[INFO] cloning repository https://github.com/0xCCF4/nix-rs-bindings
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/0xCCF4/nix-rs-bindings" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F0xCCF4%2Fnix-rs-bindings", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F0xCCF4%2Fnix-rs-bindings'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] eb171f1b89306bd37f2fcebd60c651d97bf45e7d
[INFO] checking 0xCCF4/nix-rs-bindings against master#d5419f1e97b90741d51841f800d3c697c662567d for pr-147565
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F0xCCF4%2Fnix-rs-bindings" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/0xCCF4/nix-rs-bindings
[INFO] finished tweaking git repo https://github.com/0xCCF4/nix-rs-bindings
[INFO] tweaked toml for git repo https://github.com/0xCCF4/nix-rs-bindings written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/0xCCF4/nix-rs-bindings on toolchain d5419f1e97b90741d51841f800d3c697c662567d
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d5419f1e97b90741d51841f800d3c697c662567d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/0xCCF4/nix-rs-bindings already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d5419f1e97b90741d51841f800d3c697c662567d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded prettyplease v0.2.36
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d5419f1e97b90741d51841f800d3c697c662567d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e8fe5330fae3dd2aba80dec33fd777c6354572b84fb8bb66a49129d0937c55e7
[INFO] running `Command { std: "docker" "start" "-a" "e8fe5330fae3dd2aba80dec33fd777c6354572b84fb8bb66a49129d0937c55e7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e8fe5330fae3dd2aba80dec33fd777c6354572b84fb8bb66a49129d0937c55e7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e8fe5330fae3dd2aba80dec33fd777c6354572b84fb8bb66a49129d0937c55e7", kill_on_drop: false }`
[INFO] [stdout] e8fe5330fae3dd2aba80dec33fd777c6354572b84fb8bb66a49129d0937c55e7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d5419f1e97b90741d51841f800d3c697c662567d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1efe1a05b18cbd47e9298e445b7d57a4df9b73c10c64b8f99682cc48e1e09338
[INFO] running `Command { std: "docker" "start" "-a" "1efe1a05b18cbd47e9298e445b7d57a4df9b73c10c64b8f99682cc48e1e09338", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.95
[INFO] [stderr]    Compiling glob v0.3.2
[INFO] [stderr]    Compiling prettyplease v0.2.36
[INFO] [stderr]    Compiling bindgen v0.72.0
[INFO] [stderr]    Compiling libc v0.2.174
[INFO] [stderr]    Compiling minimal-lexical v0.2.1
[INFO] [stderr]    Compiling cfg-if v1.0.1
[INFO] [stderr]    Compiling regex-syntax v0.8.5
[INFO] [stderr]    Compiling memchr v2.7.5
[INFO] [stderr]    Compiling either v1.15.0
[INFO] [stderr]    Compiling bitflags v2.9.1
[INFO] [stderr]    Compiling rustc-hash v2.1.1
[INFO] [stderr]    Compiling pkg-config v0.3.32
[INFO] [stderr]     Checking unicode-ident v1.0.18
[INFO] [stderr]    Compiling libloading v0.8.8
[INFO] [stderr]    Compiling itertools v0.13.0
[INFO] [stderr]    Compiling clang-sys v1.8.1
[INFO] [stderr]    Compiling quote v1.0.40
[INFO] [stderr]    Compiling syn v2.0.104
[INFO] [stderr]     Checking nom v7.1.3
[INFO] [stderr]     Checking regex-automata v0.4.9
[INFO] [stderr]     Checking regex v1.11.1
[INFO] [stderr]     Checking cexpr v0.6.0
[INFO] [stderr]     Checking nix-sys-common-build v0.1.0 (/opt/rustwide/workdir/common-build)
[INFO] [stderr]    Compiling nix-exprc-sys v0.1.0 (/opt/rustwide/workdir/nix-exprc-sys)
[INFO] [stderr]    Compiling nix-utilc-sys v0.1.0 (/opt/rustwide/workdir/nix-utilc-sys)
[INFO] [stderr]    Compiling nix-mainc-sys v0.1.0 (/opt/rustwide/workdir/nix-mainc-sys)
[INFO] [stderr]    Compiling nix-storec-sys v0.1.0 (/opt/rustwide/workdir/nix-storec-sys)
[INFO] [stderr]    Compiling nix-flakec-sys v0.1.0 (/opt/rustwide/workdir/nix-flakec-sys)
[INFO] [stderr] warning: nix-utilc-sys@0.1.0: Neither feature 'shared' nor feature 'static' specified -> defaulting to 'shared'.
[INFO] [stderr] error: failed to run custom build command for `nix-utilc-sys v0.1.0 (/opt/rustwide/workdir/nix-utilc-sys)`
[INFO] [stderr] note: To improve backtraces for build dependencies, set the CARGO_PROFILE_DEV_BUILD_OVERRIDE_DEBUG=true environment variable to enable debug information generation.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/target/debug/build/nix-utilc-sys-9127a12f20a1ee4b/build-script-build` (exit status: 101)
[INFO] [stderr]   --- stdout
[INFO] [stderr]   cargo:warning=Neither feature 'shared' nor feature 'static' specified -> defaulting to 'shared'.
[INFO] [stderr]   cargo:rerun-if-env-changed=NIX_UTIL_C_NO_PKG_CONFIG
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_PATH_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_PATH_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG_PATH
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_PATH
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_LIBDIR_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_LIBDIR_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG_LIBDIR
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_LIBDIR
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_SYSROOT_DIR_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_SYSROOT_DIR_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG_SYSROOT_DIR
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_SYSROOT_DIR
[INFO] [stderr] 
[INFO] [stderr]   --- stderr
[INFO] [stderr] 
[INFO] [stderr]   thread 'main' (764) panicked at /opt/rustwide/workdir/common-build/src/lib.rs:35:10:
[INFO] [stderr]   called `Result::unwrap()` on an `Err` value: 
[INFO] [stderr]   pkg-config exited with status code 1
[INFO] [stderr]   > PKG_CONFIG_ALLOW_SYSTEM_LIBS=1 PKG_CONFIG_ALLOW_SYSTEM_CFLAGS=1 pkg-config --libs --cflags nix-util-c
[INFO] [stderr] 
[INFO] [stderr]   The system library `nix-util-c` required by crate `nix-utilc-sys` was not found.
[INFO] [stderr]   The file `nix-util-c.pc` needs to be installed and the PKG_CONFIG_PATH environment variable must contain its parent directory.
[INFO] [stderr]   The PKG_CONFIG_PATH environment variable is not set.
[INFO] [stderr] 
[INFO] [stderr]   HINT: if you have installed the library, try setting PKG_CONFIG_PATH to the directory containing `nix-util-c.pc`.
[INFO] [stderr] 
[INFO] [stderr]   stack backtrace:
[INFO] [stderr]      0:     0x63d6210f6ea2 - std::backtrace_rs::backtrace::libunwind::trace::h11a8b35bc44a0431
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
[INFO] [stderr]      1:     0x63d6210f6ea2 - std::backtrace_rs::backtrace::trace_unsynchronized::h4bb43ab1f2500e57
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
[INFO] [stderr]      2:     0x63d6210f6ea2 - std::sys::backtrace::_print_fmt::h4f91d56a36bf229c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:66:9
[INFO] [stderr]      3:     0x63d6210f6ea2 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h679c418ba9518ec2
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:39:26
[INFO] [stderr]      4:     0x63d62110800f - core::fmt::rt::Argument::fmt::hbeaee41c05518475
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/fmt/rt.rs:173:76
[INFO] [stderr]      5:     0x63d62110800f - core::fmt::write::h51c66197b4d957a8
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/fmt/mod.rs:1469:25
[INFO] [stderr]      6:     0x63d6210c7dd3 - std::io::default_write_fmt::h94cc754f3fb194d4
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/io/mod.rs:639:11
[INFO] [stderr]      7:     0x63d6210c7dd3 - std::io::Write::write_fmt::hd7f9b346821f104c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/io/mod.rs:1954:13
[INFO] [stderr]      8:     0x63d6210d2b22 - std::sys::backtrace::BacktraceLock::print::hc4c7ea61c5866868
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:42:9
[INFO] [stderr]      9:     0x63d6210d5caf - std::panicking::default_hook::{{closure}}::hb732ad1ff6e3a117
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:301:27
[INFO] [stderr]     10:     0x63d6210d5b09 - std::panicking::default_hook::h6de8725131d88596
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:328:9
[INFO] [stderr]     11:     0x63d6210d6335 - std::panicking::panic_with_hook::h7a4b874e601515d2
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:834:13
[INFO] [stderr]     12:     0x63d6210d611a - std::panicking::panic_handler::{{closure}}::hdf12a7672c151d02
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:707:13
[INFO] [stderr]     13:     0x63d6210d2c69 - std::sys::backtrace::__rust_end_short_backtrace::hec84a34dd67d028d
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:174:18
[INFO] [stderr]     14:     0x63d6210bbc3d - __rustc[7bfeb0a5f9a695b4]::rust_begin_unwind
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:698:5
[INFO] [stderr]     15:     0x63d621111e40 - core::panicking::panic_fmt::h1043a43e4c4e7b8a
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/panicking.rs:80:14
[INFO] [stderr]     16:     0x63d6211110a6 - core::result::unwrap_failed::hea0b4eefefc9a5d3
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/result.rs:1862:5
[INFO] [stderr]     17:     0x63d620b45a8d - nix_sys_common_build::configure_library::h6ebf5f43cb068715
[INFO] [stderr]     18:     0x63d620b456e1 - build_script_build::main::hcd4a87bc5e53764e
[INFO] [stderr]     19:     0x63d620b473f3 - core::ops::function::FnOnce::call_once::h8cd4fd697322bbbc
[INFO] [stderr]     20:     0x63d620b47206 - std::sys::backtrace::__rust_begin_short_backtrace::h8e6fce64cbc89591
[INFO] [stderr]     21:     0x63d620b471e9 - std::rt::lang_start::{{closure}}::h5b6ef0518bbe4764
[INFO] [stderr]     22:     0x63d6210c9670 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::he4713d5f5b5fad00
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/ops/function.rs:287:21
[INFO] [stderr]     23:     0x63d6210c9670 - std::panicking::catch_unwind::do_call::hc3ddf565c1f4dde0
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:590:40
[INFO] [stderr]     24:     0x63d6210c9670 - std::panicking::catch_unwind::hb9d05085c95f548e
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:553:19
[INFO] [stderr]     25:     0x63d6210c9670 - std::panic::catch_unwind::h0f5c787d106c8c09
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panic.rs:359:14
[INFO] [stderr]     26:     0x63d6210c9670 - std::rt::lang_start_internal::{{closure}}::h433b499d119da066
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/rt.rs:175:24
[INFO] [stderr]     27:     0x63d6210c9670 - std::panicking::catch_unwind::do_call::hbcdd02e26d5b172c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:590:40
[INFO] [stderr]     28:     0x63d6210c9670 - std::panicking::catch_unwind::h537a562662b7132c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:553:19
[INFO] [stderr]     29:     0x63d6210c9670 - std::panic::catch_unwind::h9c7c44034c3fe654
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panic.rs:359:14
[INFO] [stderr]     30:     0x63d6210c9670 - std::rt::lang_start_internal::h0851b37a761fa7da
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/rt.rs:171:5
[INFO] [stderr]     31:     0x63d620b471d1 - std::rt::lang_start::h17296f7ed0a2d35b
[INFO] [stderr]     32:     0x63d620b49f05 - main
[INFO] [stderr]     33:     0x76ce678b31ca - <unknown>
[INFO] [stderr]     34:     0x76ce678b328b - __libc_start_main
[INFO] [stderr]     35:     0x63d620b453e5 - _start
[INFO] [stderr]     36:                0x0 - <unknown>
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: failed to run custom build command for `nix-exprc-sys v0.1.0 (/opt/rustwide/workdir/nix-exprc-sys)`
[INFO] [stderr] note: To improve backtraces for build dependencies, set the CARGO_PROFILE_DEV_BUILD_OVERRIDE_DEBUG=true environment variable to enable debug information generation.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/target/debug/build/nix-exprc-sys-1523a4712249c508/build-script-build` (exit status: 101)
[INFO] [stderr]   --- stdout
[INFO] [stderr]   cargo:rerun-if-env-changed=NIX_EXPR_C_NO_PKG_CONFIG
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_PATH_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_PATH_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG_PATH
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_PATH
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_LIBDIR_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_LIBDIR_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG_LIBDIR
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_LIBDIR
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_SYSROOT_DIR_x86_64-unknown-linux-gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_SYSROOT_DIR_x86_64_unknown_linux_gnu
[INFO] [stderr]   cargo:rerun-if-env-changed=HOST_PKG_CONFIG_SYSROOT_DIR
[INFO] [stderr]   cargo:rerun-if-env-changed=PKG_CONFIG_SYSROOT_DIR
[INFO] [stderr] 
[INFO] [stderr]   --- stderr
[INFO] [stderr] 
[INFO] [stderr]   thread 'main' (767) panicked at /opt/rustwide/workdir/common-build/src/lib.rs:35:10:
[INFO] [stderr]   called `Result::unwrap()` on an `Err` value: 
[INFO] [stderr]   pkg-config exited with status code 1
[INFO] [stderr]   > PKG_CONFIG_ALLOW_SYSTEM_LIBS=1 PKG_CONFIG_ALLOW_SYSTEM_CFLAGS=1 pkg-config --libs --cflags nix-expr-c
[INFO] [stderr] 
[INFO] [stderr]   The system library `nix-expr-c` required by crate `nix-exprc-sys` was not found.
[INFO] [stderr]   The file `nix-expr-c.pc` needs to be installed and the PKG_CONFIG_PATH environment variable must contain its parent directory.
[INFO] [stderr]   The PKG_CONFIG_PATH environment variable is not set.
[INFO] [stderr] 
[INFO] [stderr]   HINT: if you have installed the library, try setting PKG_CONFIG_PATH to the directory containing `nix-expr-c.pc`.
[INFO] [stderr] 
[INFO] [stderr]   stack backtrace:
[INFO] [stderr]      0:     0x628a37a8f542 - std::backtrace_rs::backtrace::libunwind::trace::h11a8b35bc44a0431
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
[INFO] [stderr]      1:     0x628a37a8f542 - std::backtrace_rs::backtrace::trace_unsynchronized::h4bb43ab1f2500e57
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
[INFO] [stderr]      2:     0x628a37a8f542 - std::sys::backtrace::_print_fmt::h4f91d56a36bf229c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:66:9
[INFO] [stderr]      3:     0x628a37a8f542 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h679c418ba9518ec2
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:39:26
[INFO] [stderr]      4:     0x628a37aa071f - core::fmt::rt::Argument::fmt::hbeaee41c05518475
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/fmt/rt.rs:173:76
[INFO] [stderr]      5:     0x628a37aa071f - core::fmt::write::h51c66197b4d957a8
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/fmt/mod.rs:1469:25
[INFO] [stderr]      6:     0x628a37a60473 - std::io::default_write_fmt::h94cc754f3fb194d4
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/io/mod.rs:639:11
[INFO] [stderr]      7:     0x628a37a60473 - std::io::Write::write_fmt::hd7f9b346821f104c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/io/mod.rs:1954:13
[INFO] [stderr]      8:     0x628a37a6b1c2 - std::sys::backtrace::BacktraceLock::print::hc4c7ea61c5866868
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:42:9
[INFO] [stderr]      9:     0x628a37a6e34f - std::panicking::default_hook::{{closure}}::hb732ad1ff6e3a117
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:301:27
[INFO] [stderr]     10:     0x628a37a6e1a9 - std::panicking::default_hook::h6de8725131d88596
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:328:9
[INFO] [stderr]     11:     0x628a37a6e9d5 - std::panicking::panic_with_hook::h7a4b874e601515d2
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:834:13
[INFO] [stderr]     12:     0x628a37a6e7ba - std::panicking::panic_handler::{{closure}}::hdf12a7672c151d02
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:707:13
[INFO] [stderr]     13:     0x628a37a6b309 - std::sys::backtrace::__rust_end_short_backtrace::hec84a34dd67d028d
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/sys/backtrace.rs:174:18
[INFO] [stderr]     14:     0x628a37a53b7d - __rustc[7bfeb0a5f9a695b4]::rust_begin_unwind
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:698:5
[INFO] [stderr]     15:     0x628a37aaa550 - core::panicking::panic_fmt::h1043a43e4c4e7b8a
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/panicking.rs:80:14
[INFO] [stderr]     16:     0x628a37aa97b6 - core::result::unwrap_failed::hea0b4eefefc9a5d3
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/result.rs:1862:5
[INFO] [stderr]     17:     0x628a374dd6ed - nix_sys_common_build::configure_library::hf66c037da3cf87af
[INFO] [stderr]     18:     0x628a374dcb61 - build_script_build::main::h3dcfd79d06780344
[INFO] [stderr]     19:     0x628a374df263 - core::ops::function::FnOnce::call_once::ha0e6a67eca328899
[INFO] [stderr]     20:     0x628a374df026 - std::sys::backtrace::__rust_begin_short_backtrace::hf7275fd0c43342fe
[INFO] [stderr]     21:     0x628a374defb9 - std::rt::lang_start::{{closure}}::h5b5dbf6497e1c3de
[INFO] [stderr]     22:     0x628a37a61d10 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::he4713d5f5b5fad00
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/core/src/ops/function.rs:287:21
[INFO] [stderr]     23:     0x628a37a61d10 - std::panicking::catch_unwind::do_call::hc3ddf565c1f4dde0
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:590:40
[INFO] [stderr]     24:     0x628a37a61d10 - std::panicking::catch_unwind::hb9d05085c95f548e
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:553:19
[INFO] [stderr]     25:     0x628a37a61d10 - std::panic::catch_unwind::h0f5c787d106c8c09
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panic.rs:359:14
[INFO] [stderr]     26:     0x628a37a61d10 - std::rt::lang_start_internal::{{closure}}::h433b499d119da066
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/rt.rs:175:24
[INFO] [stderr]     27:     0x628a37a61d10 - std::panicking::catch_unwind::do_call::hbcdd02e26d5b172c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:590:40
[INFO] [stderr]     28:     0x628a37a61d10 - std::panicking::catch_unwind::h537a562662b7132c
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panicking.rs:553:19
[INFO] [stderr]     29:     0x628a37a61d10 - std::panic::catch_unwind::h9c7c44034c3fe654
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/panic.rs:359:14
[INFO] [stderr]     30:     0x628a37a61d10 - std::rt::lang_start_internal::h0851b37a761fa7da
[INFO] [stderr]                                  at /rustc/d5419f1e97b90741d51841f800d3c697c662567d/library/std/src/rt.rs:171:5
[INFO] [stderr]     31:     0x628a374defa1 - std::rt::lang_start::he2eeeecbb5717b9a
[INFO] [stderr]     32:     0x628a374e1e45 - main
[INFO] [stderr]     33:     0x78826a12d1ca - <unknown>
[INFO] [stderr]     34:     0x78826a12d28b - __libc_start_main
[INFO] [stderr]     35:     0x628a374dc865 - _start
[INFO] [stderr]     36:                0x0 - <unknown>
[INFO] running `Command { std: "docker" "inspect" "1efe1a05b18cbd47e9298e445b7d57a4df9b73c10c64b8f99682cc48e1e09338", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1efe1a05b18cbd47e9298e445b7d57a4df9b73c10c64b8f99682cc48e1e09338", kill_on_drop: false }`
[INFO] [stdout] 1efe1a05b18cbd47e9298e445b7d57a4df9b73c10c64b8f99682cc48e1e09338
