Vendor dependenciesvendor

Just testing how CI works with this. I tend to prefer vendoring, as it
means that if you have a copy of the code *you can always build it*.
Even if you're 20 years in the future

This is the output of

```
cargo vendor --versioned-dirs
```

11 files changed, 1516 insertions, 0 deletions

diff --git a/vendor/pkg-config-0.3.19/.cargo-checksum.json b/vendor/pkg-config-0.3.19/.cargo-checksum.json
new file mode 100644
index 00000000..057ed979
--- /dev/null
+++ b/vendor/pkg-config-0.3.19/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"CHANGELOG.md":"76c3cdc468bd39843de5ed2e5d11cc2de3e2fa3cc099dd3137722105f94c8557","Cargo.toml":"a575e9c8b92c4b29fbf7bb4add0e77ec99464e3ae9248d42c5162e948ffa914d","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"378f5840b258e2779c39418f3f2d7b2ba96f1c7917dd6be0713f88305dbda397","README.md":"1e22446920533dea171fea3951cb4cf8db34bd4dd6414b688720410a9c414d3c","src/lib.rs":"cecbf5f9c982e21cba0391a4d73ad9aab10a0fbfcfcbb3bab4ecb05ee9467e32","tests/escape.pc":"00caa4136799dbe5bd504239ba90d1156c12def365c8d761da319fe8a83b398e","tests/foo.pc":"4a1c442c5d1c10761ea1644f8fd58f93cc5a706391bc67b04c243bbd35d70d79","tests/framework.pc":"304fdb6cea92973650e410ab1f70ce1ebeb7718af3f139e806efbf182acd565c","tests/test.rs":"5ed13fc28a1853d20d27798819a1228673cb1e57097951dbb892e51327a21adb"},"package":"3831453b3449ceb48b6d9c7ad7c96d5ea673e9b470a1dc578c2ce6521230884c"}
\ No newline at end of file
diff --git a/vendor/pkg-config-0.3.19/CHANGELOG.md b/vendor/pkg-config-0.3.19/CHANGELOG.md
new file mode 100644
index 00000000..4a8e1883
--- /dev/null
+++ b/vendor/pkg-config-0.3.19/CHANGELOG.md
@@ -0,0 +1,103 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
+
+## [0.3.19] - 2020-10-13
+
+### Added
+
+- Add `README.md` to be displayed on crates.io (#111).
+
+- Support for `-isystem`, `-iquote` and `-idirafter` include flags (#115).
+
+### Changed
+
+- Improve documentation for cross-compilation (#113).
+
+- Allow overriding system root via the `PKG_CONFIG_SYSROOT_DIR` or `SYSROOT`
+  environment variable (#82).
+
+## [0.3.18] - 2020-07-11
+
+### Fixed
+
+- Use `env::var_os()` almost everywhere to handle non-UTF8 paths in
+  environment variables, and also improve error handling around environment
+  variable handling (#106).
+
+### Changed
+
+- Default the `env_metadata` build parameter to `true` instead of `false`.
+  Whenever a pkg-config related environment variable changes it would make
+  sense to rebuild crates that use pkg-config, or otherwise changes might not
+  be picked up. As such the previous default didn't make much sense (#105).
+
+## [0.3.17] - 2019-11-02
+
+### Fixed
+
+- Fix support for multiple version number constraints (#95)
+
+## [0.3.16] - 2019-09-09
+
+### Changed
+- Stop using deprecated functions and require Rust 1.30 (#84)
+
+### Fixed
+- Fix repository URL in README.md
+- Fix various clippy warnings
+
+### Added
+- Run `cargo fmt` as part of the CI (#89)
+- Derive `Clone` for `Library` and `Debug` for `Config (#91)
+- Add support for `PKG_CONFIG_ALLOW_SYSTEM_CFLAGS` and enable by default (#93)
+
+## [0.3.15] - 2019-07-25
+
+### Changed
+- Changes minimum documented rust version to 1.28 (#76)
+
+### Fixed
+- Fix Travis CI badge url (#78)
+- Fix project name in README.md (#81)
+
+### Added
+- Support specifying range of versions (#75)
+- Allow cross-compilation if pkg-config is customized (#44, #86)
+
+## [0.3.14] - 2018-08-28
+
+### Fixed
+- Don't append .lib suffix on MSVC builds (#72)
+
+## [0.3.13] - 2018-08-06
+
+### Fixed
+- Fix MSVC support to actually work and consider library paths too (#71)
+
+## [0.3.12] - 2018-06-18
+
+### Added
+- Support for MSVC (#70)
+- Document and test Rust 1.13 as minimally supported version (#66)
+
+## [0.3.11] - 2018-04-24
+
+### Fixed
+- Re-added AsciiExt import (#65)
+
+## [0.3.10] - 2018-04-23
+
+### Added
+- Allow static linking of /usr/ on macOS (#42)
+- Add support for parsing `-Wl,` style framework flags (#48)
+- Parse defines in `pkg-config` output (#49)
+- Rerun on `PKG_CONFIG_PATH` changes (#50)
+- Introduce target-scoped variables (#58)
+- Respect pkg-config escaping rules used with --cflags and --libs (#61)
+
+### Changed
+- Use `?` instead of `try!()` in the codebase (#63)
diff --git a/vendor/pkg-config-0.3.19/Cargo.toml b/vendor/pkg-config-0.3.19/Cargo.toml
new file mode 100644
index 00000000..ef5a159b
--- /dev/null
+++ b/vendor/pkg-config-0.3.19/Cargo.toml
@@ -0,0 +1,26 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+name = "pkg-config"
+version = "0.3.19"
+authors = ["Alex Crichton <alex@alexcrichton.com>"]
+description = "A library to run the pkg-config system tool at build time in order to be used in\nCargo build scripts.\n"
+documentation = "https://docs.rs/pkg-config"
+readme = "README.md"
+keywords = ["build-dependencies"]
+license = "MIT/Apache-2.0"
+repository = "https://github.com/rust-lang/pkg-config-rs"
+[dev-dependencies.lazy_static]
+version = "1"
+[badges.travis-ci]
+repository = "rust-lang/pkg-config-rs"
diff --git a/vendor/pkg-config-0.3.19/LICENSE-APACHE b/vendor/pkg-config-0.3.19/LICENSE-APACHE
new file mode 100644
index 00000000..16fe87b0
--- /dev/null
+++ b/vendor/pkg-config-0.3.19/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
+                        Version 2.0, January 2004
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+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+Copyright [yyyy] [name of copyright owner]
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+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
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diff --git a/vendor/pkg-config-0.3.19/LICENSE-MIT b/vendor/pkg-config-0.3.19/LICENSE-MIT
new file mode 100644
index 00000000..39e0ed66
--- /dev/null
+++ b/vendor/pkg-config-0.3.19/LICENSE-MIT
@@ -0,0 +1,25 @@
+Copyright (c) 2014 Alex Crichton
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/vendor/pkg-config-0.3.19/README.md b/vendor/pkg-config-0.3.19/README.md
new file mode 100644
index 00000000..3d8d2b04
--- /dev/null
+++ b/vendor/pkg-config-0.3.19/README.md
@@ -0,0 +1,79 @@
+# pkg-config-rs
+
+[![Build Status](https://travis-ci.com/rust-lang/pkg-config-rs.svg?branch=master)](https://travis-ci.com/rust-lang/pkg-config-rs)
+[![Rust](https://img.shields.io/badge/rust-1.30%2B-blue.svg?maxAge=3600)](https://github.com/rust-lang/pkg-config-rs/)
+
+[Documentation](https://docs.rs/pkg-config)
+
+A simple library meant to be used as a build dependency with Cargo packages in
+order to use the system `pkg-config` tool (if available) to determine where a
+library is located.
+
+You can use this crate directly to probe for specific libraries, or use
+[metadeps](https://github.com/joshtriplett/metadeps) to declare all your
+`pkg-config` dependencies in `Cargo.toml`.
+
+This library requires Rust 1.30+.
+
+# Example
+
+Find the system library named `foo`, with minimum version 1.2.3:
+
+```rust
+extern crate pkg_config;
+
+fn main() {
+    pkg_config::Config::new().atleast_version("1.2.3").probe("foo").unwrap();
+}
+```
+
+Find the system library named `foo`, with no version requirement (not
+recommended):
+
+```rust
+extern crate pkg_config;
+
+fn main() {
+    pkg_config::probe_library("foo").unwrap();
+}
+```
+
+# External configuration via target-scoped environment variables
+
+In cross-compilation context, it is useful to manage separately `PKG_CONFIG_PATH`
+and a few other variables for the `host` and the `target` platform.
+
+The supported variables are: `PKG_CONFIG_PATH`, `PKG_CONFIG_LIBDIR`, and
+`PKG_CONFIG_SYSROOT_DIR`.
+
+Each of these variables can also be supplied with certain prefixes and suffixes, in the following prioritized order:
+
+1. `<var>_<target>` - for example, `PKG_CONFIG_PATH_x86_64-unknown-linux-gnu`
+2. `<var>_<target_with_underscores>` - for example, `PKG_CONFIG_PATH_x86_64_unknown_linux_gnu`
+3. `<build-kind>_<var>` - for example, `HOST_PKG_CONFIG_PATH` or `TARGET_PKG_CONFIG_PATH`
+4. `<var>` - a plain `PKG_CONFIG_PATH`
+
+This crate will allow `pkg-config` to be used in cross-compilation
+if `PKG_CONFIG_SYSROOT_DIR` or `PKG_CONFIG` is set. You can set `PKG_CONFIG_ALLOW_CROSS=1`
+to bypass the compatibility check, but please note that enabling use of `pkg-config` in
+cross-compilation without appropriate sysroot and search paths set is likely to break builds.
+
+Some Rust sys crates support building vendored libraries from source, which may be a work
+around for lack of cross-compilation support in `pkg-config`.
+
+# License
+
+This project is licensed under either of
+
+ * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
+   http://www.apache.org/licenses/LICENSE-2.0)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or
+   http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in pkg-config-rs by you, as defined in the Apache-2.0 license, shall be
+dual licensed as above, without any additional terms or conditions.
diff --git a/vendor/pkg-config-0.3.19/src/lib.rs b/vendor/pkg-config-0.3.19/src/lib.rs
new file mode 100644
index 00000000..d9574dc0
--- /dev/null
+++ b/vendor/pkg-config-0.3.19/src/lib.rs
@@ -0,0 +1,731 @@
+//! A build dependency for Cargo libraries to find system artifacts through the
+//! `pkg-config` utility.
+//!
+//! This library will shell out to `pkg-config` as part of build scripts and
+//! probe the system to determine how to link to a specified library. The
+//! `Config` structure serves as a method of configuring how `pkg-config` is
+//! invoked in a builder style.
+//!
+//! A number of environment variables are available to globally configure how
+//! this crate will invoke `pkg-config`:
+//!
+//! * `FOO_NO_PKG_CONFIG` - if set, this will disable running `pkg-config` when
+//!   probing for the library named `foo`.
+//!
+//! * `PKG_CONFIG_ALLOW_CROSS` - The `pkg-config` command usually doesn't
+//!   support cross-compilation, and this crate prevents it from selecting
+//!   incompatible versions of libraries.
+//!   Setting `PKG_CONFIG_ALLOW_CROSS=1` disables this protection, which is
+//!   likely to cause linking errors, unless `pkg-config` has been configured
+//!   to use appropriate sysroot and search paths for the target platform.
+//!
+//! There are also a number of environment variables which can configure how a
+//! library is linked to (dynamically vs statically). These variables control
+//! whether the `--static` flag is passed. Note that this behavior can be
+//! overridden by configuring explicitly on `Config`. The variables are checked
+//! in the following order:
+//!
+//! * `FOO_STATIC` - pass `--static` for the library `foo`
+//! * `FOO_DYNAMIC` - do not pass `--static` for the library `foo`
+//! * `PKG_CONFIG_ALL_STATIC` - pass `--static` for all libraries
+//! * `PKG_CONFIG_ALL_DYNAMIC` - do not pass `--static` for all libraries
+//!
+//! After running `pkg-config` all appropriate Cargo metadata will be printed on
+//! stdout if the search was successful.
+//!
+//! # Example
+//!
+//! Find the system library named `foo`, with minimum version 1.2.3:
+//!
+//! ```no_run
+//! extern crate pkg_config;
+//!
+//! fn main() {
+//!     pkg_config::Config::new().atleast_version("1.2.3").probe("foo").unwrap();
+//! }
+//! ```
+//!
+//! Find the system library named `foo`, with no version requirement (not
+//! recommended):
+//!
+//! ```no_run
+//! extern crate pkg_config;
+//!
+//! fn main() {
+//!     pkg_config::probe_library("foo").unwrap();
+//! }
+//! ```
+//!
+//! Configure how library `foo` is linked to.
+//!
+//! ```no_run
+//! extern crate pkg_config;
+//!
+//! fn main() {
+//!     pkg_config::Config::new().atleast_version("1.2.3").statik(true).probe("foo").unwrap();
+//! }
+//! ```
+
+#![doc(html_root_url = "https://docs.rs/pkg-config/0.3")]
+
+use std::collections::HashMap;
+use std::env;
+use std::error;
+use std::ffi::{OsStr, OsString};
+use std::fmt;
+use std::io;
+use std::ops::{Bound, RangeBounds};
+use std::path::PathBuf;
+use std::process::{Command, Output};
+use std::str;
+
+#[derive(Clone, Debug)]
+pub struct Config {
+    statik: Option<bool>,
+    min_version: Bound<String>,
+    max_version: Bound<String>,
+    extra_args: Vec<OsString>,
+    cargo_metadata: bool,
+    env_metadata: bool,
+    print_system_libs: bool,
+    print_system_cflags: bool,
+}
+
+#[derive(Clone, Debug)]
+pub struct Library {
+    pub libs: Vec<String>,
+    pub link_paths: Vec<PathBuf>,
+    pub frameworks: Vec<String>,
+    pub framework_paths: Vec<PathBuf>,
+    pub include_paths: Vec<PathBuf>,
+    pub defines: HashMap<String, Option<String>>,
+    pub version: String,
+    _priv: (),
+}
+
+/// Represents all reasons `pkg-config` might not succeed or be run at all.
+#[derive(Debug)]
+pub enum Error {
+    /// Aborted because of `*_NO_PKG_CONFIG` environment variable.
+    ///
+    /// Contains the name of the responsible environment variable.
+    EnvNoPkgConfig(String),
+
+    /// Detected cross compilation without a custom sysroot.
+    ///
+    /// Ignore the error with `PKG_CONFIG_ALLOW_CROSS=1`,
+    /// which may let `pkg-config` select libraries
+    /// for the host's architecture instead of the target's.
+    CrossCompilation,
+
+    /// Failed to run `pkg-config`.
+    ///
+    /// Contains the command and the cause.
+    Command { command: String, cause: io::Error },
+
+    /// `pkg-config` did not exit sucessfully.
+    ///
+    /// Contains the command and output.
+    Failure { command: String, output: Output },
+
+    #[doc(hidden)]
+    // please don't match on this, we're likely to add more variants over time
+    __Nonexhaustive,
+}
+
+impl error::Error for Error {}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        match *self {
+            Error::EnvNoPkgConfig(ref name) => write!(f, "Aborted because {} is set", name),
+            Error::CrossCompilation => f.write_str(
+                "pkg-config has not been configured to support cross-compilation.
+
+                Install a sysroot for the target platform and configure it via
+                PKG_CONFIG_SYSROOT_DIR and PKG_CONFIG_PATH, or install a
+                cross-compiling wrapper for pkg-config and set it via
+                PKG_CONFIG environment variable.",
+            ),
+            Error::Command {
+                ref command,
+                ref cause,
+            } => write!(f, "Failed to run `{}`: {}", command, cause),
+            Error::Failure {
+                ref command,
+                ref output,
+            } => {
+                let stdout = str::from_utf8(&output.stdout).unwrap();
+                let stderr = str::from_utf8(&output.stderr).unwrap();
+                write!(
+                    f,
+                    "`{}` did not exit successfully: {}",
+                    command, output.status
+                )?;
+                if !stdout.is_empty() {
+                    write!(f, "\n--- stdout\n{}", stdout)?;
+                }
+                if !stderr.is_empty() {
+                    write!(f, "\n--- stderr\n{}", stderr)?;
+                }
+                Ok(())
+            }
+            Error::__Nonexhaustive => panic!(),
+        }
+    }
+}
+
+/// Deprecated in favor of the probe_library function
+#[doc(hidden)]
+pub fn find_library(name: &str) -> Result<Library, String> {
+    probe_library(name).map_err(|e| e.to_string())
+}
+
+/// Simple shortcut for using all default options for finding a library.
+pub fn probe_library(name: &str) -> Result<Library, Error> {
+    Config::new().probe(name)
+}
+
+/// Run `pkg-config` to get the value of a variable from a package using
+/// `--variable`.
+///
+/// The content of `PKG_CONFIG_SYSROOT_DIR` is not injected in paths that are
+/// returned by `pkg-config --variable`, which makes them unsuitable to use
+/// during cross-compilation unless specifically designed to be used
+/// at that time.
+pub fn get_variable(package: &str, variable: &str) -> Result<String, Error> {
+    let arg = format!("--variable={}", variable);
+    let cfg = Config::new();
+    let out = run(cfg.command(package, &[&arg]))?;
+    Ok(str::from_utf8(&out).unwrap().trim_end().to_owned())
+}
+
+impl Config {
+    /// Creates a new set of configuration options which are all initially set
+    /// to "blank".
+    pub fn new() -> Config {
+        Config {
+            statik: None,
+            min_version: Bound::Unbounded,
+            max_version: Bound::Unbounded,
+            extra_args: vec![],
+            print_system_cflags: true,
+            print_system_libs: true,
+            cargo_metadata: true,
+            env_metadata: true,
+        }
+    }
+
+    /// Indicate whether the `--static` flag should be passed.
+    ///
+    /// This will override the inference from environment variables described in
+    /// the crate documentation.
+    pub fn statik(&mut self, statik: bool) -> &mut Config {
+        self.statik = Some(statik);
+        self
+    }
+
+    /// Indicate that the library must be at least version `vers`.
+    pub fn atleast_version(&mut self, vers: &str) -> &mut Config {
+        self.min_version = Bound::Included(vers.to_string());
+        self.max_version = Bound::Unbounded;
+        self
+    }
+
+    /// Indicate that the library must be equal to version `vers`.
+    pub fn exactly_version(&mut self, vers: &str) -> &mut Config {
+        self.min_version = Bound::Included(vers.to_string());
+        self.max_version = Bound::Included(vers.to_string());
+        self
+    }
+
+    /// Indicate that the library's version must be in `range`.
+    pub fn range_version<'a, R>(&mut self, range: R) -> &mut Config
+    where
+        R: RangeBounds<&'a str>,
+    {
+        self.min_version = match range.start_bound() {
+            Bound::Included(vers) => Bound::Included(vers.to_string()),
+            Bound::Excluded(vers) => Bound::Excluded(vers.to_string()),
+            Bound::Unbounded => Bound::Unbounded,
+        };
+        self.max_version = match range.end_bound() {
+            Bound::Included(vers) => Bound::Included(vers.to_string()),
+            Bound::Excluded(vers) => Bound::Excluded(vers.to_string()),
+            Bound::Unbounded => Bound::Unbounded,
+        };
+        self
+    }
+
+    /// Add an argument to pass to pkg-config.
+    ///
+    /// It's placed after all of the arguments generated by this library.
+    pub fn arg<S: AsRef<OsStr>>(&mut self, arg: S) -> &mut Config {
+        self.extra_args.push(arg.as_ref().to_os_string());
+        self
+    }
+
+    /// Define whether metadata should be emitted for cargo allowing it to
+    /// automatically link the binary. Defaults to `true`.
+    pub fn cargo_metadata(&mut self, cargo_metadata: bool) -> &mut Config {
+        self.cargo_metadata = cargo_metadata;
+        self
+    }
+
+    /// Define whether metadata should be emitted for cargo allowing to
+    /// automatically rebuild when environment variables change. Defaults to
+    /// `true`.
+    pub fn env_metadata(&mut self, env_metadata: bool) -> &mut Config {
+        self.env_metadata = env_metadata;
+        self
+    }
+
+    /// Enable or disable the `PKG_CONFIG_ALLOW_SYSTEM_LIBS` environment
+    /// variable.
+    ///
+    /// This env var is enabled by default.
+    pub fn print_system_libs(&mut self, print: bool) -> &mut Config {
+        self.print_system_libs = print;
+        self
+    }
+
+    /// Enable or disable the `PKG_CONFIG_ALLOW_SYSTEM_CFLAGS` environment
+    /// variable.
+    ///
+    /// This env var is enabled by default.
+    pub fn print_system_cflags(&mut self, print: bool) -> &mut Config {
+        self.print_system_cflags = print;
+        self
+    }
+
+    /// Deprecated in favor fo the `probe` function
+    #[doc(hidden)]
+    pub fn find(&self, name: &str) -> Result<Library, String> {
+        self.probe(name).map_err(|e| e.to_string())
+    }
+
+    /// Run `pkg-config` to find the library `name`.
+    ///
+    /// This will use all configuration previously set to specify how
+    /// `pkg-config` is run.
+    pub fn probe(&self, name: &str) -> Result<Library, Error> {
+        let abort_var_name = format!("{}_NO_PKG_CONFIG", envify(name));
+        if self.env_var_os(&abort_var_name).is_some() {
+            return Err(Error::EnvNoPkgConfig(abort_var_name));
+        } else if !self.target_supported() {
+            return Err(Error::CrossCompilation);
+        }
+
+        let mut library = Library::new();
+
+        let output = run(self.command(name, &["--libs", "--cflags"]))?;
+        library.parse_libs_cflags(name, &output, self);
+