[INFO] fetching crate rocket_contrib_codegen 0.4.2...
[INFO] extracting crate rocket_contrib_codegen 0.4.2 into work/ex/beta-1.37-6/sources/1.36.0/reg/rocket_contrib_codegen/0.4.2
[INFO] extracting crate rocket_contrib_codegen 0.4.2 into work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/rocket_contrib_codegen/0.4.2
[INFO] validating manifest of rocket_contrib_codegen-0.4.2 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 rocket_contrib_codegen-0.4.2 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 rocket_contrib_codegen-0.4.2
[INFO] finished frobbing rocket_contrib_codegen-0.4.2
[INFO] frobbed toml for rocket_contrib_codegen-0.4.2 written to work/ex/beta-1.37-6/sources/1.36.0/reg/rocket_contrib_codegen/0.4.2/Cargo.toml
[INFO] started frobbing rocket_contrib_codegen-0.4.2
[INFO] finished frobbing rocket_contrib_codegen-0.4.2
[INFO] frobbed toml for rocket_contrib_codegen-0.4.2 written to work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/rocket_contrib_codegen/0.4.2/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] testing rocket_contrib_codegen-0.4.2 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-0/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/rocket_contrib_codegen/0.4.2:/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] c568f3cf9edc42c386d32fced02639b0a5d79edf3b85a52af99f206269ba2492
[INFO] running `"docker" "start" "-a" "c568f3cf9edc42c386d32fced02639b0a5d79edf3b85a52af99f206269ba2492"`
[INFO] [stderr]    Compiling rocket_contrib_codegen v0.4.2 (/opt/crater/workdir)
[INFO] [stderr]    Compiling syn v0.15.42
[INFO] [stderr] error: failed to run custom build command for `rocket_contrib_codegen v0.4.2 (/opt/crater/workdir)`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/crater/target/debug/build/rocket_contrib_codegen-b6424b4c33df5b4b/build-script-build` (exit code: 101)
[INFO] [stderr] --- stderr
[INFO] [stderr] Error: Rocket requires a 'dev' or 'nightly' version of rustc.
[INFO] [stderr] Installed version: 1.36.0 (2019-07-03)
[INFO] [stderr] Minimum required:  1.31.0-nightly (2018-10-05)
[INFO] [stderr] See the getting started guide (https://rocket.rs/v0.5/guide/getting-started/) for more information.
[INFO] [stderr] thread 'main' panicked at 'Aborting compilation due to incompatible compiler.', build.rs:29:13
[INFO] [stderr] stack backtrace:
[INFO] [stderr]    0:     0x557c8c711b83 - std::sys::unix::backtrace::tracing::imp::unwind_backtrace::h6485381528590a55
[INFO] [stderr]                                at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:39
[INFO] [stderr]    1:     0x557c8c70d7bb - std::sys_common::backtrace::_print::h49a82ae9552e35c7
[INFO] [stderr]                                at src/libstd/sys_common/backtrace.rs:71
[INFO] [stderr]    2:     0x557c8c710a16 - std::panicking::default_hook::{{closure}}::he20974adbefcc046
[INFO] [stderr]                                at src/libstd/sys_common/backtrace.rs:59
[INFO] [stderr]                                at src/libstd/panicking.rs:197
[INFO] [stderr]    3:     0x557c8c7107a9 - std::panicking::default_hook::he4af6af4ac7fef7b
[INFO] [stderr]                                at src/libstd/panicking.rs:211
[INFO] [stderr]    4:     0x557c8c71106f - std::panicking::rust_panic_with_hook::h057ff03eb4c8000f
[INFO] [stderr]                                at src/libstd/panicking.rs:474
[INFO] [stderr]    5:     0x557c8c6e3bf3 - std::panicking::begin_panic::hf6d705021b7dac40
[INFO] [stderr]                                at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:408
[INFO] [stderr]    6:     0x557c8c6df2cb - build_script_build::main::h16d724538adbf862
[INFO] [stderr]                                at /opt/crater/workdir/build.rs:29
[INFO] [stderr]    7:     0x557c8c6e151f - std::rt::lang_start::{{closure}}::hf737e2e376351187
[INFO] [stderr]                                at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/rt.rs:64
[INFO] [stderr]    8:     0x557c8c710ac2 - std::panicking::try::do_call::hc3d8373a0b215f51
[INFO] [stderr]                                at src/libstd/rt.rs:49
[INFO] [stderr]                                at src/libstd/panicking.rs:293
[INFO] [stderr]    9:     0x557c8c716fb9 - __rust_maybe_catch_panic
[INFO] [stderr]                                at src/libpanic_unwind/lib.rs:85
[INFO] [stderr]   10:     0x557c8c71157c - std::rt::lang_start_internal::he5218c8b95d395f2
[INFO] [stderr]                                at src/libstd/panicking.rs:272
[INFO] [stderr]                                at src/libstd/panic.rs:394
[INFO] [stderr]                                at src/libstd/rt.rs:48
[INFO] [stderr]   11:     0x557c8c6e14f8 - std::rt::lang_start::h45991e43c9071224
[INFO] [stderr]                                at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/rt.rs:64
[INFO] [stderr]   12:     0x557c8c6dfa59 - main
[INFO] [stderr]   13:     0x7fd6277ba2e0 - __libc_start_main
[INFO] [stderr]   14:     0x557c8c6de9d9 - _start
[INFO] [stderr]   15:                0x0 - <unknown>
[INFO] [stderr] 
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "c568f3cf9edc42c386d32fced02639b0a5d79edf3b85a52af99f206269ba2492"`
[INFO] running `"docker" "rm" "-f" "c568f3cf9edc42c386d32fced02639b0a5d79edf3b85a52af99f206269ba2492"`
[INFO] [stdout] c568f3cf9edc42c386d32fced02639b0a5d79edf3b85a52af99f206269ba2492