[INFO] fetching crate fn_mut 0.1.0...
[INFO] testing fn_mut-0.1.0 against 1.55.0 for beta-1.56-1
[INFO] extracting crate fn_mut 0.1.0 into /workspace/builds/worker-86/source
[INFO] validating manifest of crates.io crate fn_mut 0.1.0 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate fn_mut 0.1.0
[INFO] finished tweaking crates.io crate fn_mut 0.1.0
[INFO] tweaked toml for crates.io crate fn_mut 0.1.0 written to /workspace/builds/worker-86/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a0b40c175aaefbe197cae30c45b70e92c44f2af0db575d1b186951aae82e4af2
[INFO] running `Command { std: "docker" "start" "-a" "a0b40c175aaefbe197cae30c45b70e92c44f2af0db575d1b186951aae82e4af2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a0b40c175aaefbe197cae30c45b70e92c44f2af0db575d1b186951aae82e4af2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a0b40c175aaefbe197cae30c45b70e92c44f2af0db575d1b186951aae82e4af2", kill_on_drop: false }`
[INFO] [stdout] a0b40c175aaefbe197cae30c45b70e92c44f2af0db575d1b186951aae82e4af2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] bec6f437d3e26fd6121052c1ba929dfb895c7fd33b08170102a96f01f5717cab
[INFO] running `Command { std: "docker" "start" "-a" "bec6f437d3e26fd6121052c1ba929dfb895c7fd33b08170102a96f01f5717cab", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]    Compiling unicode-xid v0.0.4
[INFO] [stderr]    Compiling ucd-util v0.1.8
[INFO] [stderr]    Compiling quote v0.3.15
[INFO] [stderr]    Compiling utf8-ranges v1.0.4
[INFO] [stderr]    Compiling lazy_static v0.2.11
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]    Compiling aho-corasick v0.6.10
[INFO] [stderr]    Compiling regex-syntax v0.5.6
[INFO] [stderr]    Compiling synom v0.11.3
[INFO] [stderr]    Compiling syn v0.11.11
[INFO] [stderr]    Compiling fn_mut 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:67:1
[INFO] [stdout]    |
[INFO] [stdout] 67 | #![feature(proc_macro)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]    |
[INFO] [stdout]    = help: the feature `proc_macro` has been stable since 1.29.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated constant `std::sync::ONCE_INIT`: the `new` function is now preferred
[INFO] [stdout]   --> src/config.rs:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | / lazy_static! {
[INFO] [stdout] 11 | |     static ref RE1: Regex = Regex::new(r#"([a-zA-Z0-9_]+)( = "([a-zA-Z0-9,_]*)")?"#).unwrap();
[INFO] [stdout] 12 | |     static ref RE2: Regex = Regex::new(r#"[a-zA-Z0-9_]*"#).unwrap();
[INFO] [stdout] 13 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `__lazy_static_create` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated constant `std::sync::ONCE_INIT`: the `new` function is now preferred
[INFO] [stdout]   --> src/config.rs:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | / lazy_static! {
[INFO] [stdout] 11 | |     static ref RE1: Regex = Regex::new(r#"([a-zA-Z0-9_]+)( = "([a-zA-Z0-9,_]*)")?"#).unwrap();
[INFO] [stdout] 12 | |     static ref RE2: Regex = Regex::new(r#"[a-zA-Z0-9_]*"#).unwrap();
[INFO] [stdout] 13 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `__lazy_static_create` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `fn_mut` due to 2 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "bec6f437d3e26fd6121052c1ba929dfb895c7fd33b08170102a96f01f5717cab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bec6f437d3e26fd6121052c1ba929dfb895c7fd33b08170102a96f01f5717cab", kill_on_drop: false }`
[INFO] [stdout] bec6f437d3e26fd6121052c1ba929dfb895c7fd33b08170102a96f01f5717cab