[INFO] fetching crate mtpng 0.3.4...
[INFO] checking mtpng-0.3.4 against try#f6e2f78768c57172b99c3e85892f867894dc7e30 for pr-75502
[INFO] extracting crate mtpng 0.3.4 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate mtpng 0.3.4 on toolchain f6e2f78768c57172b99c3e85892f867894dc7e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mtpng 0.3.4
[INFO] finished tweaking crates.io crate mtpng 0.3.4
[INFO] tweaked toml for crates.io crate mtpng 0.3.4 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate crates.io crate mtpng 0.3.4 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5ef9c9f9111b6823c82c65329fdacda31d3638df21d4410cfcd8b7df32889f20
[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" "5ef9c9f9111b6823c82c65329fdacda31d3638df21d4410cfcd8b7df32889f20", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5ef9c9f9111b6823c82c65329fdacda31d3638df21d4410cfcd8b7df32889f20", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5ef9c9f9111b6823c82c65329fdacda31d3638df21d4410cfcd8b7df32889f20", kill_on_drop: false }`
[INFO] [stdout] 5ef9c9f9111b6823c82c65329fdacda31d3638df21d4410cfcd8b7df32889f20
[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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4b6b414e655d77696cba03c22b9a6cb817c680553d484fbcda4a66d96c1aa69d
[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" "4b6b414e655d77696cba03c22b9a6cb817c680553d484fbcda4a66d96c1aa69d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.50
[INFO] [stderr]    Compiling arrayvec v0.4.10
[INFO] [stderr]     Checking cfg-if v0.1.7
[INFO] [stderr]     Checking scopeguard v1.0.0
[INFO] [stderr]    Compiling cc v1.0.31
[INFO] [stderr]    Compiling pkg-config v0.3.14
[INFO] [stderr]     Checking either v1.5.1
[INFO] [stderr]    Compiling memoffset v0.5.1
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking crossbeam-queue v0.1.2
[INFO] [stderr]     Checking crossbeam-epoch v0.7.2
[INFO] [stderr]     Checking crossbeam-deque v0.6.3
[INFO] [stderr]    Compiling libz-sys v1.0.25
[INFO] [stderr]     Checking num_cpus v1.10.0
[INFO] [stderr]     Checking rayon-core v1.5.0
[INFO] [stderr]     Checking rayon v1.1.0
[INFO] [stderr]     Checking mtpng v0.3.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the type `libz_sys::z_stream` does not permit zero-initialization
[INFO] [stdout]    --> src/deflate.rs:150:17
[INFO] [stdout]     |
[INFO] [stdout] 150 |                 mem::MaybeUninit::zeroed().assume_init()
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 this code causes undefined behavior when executed
[INFO] [stdout]     |                 help: use `MaybeUninit<T>` instead, and only call `assume_init` after initialization is done
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(invalid_value)]` on by default
[INFO] [stdout] note: function pointers must be non-null (in this struct field)
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/libz-sys-1.0.25/src/lib.rs:57:5
[INFO] [stdout]     |
[INFO] [stdout] 57  |     pub zalloc: alloc_func,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the type `libz_sys::z_stream` does not permit zero-initialization
[INFO] [stdout]    --> src/deflate.rs:150:17
[INFO] [stdout]     |
[INFO] [stdout] 150 |                 mem::MaybeUninit::zeroed().assume_init()
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 this code causes undefined behavior when executed
[INFO] [stdout]     |                 help: use `MaybeUninit<T>` instead, and only call `assume_init` after initialization is done
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(invalid_value)]` on by default
[INFO] [stdout] note: function pointers must be non-null (in this struct field)
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/libz-sys-1.0.25/src/lib.rs:57:5
[INFO] [stdout]     |
[INFO] [stdout] 57  |     pub zalloc: alloc_func,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 13.73s
[INFO] running `Command { std: "docker" "inspect" "4b6b414e655d77696cba03c22b9a6cb817c680553d484fbcda4a66d96c1aa69d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b6b414e655d77696cba03c22b9a6cb817c680553d484fbcda4a66d96c1aa69d", kill_on_drop: false }`
[INFO] [stdout] 4b6b414e655d77696cba03c22b9a6cb817c680553d484fbcda4a66d96c1aa69d