[INFO] cloning repository https://github.com/Tester-JasonWang/rust_demo
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Tester-JasonWang/rust_demo" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTester-JasonWang%2Frust_demo", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTester-JasonWang%2Frust_demo'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a73073b465107fc28da3ae9c1e9a6407d1378929
[INFO] checking Tester-JasonWang/rust_demo against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTester-JasonWang%2Frust_demo" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Tester-JasonWang/rust_demo on toolchain ceab6128fa48a616bfd3e3adf4bc80133b8ee223
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Tester-JasonWang/rust_demo
[INFO] finished tweaking git repo https://github.com/Tester-JasonWang/rust_demo
[INFO] tweaked toml for git repo https://github.com/Tester-JasonWang/rust_demo written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Tester-JasonWang/rust_demo 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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded windows_macros v0.9.1
[INFO] [stderr]   Downloaded serde v1.0.177
[INFO] [stderr]   Downloaded ferris-says v0.2.1
[INFO] [stderr]   Downloaded os_str_bytes v6.5.1
[INFO] [stderr]   Downloaded smallvec v0.4.5
[INFO] [stderr]   Downloaded textwrap v0.13.4
[INFO] [stderr]   Downloaded windows v0.9.1
[INFO] [stderr]   Downloaded smawk v0.3.1
[INFO] [stderr]   Downloaded syn v2.0.27
[INFO] [stderr]   Downloaded serde_derive v1.0.177
[INFO] [stderr]   Downloaded windows_gen v0.9.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 111ca0b9676b18f9b07dc57aaedb30f61ba20d3f0dd61911b24163135e342501
[INFO] running `Command { std: "docker" "start" "-a" "111ca0b9676b18f9b07dc57aaedb30f61ba20d3f0dd61911b24163135e342501", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "111ca0b9676b18f9b07dc57aaedb30f61ba20d3f0dd61911b24163135e342501", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "111ca0b9676b18f9b07dc57aaedb30f61ba20d3f0dd61911b24163135e342501", kill_on_drop: false }`
[INFO] [stdout] 111ca0b9676b18f9b07dc57aaedb30f61ba20d3f0dd61911b24163135e342501
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 361439a5bc5489c7d674db97774f7d88a74567af958a88fcd0f3761ac418fb9c
[INFO] running `Command { std: "docker" "start" "-a" "361439a5bc5489c7d674db97774f7d88a74567af958a88fcd0f3761ac418fb9c", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling proc-macro2 v1.0.66
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling num-bigint v0.4.3
[INFO] [stderr]    Compiling libc v0.2.147
[INFO] [stderr]     Checking unicode-ident v1.0.8
[INFO] [stderr]    Compiling num-rational v0.4.1
[INFO] [stderr]    Compiling num-iter v0.1.43
[INFO] [stderr]    Compiling serde v1.0.177
[INFO] [stderr]     Checking linked-hash-map v0.5.6
[INFO] [stderr]     Checking unicode-width v0.1.10
[INFO] [stderr]    Compiling serde_derive v1.0.177
[INFO] [stderr]     Checking smawk v0.3.1
[INFO] [stderr]     Checking os_str_bytes v6.5.1
[INFO] [stderr]     Checking yaml-rust v0.4.5
[INFO] [stderr]     Checking textwrap v0.13.4
[INFO] [stderr]    Compiling quote v1.0.32
[INFO] [stderr]     Checking clap_lex v0.2.4
[INFO] [stderr]     Checking const-sha1 v0.2.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking smallvec v0.4.5
[INFO] [stderr]     Checking termcolor v1.2.0
[INFO] [stderr]     Checking windows_gen v0.9.1
[INFO] [stderr]     Checking ferris-says v0.2.1
[INFO] [stderr]     Checking clap v3.2.25
[INFO] [stderr]     Checking num-integer v0.1.45
[INFO] [stderr]     Checking num-complex v0.4.3
[INFO] [stderr]     Checking num v0.4.0
[INFO] [stderr]     Checking serde_yaml v0.8.26
[INFO] [stderr]    Compiling windows_macros v0.9.1
[INFO] [stderr]     Checking windows v0.9.1
[INFO] [stderr]     Checking rust_demo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `MySpecialFormatter` is never constructed
[INFO] [stdout]   --> src/lib.rs:48:8
[INFO] [stdout]    |
[INFO] [stdout] 48 | struct MySpecialFormatter;
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_four` is never used
[INFO] [stdout]   --> src/lib.rs:43:12
[INFO] [stdout]    |
[INFO] [stdout] 43 |     pub fn add_four(x: i32) -> Option<i32> {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `MySpecialFormatter` is never constructed
[INFO] [stdout]   --> src/lib.rs:48:8
[INFO] [stdout]    |
[INFO] [stdout] 48 | struct MySpecialFormatter;
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_four` is never used
[INFO] [stdout]   --> src/lib.rs:43:12
[INFO] [stdout]    |
[INFO] [stdout] 43 |     pub fn add_four(x: i32) -> Option<i32> {
[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] [stdout] warning: function `div` is never used
[INFO] [stdout]   --> src/demo.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub fn div(a: i32, b: i32) -> i32 {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `try_div` is never used
[INFO] [stdout]   --> src/demo.rs:31:8
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub fn try_div(a: i32, b: i32) -> Result<i32, String> {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `div` is never used
[INFO] [stdout]   --> src/demo.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub fn div(a: i32, b: i32) -> i32 {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `try_div` is never used
[INFO] [stdout]   --> src/demo.rs:31:8
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub fn try_div(a: i32, b: i32) -> Result<i32, String> {
[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 5.55s
[INFO] running `Command { std: "docker" "inspect" "361439a5bc5489c7d674db97774f7d88a74567af958a88fcd0f3761ac418fb9c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "361439a5bc5489c7d674db97774f7d88a74567af958a88fcd0f3761ac418fb9c", kill_on_drop: false }`
[INFO] [stdout] 361439a5bc5489c7d674db97774f7d88a74567af958a88fcd0f3761ac418fb9c
[INFO] checking Tester-JasonWang/rust_demo against try#3a4bc97f6385a3aa300a4fd689b44350e54fd676 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FTester-JasonWang%2Frust_demo" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Tester-JasonWang/rust_demo on toolchain 3a4bc97f6385a3aa300a4fd689b44350e54fd676
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Tester-JasonWang/rust_demo
[INFO] finished tweaking git repo https://github.com/Tester-JasonWang/rust_demo
[INFO] tweaked toml for git repo https://github.com/Tester-JasonWang/rust_demo written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/Tester-JasonWang/rust_demo 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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 139fe1233bd10f4ac6927601da3b254e879de8ea29e880ff755aab409b868ccb
[INFO] running `Command { std: "docker" "start" "-a" "139fe1233bd10f4ac6927601da3b254e879de8ea29e880ff755aab409b868ccb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "139fe1233bd10f4ac6927601da3b254e879de8ea29e880ff755aab409b868ccb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "139fe1233bd10f4ac6927601da3b254e879de8ea29e880ff755aab409b868ccb", kill_on_drop: false }`
[INFO] [stdout] 139fe1233bd10f4ac6927601da3b254e879de8ea29e880ff755aab409b868ccb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f02569da2681886750b380dc76f0a2ddbcee39c831ab0da01839fb8b3e58f559
[INFO] running `Command { std: "docker" "start" "-a" "f02569da2681886750b380dc76f0a2ddbcee39c831ab0da01839fb8b3e58f559", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.66
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling num-bigint v0.4.3
[INFO] [stderr]    Compiling libc v0.2.147
[INFO] [stderr]     Checking unicode-ident v1.0.8
[INFO] [stderr]    Compiling num-rational v0.4.1
[INFO] [stderr]    Compiling num-iter v0.1.43
[INFO] [stderr]    Compiling serde v1.0.177
[INFO] [stderr]     Checking linked-hash-map v0.5.6
[INFO] [stderr]     Checking os_str_bytes v6.5.1
[INFO] [stderr]     Checking smawk v0.3.1
[INFO] [stderr]    Compiling serde_derive v1.0.177
[INFO] [stderr]     Checking unicode-width v0.1.10
[INFO] [stdout] error[E0282]: type annotations needed
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/serde_derive-1.0.177/src/lib_precompiled.rs:68:9
[INFO] [stdout]    |
[INFO] [stdout] 68 |         panic!();
[INFO] [stdout]    |         ^^^^^^^^ cannot infer type
[INFO] [stdout]    |
[INFO] [stdout]    = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0282`.
[INFO] [stdout] 
[INFO] [stderr]     Checking yaml-rust v0.4.5
[INFO] [stderr] error: could not compile `serde_derive` (lib) due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "f02569da2681886750b380dc76f0a2ddbcee39c831ab0da01839fb8b3e58f559", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f02569da2681886750b380dc76f0a2ddbcee39c831ab0da01839fb8b3e58f559", kill_on_drop: false }`
[INFO] [stdout] f02569da2681886750b380dc76f0a2ddbcee39c831ab0da01839fb8b3e58f559