[INFO] crate overloadable 0.4.1 is already in cache
[INFO] testing overloadable-0.4.1 against 1.38.0 for beta-1.39-1
[INFO] extracting crate overloadable 0.4.1 into work/builds/worker-10/source
[INFO] validating manifest of crates.io crate overloadable 0.4.1 on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate overloadable 0.4.1
[INFO] finished tweaking crates.io crate overloadable 0.4.1
[INFO] tweaked toml for crates.io crate overloadable 0.4.1 written to work/builds/worker-10/source/Cargo.toml
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-10/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] d03fcc92e7b08f30fc100a5b715d1ef948fd4c91af547b0d5648b33b14d01894
[INFO] running `"docker" "start" "-a" "d03fcc92e7b08f30fc100a5b715d1ef948fd4c91af547b0d5648b33b14d01894"`
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling overloadable v0.4.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 10.10s
[INFO] running `"docker" "inspect" "d03fcc92e7b08f30fc100a5b715d1ef948fd4c91af547b0d5648b33b14d01894"`
[INFO] running `"docker" "rm" "-f" "d03fcc92e7b08f30fc100a5b715d1ef948fd4c91af547b0d5648b33b14d01894"`
[INFO] [stdout] d03fcc92e7b08f30fc100a5b715d1ef948fd4c91af547b0d5648b33b14d01894
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-10/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] c0d4b03b3a9d408829a11a8f7c4fca46a9307319976f73db8dd417bda32f7a0a
[INFO] running `"docker" "start" "-a" "c0d4b03b3a9d408829a11a8f7c4fca46a9307319976f73db8dd417bda32f7a0a"`
[INFO] [stderr]    Compiling overloadable v0.4.1 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> tests/default.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(unboxed_closures, fn_traits)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `overloadable`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "c0d4b03b3a9d408829a11a8f7c4fca46a9307319976f73db8dd417bda32f7a0a"`
[INFO] running `"docker" "rm" "-f" "c0d4b03b3a9d408829a11a8f7c4fca46a9307319976f73db8dd417bda32f7a0a"`
[INFO] [stdout] c0d4b03b3a9d408829a11a8f7c4fca46a9307319976f73db8dd417bda32f7a0a