[INFO] updating cached repository jacklund/matrix-rs
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/jacklund/matrix-rs
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/jacklund/matrix-rs" "work/ex/beta-1.38-1/sources/1.37.0/gh/jacklund/matrix-rs"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/jacklund/matrix-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/jacklund/matrix-rs" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/jacklund/matrix-rs"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/jacklund/matrix-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 86f601e3d56b33d42cb65c12a4e415f893b833cd
[INFO] sha for GitHub repo jacklund/matrix-rs: 86f601e3d56b33d42cb65c12a4e415f893b833cd
[INFO] validating manifest of jacklund/matrix-rs 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 jacklund/matrix-rs 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 jacklund/matrix-rs
[INFO] finished frobbing jacklund/matrix-rs
[INFO] frobbed toml for jacklund/matrix-rs written to work/ex/beta-1.38-1/sources/1.37.0/gh/jacklund/matrix-rs/Cargo.toml
[INFO] started frobbing jacklund/matrix-rs
[INFO] finished frobbing jacklund/matrix-rs
[INFO] frobbed toml for jacklund/matrix-rs written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/jacklund/matrix-rs/Cargo.toml
[INFO] crate jacklund/matrix-rs 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 jacklund/matrix-rs 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-0/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/jacklund/matrix-rs:/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] c541a31881f7e0367ba80f27e8c56032282bf96a50615299e41862c00e8f8fe9
[INFO] running `"docker" "start" "-a" "c541a31881f7e0367ba80f27e8c56032282bf96a50615299e41862c00e8f8fe9"`
[INFO] [stderr]    Compiling memchr v1.0.1
[INFO] [stderr]    Compiling rocket_codegen v0.1.4
[INFO] [stderr]    Compiling toml v0.2.1
[INFO] [stderr]    Compiling serde_test v0.8.21
[INFO] [stderr]    Compiling serde_derive v0.8.21
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/rocket_codegen-0.1.4/build.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(slice_patterns)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/serde_derive-0.8.21/src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(proc_macro, proc_macro_lib)]
[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: 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 `serde_derive`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: Could not compile `rocket_codegen`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "c541a31881f7e0367ba80f27e8c56032282bf96a50615299e41862c00e8f8fe9"`
[INFO] running `"docker" "rm" "-f" "c541a31881f7e0367ba80f27e8c56032282bf96a50615299e41862c00e8f8fe9"`
[INFO] [stdout] c541a31881f7e0367ba80f27e8c56032282bf96a50615299e41862c00e8f8fe9