[INFO] fetching crate localforage-stdweb 0.2.1...
[INFO] testing localforage-stdweb-0.2.1 against 1.90.0 for beta-1.91-3
[INFO] extracting crate localforage-stdweb 0.2.1 into /workspace/builds/worker-5-tc1/source
[INFO] started tweaking crates.io crate localforage-stdweb 0.2.1
[INFO] finished tweaking crates.io crate localforage-stdweb 0.2.1
[INFO] tweaked toml for crates.io crate localforage-stdweb 0.2.1 written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate localforage-stdweb 0.2.1 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 45 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "fetch" "--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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded futures-io-preview v0.3.0-alpha.19
[INFO] [stderr]   Downloaded futures-executor-preview v0.3.0-alpha.19
[INFO] [stderr]   Downloaded futures-preview v0.3.0-alpha.19
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 579b4aabc735c0ec2e1845b5f07c279230412b4871d52dfdb343ae5cd4321770
[INFO] running `Command { std: "docker" "start" "-a" "579b4aabc735c0ec2e1845b5f07c279230412b4871d52dfdb343ae5cd4321770", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "579b4aabc735c0ec2e1845b5f07c279230412b4871d52dfdb343ae5cd4321770", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "579b4aabc735c0ec2e1845b5f07c279230412b4871d52dfdb343ae5cd4321770", kill_on_drop: false }`
[INFO] [stdout] 579b4aabc735c0ec2e1845b5f07c279230412b4871d52dfdb343ae5cd4321770
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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=warn" "-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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b2142497f3234f8801178e5f49a08f9e498ad054ac7e8c94e30b3362cd2e9f24
[INFO] running `Command { std: "docker" "start" "-a" "b2142497f3234f8801178e5f49a08f9e498ad054ac7e8c94e30b3362cd2e9f24", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling sha1_smol v1.0.1
[INFO] [stderr]    Compiling stdweb-internal-runtime v0.1.5
[INFO] [stderr]    Compiling base-x v0.2.11
[INFO] [stderr]    Compiling discard v1.0.4
[INFO] [stderr]    Compiling syn v2.0.106
[INFO] [stderr]    Compiling num_cpus v1.17.0
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling sha1 v0.6.1
[INFO] [stderr]    Compiling stdweb v0.4.20
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling futures-executor-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling futures-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling serde_derive v1.0.228
[INFO] [stderr]    Compiling stdweb-derive v0.5.3
[INFO] [stderr]    Compiling stdweb-internal-macros v0.2.9
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/stdweb-0.4.20/src/lib.rs:117:34
[INFO] [stdout]     |
[INFO] [stdout] 117 | #![cfg_attr(feature = "nightly", feature(never_type))]
[INFO] [stdout]     |                                  ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `stdweb` (lib) due to 1 previous error; 5020 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "b2142497f3234f8801178e5f49a08f9e498ad054ac7e8c94e30b3362cd2e9f24", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b2142497f3234f8801178e5f49a08f9e498ad054ac7e8c94e30b3362cd2e9f24", kill_on_drop: false }`
[INFO] [stdout] b2142497f3234f8801178e5f49a08f9e498ad054ac7e8c94e30b3362cd2e9f24