[INFO] updating cached repository llwwns/pairing_heap
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/llwwns/pairing_heap
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/llwwns/pairing_heap" "work/ex/beta-1.38-1/sources/1.37.0/gh/llwwns/pairing_heap"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/llwwns/pairing_heap'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/llwwns/pairing_heap" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/llwwns/pairing_heap"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/llwwns/pairing_heap'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] b8f1c8ff87c95c26a0d04a2ed75c5b818fb34881
[INFO] sha for GitHub repo llwwns/pairing_heap: b8f1c8ff87c95c26a0d04a2ed75c5b818fb34881
[INFO] validating manifest of llwwns/pairing_heap 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 llwwns/pairing_heap 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 llwwns/pairing_heap
[INFO] finished frobbing llwwns/pairing_heap
[INFO] frobbed toml for llwwns/pairing_heap written to work/ex/beta-1.38-1/sources/1.37.0/gh/llwwns/pairing_heap/Cargo.toml
[INFO] started frobbing llwwns/pairing_heap
[INFO] finished frobbing llwwns/pairing_heap
[INFO] frobbed toml for llwwns/pairing_heap written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/llwwns/pairing_heap/Cargo.toml
[INFO] crate llwwns/pairing_heap already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing llwwns/pairing_heap against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-7/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/llwwns/pairing_heap:/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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] ec157757a07a09ac2286ad30c2f4a787203f8540d6f73fda5ba96d672219fbfa
[INFO] running `"docker" "start" "-a" "ec157757a07a09ac2286ad30c2f4a787203f8540d6f73fda5ba96d672219fbfa"`
[INFO] [stderr]    Compiling pairing_heap v0.1.0 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.34s
[INFO] running `"docker" "inspect" "ec157757a07a09ac2286ad30c2f4a787203f8540d6f73fda5ba96d672219fbfa"`
[INFO] running `"docker" "rm" "-f" "ec157757a07a09ac2286ad30c2f4a787203f8540d6f73fda5ba96d672219fbfa"`
[INFO] [stdout] ec157757a07a09ac2286ad30c2f4a787203f8540d6f73fda5ba96d672219fbfa
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-7/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/llwwns/pairing_heap:/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" "+1.37.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] c2c87d38d5cb501bcaf28e27d26a4e8547697ea5e9046b3f2e22aae294cf8955
[INFO] running `"docker" "start" "-a" "c2c87d38d5cb501bcaf28e27d26a4e8547697ea5e9046b3f2e22aae294cf8955"`
[INFO] [stderr]    Compiling pairing_heap v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/forward_list.rs:291:7
[INFO] [stderr]     |
[INFO] [stderr] 291 |   let mut x: Vec<_> = a.into_iter().collect();
[INFO] [stderr]     |       ----^
[INFO] [stderr]     |       |
[INFO] [stderr]     |       help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.68s
[INFO] running `"docker" "inspect" "c2c87d38d5cb501bcaf28e27d26a4e8547697ea5e9046b3f2e22aae294cf8955"`
[INFO] running `"docker" "rm" "-f" "c2c87d38d5cb501bcaf28e27d26a4e8547697ea5e9046b3f2e22aae294cf8955"`
[INFO] [stdout] c2c87d38d5cb501bcaf28e27d26a4e8547697ea5e9046b3f2e22aae294cf8955
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-7/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/llwwns/pairing_heap:/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" "+1.37.0" "test" "--frozen"`
[INFO] [stdout] 70d73eae9292b6df8f55cddb3fb4910ef3f3cf2ab7a00c1497c8b17ebcd4d889
[INFO] running `"docker" "start" "-a" "70d73eae9292b6df8f55cddb3fb4910ef3f3cf2ab7a00c1497c8b17ebcd4d889"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/pairing_heap-535d767db2178ae4
[INFO] [stdout] 
[INFO] [stdout] running 2 tests
[INFO] [stdout] test test ... ok
[INFO] [stdout] test forward_list::test ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/crater/target/debug/deps/main-158e8aa6060c69e2
[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 pairing_heap
[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] running `"docker" "inspect" "70d73eae9292b6df8f55cddb3fb4910ef3f3cf2ab7a00c1497c8b17ebcd4d889"`
[INFO] running `"docker" "rm" "-f" "70d73eae9292b6df8f55cddb3fb4910ef3f3cf2ab7a00c1497c8b17ebcd4d889"`
[INFO] [stdout] 70d73eae9292b6df8f55cddb3fb4910ef3f3cf2ab7a00c1497c8b17ebcd4d889