[INFO] crate serde_tuple 0.2.5 is already in cache
[INFO] extracting crate serde_tuple 0.2.5 into work/ex/beta-1.38-1/sources/1.37.0/reg/serde_tuple/0.2.5
[INFO] extracting crate serde_tuple 0.2.5 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/serde_tuple/0.2.5
[INFO] validating manifest of serde_tuple-0.2.5 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 serde_tuple-0.2.5 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 serde_tuple-0.2.5
[INFO] finished frobbing serde_tuple-0.2.5
[INFO] frobbed toml for serde_tuple-0.2.5 written to work/ex/beta-1.38-1/sources/1.37.0/reg/serde_tuple/0.2.5/Cargo.toml
[INFO] started frobbing serde_tuple-0.2.5
[INFO] finished frobbing serde_tuple-0.2.5
[INFO] frobbed toml for serde_tuple-0.2.5 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/serde_tuple/0.2.5/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing serde_tuple-0.2.5 against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/serde_tuple/0.2.5:/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" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] 4dd39d9e1864675be905ac4c0568d3dc8834f15a9636f41fec11ab67724139af
[INFO] running `"docker" "start" "-a" "4dd39d9e1864675be905ac4c0568d3dc8834f15a9636f41fec11ab67724139af"`
[INFO] [stderr]    Compiling serde_tuple v0.2.5 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.81s
[INFO] running `"docker" "inspect" "4dd39d9e1864675be905ac4c0568d3dc8834f15a9636f41fec11ab67724139af"`
[INFO] running `"docker" "rm" "-f" "4dd39d9e1864675be905ac4c0568d3dc8834f15a9636f41fec11ab67724139af"`
[INFO] [stdout] 4dd39d9e1864675be905ac4c0568d3dc8834f15a9636f41fec11ab67724139af
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/serde_tuple/0.2.5:/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" "+beta-2019-08-13" "test" "--frozen" "--no-run"`
[INFO] [stdout] 245e69130f49227db190ac60057aad8264ed20f3f57b0ece02c1080c3dc87d6e
[INFO] running `"docker" "start" "-a" "245e69130f49227db190ac60057aad8264ed20f3f57b0ece02c1080c3dc87d6e"`
[INFO] [stderr]    Compiling serde_tuple v0.2.5 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `std::borrow::Cow`
[INFO] [stderr]  --> examples/simple.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::borrow::Cow;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.12s
[INFO] running `"docker" "inspect" "245e69130f49227db190ac60057aad8264ed20f3f57b0ece02c1080c3dc87d6e"`
[INFO] running `"docker" "rm" "-f" "245e69130f49227db190ac60057aad8264ed20f3f57b0ece02c1080c3dc87d6e"`
[INFO] [stdout] 245e69130f49227db190ac60057aad8264ed20f3f57b0ece02c1080c3dc87d6e
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/serde_tuple/0.2.5:/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" "+beta-2019-08-13" "test" "--frozen"`
[INFO] [stdout] 53c49681df7e65990dec0be9f7142f4f493a8b7d74ef7202bdca4bfe57100851
[INFO] running `"docker" "start" "-a" "53c49681df7e65990dec0be9f7142f4f493a8b7d74ef7202bdca4bfe57100851"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/serde_tuple-d9095d5d40dd17aa
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests serde_tuple
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stderr] 
[INFO] [stderr] thread 'rustc' has overflowed its stack
[INFO] [stderr] fatal runtime error: stack overflow
[INFO] [stderr] error: process didn't exit successfully: `rustdoc --edition=2018 --test /opt/crater/workdir/src/lib.rs --crate-name serde_tuple -L dependency=/opt/crater/target/debug/deps -L dependency=/opt/crater/target/debug/deps --extern proc_macro2=/opt/crater/target/debug/deps/libproc_macro2-83a58f61c7309abf.rlib --extern quote=/opt/crater/target/debug/deps/libquote-5c64d1f6eadb0381.rlib --extern serde=/opt/crater/target/debug/deps/libserde-5125a48878b1da57.rlib --extern serde_derive=/opt/crater/target/debug/deps/libserde_derive-080adf51b2cd98e4.so --extern serde_json=/opt/crater/target/debug/deps/libserde_json-0c53888b338bdcbb.rlib --extern serde_tuple=/opt/crater/target/debug/deps/libserde_tuple-b5da983bbadd07f4.so --extern syn=/opt/crater/target/debug/deps/libsyn-8c07a7a36c75c561.rlib` (signal: 6, SIGABRT: process abort signal)
[INFO] running `"docker" "inspect" "53c49681df7e65990dec0be9f7142f4f493a8b7d74ef7202bdca4bfe57100851"`
[INFO] running `"docker" "rm" "-f" "53c49681df7e65990dec0be9f7142f4f493a8b7d74ef7202bdca4bfe57100851"`
[INFO] [stdout] 53c49681df7e65990dec0be9f7142f4f493a8b7d74ef7202bdca4bfe57100851