[INFO] crate sexpr 0.1.0 is already in cache
[INFO] extracting crate sexpr 0.1.0 into work/ex/beta-1.38-1/sources/1.37.0/reg/sexpr/0.1.0
[INFO] extracting crate sexpr 0.1.0 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/sexpr/0.1.0
[INFO] validating manifest of sexpr-0.1.0 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 sexpr-0.1.0 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 sexpr-0.1.0
[INFO] finished frobbing sexpr-0.1.0
[INFO] frobbed toml for sexpr-0.1.0 written to work/ex/beta-1.38-1/sources/1.37.0/reg/sexpr/0.1.0/Cargo.toml
[INFO] started frobbing sexpr-0.1.0
[INFO] finished frobbing sexpr-0.1.0
[INFO] frobbed toml for sexpr-0.1.0 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/sexpr/0.1.0/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 sexpr-0.1.0 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/sexpr/0.1.0:/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] 6fbb04ae067e813cfce40cae9f8b99a11046b3d630c439ed4efed504c3da707f
[INFO] running `"docker" "start" "-a" "6fbb04ae067e813cfce40cae9f8b99a11046b3d630c439ed4efed504c3da707f"`
[INFO] [stderr]    Compiling gc v0.2.1
[INFO] [stderr]    Compiling syn v0.10.8
[INFO] [stderr] error[E0432]: unresolved import `core::nonzero`
[INFO] [stderr]   --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/gc-0.2.1/src/lib.rs:11:11
[INFO] [stderr]    |
[INFO] [stderr] 11 | use core::nonzero::NonZero;
[INFO] [stderr]    |           ^^^^^^^ could not find `nonzero` in `core`
[INFO] [stderr] 
[INFO] [stderr] error[E0432]: unresolved import `std::ptr::Shared`
[INFO] [stderr]  --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/gc-0.2.1/src/gc.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::ptr::Shared;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^ no `Shared` in `ptr`
[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/gc-0.2.1/src/lib.rs:7:1
[INFO] [stderr]   |
[INFO] [stderr] 7 | #![feature(coerce_unsized, core_intrinsics, nonzero, optin_builtin_traits, shared, unsize, specialization)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0374]: the trait `CoerceUnsized` may only be implemented for a coercion between structures with one field being coerced, none found
[INFO] [stderr]   --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/gc-0.2.1/src/lib.rs:45:1
[INFO] [stderr]    |
[INFO] [stderr] 45 | impl<T: Trace + ?Sized + marker::Unsize<U>, U: Trace + ?Sized> CoerceUnsized<Gc<U>> for Gc<T> {}
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 4 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0374, E0432, E0554.
[INFO] [stderr] For more information about an error, try `rustc --explain E0374`.
[INFO] [stderr] error: Could not compile `gc`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "6fbb04ae067e813cfce40cae9f8b99a11046b3d630c439ed4efed504c3da707f"`
[INFO] running `"docker" "rm" "-f" "6fbb04ae067e813cfce40cae9f8b99a11046b3d630c439ed4efed504c3da707f"`
[INFO] [stdout] 6fbb04ae067e813cfce40cae9f8b99a11046b3d630c439ed4efed504c3da707f