[INFO] fetching crate lain 0.5.2...
[INFO] checking lain-0.5.2 against try#72f88fc4e9458f89516a0b8b0868f3718aec5b47 for pr-74989
[INFO] extracting crate lain 0.5.2 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate lain 0.5.2 on toolchain 72f88fc4e9458f89516a0b8b0868f3718aec5b47
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+72f88fc4e9458f89516a0b8b0868f3718aec5b47" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate lain 0.5.2
[INFO] finished tweaking crates.io crate lain 0.5.2
[INFO] tweaked toml for crates.io crate lain 0.5.2 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+72f88fc4e9458f89516a0b8b0868f3718aec5b47" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+72f88fc4e9458f89516a0b8b0868f3718aec5b47" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded field-offset v0.3.2
[INFO] [stderr]   Downloaded lain_derive v0.5.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+72f88fc4e9458f89516a0b8b0868f3718aec5b47" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e979c8bf64e7a75512172d3a08f1bc37facc39d93dce25d5641b59be841f27c5
[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" "e979c8bf64e7a75512172d3a08f1bc37facc39d93dce25d5641b59be841f27c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e979c8bf64e7a75512172d3a08f1bc37facc39d93dce25d5641b59be841f27c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e979c8bf64e7a75512172d3a08f1bc37facc39d93dce25d5641b59be841f27c5", kill_on_drop: false }`
[INFO] [stdout] e979c8bf64e7a75512172d3a08f1bc37facc39d93dce25d5641b59be841f27c5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+72f88fc4e9458f89516a0b8b0868f3718aec5b47" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1f4face9adcb03f5d9259245fb0b12b030a1c5dcd78df9b79d0dfa82acb1d57f
[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" "1f4face9adcb03f5d9259245fb0b12b030a1c5dcd78df9b79d0dfa82acb1d57f", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.77
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling num-bigint v0.2.6
[INFO] [stderr]    Compiling num-iter v0.1.41
[INFO] [stderr]    Compiling num-rational v0.2.4
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling field-offset v0.3.2
[INFO] [stderr]    Compiling mashup v0.1.12
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]     Checking getrandom v0.1.15
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand_pcg v0.2.1
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]    Compiling lain_derive v0.5.2
[INFO] [stderr]     Checking lain v0.5.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]    --> src/lib.rs:101:12
[INFO] [stdout]     |
[INFO] [stdout] 101 | #![feature(specialization)]
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]     = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]    --> src/lib.rs:101:12
[INFO] [stdout]     |
[INFO] [stdout] 101 | #![feature(specialization)]
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]     = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/mutatable.rs:327:13
[INFO] [stdout]     |
[INFO] [stdout] 327 |         let mut constraints = constraints.and_then(|c| {
[INFO] [stdout]     |             ----^^^^^^^^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/mutatable.rs:643:25
[INFO] [stdout]     |
[INFO] [stdout] 643 |                     let mut new_item = T::new_fuzzed(mutator, constraints);
[INFO] [stdout]     |                         ----^^^^^^^^
[INFO] [stdout]     |                         |
[INFO] [stdout]     |                         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/new_fuzzed.rs:777:25
[INFO] [stdout]     |
[INFO] [stdout] 777 |                       let mut per_item_max_size: Option<usize> = constraints.and_then(|c| c.max_size.as_ref().and_then(|size| Some(*size / ...
[INFO] [stdout]     |                           ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           help: remove this `mut`
[INFO] [stdout] ...
[INFO] [stdout] 858 | / impl_new_fuzzed_array!(
[INFO] [stdout] 859 | |     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
[INFO] [stdout] 860 | |     27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
[INFO] [stdout] 861 | |     51, 52, 53, 54, 55, 56, 57, 58, 59, 60
[INFO] [stdout] 862 | | );
[INFO] [stdout]     | |__- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/new_fuzzed.rs:831:25
[INFO] [stdout]     |
[INFO] [stdout] 831 |                       let mut per_item_max_size: Option<usize> = constraints.and_then(|c| c.max_size.as_ref().and_then(|size| Some(*size / ...
[INFO] [stdout]     |                           ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           help: remove this `mut`
[INFO] [stdout] ...
[INFO] [stdout] 858 | / impl_new_fuzzed_array!(
[INFO] [stdout] 859 | |     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
[INFO] [stdout] 860 | |     27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
[INFO] [stdout] 861 | |     51, 52, 53, 54, 55, 56, 57, 58, 59, 60
[INFO] [stdout] 862 | | );
[INFO] [stdout]     | |__- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/mutatable.rs:327:13
[INFO] [stdout]     |
[INFO] [stdout] 327 |         let mut constraints = constraints.and_then(|c| {
[INFO] [stdout]     |             ----^^^^^^^^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/mutatable.rs:643:25
[INFO] [stdout]     |
[INFO] [stdout] 643 |                     let mut new_item = T::new_fuzzed(mutator, constraints);
[INFO] [stdout]     |                         ----^^^^^^^^
[INFO] [stdout]     |                         |
[INFO] [stdout]     |                         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/new_fuzzed.rs:777:25
[INFO] [stdout]     |
[INFO] [stdout] 777 |                       let mut per_item_max_size: Option<usize> = constraints.and_then(|c| c.max_size.as_ref().and_then(|size| Some(*size / ...
[INFO] [stdout]     |                           ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           help: remove this `mut`
[INFO] [stdout] ...
[INFO] [stdout] 858 | / impl_new_fuzzed_array!(
[INFO] [stdout] 859 | |     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
[INFO] [stdout] 860 | |     27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
[INFO] [stdout] 861 | |     51, 52, 53, 54, 55, 56, 57, 58, 59, 60
[INFO] [stdout] 862 | | );
[INFO] [stdout]     | |__- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/new_fuzzed.rs:831:25
[INFO] [stdout]     |
[INFO] [stdout] 831 |                       let mut per_item_max_size: Option<usize> = constraints.and_then(|c| c.max_size.as_ref().and_then(|size| Some(*size / ...
[INFO] [stdout]     |                           ----^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           help: remove this `mut`
[INFO] [stdout] ...
[INFO] [stdout] 858 | / impl_new_fuzzed_array!(
[INFO] [stdout] 859 | |     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
[INFO] [stdout] 860 | |     27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
[INFO] [stdout] 861 | |     51, 52, 53, 54, 55, 56, 57, 58, 59, 60
[INFO] [stdout] 862 | | );
[INFO] [stdout]     | |__- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 27.51s
[INFO] running `Command { std: "docker" "inspect" "1f4face9adcb03f5d9259245fb0b12b030a1c5dcd78df9b79d0dfa82acb1d57f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1f4face9adcb03f5d9259245fb0b12b030a1c5dcd78df9b79d0dfa82acb1d57f", kill_on_drop: false }`
[INFO] [stdout] 1f4face9adcb03f5d9259245fb0b12b030a1c5dcd78df9b79d0dfa82acb1d57f
