[INFO] fetching crate nature_integrate_test_converter 0.0.2...
[INFO] testing nature_integrate_test_converter-0.0.2 against 1.47.0 for beta-1.48-1
[INFO] extracting crate nature_integrate_test_converter 0.0.2 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate nature_integrate_test_converter 0.0.2 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate nature_integrate_test_converter 0.0.2
[INFO] finished tweaking crates.io crate nature_integrate_test_converter 0.0.2
[INFO] tweaked toml for crates.io crate nature_integrate_test_converter 0.0.2 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6142835d84b07975c634953b723b86bdbd9172e045ff60c216c5b5683905799b
[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" "6142835d84b07975c634953b723b86bdbd9172e045ff60c216c5b5683905799b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6142835d84b07975c634953b723b86bdbd9172e045ff60c216c5b5683905799b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6142835d84b07975c634953b723b86bdbd9172e045ff60c216c5b5683905799b", kill_on_drop: false }`
[INFO] [stdout] 6142835d84b07975c634953b723b86bdbd9172e045ff60c216c5b5683905799b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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=warn" "-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" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2eccec84ec556a41b109f042b8083523070eb15eace79aa887a1fad3f528ca2b
[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" "2eccec84ec556a41b109f042b8083523070eb15eace79aa887a1fad3f528ca2b", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling getrandom v0.2.0
[INFO] [stderr]    Compiling match_cfg v0.1.0
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling percent-encoding v2.1.0
[INFO] [stderr]    Compiling copyless v0.1.5
[INFO] [stderr]    Compiling httparse v1.3.4
[INFO] [stderr]    Compiling encoding_rs v0.8.24
[INFO] [stderr]    Compiling language-tags v0.2.2
[INFO] [stderr]    Compiling mime v0.3.16
[INFO] [stderr]    Compiling sha1 v0.6.0
[INFO] [stderr]    Compiling hashbrown v0.3.1
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling actix-service v0.4.2
[INFO] [stderr]    Compiling rand_jitter v0.1.4
[INFO] [stderr]    Compiling crossbeam-utils v0.6.6
[INFO] [stderr]    Compiling lock_api v0.2.0
[INFO] [stderr]    Compiling lru-cache v0.1.2
[INFO] [stderr]    Compiling uuid v0.7.4
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling idna v0.2.0
[INFO] [stderr]    Compiling socket2 v0.3.15
[INFO] [stderr]    Compiling hostname v0.3.1
[INFO] [stderr]    Compiling time v0.1.44
[INFO] [stderr]    Compiling base64 v0.10.1
[INFO] [stderr]    Compiling parking_lot_core v0.5.0
[INFO] [stderr]    Compiling parking_lot v0.8.0
[INFO] [stderr]    Compiling threadpool v1.8.1
[INFO] [stderr]    Compiling resolv-conf v0.6.3
[INFO] [stderr]    Compiling crossbeam-channel v0.3.9
[INFO] [stderr]    Compiling http v0.1.21
[INFO] [stderr]    Compiling string v0.2.1
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling hashbrown v0.6.3
[INFO] [stderr]    Compiling url v2.1.1
[INFO] [stderr]    Compiling const-random-macro v0.1.11
[INFO] [stderr]    Compiling actix-codec v0.1.2
[INFO] [stderr]    Compiling actix-server-config v0.1.2
[INFO] [stderr]    Compiling actix-utils v0.4.7
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling const-random v0.1.11
[INFO] [stderr]    Compiling ahash v0.2.19
[INFO] [stderr]    Compiling chrono v0.4.19
[INFO] [stderr]    Compiling serde_urlencoded v0.6.1
[INFO] [stderr]    Compiling fern v0.5.9
[INFO] [stderr]    Compiling h2 v0.1.26
[INFO] [stderr]    Compiling derive_more v0.15.0
[INFO] [stderr]    Compiling enum-as-inner v0.2.1
[INFO] [stderr]    Compiling derive_more v0.14.1
[INFO] [stderr]    Compiling actix_derive v0.4.0
[INFO] [stderr]    Compiling trust-dns-proto v0.7.4
[INFO] [stderr]    Compiling trust-dns-resolver v0.11.1
[INFO] [stderr]    Compiling actix-threadpool v0.1.2
[INFO] [stderr]    Compiling actix-rt v0.2.6
[INFO] [stderr]    Compiling actix-connect v0.2.5
[INFO] [stderr]    Compiling actix-http v0.2.11
[INFO] [stderr]    Compiling actix v0.8.3
[INFO] [stderr]    Compiling nature_common v0.0.2
[INFO] [stderr]    Compiling nature_integrate_test_converter v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]  --> src/lib.rs:8:55
[INFO] [stdout]   |
[INFO] [stdout] 8 | pub extern fn rtn_none(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]   |                                                       ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(improper_ctypes_definitions)]` on by default
[INFO] [stdout]   = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]   = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:15:64
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub extern fn rtn_logical_error(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                                ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:22:54
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub extern fn rtn_one(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:31:54
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub extern fn rtn_tow(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:42:68
[INFO] [stdout]    |
[INFO] [stdout] 42 | pub extern fn rtn_environment_error(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                                    ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 57s
[INFO] running `Command { std: "docker" "inspect" "2eccec84ec556a41b109f042b8083523070eb15eace79aa887a1fad3f528ca2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2eccec84ec556a41b109f042b8083523070eb15eace79aa887a1fad3f528ca2b", kill_on_drop: false }`
[INFO] [stdout] 2eccec84ec556a41b109f042b8083523070eb15eace79aa887a1fad3f528ca2b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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=warn" "-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" "+1.47.0" "test" "--frozen" "--no-run" "--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] 0fb14cfb9a79b99382bfe5a177723756f8da851b8948b4033a96c403db7a0c46
[INFO] running `Command { std: "docker" "start" "-a" "0fb14cfb9a79b99382bfe5a177723756f8da851b8948b4033a96c403db7a0c46", kill_on_drop: false }`
[INFO] [stderr]    Compiling nature_integrate_test_converter v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]  --> src/lib.rs:8:55
[INFO] [stdout]   |
[INFO] [stdout] 8 | pub extern fn rtn_none(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]   |                                                       ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(improper_ctypes_definitions)]` on by default
[INFO] [stdout]   = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]   = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:15:64
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub extern fn rtn_logical_error(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                                ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:22:54
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub extern fn rtn_one(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:31:54
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub extern fn rtn_tow(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                      ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stdout]   --> src/lib.rs:42:68
[INFO] [stdout]    |
[INFO] [stdout] 42 | pub extern fn rtn_environment_error(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stdout]    |                                                                    ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stdout]    = note: enum has no representation hint
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 5.22s
[INFO] running `Command { std: "docker" "inspect" "0fb14cfb9a79b99382bfe5a177723756f8da851b8948b4033a96c403db7a0c46", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0fb14cfb9a79b99382bfe5a177723756f8da851b8948b4033a96c403db7a0c46", kill_on_drop: false }`
[INFO] [stdout] 0fb14cfb9a79b99382bfe5a177723756f8da851b8948b4033a96c403db7a0c46
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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=warn" "-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" "+1.47.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] e207c901786c4cdcbb72ac2316d5b63b5d833267dacbbc566a5f0af34f784ed3
[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" "e207c901786c4cdcbb72ac2316d5b63b5d833267dacbbc566a5f0af34f784ed3", kill_on_drop: false }`
[INFO] [stderr] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stderr]  --> src/lib.rs:8:55
[INFO] [stderr]   |
[INFO] [stderr] 8 | pub extern fn rtn_none(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stderr]   |                                                       ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(improper_ctypes_definitions)]` on by default
[INFO] [stderr]   = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stderr]   = note: enum has no representation hint
[INFO] [stderr] 
[INFO] [stderr] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stderr]   --> src/lib.rs:15:64
[INFO] [stderr]    |
[INFO] [stderr] 15 | pub extern fn rtn_logical_error(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stderr]    |                                                                ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stderr]    = note: enum has no representation hint
[INFO] [stderr] 
[INFO] [stderr] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stderr]   --> src/lib.rs:22:54
[INFO] [stderr]    |
[INFO] [stderr] 22 | pub extern fn rtn_one(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stderr]    |                                                      ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stderr]    = note: enum has no representation hint
[INFO] [stderr] 
[INFO] [stderr] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stderr]   --> src/lib.rs:31:54
[INFO] [stderr]    |
[INFO] [stderr] 31 | pub extern fn rtn_tow(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stderr]    |                                                      ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stderr]    = note: enum has no representation hint
[INFO] [stderr] 
[INFO] [stderr] warning: `extern` fn uses type `nature_common::ConverterReturned`, which is not FFI-safe
[INFO] [stderr]   --> src/lib.rs:42:68
[INFO] [stderr]    |
[INFO] [stderr] 42 | pub extern fn rtn_environment_error(_para: &ConverterParameter) -> ConverterReturned {
[INFO] [stderr]    |                                                                    ^^^^^^^^^^^^^^^^^ not FFI-safe
[INFO] [stderr]    |
[INFO] [stderr]    = help: consider adding a `#[repr(C)]`, `#[repr(transparent)]`, or integer `#[repr(...)]` attribute to this enum
[INFO] [stderr]    = note: enum has no representation hint
[INFO] [stderr] 
[INFO] [stderr] warning: 5 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.46s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/nature_integrate_test_converter-1dd9d24ba1cb2602
[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 `Command { std: "docker" "inspect" "e207c901786c4cdcbb72ac2316d5b63b5d833267dacbbc566a5f0af34f784ed3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e207c901786c4cdcbb72ac2316d5b63b5d833267dacbbc566a5f0af34f784ed3", kill_on_drop: false }`
[INFO] [stdout] e207c901786c4cdcbb72ac2316d5b63b5d833267dacbbc566a5f0af34f784ed3
