[INFO] crate proptest-derive 0.1.2 is already in cache
[INFO] extracting crate proptest-derive 0.1.2 into work/ex/beta-1.38-1/sources/1.37.0/reg/proptest-derive/0.1.2
[INFO] extracting crate proptest-derive 0.1.2 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/proptest-derive/0.1.2
[INFO] validating manifest of proptest-derive-0.1.2 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 proptest-derive-0.1.2 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 proptest-derive-0.1.2
[INFO] finished frobbing proptest-derive-0.1.2
[INFO] frobbed toml for proptest-derive-0.1.2 written to work/ex/beta-1.38-1/sources/1.37.0/reg/proptest-derive/0.1.2/Cargo.toml
[INFO] started frobbing proptest-derive-0.1.2
[INFO] finished frobbing proptest-derive-0.1.2
[INFO] frobbed toml for proptest-derive-0.1.2 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/proptest-derive/0.1.2/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] [stderr]     Blocking waiting for file lock on package cache
[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 proptest-derive-0.1.2 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-4/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/proptest-derive/0.1.2:/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] e1868963e2fd85f3551a4059ffec4bb516e5888dfe0770626fc88f208046ca46
[INFO] running `"docker" "start" "-a" "e1868963e2fd85f3551a4059ffec4bb516e5888dfe0770626fc88f208046ca46"`
[INFO] [stderr]    Compiling proptest-derive v0.1.2 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.92s
[INFO] running `"docker" "inspect" "e1868963e2fd85f3551a4059ffec4bb516e5888dfe0770626fc88f208046ca46"`
[INFO] running `"docker" "rm" "-f" "e1868963e2fd85f3551a4059ffec4bb516e5888dfe0770626fc88f208046ca46"`
[INFO] [stdout] e1868963e2fd85f3551a4059ffec4bb516e5888dfe0770626fc88f208046ca46
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-4/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/proptest-derive/0.1.2:/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] 373e107eee6273d702b74934127260d6dcf6dbcfc561ac66033c1223d1db5d68
[INFO] running `"docker" "start" "-a" "373e107eee6273d702b74934127260d6dcf6dbcfc561ac66033c1223d1db5d68"`
[INFO] [stderr]    Compiling compiletest_rs v0.3.22
[INFO] [stderr]    Compiling tester v0.5.0
[INFO] [stderr]    Compiling aho-corasick v0.7.6
[INFO] [stderr]    Compiling bstr v0.2.7
[INFO] [stderr]    Compiling tinytemplate v1.0.2
[INFO] [stderr]    Compiling rustfix v0.4.6
[INFO] [stderr]    Compiling csv v1.1.1
[INFO] [stderr]    Compiling regex v1.2.1
[INFO] [stderr]    Compiling criterion v0.2.11
[INFO] [stderr]    Compiling proptest-derive v0.1.2 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> tests/enum.rs:9:1
[INFO] [stderr]   |
[INFO] [stderr] 9 | #![feature(never_type)]
[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 `proptest-derive`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "373e107eee6273d702b74934127260d6dcf6dbcfc561ac66033c1223d1db5d68"`
[INFO] running `"docker" "rm" "-f" "373e107eee6273d702b74934127260d6dcf6dbcfc561ac66033c1223d1db5d68"`
[INFO] [stdout] 373e107eee6273d702b74934127260d6dcf6dbcfc561ac66033c1223d1db5d68