[INFO] crate flutter-engine 0.3.3 is already in cache
[INFO] extracting crate flutter-engine 0.3.3 into work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/reg/flutter-engine/0.3.3
[INFO] extracting crate flutter-engine 0.3.3 into work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/reg/flutter-engine/0.3.3
[INFO] validating manifest of flutter-engine-0.3.3 on toolchain master#c43d03a19f326f4a323569328cc501e86eb6d22e
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c43d03a19f326f4a323569328cc501e86eb6d22e-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of flutter-engine-0.3.3 on toolchain try#75eff020d0923c035c2fe220db4a0465cd847048
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+75eff020d0923c035c2fe220db4a0465cd847048-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing flutter-engine-0.3.3
[INFO] finished frobbing flutter-engine-0.3.3
[INFO] frobbed toml for flutter-engine-0.3.3 written to work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/reg/flutter-engine/0.3.3/Cargo.toml
[INFO] started frobbing flutter-engine-0.3.3
[INFO] finished frobbing flutter-engine-0.3.3
[INFO] frobbed toml for flutter-engine-0.3.3 written to work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/reg/flutter-engine/0.3.3/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c43d03a19f326f4a323569328cc501e86eb6d22e-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+75eff020d0923c035c2fe220db4a0465cd847048-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c43d03a19f326f4a323569328cc501e86eb6d22e-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+75eff020d0923c035c2fe220db4a0465cd847048-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking flutter-engine-0.3.3 against try#75eff020d0923c035c2fe220db4a0465cd847048 for pr-63565
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63565/worker-1/try#75eff020d0923c035c2fe220db4a0465cd847048:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/reg/flutter-engine/0.3.3:/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" "+75eff020d0923c035c2fe220db4a0465cd847048-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 82cc9c817de7f5ba780fa315e1bdef188579e99d4e02a12947b2af2000ba58d5
[INFO] running `"docker" "start" "-a" "82cc9c817de7f5ba780fa315e1bdef188579e99d4e02a12947b2af2000ba58d5"`
[INFO] [stderr]    Compiling curl v0.4.23
[INFO] [stderr]    Compiling transformation-pipeline v0.1.0
[INFO] [stderr]    Compiling libnghttp2-sys v0.1.2
[INFO] [stderr]    Compiling curl-sys v0.4.21
[INFO] [stderr]     Checking glfw v0.28.0
[INFO] [stderr]    Compiling unzip v0.1.0
[INFO] [stderr]    Compiling flutter-download v0.3.0
[INFO] [stderr]    Compiling flutter-engine-sys v0.3.4
[INFO] [stderr] error: failed to run custom build command for `flutter-engine-sys v0.3.4`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/crater/target/debug/build/flutter-engine-sys-2592196cea502586/build-script-build` (exit code: 101)
[INFO] [stderr] --- stderr
[INFO] [stderr] error: 'rustfmt' is not installed for the toolchain '75eff020d0923c035c2fe220db4a0465cd847048-alt'
[INFO] [stderr] To install, run `rustup component add rustfmt --toolchain 75eff020d0923c035c2fe220db4a0465cd847048-alt`
[INFO] [stderr] Custom { kind: Other, error: "Internal rustfmt error" }
[INFO] [stderr] thread 'main' panicked at 'Cannot get flutter engine version: InvalidFlutterRoot("output empty")', src/libcore/result.rs:1084:5
[INFO] [stderr] stack backtrace:
[INFO] [stderr]    0:     0x5577f5b6d84b - backtrace::backtrace::libunwind::trace::h223ecf9e25ea61ed
[INFO] [stderr]                                at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.34/src/backtrace/libunwind.rs:88
[INFO] [stderr]    1:     0x5577f5b6d84b - backtrace::backtrace::trace_unsynchronized::h19c402a6233e597e
[INFO] [stderr]                                at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.34/src/backtrace/mod.rs:66
[INFO] [stderr]    2:     0x5577f5b6d84b - std::sys_common::backtrace::_print::h14947081e8315ba5
[INFO] [stderr]                                at src/libstd/sys_common/backtrace.rs:47
[INFO] [stderr]    3:     0x5577f5b6d84b - std::sys_common::backtrace::print::h87cad3f0b50b59c5
[INFO] [stderr]                                at src/libstd/sys_common/backtrace.rs:36
[INFO] [stderr]    4:     0x5577f5b6d84b - std::panicking::default_hook::{{closure}}::h497a714df189bd9d
[INFO] [stderr]                                at src/libstd/panicking.rs:200
[INFO] [stderr]    5:     0x5577f5b6d526 - std::panicking::default_hook::h8dc4a117b759bd96
[INFO] [stderr]                                at src/libstd/panicking.rs:214
[INFO] [stderr]    6:     0x5577f5b6dfbd - std::panicking::rust_panic_with_hook::h4cbf0f096b75f262
[INFO] [stderr]                                at src/libstd/panicking.rs:477
[INFO] [stderr]    7:     0x5577f5b6db42 - std::panicking::continue_panic_fmt::hbfbfc57925685348
[INFO] [stderr]                                at src/libstd/panicking.rs:384
[INFO] [stderr]    8:     0x5577f5b6da26 - rust_begin_unwind
[INFO] [stderr]                                at src/libstd/panicking.rs:311
[INFO] [stderr]    9:     0x5577f5b8e59d - core::panicking::panic_fmt::h011c5c8794bf0cc5
[INFO] [stderr]                                at src/libcore/panicking.rs:85
[INFO] [stderr]   10:     0x5577f5b8e697 - core::result::unwrap_failed::hcd7c37294cdf213e
[INFO] [stderr]                                at src/libcore/result.rs:1084
[INFO] [stderr]   11:     0x5577f538b702 - core::result::Result<T,E>::expect::h3cca29b49d229573
[INFO] [stderr]                                at /rustc/75eff020d0923c035c2fe220db4a0465cd847048/src/libcore/result.rs:879
[INFO] [stderr]   12:     0x5577f5387d2b - build_script_build::main::h007e6e8d0ca03e7c
[INFO] [stderr]                                at /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/flutter-engine-sys-0.3.4/build.rs:53
[INFO] [stderr]   13:     0x5577f5383f60 - std::rt::lang_start::{{closure}}::hfd9c0a9a910edbbd
[INFO] [stderr]                                at /rustc/75eff020d0923c035c2fe220db4a0465cd847048/src/libstd/rt.rs:64
[INFO] [stderr]   14:     0x5577f5b6d9c3 - std::rt::lang_start_internal::{{closure}}::hb2a68345cd4d50f8
[INFO] [stderr]                                at src/libstd/rt.rs:49
[INFO] [stderr]   15:     0x5577f5b6d9c3 - std::panicking::try::do_call::ha4d88255f4a68d08
[INFO] [stderr]                                at src/libstd/panicking.rs:296
[INFO] [stderr]   16:     0x5577f5b7686a - __rust_maybe_catch_panic
[INFO] [stderr]                                at src/libpanic_unwind/lib.rs:80
[INFO] [stderr]   17:     0x5577f5b6e58d - std::panicking::try::h6debac9988c5415d
[INFO] [stderr]                                at src/libstd/panicking.rs:275
[INFO] [stderr]   18:     0x5577f5b6e58d - std::panic::catch_unwind::h4659dbf6316a9c8d
[INFO] [stderr]                                at src/libstd/panic.rs:394
[INFO] [stderr]   19:     0x5577f5b6e58d - std::rt::lang_start_internal::hdadab8536edf34fe
[INFO] [stderr]                                at src/libstd/rt.rs:48
[INFO] [stderr]   20:     0x5577f5383f39 - std::rt::lang_start::hc877821c15c2770e
[INFO] [stderr]                                at /rustc/75eff020d0923c035c2fe220db4a0465cd847048/src/libstd/rt.rs:64
[INFO] [stderr]   21:     0x5577f5388d1a - main
[INFO] [stderr]   22:     0x7fc30f2282e1 - __libc_start_main
[INFO] [stderr]   23:     0x5577f538089a - _start
[INFO] [stderr]   24:                0x0 - <unknown>
[INFO] [stderr] 
[INFO] running `"docker" "inspect" "82cc9c817de7f5ba780fa315e1bdef188579e99d4e02a12947b2af2000ba58d5"`
[INFO] running `"docker" "rm" "-f" "82cc9c817de7f5ba780fa315e1bdef188579e99d4e02a12947b2af2000ba58d5"`
[INFO] [stdout] 82cc9c817de7f5ba780fa315e1bdef188579e99d4e02a12947b2af2000ba58d5