[INFO] crate rustsync 0.2.3 is already in cache
[INFO] extracting crate rustsync 0.2.3 into work/ex/beta-1.38-1/sources/1.37.0/reg/rustsync/0.2.3
[INFO] extracting crate rustsync 0.2.3 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/rustsync/0.2.3
[INFO] validating manifest of rustsync-0.2.3 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 rustsync-0.2.3 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 rustsync-0.2.3
[INFO] finished frobbing rustsync-0.2.3
[INFO] frobbed toml for rustsync-0.2.3 written to work/ex/beta-1.38-1/sources/1.37.0/reg/rustsync/0.2.3/Cargo.toml
[INFO] started frobbing rustsync-0.2.3
[INFO] finished frobbing rustsync-0.2.3
[INFO] frobbed toml for rustsync-0.2.3 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/rustsync/0.2.3/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] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing rustsync-0.2.3 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-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/rustsync/0.2.3:/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=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] 17bd48236cb59142f3f11d3bdc46c3176501ab2d3c61b5e36266e8135be7d90c
[INFO] running `"docker" "start" "-a" "17bd48236cb59142f3f11d3bdc46c3176501ab2d3c61b5e36266e8135be7d90c"`
[INFO] [stderr]    Compiling blake2-rfc v0.2.18
[INFO] [stderr]    Compiling rustsync v0.2.3 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:243:41
[INFO] [stderr]     |
[INFO] [stderr] 243 |                 if let Async::Ready((r, mut block, len)) = reading.poll()? {
[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] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:430:29
[INFO] [stderr]     |
[INFO] [stderr] 430 |                         let mut hash = adler32::RollingAdler32::from_buffer(&block.as_ref()[..len]);
[INFO] [stderr]     |                             ----^^^^
[INFO] [stderr]     |                             |
[INFO] [stderr]     |                             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.72s
[INFO] running `"docker" "inspect" "17bd48236cb59142f3f11d3bdc46c3176501ab2d3c61b5e36266e8135be7d90c"`
[INFO] running `"docker" "rm" "-f" "17bd48236cb59142f3f11d3bdc46c3176501ab2d3c61b5e36266e8135be7d90c"`
[INFO] [stdout] 17bd48236cb59142f3f11d3bdc46c3176501ab2d3c61b5e36266e8135be7d90c
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/rustsync/0.2.3:/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=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] 3f8de785868afe48102d361e306e23d282d496a0ee0d54b9fa64f6d358b96a12
[INFO] running `"docker" "start" "-a" "3f8de785868afe48102d361e306e23d282d496a0ee0d54b9fa64f6d358b96a12"`
[INFO] [stderr]    Compiling rustsync v0.2.3 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:243:41
[INFO] [stderr]     |
[INFO] [stderr] 243 |                 if let Async::Ready((r, mut block, len)) = reading.poll()? {
[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] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:430:29
[INFO] [stderr]     |
[INFO] [stderr] 430 |                         let mut hash = adler32::RollingAdler32::from_buffer(&block.as_ref()[..len]);
[INFO] [stderr]     |                             ----^^^^
[INFO] [stderr]     |                             |
[INFO] [stderr]     |                             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.92s
[INFO] running `"docker" "inspect" "3f8de785868afe48102d361e306e23d282d496a0ee0d54b9fa64f6d358b96a12"`
[INFO] running `"docker" "rm" "-f" "3f8de785868afe48102d361e306e23d282d496a0ee0d54b9fa64f6d358b96a12"`
[INFO] [stdout] 3f8de785868afe48102d361e306e23d282d496a0ee0d54b9fa64f6d358b96a12
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/rustsync/0.2.3:/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=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] 6f25fe47c6cd74cfc46c831f8f3c4bd6a20ce32467ed4b533277cb3a46e22d31
[INFO] running `"docker" "start" "-a" "6f25fe47c6cd74cfc46c831f8f3c4bd6a20ce32467ed4b533277cb3a46e22d31"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.06s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/rustsync-4409d14cadb4c159
[INFO] [stdout] 
[INFO] [stdout] running 2 tests
[INFO] [stdout] test tests::basic ... ok
[INFO] [stdout] test tests::futures ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests rustsync
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test src/lib.rs -  (line 4) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "6f25fe47c6cd74cfc46c831f8f3c4bd6a20ce32467ed4b533277cb3a46e22d31"`
[INFO] running `"docker" "rm" "-f" "6f25fe47c6cd74cfc46c831f8f3c4bd6a20ce32467ed4b533277cb3a46e22d31"`
[INFO] [stdout] 6f25fe47c6cd74cfc46c831f8f3c4bd6a20ce32467ed4b533277cb3a46e22d31