[INFO] crate wasm-core 0.2.15 is already in cache
[INFO] extracting crate wasm-core 0.2.15 into work/ex/beta-1.37-6/sources/1.36.0/reg/wasm-core/0.2.15
[INFO] extracting crate wasm-core 0.2.15 into work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/wasm-core/0.2.15
[INFO] validating manifest of wasm-core-0.2.15 on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of wasm-core-0.2.15 on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing wasm-core-0.2.15
[INFO] finished frobbing wasm-core-0.2.15
[INFO] frobbed toml for wasm-core-0.2.15 written to work/ex/beta-1.37-6/sources/1.36.0/reg/wasm-core/0.2.15/Cargo.toml
[INFO] started frobbing wasm-core-0.2.15
[INFO] finished frobbing wasm-core-0.2.15
[INFO] frobbed toml for wasm-core-0.2.15 written to work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/wasm-core/0.2.15/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] testing wasm-core-0.2.15 against 1.36.0 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/wasm-core/0.2.15:/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" "+1.36.0" "build" "--frozen"`
[INFO] [stdout] ac66f82826aaec7effdc55f8b2d71cc0a6524c1869c0a33e2e88dfc4bbff15c3
[INFO] running `"docker" "start" "-a" "ac66f82826aaec7effdc55f8b2d71cc0a6524c1869c0a33e2e88dfc4bbff15c3"`
[INFO] [stderr]    Compiling serde_derive v1.0.98
[INFO] [stderr]    Compiling wasm-core v0.2.15 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![feature(alloc)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![feature(nll)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:5:1
[INFO] [stderr]   |
[INFO] [stderr] 5 | #![feature(core_intrinsics)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:6:1
[INFO] [stderr]   |
[INFO] [stderr] 6 | #![feature(underscore_lifetimes)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:7:1
[INFO] [stderr]   |
[INFO] [stderr] 7 | #![feature(test)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]   --> src/lib.rs:29:1
[INFO] [stderr]    |
[INFO] [stderr] 29 | #[macro_use]
[INFO] [stderr]    | ^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `fp_ops`
[INFO] [stderr]  --> src/value.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use fp_ops;
[INFO] [stderr]   |     ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `ExecuteError`, `ExecuteResult`
[INFO] [stderr]  --> src/fp_ops.rs:1:16
[INFO] [stderr]   |
[INFO] [stderr] 1 | use executor::{ExecuteResult, ExecuteError};
[INFO] [stderr]   |                ^^^^^^^^^^^^^  ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 5 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `wasm-core`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "ac66f82826aaec7effdc55f8b2d71cc0a6524c1869c0a33e2e88dfc4bbff15c3"`
[INFO] running `"docker" "rm" "-f" "ac66f82826aaec7effdc55f8b2d71cc0a6524c1869c0a33e2e88dfc4bbff15c3"`
[INFO] [stdout] ac66f82826aaec7effdc55f8b2d71cc0a6524c1869c0a33e2e88dfc4bbff15c3