[INFO] fetching crate um32 1.0.2...
[INFO] checking um32-1.0.2 against master#36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923 for pr-81863
[INFO] extracting crate um32 1.0.2 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate um32 1.0.2 on toolchain 36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate um32 1.0.2
[INFO] finished tweaking crates.io crate um32 1.0.2
[INFO] tweaked toml for crates.io crate um32 1.0.2 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:ce6408862c0f4858e6cd2b85b2cf085ff7d0d6323904d0a94b71664a228554ab" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cb4becb67a47e74a8c69c0017e75e97355e45cf981b897ac1f110497f206eb7d
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "cb4becb67a47e74a8c69c0017e75e97355e45cf981b897ac1f110497f206eb7d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cb4becb67a47e74a8c69c0017e75e97355e45cf981b897ac1f110497f206eb7d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cb4becb67a47e74a8c69c0017e75e97355e45cf981b897ac1f110497f206eb7d", kill_on_drop: false }`
[INFO] [stdout] cb4becb67a47e74a8c69c0017e75e97355e45cf981b897ac1f110497f206eb7d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:ce6408862c0f4858e6cd2b85b2cf085ff7d0d6323904d0a94b71664a228554ab" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 621e387af84761aba71323d38024a5b14ff6d9f506d0a6fd4975af3605d33ed0
[INFO] running `Command { std: "docker" "start" "-a" "621e387af84761aba71323d38024a5b14ff6d9f506d0a6fd4975af3605d33ed0", kill_on_drop: false }`
[INFO] [stderr]     Checking byteorder v1.0.0
[INFO] [stderr]     Checking um32 v1.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:175:13
[INFO] [stdout]     |
[INFO] [stdout] 175 | /             mem::replace(
[INFO] [stdout] 176 | |                 self.heap.get_mut(address)
[INFO] [stdout] 177 | |                     .expect("memory was not previously allocated"),
[INFO] [stdout] 178 | |                 zeros
[INFO] [stdout] 179 | |             );
[INFO] [stdout]     | |______________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:188:9
[INFO] [stdout]     |
[INFO] [stdout] 188 | /         mem::replace(
[INFO] [stdout] 189 | |             self.heap.get_mut(address)
[INFO] [stdout] 190 | |                 .expect("memory was not previously allocated"),
[INFO] [stdout] 191 | |             Vec::new()
[INFO] [stdout] 192 | |         );
[INFO] [stdout]     | |__________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:214:9
[INFO] [stdout]     |
[INFO] [stdout] 214 | /         mem::replace(
[INFO] [stdout] 215 | |             memory.get_mut(idx)
[INFO] [stdout] 216 | |                 .expect("no value present at given idx"),
[INFO] [stdout] 217 | |             value
[INFO] [stdout] 218 | |         );
[INFO] [stdout]     | |__________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:227:9
[INFO] [stdout]     |
[INFO] [stdout] 227 | /         mem::replace(
[INFO] [stdout] 228 | |             self.heap.get_mut(PROGRAM_ADDRESS)
[INFO] [stdout] 229 | |                 .expect("found no existing program"),
[INFO] [stdout] 230 | |             program
[INFO] [stdout] 231 | |         );
[INFO] [stdout]     | |__________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:175:13
[INFO] [stdout]     |
[INFO] [stdout] 175 | /             mem::replace(
[INFO] [stdout] 176 | |                 self.heap.get_mut(address)
[INFO] [stdout] 177 | |                     .expect("memory was not previously allocated"),
[INFO] [stdout] 178 | |                 zeros
[INFO] [stdout] 179 | |             );
[INFO] [stdout]     | |______________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:188:9
[INFO] [stdout]     |
[INFO] [stdout] 188 | /         mem::replace(
[INFO] [stdout] 189 | |             self.heap.get_mut(address)
[INFO] [stdout] 190 | |                 .expect("memory was not previously allocated"),
[INFO] [stdout] 191 | |             Vec::new()
[INFO] [stdout] 192 | |         );
[INFO] [stdout]     | |__________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:214:9
[INFO] [stdout]     |
[INFO] [stdout] 214 | /         mem::replace(
[INFO] [stdout] 215 | |             memory.get_mut(idx)
[INFO] [stdout] 216 | |                 .expect("no value present at given idx"),
[INFO] [stdout] 217 | |             value
[INFO] [stdout] 218 | |         );
[INFO] [stdout]     | |__________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/main.rs:227:9
[INFO] [stdout]     |
[INFO] [stdout] 227 | /         mem::replace(
[INFO] [stdout] 228 | |             self.heap.get_mut(PROGRAM_ADDRESS)
[INFO] [stdout] 229 | |                 .expect("found no existing program"),
[INFO] [stdout] 230 | |             program
[INFO] [stdout] 231 | |         );
[INFO] [stdout]     | |__________^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.83s
[INFO] running `Command { std: "docker" "inspect" "621e387af84761aba71323d38024a5b14ff6d9f506d0a6fd4975af3605d33ed0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "621e387af84761aba71323d38024a5b14ff6d9f506d0a6fd4975af3605d33ed0", kill_on_drop: false }`
[INFO] [stdout] 621e387af84761aba71323d38024a5b14ff6d9f506d0a6fd4975af3605d33ed0