[INFO] crate core_io 0.1.20190701 is already in cache
[INFO] extracting crate core_io 0.1.20190701 into work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/reg/core_io/0.1.20190701
[INFO] extracting crate core_io 0.1.20190701 into work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/reg/core_io/0.1.20190701
[INFO] validating manifest of core_io-0.1.20190701 on toolchain master#452087b4bf18cece2d52d7cd8c9147195e5404bf
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of core_io-0.1.20190701 on toolchain try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing core_io-0.1.20190701
[INFO] finished frobbing core_io-0.1.20190701
[INFO] frobbed toml for core_io-0.1.20190701 written to work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/reg/core_io/0.1.20190701/Cargo.toml
[INFO] started frobbing core_io-0.1.20190701
[INFO] finished frobbing core_io-0.1.20190701
[INFO] frobbed toml for core_io-0.1.20190701 written to work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/reg/core_io/0.1.20190701/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking core_io-0.1.20190701 against master#452087b4bf18cece2d52d7cd8c9147195e5404bf for pr-63247
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63247/worker-4/master#452087b4bf18cece2d52d7cd8c9147195e5404bf:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/reg/core_io/0.1.20190701:/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=forbid" "-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" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] fbf4a548efd09f88a3cfa9eceb8507e7474a9cc9870b00515584547a3f39eed5
[INFO] running `"docker" "start" "-a" "fbf4a548efd09f88a3cfa9eceb8507e7474a9cc9870b00515584547a3f39eed5"`
[INFO] [stderr]    Compiling core_io v0.1.20190701 (/opt/crater/workdir)
[INFO] [stderr] error: failed to run custom build command for `core_io v0.1.20190701 (/opt/crater/workdir)`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/crater/target/debug/build/core_io-fa29dca6cb3d87fa/build-script-build` (exit code: 101)
[INFO] [stderr] --- stderr
[INFO] [stderr] thread 'main' panicked at 'Unknown compiler version, upgrade core_io?', src/libcore/option.rs:1166:5
[INFO] [stderr] stack backtrace:
[INFO] [stderr]    0:     0x5632a80c76eb - backtrace::backtrace::libunwind::trace::h5d27dcba3b250cfe
[INFO] [stderr]                                at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.34/src/backtrace/libunwind.rs:88
[INFO] [stderr]    1:     0x5632a80c76eb - backtrace::backtrace::trace_unsynchronized::h239341a8b1cadbab
[INFO] [stderr]                                at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.34/src/backtrace/mod.rs:66
[INFO] [stderr]    2:     0x5632a80c76eb - std::sys_common::backtrace::_print::hb0e5dd39180a1838
[INFO] [stderr]                                at src/libstd/sys_common/backtrace.rs:47
[INFO] [stderr]    3:     0x5632a80c76eb - std::sys_common::backtrace::print::h9b385b2285f057b8
[INFO] [stderr]                                at src/libstd/sys_common/backtrace.rs:36
[INFO] [stderr]    4:     0x5632a80c76eb - std::panicking::default_hook::{{closure}}::he3310a15a78966b4
[INFO] [stderr]                                at src/libstd/panicking.rs:200
[INFO] [stderr]    5:     0x5632a80c73c6 - std::panicking::default_hook::h2986f418df62eff4
[INFO] [stderr]                                at src/libstd/panicking.rs:214
[INFO] [stderr]    6:     0x5632a80c7dad - std::panicking::rust_panic_with_hook::h15065386631d2a9d
[INFO] [stderr]                                at src/libstd/panicking.rs:477
[INFO] [stderr]    7:     0x5632a80c7932 - std::panicking::continue_panic_fmt::h5e7761875fda3864
[INFO] [stderr]                                at src/libstd/panicking.rs:384
[INFO] [stderr]    8:     0x5632a80c7816 - rust_begin_unwind
[INFO] [stderr]                                at src/libstd/panicking.rs:311
[INFO] [stderr]    9:     0x5632a80e05ed - core::panicking::panic_fmt::ha57541b4d360b196
[INFO] [stderr]                                at src/libcore/panicking.rs:85
[INFO] [stderr]   10:     0x5632a80e0657 - core::option::expect_failed::hd0b865765f7e1444
[INFO] [stderr]                                at src/libcore/option.rs:1166
[INFO] [stderr]   11:     0x5632a809a56a - core::option::Option<T>::expect::h1455260dc219108f
[INFO] [stderr]                                at /rustc/452087b4bf18cece2d52d7cd8c9147195e5404bf/src/libcore/option.rs:345
[INFO] [stderr]   12:     0x5632a809533b - build_script_build::main::h9ddb16ce234d8062
[INFO] [stderr]                                at /opt/crater/workdir/build.rs:73
[INFO] [stderr]   13:     0x5632a809aef0 - std::rt::lang_start::{{closure}}::h4008dd43d97c171d
[INFO] [stderr]                                at /rustc/452087b4bf18cece2d52d7cd8c9147195e5404bf/src/libstd/rt.rs:64
[INFO] [stderr]   14:     0x5632a80c7803 - std::rt::lang_start_internal::{{closure}}::hbf4603a1e6e1424d
[INFO] [stderr]                                at src/libstd/rt.rs:49
[INFO] [stderr]   15:     0x5632a80c7803 - std::panicking::try::do_call::h7642e0de797eeae0
[INFO] [stderr]                                at src/libstd/panicking.rs:296
[INFO] [stderr]   16:     0x5632a80cdd9a - __rust_maybe_catch_panic
[INFO] [stderr]                                at src/libpanic_unwind/lib.rs:80
[INFO] [stderr]   17:     0x5632a80c82bd - std::panicking::try::h17f145530f8b5a3f
[INFO] [stderr]                                at src/libstd/panicking.rs:275
[INFO] [stderr]   18:     0x5632a80c82bd - std::panic::catch_unwind::hcee1b9b07ea0f9dc
[INFO] [stderr]                                at src/libstd/panic.rs:394
[INFO] [stderr]   19:     0x5632a80c82bd - std::rt::lang_start_internal::h82d44298f58b2cfd
[INFO] [stderr]                                at src/libstd/rt.rs:48
[INFO] [stderr]   20:     0x5632a809aec9 - std::rt::lang_start::hdac5b88397c3fdf3
[INFO] [stderr]                                at /rustc/452087b4bf18cece2d52d7cd8c9147195e5404bf/src/libstd/rt.rs:64
[INFO] [stderr]   21:     0x5632a8095eaa - main
[INFO] [stderr]   22:     0x7fe51ca352e1 - __libc_start_main
[INFO] [stderr]   23:     0x5632a8092d1a - _start
[INFO] [stderr]   24:                0x0 - <unknown>
[INFO] [stderr] 
[INFO] running `"docker" "inspect" "fbf4a548efd09f88a3cfa9eceb8507e7474a9cc9870b00515584547a3f39eed5"`
[INFO] running `"docker" "rm" "-f" "fbf4a548efd09f88a3cfa9eceb8507e7474a9cc9870b00515584547a3f39eed5"`
[INFO] [stdout] fbf4a548efd09f88a3cfa9eceb8507e7474a9cc9870b00515584547a3f39eed5