[INFO] fetching crate unic-idna-punycode 0.9.0...
[INFO] checking unic-idna-punycode-0.9.0 against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] extracting crate unic-idna-punycode 0.9.0 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate unic-idna-punycode 0.9.0 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 crates.io crate unic-idna-punycode 0.9.0
[INFO] finished tweaking crates.io crate unic-idna-punycode 0.9.0
[INFO] tweaked toml for crates.io crate unic-idna-punycode 0.9.0 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 2 packages
[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] 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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2693831c8121aae8f8fc0a7983ab97b13e24a6d122d18ad09dd8d4a928849358
[INFO] running `Command { std: "docker" "start" "-a" "2693831c8121aae8f8fc0a7983ab97b13e24a6d122d18ad09dd8d4a928849358", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2693831c8121aae8f8fc0a7983ab97b13e24a6d122d18ad09dd8d4a928849358", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2693831c8121aae8f8fc0a7983ab97b13e24a6d122d18ad09dd8d4a928849358", kill_on_drop: false }`
[INFO] [stdout] 2693831c8121aae8f8fc0a7983ab97b13e24a6d122d18ad09dd8d4a928849358
[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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ab20ceb677defebbdfb09dc3e677104e3d5dd22d1f5f9f71ee8cd866817e01e0
[INFO] running `Command { std: "docker" "start" "-a" "ab20ceb677defebbdfb09dc3e677104e3d5dd22d1f5f9f71ee8cd866817e01e0", kill_on_drop: false }`
[INFO] [stderr]     Checking unic-idna-punycode v0.9.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.05s
[INFO] running `Command { std: "docker" "inspect" "ab20ceb677defebbdfb09dc3e677104e3d5dd22d1f5f9f71ee8cd866817e01e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ab20ceb677defebbdfb09dc3e677104e3d5dd22d1f5f9f71ee8cd866817e01e0", kill_on_drop: false }`
[INFO] [stdout] ab20ceb677defebbdfb09dc3e677104e3d5dd22d1f5f9f71ee8cd866817e01e0
[INFO] checking unic-idna-punycode-0.9.0 against try#3a4bc97f6385a3aa300a4fd689b44350e54fd676 for no-never-type-fallback
[INFO] extracting crate unic-idna-punycode 0.9.0 into /workspace/builds/worker-7-tc2/source
[INFO] validating manifest of crates.io crate unic-idna-punycode 0.9.0 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 crates.io crate unic-idna-punycode 0.9.0
[INFO] finished tweaking crates.io crate unic-idna-punycode 0.9.0
[INFO] tweaked toml for crates.io crate unic-idna-punycode 0.9.0 written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[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-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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c693b495c0782f7dcd0ba537c15a5a6e2adef024e52261421a9a07a9a545fac5
[INFO] running `Command { std: "docker" "start" "-a" "c693b495c0782f7dcd0ba537c15a5a6e2adef024e52261421a9a07a9a545fac5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c693b495c0782f7dcd0ba537c15a5a6e2adef024e52261421a9a07a9a545fac5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c693b495c0782f7dcd0ba537c15a5a6e2adef024e52261421a9a07a9a545fac5", kill_on_drop: false }`
[INFO] [stdout] c693b495c0782f7dcd0ba537c15a5a6e2adef024e52261421a9a07a9a545fac5
[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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3c982c8583c70465da1aa8a8718af408921038abf87c5bfa869b3aa421a73337
[INFO] running `Command { std: "docker" "start" "-a" "3c982c8583c70465da1aa8a8718af408921038abf87c5bfa869b3aa421a73337", kill_on_drop: false }`
[INFO] [stderr]     Checking rustc-serialize v0.3.25
[INFO] [stderr]     Checking unic-idna-punycode v0.9.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0282]: type annotations needed
[INFO] [stdout]     --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/rustc-serialize-0.3.25/src/json.rs:1387:20
[INFO] [stdout]      |
[INFO] [stdout] 1387 |             _ => { 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] error: could not compile `rustc-serialize` (lib) due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "3c982c8583c70465da1aa8a8718af408921038abf87c5bfa869b3aa421a73337", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c982c8583c70465da1aa8a8718af408921038abf87c5bfa869b3aa421a73337", kill_on_drop: false }`
[INFO] [stdout] 3c982c8583c70465da1aa8a8718af408921038abf87c5bfa869b3aa421a73337