[INFO] crate rustcov 0.0.0 is already in cache
[INFO] extracting crate rustcov 0.0.0 into work/ex/beta-1.38-1/sources/1.37.0/reg/rustcov/0.0.0
[INFO] extracting crate rustcov 0.0.0 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/rustcov/0.0.0
[INFO] validating manifest of rustcov-0.0.0 on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of rustcov-0.0.0 on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing rustcov-0.0.0
[INFO] finished frobbing rustcov-0.0.0
[INFO] frobbed toml for rustcov-0.0.0 written to work/ex/beta-1.38-1/sources/1.37.0/reg/rustcov/0.0.0/Cargo.toml
[INFO] started frobbing rustcov-0.0.0
[INFO] finished frobbing rustcov-0.0.0
[INFO] frobbed toml for rustcov-0.0.0 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/rustcov/0.0.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing rustcov-0.0.0 against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-7/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/rustcov/0.0.0:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 3d38de7a6b9cf16ac9a688dc7c4df63df801fff194166a00fe7f44a42cbe7b9c
[INFO] running `"docker" "start" "-a" "3d38de7a6b9cf16ac9a688dc7c4df63df801fff194166a00fe7f44a42cbe7b9c"`
[INFO] [stderr]    Compiling rustcov v0.0.0 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.10s
[INFO] running `"docker" "inspect" "3d38de7a6b9cf16ac9a688dc7c4df63df801fff194166a00fe7f44a42cbe7b9c"`
[INFO] running `"docker" "rm" "-f" "3d38de7a6b9cf16ac9a688dc7c4df63df801fff194166a00fe7f44a42cbe7b9c"`
[INFO] [stdout] 3d38de7a6b9cf16ac9a688dc7c4df63df801fff194166a00fe7f44a42cbe7b9c
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-7/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/rustcov/0.0.0:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] e843b0e580edcb552f913f212a818d3aa4b2fb002fa20658c303038eea3732bb
[INFO] running `"docker" "start" "-a" "e843b0e580edcb552f913f212a818d3aa4b2fb002fa20658c303038eea3732bb"`
[INFO] [stderr]    Compiling rustcov v0.0.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0457]: plugin `rustcov` only found in rlib format, but must be available in dylib format
[INFO] [stderr]  --> examples/plugin.rs:2:11
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![plugin(rustcov)]
[INFO] [stderr]   |           ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> examples/plugin.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(plugin)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0601]: `main` function not found in crate `plugin`
[INFO] [stderr]   |
[INFO] [stderr]   = note: consider adding a `main` function to `examples/plugin.rs`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0554, E0601.
[INFO] [stderr] For more information about an error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `rustcov`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "e843b0e580edcb552f913f212a818d3aa4b2fb002fa20658c303038eea3732bb"`
[INFO] running `"docker" "rm" "-f" "e843b0e580edcb552f913f212a818d3aa4b2fb002fa20658c303038eea3732bb"`
[INFO] [stdout] e843b0e580edcb552f913f212a818d3aa4b2fb002fa20658c303038eea3732bb