149f683", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "72956c6c14196c4abb2bd46f74b046da2b71a73f5fb658c8c60c804ce149f683", kill_on_drop: false }`
[INFO] [stdout] 72956c6c14196c4abb2bd46f74b046da2b71a73f5fb658c8c60c804ce149f683
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 334a60ceb2672b67067a77856c1827087acbc743a2d2c0d07f3481d5edd385b2
[INFO] running `Command { std: "docker" "start" "-a" "334a60ceb2672b67067a77856c1827087acbc743a2d2c0d07f3481d5edd385b2", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.86
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]     Checking getrandom v0.2.2
[INFO] [stderr]     Checking time v0.1.43
[INFO] [stderr]     Checking rand_core v0.6.2
[INFO] [stderr]     Checking rand_chacha v0.3.0
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]     Checking rand v0.8.3
[INFO] [stderr]     Checking rust-intro-demos v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `ops::DerefMut`
[INFO] [stdout]  --> examples/shared_state.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 |     ops::DerefMut,
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `main2` is never used
[INFO] [stdout]   --> examples/shared_state.rs:26:4
[INFO] [stdout]    |
[INFO] [stdout] 26 | fn main2() {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `do_something2` is never used
[INFO] [stdout]   --> examples/errors.rs:23:4
[INFO] [stdout]    |
[INFO] [stdout] 23 | fn do_something2(file_name: &str) -> Result<()> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `do_something3` is never used
[INFO] [stdout]   --> examples/errors.rs:29:4
[INFO] [stdout]    |
[INFO] [stdout] 29 | fn do_something3(file_name: &str) -> Result<()> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ingress_thread`
[INFO] [stdout]   --> examples/message_passing.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let ingress_thread = thread::spawn(move || {
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_ingress_thread`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.79s
[INFO] running `Command { std: "docker" "inspect" "334a60ceb2672b67067a77856c1827087acbc743a2d2c0d07f3481d5edd385b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "334a60ceb2672b67067a77856c1827087acbc743a2d2c0d07f3481d5edd385b2", kill_on_drop: false }`
[INFO] [stdout] 334a60ceb2672b67067a77856c1827087acbc743a2d2c0d07f3481d5edd385b2