[INFO] fetching crate serializers 0.2.3...
[INFO] checking serializers-0.2.3 against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] extracting crate serializers 0.2.3 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate serializers 0.2.3 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 crates.io crate serializers 0.2.3
[INFO] finished tweaking crates.io crate serializers 0.2.3
[INFO] tweaked toml for crates.io crate serializers 0.2.3 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 29 packages
[INFO] [stderr]       Adding bitflags v0.9.1 (latest: v2.5.0)
[INFO] [stderr]       Adding idna v0.1.5 (latest: v0.5.0)
[INFO] [stderr]       Adding itertools v0.7.11 (latest: v0.12.1)
[INFO] [stderr]       Adding percent-encoding v1.0.1 (latest: v2.3.1)
[INFO] [stderr]       Adding pulldown-cmark v0.1.2 (latest: v0.10.2)
[INFO] [stderr]       Adding quote v0.3.15 (latest: v1.0.35)
[INFO] [stderr]       Adding semver-parser v0.7.0 (latest: v0.10.2)
[INFO] [stderr]       Adding syn v0.11.11 (latest: v2.0.58)
[INFO] [stderr]       Adding toml v0.4.10 (latest: v0.8.12)
[INFO] [stderr]       Adding unicode-xid v0.0.4 (latest: v0.2.4)
[INFO] [stderr]       Adding url v1.7.2 (latest: v2.5.0)
[INFO] [stderr]       Adding version-sync v0.5.0 (latest: v0.9.5)
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded version-sync v0.5.0
[INFO] [stderr]   Downloaded pulldown-cmark v0.1.2
[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] bb71d38a8e585c19968c07b06f4b8f1981981820697714d974abbc1c6990703d
[INFO] running `Command { std: "docker" "start" "-a" "bb71d38a8e585c19968c07b06f4b8f1981981820697714d974abbc1c6990703d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bb71d38a8e585c19968c07b06f4b8f1981981820697714d974abbc1c6990703d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bb71d38a8e585c19968c07b06f4b8f1981981820697714d974abbc1c6990703d", kill_on_drop: false }`
[INFO] [stdout] bb71d38a8e585c19968c07b06f4b8f1981981820697714d974abbc1c6990703d
[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] 1de8a300dd5635a19a8cd57b910ad9e3664249b13aa4903b6b1f8739cd2dbaf3
[INFO] running `Command { std: "docker" "start" "-a" "1de8a300dd5635a19a8cd57b910ad9e3664249b13aa4903b6b1f8739cd2dbaf3", kill_on_drop: false }`
[INFO] [stderr]    Compiling pulldown-cmark v0.1.2
[INFO] [stderr]     Checking unicode-xid v0.0.4
[INFO] [stderr]     Checking percent-encoding v1.0.1
[INFO] [stderr]     Checking quote v0.3.15
[INFO] [stderr]     Checking bitflags v0.9.1
[INFO] [stderr]     Checking either v1.10.0
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]     Checking synom v0.11.3
[INFO] [stderr]     Checking semver-parser v0.7.0
[INFO] [stderr]     Checking serializers v0.2.3 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking syn v0.11.11
[INFO] [stderr]     Checking url v1.7.2
[INFO] [stderr]     Checking version-sync v0.5.0
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 5.12s
[INFO] running `Command { std: "docker" "inspect" "1de8a300dd5635a19a8cd57b910ad9e3664249b13aa4903b6b1f8739cd2dbaf3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1de8a300dd5635a19a8cd57b910ad9e3664249b13aa4903b6b1f8739cd2dbaf3", kill_on_drop: false }`
[INFO] [stdout] 1de8a300dd5635a19a8cd57b910ad9e3664249b13aa4903b6b1f8739cd2dbaf3