[INFO] updating cached repository exscape/float-bug-testcase
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/exscape/float-bug-testcase
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/exscape/float-bug-testcase" "work/ex/beta-1.38-1/sources/1.37.0/gh/exscape/float-bug-testcase"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/exscape/float-bug-testcase'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/exscape/float-bug-testcase" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/exscape/float-bug-testcase"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/exscape/float-bug-testcase'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 125379c1f9663e55b2a2a44465ac4ba0f315c316
[INFO] sha for GitHub repo exscape/float-bug-testcase: 125379c1f9663e55b2a2a44465ac4ba0f315c316
[INFO] validating manifest of exscape/float-bug-testcase 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 exscape/float-bug-testcase 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 exscape/float-bug-testcase
[INFO] finished frobbing exscape/float-bug-testcase
[INFO] frobbed toml for exscape/float-bug-testcase written to work/ex/beta-1.38-1/sources/1.37.0/gh/exscape/float-bug-testcase/Cargo.toml
[INFO] started frobbing exscape/float-bug-testcase
[INFO] finished frobbing exscape/float-bug-testcase
[INFO] frobbed toml for exscape/float-bug-testcase written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/exscape/float-bug-testcase/Cargo.toml
[INFO] crate exscape/float-bug-testcase 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 exscape/float-bug-testcase 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-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/exscape/float-bug-testcase:/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] 6a812824cb7a83ea0e10bb202366feeb90f788278bbd74c2bf2f0acd91890b27
[INFO] running `"docker" "start" "-a" "6a812824cb7a83ea0e10bb202366feeb90f788278bbd74c2bf2f0acd91890b27"`
[INFO] [stderr]    Compiling float-bug-testcase v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/main.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(lang_items, unwind_attributes, asm)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: malformed `unwind` attribute input
[INFO] [stderr]   --> src/main.rs:27:5
[INFO] [stderr]    |
[INFO] [stderr] 27 |     #[unwind]
[INFO] [stderr]    |     ^^^^^^^^^ help: must be of the form: `#[unwind(allowed|aborts)]`
[INFO] [stderr] 
[INFO] [stderr] error[E0522]: definition of an unknown language item: `panic_fmt`
[INFO] [stderr]   --> src/main.rs:26:5
[INFO] [stderr]    |
[INFO] [stderr] 26 |     #[lang = "panic_fmt"]
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^ definition of unknown language item `panic_fmt`
[INFO] [stderr] 
[INFO] [stderr] error: `#[panic_handler]` function required, but not found
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 4 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0522, E0554.
[INFO] [stderr] For more information about an error, try `rustc --explain E0522`.
[INFO] [stderr] error: Could not compile `float-bug-testcase`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "6a812824cb7a83ea0e10bb202366feeb90f788278bbd74c2bf2f0acd91890b27"`
[INFO] running `"docker" "rm" "-f" "6a812824cb7a83ea0e10bb202366feeb90f788278bbd74c2bf2f0acd91890b27"`
[INFO] [stdout] 6a812824cb7a83ea0e10bb202366feeb90f788278bbd74c2bf2f0acd91890b27