[INFO] fetching crate megafb 0.0.1...
[INFO] documenting megafb-0.0.1 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate megafb 0.0.1 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate megafb 0.0.1 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate megafb 0.0.1
[INFO] finished tweaking crates.io crate megafb 0.0.1
[INFO] tweaked toml for crates.io crate megafb 0.0.1 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate crates.io crate megafb 0.0.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.46.0" "metadata" "--no-deps" "--format-version=1", 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] ff40d009e26ba5895d6a7679b867afa2edcfe0685606f72003f5d3b98f10bfd2
[INFO] running `Command { std: "docker" "start" "-a" "ff40d009e26ba5895d6a7679b867afa2edcfe0685606f72003f5d3b98f10bfd2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ff40d009e26ba5895d6a7679b867afa2edcfe0685606f72003f5d3b98f10bfd2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ff40d009e26ba5895d6a7679b867afa2edcfe0685606f72003f5d3b98f10bfd2", kill_on_drop: false }`
[INFO] [stdout] ff40d009e26ba5895d6a7679b867afa2edcfe0685606f72003f5d3b98f10bfd2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 66ce3c1afe45b312198a4c6bbc7fabf6be574d0121f70a011a7504d19b81df07
[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" "66ce3c1afe45b312198a4c6bbc7fabf6be574d0121f70a011a7504d19b81df07", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.60
[INFO] [stderr]    Compiling log v0.4.7
[INFO] [stderr]    Compiling syn v0.15.40
[INFO] [stderr]    Compiling arrayvec v0.4.11
[INFO] [stderr]     Checking downcast-rs v1.0.4
[INFO] [stderr]     Checking xml-rs v0.8.0
[INFO] [stderr]     Checking rustc-demangle v0.1.15
[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 libloading v0.5.2
[INFO] [stderr]    Compiling backtrace-sys v0.1.31
[INFO] [stderr]    Compiling cmake v0.1.40
[INFO] [stderr]    Compiling x11-dl v2.18.3
[INFO] [stderr]     Checking lock_api v0.2.0
[INFO] [stderr]     Checking stb_truetype v0.2.6
[INFO] [stderr]     Checking fxhash v0.2.1
[INFO] [stderr]    Compiling parking_lot_core v0.5.0
[INFO] [stderr]    Compiling parking_lot v0.8.0
[INFO] [stderr]     Checking approx v0.3.2
[INFO] [stderr]     Checking ordered-float v1.0.2
[INFO] [stderr]     Checking line_drawing v0.7.0
[INFO] [stderr]    Compiling wayland-scanner v0.23.5
[INFO] [stderr]    Compiling shaderc-sys v0.6.0
[INFO] [stderr]     Checking dlib v0.4.1
[INFO] [stderr]     Checking wayland-sys v0.23.5
[INFO] [stderr]     Checking rusttype v0.7.7
[INFO] [stderr]     Checking iovec v0.1.2
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking nix v0.14.1
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking memmap v0.7.0
[INFO] [stderr]     Checking backtrace v0.3.33
[INFO] [stderr]     Checking mio v0.6.19
[INFO] [stderr]     Checking andrew v0.2.1
[INFO] [stderr]     Checking mio-extras v2.0.5
[INFO] [stderr]    Compiling wayland-client v0.23.5
[INFO] [stderr]    Compiling wayland-protocols v0.23.5
[INFO] [stderr] error: could not compile `syn`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustc --crate-name syn /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/syn-0.15.40/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="full"' --cfg 'feature="parsing"' --cfg 'feature="printing"' --cfg 'feature="proc-macro"' --cfg 'feature="quote"' --cfg 'feature="visit"' -C metadata=a5a3289c8ac95cd9 -C extra-filename=-a5a3289c8ac95cd9 --out-dir /opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-e8a62c57741ef4cc.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-b602621ca95ec466.rmeta --extern unicode_xid=/opt/rustwide/target/debug/deps/libunicode_xid-8e68d9b5a310dbdb.rmeta --cap-lints allow --cfg syn_can_match_trailing_dollar --cfg syn_can_use_thread_id --cfg syn_can_use_associated_constants --cfg syn_can_call_macro_by_path --cfg syn_disable_nightly_tests` (signal: 9, SIGKILL: kill)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] The following warnings were emitted during compilation:
[INFO] [stderr] 
[INFO] [stderr] warning: Checking for system installed libraries.  Use --features = build-from-source to disable this behavior
[INFO] [stderr] warning: Pre-built library not found.  Falling back to from-source build
[INFO] [stderr] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "66ce3c1afe45b312198a4c6bbc7fabf6be574d0121f70a011a7504d19b81df07", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "66ce3c1afe45b312198a4c6bbc7fabf6be574d0121f70a011a7504d19b81df07", kill_on_drop: false }`
[INFO] [stdout] 66ce3c1afe45b312198a4c6bbc7fabf6be574d0121f70a011a7504d19b81df07