[INFO] cloning repository https://github.com/inq/denture
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/inq/denture" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Finq%2Fdenture", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Finq%2Fdenture'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ea350122271095a666dc44bef8ca9e510d97500f
[INFO] testing inq/denture against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Finq%2Fdenture" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/inq/denture on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/inq/denture
[INFO] finished tweaking git repo https://github.com/inq/denture
[INFO] tweaked toml for git repo https://github.com/inq/denture written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/inq/denture already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 01225b8ece6bf7ef6880e9b4e7479b2da9afecefea158227f80b51e4d1adc338
[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" "01225b8ece6bf7ef6880e9b4e7479b2da9afecefea158227f80b51e4d1adc338", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "01225b8ece6bf7ef6880e9b4e7479b2da9afecefea158227f80b51e4d1adc338", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "01225b8ece6bf7ef6880e9b4e7479b2da9afecefea158227f80b51e4d1adc338", kill_on_drop: false }`
[INFO] [stdout] 01225b8ece6bf7ef6880e9b4e7479b2da9afecefea158227f80b51e4d1adc338
[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" "RUSTFLAGS=--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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5b6c477584d97002b787fa74c09e8ca10ffebe822014cad0e35458fa5921d40c
[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" "5b6c477584d97002b787fa74c09e8ca10ffebe822014cad0e35458fa5921d40c", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.13
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.22
[INFO] [stderr]    Compiling libc v0.2.70
[INFO] [stderr]    Compiling gimli v0.21.0
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling object v0.19.0
[INFO] [stderr]    Compiling rustc-demangle v0.1.16
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling quote v1.0.6
[INFO] [stderr]    Compiling addr2line v0.12.0
[INFO] [stderr]    Compiling backtrace v0.3.48
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]    Compiling failure v0.1.8
[INFO] [stderr]    Compiling denture v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(bindings_after_at, or_patterns)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `denture`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "5b6c477584d97002b787fa74c09e8ca10ffebe822014cad0e35458fa5921d40c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5b6c477584d97002b787fa74c09e8ca10ffebe822014cad0e35458fa5921d40c", kill_on_drop: false }`
[INFO] [stdout] 5b6c477584d97002b787fa74c09e8ca10ffebe822014cad0e35458fa5921d40c