[INFO] fetching crate salmon 0.5.0...
[INFO] documenting salmon-0.5.0 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate salmon 0.5.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate salmon 0.5.0 on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate salmon 0.5.0
[INFO] finished tweaking crates.io crate salmon 0.5.0
[INFO] tweaked toml for crates.io crate salmon 0.5.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded ego-tree v0.6.2
[INFO] [stderr]   Downloaded scraper v0.10.1
[INFO] [stderr]   Downloaded syntect v3.3.0
[INFO] [stderr]   Downloaded sass-rs v0.2.2
[INFO] [stderr]   Downloaded selectors v0.21.0
[INFO] [stderr]   Downloaded cssparser-macros v0.3.6
[INFO] [stderr]   Downloaded cssparser v0.25.9
[INFO] [stderr]   Downloaded procedural-masquerade v0.1.7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0577c0be212a7cc6afb49e9cfb25d3e98f643dbcad6dacdb77ba8d96a2b73fff
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "0577c0be212a7cc6afb49e9cfb25d3e98f643dbcad6dacdb77ba8d96a2b73fff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0577c0be212a7cc6afb49e9cfb25d3e98f643dbcad6dacdb77ba8d96a2b73fff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0577c0be212a7cc6afb49e9cfb25d3e98f643dbcad6dacdb77ba8d96a2b73fff", kill_on_drop: false }`
[INFO] [stdout] 0577c0be212a7cc6afb49e9cfb25d3e98f643dbcad6dacdb77ba8d96a2b73fff
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "RUSTDOCFLAGS=--cap-lints=warn" "-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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c0334582ece0c777bc05dcb76d93f44932db3972e57df0218a8bd30a181eafe8
[INFO] running `Command { std: "docker" "start" "-a" "c0334582ece0c777bc05dcb76d93f44932db3972e57df0218a8bd30a181eafe8", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling siphasher v0.2.3
[INFO] [stderr]    Compiling string_cache_shared v0.3.0
[INFO] [stderr]    Compiling bindgen v0.53.3
[INFO] [stderr]    Compiling lazycell v1.3.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling itoa v0.4.6
[INFO] [stderr]     Checking new_debug_unreachable v1.0.4
[INFO] [stderr]     Checking dtoa v0.4.6
[INFO] [stderr]     Checking quick-error v1.2.3
[INFO] [stderr]     Checking mac v0.1.1
[INFO] [stderr]     Checking precomputed-hash v0.1.1
[INFO] [stderr]    Compiling procedural-masquerade v0.1.7
[INFO] [stderr]     Checking utf-8 v0.7.5
[INFO] [stderr]     Checking linked-hash-map v0.5.3
[INFO] [stderr]     Checking nodrop v0.1.14
[INFO] [stderr]     Checking safemem v0.3.3
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling pulldown-cmark v0.5.3
[INFO] [stderr]     Checking thin-slice v0.1.1
[INFO] [stderr]     Checking ego-tree v0.6.2
[INFO] [stderr]     Checking termcolor v1.1.0
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling nom v5.1.2
[INFO] [stderr]    Compiling clang-sys v0.29.3
[INFO] [stderr]     Checking getopts v0.2.21
[INFO] [stderr]     Checking phf_shared v0.7.24
[INFO] [stderr]     Checking futf v0.1.4
[INFO] [stderr]     Checking humantime v1.3.0
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand_jitter v0.1.4
[INFO] [stderr]     Checking servo_arc v0.1.1
[INFO] [stderr]     Checking line-wrap v0.1.1
[INFO] [stderr]     Checking dtoa-short v0.3.2
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]     Checking yaml-rust v0.4.4
[INFO] [stderr]     Checking phf v0.7.24
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]     Checking fxhash v0.2.1
[INFO] [stderr]     Checking base64 v0.10.1
[INFO] [stderr]     Checking flate2 v1.0.17
[INFO] [stderr]     Checking tendril v0.4.1
[INFO] [stderr]    Compiling env_logger v0.7.1
[INFO] [stderr]     Checking env_logger v0.6.2
[INFO] [stderr]    Compiling sass-sys v0.4.21
[INFO] [stderr] error: could not compile `syn`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustc --crate-name syn --edition=2018 /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/syn-1.0.39/src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts --crate-type lib --emit=dep-info,metadata,link -Cembed-bitcode=no -C debuginfo=2 --cfg 'feature="clone-impls"' --cfg 'feature="default"' --cfg 'feature="derive"' --cfg 'feature="extra-traits"' --cfg 'feature="fold"' --cfg 'feature="full"' --cfg 'feature="parsing"' --cfg 'feature="printing"' --cfg 'feature="proc-macro"' --cfg 'feature="quote"' --cfg 'feature="visit"' -C metadata=23f7f100e6479d56 -C extra-filename=-23f7f100e6479d56 --out-dir /opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-71c5aa24984e0547.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-86659819dd43cd20.rmeta --extern unicode_xid=/opt/rustwide/target/debug/deps/libunicode_xid-b888af50774a486c.rmeta --cap-lints allow --cfg syn_disable_nightly_tests` (signal: 9, SIGKILL: kill)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "c0334582ece0c777bc05dcb76d93f44932db3972e57df0218a8bd30a181eafe8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c0334582ece0c777bc05dcb76d93f44932db3972e57df0218a8bd30a181eafe8", kill_on_drop: false }`
[INFO] [stdout] c0334582ece0c777bc05dcb76d93f44932db3972e57df0218a8bd30a181eafe8