[INFO] updating cached repository amk91/config_exchanger
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/amk91/config_exchanger
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/amk91/config_exchanger" "work/ex/beta-1.38-1/sources/1.37.0/gh/amk91/config_exchanger"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/amk91/config_exchanger'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/amk91/config_exchanger" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/amk91/config_exchanger"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/amk91/config_exchanger'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 4f6d4b4dba2625887202d3e8b3697f65e21b1fd4
[INFO] sha for GitHub repo amk91/config_exchanger: 4f6d4b4dba2625887202d3e8b3697f65e21b1fd4
[INFO] validating manifest of amk91/config_exchanger 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 amk91/config_exchanger 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 amk91/config_exchanger
[INFO] finished frobbing amk91/config_exchanger
[INFO] frobbed toml for amk91/config_exchanger written to work/ex/beta-1.38-1/sources/1.37.0/gh/amk91/config_exchanger/Cargo.toml
[INFO] started frobbing amk91/config_exchanger
[INFO] finished frobbing amk91/config_exchanger
[INFO] frobbed toml for amk91/config_exchanger written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/amk91/config_exchanger/Cargo.toml
[INFO] crate amk91/config_exchanger 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 amk91/config_exchanger 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-2/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/amk91/config_exchanger:/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] 0c8e0c391bda71b72f47a95c5487944c31e1409419e7d069bdfd1fbd6348093c
[INFO] running `"docker" "start" "-a" "0c8e0c391bda71b72f47a95c5487944c31e1409419e7d069bdfd1fbd6348093c"`
[INFO] [stderr]    Compiling xmlparser v0.6.0
[INFO] [stderr]    Compiling config_exchanger v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/main.rs:244:21
[INFO] [stderr]     |
[INFO] [stderr] 244 |                 let mut buffer = String::from(whitespaces.to_str());
[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 2.96s
[INFO] running `"docker" "inspect" "0c8e0c391bda71b72f47a95c5487944c31e1409419e7d069bdfd1fbd6348093c"`
[INFO] running `"docker" "rm" "-f" "0c8e0c391bda71b72f47a95c5487944c31e1409419e7d069bdfd1fbd6348093c"`
[INFO] [stdout] 0c8e0c391bda71b72f47a95c5487944c31e1409419e7d069bdfd1fbd6348093c
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-2/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/amk91/config_exchanger:/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] 5f3a693c2c194a246aa9fd91c5aad77fc435d9d05cb60a22cbb91ac68fd47a25
[INFO] running `"docker" "start" "-a" "5f3a693c2c194a246aa9fd91c5aad77fc435d9d05cb60a22cbb91ac68fd47a25"`
[INFO] [stderr]    Compiling config_exchanger v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/main.rs:244:21
[INFO] [stderr]     |
[INFO] [stderr] 244 |                 let mut buffer = String::from(whitespaces.to_str());
[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 0.79s
[INFO] running `"docker" "inspect" "5f3a693c2c194a246aa9fd91c5aad77fc435d9d05cb60a22cbb91ac68fd47a25"`
[INFO] running `"docker" "rm" "-f" "5f3a693c2c194a246aa9fd91c5aad77fc435d9d05cb60a22cbb91ac68fd47a25"`
[INFO] [stdout] 5f3a693c2c194a246aa9fd91c5aad77fc435d9d05cb60a22cbb91ac68fd47a25
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-2/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/amk91/config_exchanger:/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] db63ba78f83510e17f4d225e4aebb8202923e40d4f3270f13646743f6de1d6a6
[INFO] running `"docker" "start" "-a" "db63ba78f83510e17f4d225e4aebb8202923e40d4f3270f13646743f6de1d6a6"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/config_exchanger-25836494feacaef5
[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" "db63ba78f83510e17f4d225e4aebb8202923e40d4f3270f13646743f6de1d6a6"`
[INFO] running `"docker" "rm" "-f" "db63ba78f83510e17f4d225e4aebb8202923e40d4f3270f13646743f6de1d6a6"`
[INFO] [stdout] db63ba78f83510e17f4d225e4aebb8202923e40d4f3270f13646743f6de1d6a6