Dec 12 09:45:34.340 INFO checking proptest-0.8.7 against master#3a75e80557a103497cffbcab395a2f37061a77ea for pr-56677
Dec 12 09:45:34.340 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56677/worker-2/master#3a75e80557a103497cffbcab395a2f37061a77ea:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-2/pr-56677/master#3a75e80557a103497cffbcab395a2f37061a77ea:/source:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/source" "-e" "USER_ID=1000" "-e" "CMD=cargo +3a75e80557a103497cffbcab395a2f37061a77ea-alt check --frozen --all --all-targets" "-e" "CARGO_TARGET_DIR=/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/cargo-home" "-e" "RUSTUP_HOME=/rustup-home" "-m" "1536M" "--network" "none" "crater"`
Dec 12 09:45:34.736 INFO [stdout] c48c09ca4a2c93fa6d49b812550a08b15b6e7aafcb54e9f142a6a8352b7eb314
Dec 12 09:45:34.744 INFO running `"docker" "start" "-a" "c48c09ca4a2c93fa6d49b812550a08b15b6e7aafcb54e9f142a6a8352b7eb314"`
Dec 12 09:45:35.896 INFO [stderr] usermod: no changes
Dec 12 09:45:36.125 INFO [stderr]     Checking rand v0.5.5
Dec 12 09:45:38.776 INFO [stderr]     Checking proptest v0.8.7 (/source)
Dec 12 09:45:53.607 INFO [stderr] warning: unused `core::result::Result` that must be used
Dec 12 09:45:53.608 INFO [stderr]    --> src/test_runner/failure_persistence/file.rs:308:5
Dec 12 09:45:53.608 INFO [stderr]     |
Dec 12 09:45:53.609 INFO [stderr] 308 |     write!(buf, "{}", format_basic_seed_line(seed));
Dec 12 09:45:53.609 INFO [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 12 09:45:53.609 INFO [stderr]     |
Dec 12 09:45:53.609 INFO [stderr]     = note: #[warn(unused_must_use)] on by default
Dec 12 09:45:53.609 INFO [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
Dec 12 09:45:53.609 INFO [stderr]     = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
Dec 12 09:45:53.609 INFO [stderr] 
Dec 12 09:46:09.344 INFO [stderr] warning: unused `core::result::Result` that must be used
Dec 12 09:46:09.344 INFO [stderr]    --> src/test_runner/failure_persistence/file.rs:308:5
Dec 12 09:46:09.344 INFO [stderr]     |
Dec 12 09:46:09.344 INFO [stderr] 308 |     write!(buf, "{}", format_basic_seed_line(seed));
Dec 12 09:46:09.344 INFO [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 12 09:46:09.344 INFO [stderr]     |
Dec 12 09:46:09.344 INFO [stderr]     = note: #[warn(unused_must_use)] on by default
Dec 12 09:46:09.344 INFO [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
Dec 12 09:46:09.344 INFO [stderr]     = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
Dec 12 09:46:09.344 INFO [stderr] 
Dec 12 09:46:09.817 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 33.89s
Dec 12 09:46:09.829 INFO [stderr] su: No module specific data is present
Dec 12 09:46:10.807 INFO running `"docker" "inspect" "c48c09ca4a2c93fa6d49b812550a08b15b6e7aafcb54e9f142a6a8352b7eb314"`
Dec 12 09:46:11.204 INFO running `"docker" "rm" "-f" "c48c09ca4a2c93fa6d49b812550a08b15b6e7aafcb54e9f142a6a8352b7eb314"`
Dec 12 09:46:11.580 INFO [stdout] c48c09ca4a2c93fa6d49b812550a08b15b6e7aafcb54e9f142a6a8352b7eb314