Dec 18 17:00:39.475 INFO checking discard-1.0.4 against master#96d1334e567237b1507cd277938e7ae2de75ff51 for pr-54252
Dec 18 17:00:39.475 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-54252/worker-0/master#96d1334e567237b1507cd277938e7ae2de75ff51:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-54252/sources/master#96d1334e567237b1507cd277938e7ae2de75ff51/reg/discard/1.0.4:/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=forbid" "-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" "+96d1334e567237b1507cd277938e7ae2de75ff51-alt" "check" "--frozen" "--all" "--all-targets"`
Dec 18 17:00:39.850 INFO [stdout] c2db0e459f42e8fe5e4352e0cd053927809a177fac2fd1cf7a2c8df24dee853a
Dec 18 17:00:39.854 INFO running `"docker" "start" "-a" "c2db0e459f42e8fe5e4352e0cd053927809a177fac2fd1cf7a2c8df24dee853a"`
Dec 18 17:00:41.060 INFO [stderr]     Checking discard v1.0.4 (/opt/crater/workdir)
Dec 18 17:00:41.524 INFO [stderr] warning: unused `DiscardOnDrop` that must be used
Dec 18 17:00:41.524 INFO [stderr]    --> src/lib.rs:261:9
Dec 18 17:00:41.524 INFO [stderr]     |
Dec 18 17:00:41.524 INFO [stderr] 261 |         DiscardOnDrop::new(Foo::new());
Dec 18 17:00:41.524 INFO [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 18 17:00:41.524 INFO [stderr]     |
Dec 18 17:00:41.524 INFO [stderr]     = note: #[warn(unused_must_use)] on by default
Dec 18 17:00:41.524 INFO [stderr]     = note: 
Dec 18 17:00:41.524 INFO [stderr]             The DiscardOnDrop is unused, which causes it to be immediately discarded.
Dec 18 17:00:41.524 INFO [stderr]             You probably don't want that to happen.
Dec 18 17:00:41.524 INFO [stderr]             
Dec 18 17:00:41.524 INFO [stderr]             How to fix this:
Dec 18 17:00:41.524 INFO [stderr]             
Dec 18 17:00:41.525 INFO [stderr]               * Store the DiscardOnDrop in a variable or data structure.
Dec 18 17:00:41.525 INFO [stderr]             
Dec 18 17:00:41.525 INFO [stderr]               * Or use the DiscardOnDrop::leak function which will cause it to not be
Dec 18 17:00:41.525 INFO [stderr]                 discarded (this *will* leak memory!).
Dec 18 17:00:41.525 INFO [stderr]             
Dec 18 17:00:41.525 INFO [stderr]             See the DiscardOnDrop documentation for more details.
Dec 18 17:00:41.525 INFO [stderr] 
Dec 18 17:00:41.525 INFO [stderr] warning: unused `DiscardOnDrop` that must be used
Dec 18 17:00:41.525 INFO [stderr]    --> src/lib.rs:262:9
Dec 18 17:00:41.525 INFO [stderr]     |
Dec 18 17:00:41.525 INFO [stderr] 262 |         DiscardOnDrop::new(Foo::new());
Dec 18 17:00:41.525 INFO [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 18 17:00:41.525 INFO [stderr]     |
Dec 18 17:00:41.525 INFO [stderr]     = note: 
Dec 18 17:00:41.525 INFO [stderr]             The DiscardOnDrop is unused, which causes it to be immediately discarded.
Dec 18 17:00:41.525 INFO [stderr]             You probably don't want that to happen.
Dec 18 17:00:41.525 INFO [stderr]             
Dec 18 17:00:41.525 INFO [stderr]             How to fix this:
Dec 18 17:00:41.525 INFO [stderr]             
Dec 18 17:00:41.525 INFO [stderr]               * Store the DiscardOnDrop in a variable or data structure.
Dec 18 17:00:41.525 INFO [stderr]             
Dec 18 17:00:41.525 INFO [stderr]               * Or use the DiscardOnDrop::leak function which will cause it to not be
Dec 18 17:00:41.525 INFO [stderr]                 discarded (this *will* leak memory!).
Dec 18 17:00:41.525 INFO [stderr]             
Dec 18 17:00:41.525 INFO [stderr]             See the DiscardOnDrop documentation for more details.
Dec 18 17:00:41.525 INFO [stderr] 
Dec 18 17:00:41.556 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.54s
Dec 18 17:00:41.908 INFO running `"docker" "inspect" "c2db0e459f42e8fe5e4352e0cd053927809a177fac2fd1cf7a2c8df24dee853a"`
Dec 18 17:00:42.149 INFO running `"docker" "rm" "-f" "c2db0e459f42e8fe5e4352e0cd053927809a177fac2fd1cf7a2c8df24dee853a"`
Dec 18 17:00:42.468 INFO [stdout] c2db0e459f42e8fe5e4352e0cd053927809a177fac2fd1cf7a2c8df24dee853a