[INFO] cloning repository https://github.com/suxiaoshao/compiler-lab
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/suxiaoshao/compiler-lab" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsuxiaoshao%2Fcompiler-lab", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsuxiaoshao%2Fcompiler-lab'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ad0e02015632a5cce4aae840068d0d816e3eb690
[INFO] checking suxiaoshao/compiler-lab against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsuxiaoshao%2Fcompiler-lab" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/suxiaoshao/compiler-lab 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/suxiaoshao/compiler-lab
[INFO] finished tweaking git repo https://github.com/suxiaoshao/compiler-lab
[INFO] tweaked toml for git repo https://github.com/suxiaoshao/compiler-lab written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/suxiaoshao/compiler-lab 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 063c3d1effcc4acdc2f61d305eb4475a50c8884f59a48f3c74e740c4318351c7
[INFO] running `Command { std: "docker" "start" "-a" "063c3d1effcc4acdc2f61d305eb4475a50c8884f59a48f3c74e740c4318351c7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "063c3d1effcc4acdc2f61d305eb4475a50c8884f59a48f3c74e740c4318351c7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "063c3d1effcc4acdc2f61d305eb4475a50c8884f59a48f3c74e740c4318351c7", kill_on_drop: false }`
[INFO] [stdout] 063c3d1effcc4acdc2f61d305eb4475a50c8884f59a48f3c74e740c4318351c7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 87a7d96cbf6c5fb1106626f5261402f20cb38c31890f68994729883bd0453970
[INFO] running `Command { std: "docker" "start" "-a" "87a7d96cbf6c5fb1106626f5261402f20cb38c31890f68994729883bd0453970", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling serde v1.0.126
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking vec_map v0.8.2
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking colored v2.0.0
[INFO] [stderr]     Checking compiler-lab v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `position` is never read
[INFO] [stdout]   --> src/tokenizer/read_token_state/empty.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub(in crate::tokenizer) struct Empty {
[INFO] [stdout]    |                                 ----- field in this struct
[INFO] [stdout] 23 |     position: Position,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Empty` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `scope` is never read
[INFO] [stdout]   --> src/translator/identifier.rs:30:31
[INFO] [stdout]    |
[INFO] [stdout] 27 | pub(in crate::translator) struct Identifier {
[INFO] [stdout]    |                                  ---------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 30 |     pub(in crate::translator) scope: i32,
[INFO] [stdout]    |                               ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Identifier` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `position` is never read
[INFO] [stdout]   --> src/tokenizer/read_token_state/empty.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub(in crate::tokenizer) struct Empty {
[INFO] [stdout]    |                                 ----- field in this struct
[INFO] [stdout] 23 |     position: Position,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Empty` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `scope` is never read
[INFO] [stdout]   --> src/translator/identifier.rs:30:31
[INFO] [stdout]    |
[INFO] [stdout] 27 | pub(in crate::translator) struct Identifier {
[INFO] [stdout]    |                                  ---------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 30 |     pub(in crate::translator) scope: i32,
[INFO] [stdout]    |                               ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Identifier` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 15.83s
[INFO] running `Command { std: "docker" "inspect" "87a7d96cbf6c5fb1106626f5261402f20cb38c31890f68994729883bd0453970", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "87a7d96cbf6c5fb1106626f5261402f20cb38c31890f68994729883bd0453970", kill_on_drop: false }`
[INFO] [stdout] 87a7d96cbf6c5fb1106626f5261402f20cb38c31890f68994729883bd0453970
[INFO] checking suxiaoshao/compiler-lab against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsuxiaoshao%2Fcompiler-lab" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/suxiaoshao/compiler-lab 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/suxiaoshao/compiler-lab
[INFO] finished tweaking git repo https://github.com/suxiaoshao/compiler-lab
[INFO] tweaked toml for git repo https://github.com/suxiaoshao/compiler-lab written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/suxiaoshao/compiler-lab 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-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] b389cb2504372d586fefd96763138e9ff97e94b90adaf6085c685fd2ff768987
[INFO] running `Command { std: "docker" "start" "-a" "b389cb2504372d586fefd96763138e9ff97e94b90adaf6085c685fd2ff768987", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b389cb2504372d586fefd96763138e9ff97e94b90adaf6085c685fd2ff768987", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b389cb2504372d586fefd96763138e9ff97e94b90adaf6085c685fd2ff768987", kill_on_drop: false }`
[INFO] [stdout] b389cb2504372d586fefd96763138e9ff97e94b90adaf6085c685fd2ff768987
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] e42dd73cf820f0485a0cbbd4ac28911daf01f005f8322d00d3957adeefbfaaa5
[INFO] running `Command { std: "docker" "start" "-a" "e42dd73cf820f0485a0cbbd4ac28911daf01f005f8322d00d3957adeefbfaaa5", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling serde v1.0.126
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking vec_map v0.8.2
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking colored v2.0.0
[INFO] [stderr]     Checking compiler-lab v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `position` is never read
[INFO] [stdout]   --> src/tokenizer/read_token_state/empty.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub(in crate::tokenizer) struct Empty {
[INFO] [stdout]    |                                 ----- field in this struct
[INFO] [stdout] 23 |     position: Position,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Empty` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `scope` is never read
[INFO] [stdout]   --> src/translator/identifier.rs:30:31
[INFO] [stdout]    |
[INFO] [stdout] 27 | pub(in crate::translator) struct Identifier {
[INFO] [stdout]    |                                  ---------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 30 |     pub(in crate::translator) scope: i32,
[INFO] [stdout]    |                               ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Identifier` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `position` is never read
[INFO] [stdout]   --> src/tokenizer/read_token_state/empty.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub(in crate::tokenizer) struct Empty {
[INFO] [stdout]    |                                 ----- field in this struct
[INFO] [stdout] 23 |     position: Position,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Empty` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `scope` is never read
[INFO] [stdout]   --> src/translator/identifier.rs:30:31
[INFO] [stdout]    |
[INFO] [stdout] 27 | pub(in crate::translator) struct Identifier {
[INFO] [stdout]    |                                  ---------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 30 |     pub(in crate::translator) scope: i32,
[INFO] [stdout]    |                               ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Identifier` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 16.07s
[INFO] running `Command { std: "docker" "inspect" "e42dd73cf820f0485a0cbbd4ac28911daf01f005f8322d00d3957adeefbfaaa5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e42dd73cf820f0485a0cbbd4ac28911daf01f005f8322d00d3957adeefbfaaa5", kill_on_drop: false }`
[INFO] [stdout] e42dd73cf820f0485a0cbbd4ac28911daf01f005f8322d00d3957adeefbfaaa5