[INFO] fetching crate zerodmg-emulator 0.1.9...
[INFO] documenting zerodmg-emulator-0.1.9 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate zerodmg-emulator 0.1.9 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate zerodmg-emulator 0.1.9 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 zerodmg-emulator 0.1.9
[INFO] finished tweaking crates.io crate zerodmg-emulator 0.1.9
[INFO] tweaked toml for crates.io crate zerodmg-emulator 0.1.9 written to /workspace/builds/worker-1/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] warning: the cargo feature `edition` is now stable and is no longer necessary to be listed in the manifest
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded zerodmg-utils v0.1.9
[INFO] [stderr]   Downloaded zerodmg-codes v0.1.9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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] da4c9d99354dac40f9a7532d0b39f16e9e4ef2dbf07d90d16b0e876727af621f
[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" "da4c9d99354dac40f9a7532d0b39f16e9e4ef2dbf07d90d16b0e876727af621f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "da4c9d99354dac40f9a7532d0b39f16e9e4ef2dbf07d90d16b0e876727af621f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da4c9d99354dac40f9a7532d0b39f16e9e4ef2dbf07d90d16b0e876727af621f", kill_on_drop: false }`
[INFO] [stdout] da4c9d99354dac40f9a7532d0b39f16e9e4ef2dbf07d90d16b0e876727af621f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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] [stdout] aee71dd33dc4555346135776c5e546e43c2cd5c094796e9745bdec54550e4eaf
[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" "aee71dd33dc4555346135776c5e546e43c2cd5c094796e9745bdec54550e4eaf", kill_on_drop: false }`
[INFO] [stderr] warning: the cargo feature `edition` is now stable and is no longer necessary to be listed in the manifest
[INFO] [stderr]    Compiling proc-macro2 v0.3.8
[INFO] [stderr]     Checking num-rational v0.1.42
[INFO] [stderr]     Checking png v0.12.0
[INFO] [stderr]    Compiling quote v0.5.2
[INFO] [stderr]     Checking image v0.19.0
[INFO] [stderr]    Compiling syn v0.13.11
[INFO] [stderr]     Checking zerodmg-utils v0.1.9
[INFO] [stderr]    Compiling derive_more v0.11.0
[INFO] [stderr]     Checking zerodmg-codes v0.1.9
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/zerodmg-codes-0.1.9/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(rust_2018_preview)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/zerodmg-codes-0.1.9/src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(rust_2018_idioms)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/zerodmg-codes-0.1.9/src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(try_from)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `zerodmg-codes`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "aee71dd33dc4555346135776c5e546e43c2cd5c094796e9745bdec54550e4eaf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aee71dd33dc4555346135776c5e546e43c2cd5c094796e9745bdec54550e4eaf", kill_on_drop: false }`
[INFO] [stdout] aee71dd33dc4555346135776c5e546e43c2cd5c094796e9745bdec54550e4eaf