[INFO] crate semverver 0.1.39 is already in cache
[INFO] extracting crate semverver 0.1.39 into work/ex/beta-1.38-1/sources/1.37.0/reg/semverver/0.1.39
[INFO] extracting crate semverver 0.1.39 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/semverver/0.1.39
[INFO] validating manifest of semverver-0.1.39 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 semverver-0.1.39 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 semverver-0.1.39
[INFO] finished frobbing semverver-0.1.39
[INFO] frobbed toml for semverver-0.1.39 written to work/ex/beta-1.38-1/sources/1.37.0/reg/semverver/0.1.39/Cargo.toml
[INFO] started frobbing semverver-0.1.39
[INFO] finished frobbing semverver-0.1.39
[INFO] frobbed toml for semverver-0.1.39 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/semverver/0.1.39/Cargo.toml
[INFO] crate semverver-0.1.39 already has a lockfile, it will not be regenerated
[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 semverver-0.1.39 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-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/semverver/0.1.39:/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] f59e22ec501df594af8ae56bce2d7a8ff08318bd49b3c2c1fcdc2b75e4902d83
[INFO] running `"docker" "start" "-a" "f59e22ec501df594af8ae56bce2d7a8ff08318bd49b3c2c1fcdc2b75e4902d83"`
[INFO] [stderr]    Compiling curl v0.4.22
[INFO] [stderr]    Compiling rustc-workspace-hack v1.0.0
[INFO] [stderr]    Compiling semverver v0.1.39 (/opt/crater/workdir)
[INFO] [stderr]    Compiling shell-escape v0.1.4
[INFO] [stderr]    Compiling home v0.3.4
[INFO] [stderr]    Compiling libnghttp2-sys v0.1.1
[INFO] [stderr]    Compiling libz-sys v1.0.25
[INFO] [stderr]    Compiling libssh2-sys v0.2.11
[INFO] [stderr]    Compiling curl-sys v0.4.20
[INFO] [stderr]    Compiling libgit2-sys v0.7.11
[INFO] [stderr]    Compiling openssl-sys v0.9.47
[INFO] [stderr]    Compiling atty v0.2.12
[INFO] [stderr]    Compiling filetime v0.2.6
[INFO] [stderr]    Compiling fs2 v0.4.3
[INFO] [stderr]    Compiling bstr v0.2.1
[INFO] [stderr]    Compiling jobserver v0.1.14
[INFO] [stderr]    Compiling clap v2.33.0
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling tar v0.4.26
[INFO] [stderr]    Compiling env_logger v0.6.2
[INFO] [stderr]    Compiling openssl v0.10.23
[INFO] [stderr]    Compiling globset v0.4.4
[INFO] [stderr]    Compiling flate2 v1.0.9
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling serde_json v1.0.40
[INFO] [stderr]    Compiling serde_ignored v0.0.4
[INFO] [stderr]    Compiling url_serde v0.2.0
[INFO] [stderr]    Compiling failure v0.1.5
[INFO] [stderr]    Compiling tempfile v3.1.0
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling ignore v0.4.7
[INFO] [stderr]    Compiling rustfix v0.4.5
[INFO] [stderr]    Compiling im-rc v12.3.4
[INFO] [stderr]    Compiling crypto-hash v0.3.3
[INFO] [stderr]    Compiling crates-io v0.25.0
[INFO] [stderr]    Compiling crates-io v0.24.0
[INFO] [stderr]    Compiling git2 v0.8.0
[INFO] [stderr]    Compiling git2-curl v0.9.0
[INFO] [stderr]    Compiling cargo v0.37.0
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(rustc_diagnostic_macros)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(rustc_private)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `semverver`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "f59e22ec501df594af8ae56bce2d7a8ff08318bd49b3c2c1fcdc2b75e4902d83"`
[INFO] running `"docker" "rm" "-f" "f59e22ec501df594af8ae56bce2d7a8ff08318bd49b3c2c1fcdc2b75e4902d83"`
[INFO] [stdout] f59e22ec501df594af8ae56bce2d7a8ff08318bd49b3c2c1fcdc2b75e4902d83