Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

6 files changed, 1078 insertions, 0 deletions

diff --git a/src/tools/clippy/lintcheck/Cargo.toml b/src/tools/clippy/lintcheck/Cargo.toml
new file mode 100644
index 000000000..737c845c0
--- /dev/null
+++ b/src/tools/clippy/lintcheck/Cargo.toml
@@ -0,0 +1,24 @@
+[package]
+name = "lintcheck"
+version = "0.0.1"
+description = "tool to monitor impact of changes in Clippy's lints on a part of the ecosystem"
+readme = "README.md"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/rust-clippy"
+categories = ["development-tools"]
+edition = "2021"
+publish = false
+
+[dependencies]
+cargo_metadata = "0.14"
+clap = "3.2"
+flate2 = "1.0"
+rayon = "1.5.1"
+serde = { version = "1.0", features = ["derive"] }
+tar = "0.4"
+toml = "0.5"
+ureq = "2.2"
+walkdir = "2.3"
+
+[features]
+deny-warnings = []
diff --git a/src/tools/clippy/lintcheck/README.md b/src/tools/clippy/lintcheck/README.md
new file mode 100644
index 000000000..6f3d23382
--- /dev/null
+++ b/src/tools/clippy/lintcheck/README.md
@@ -0,0 +1,77 @@
+## `cargo lintcheck`
+
+Runs clippy on a fixed set of crates read from
+`lintcheck/lintcheck_crates.toml` and saves logs of the lint warnings into the
+repo.  We can then check the diff and spot new or disappearing warnings.
+
+From the repo root, run:
+
+```
+cargo run --target-dir lintcheck/target --manifest-path lintcheck/Cargo.toml
+```
+
+or
+
+```
+cargo lintcheck
+```
+
+By default the logs will be saved into
+`lintcheck-logs/lintcheck_crates_logs.txt`.
+
+You can set a custom sources.toml by adding `--crates-toml custom.toml` or using
+`LINTCHECK_TOML="custom.toml"` where `custom.toml` must be a relative path from
+the repo root.
+
+The results will then be saved to `lintcheck-logs/custom_logs.toml`.
+
+### Configuring the Crate Sources
+
+The sources to check are saved in a `toml` file. There are three types of
+sources.
+
+1. Crates-io Source
+
+   ```toml
+   bitflags = {name = "bitflags", versions = ['1.2.1']}
+   ```
+   Requires a "name" and one or multiple "versions" to be checked.
+
+2. `git` Source
+   ````toml
+   puffin = {name = "puffin", git_url = "https://github.com/EmbarkStudios/puffin", git_hash = "02dd4a3"}
+   ````
+   Requires a name, the url to the repo and unique identifier of a commit,
+   branch or tag which is checked out before linting.  There is no way to always
+   check `HEAD` because that would lead to changing lint-results as the repo
+   would get updated.  If `git_url` or `git_hash` is missing, an error will be
+   thrown.
+
+3. Local Dependency
+   ```toml
+   clippy = {name = "clippy", path = "/home/user/clippy"}
+   ```
+   For when you want to add a repository that is not published yet.
+
+#### Command Line Options (optional)
+
+```toml
+bitflags = {name = "bitflags", versions = ['1.2.1'], options = ['-Wclippy::pedantic', '-Wclippy::cargo']}
+```
+
+It is possible to specify command line options for each crate. This makes it
+possible to only check a crate for certain lint groups. If no options are
+specified, the lint groups `clippy::all`, `clippy::pedantic`, and
+`clippy::cargo` are checked. If an empty array is specified only `clippy::all`
+is checked.
+
+**Note:** `-Wclippy::all` is always enabled by default, unless `-Aclippy::all`
+is explicitly specified in the options.
+
+### Fix mode
+You can run `./lintcheck/target/debug/lintcheck --fix` which will run Clippy with `--fix` and
+print a warning if Clippy's suggestions fail to apply (if the resulting code does not build).  
+This lets us spot bad suggestions or false positives automatically in some cases.  
+
+Please note that the target dir should be cleaned afterwards since clippy will modify
+the downloaded sources which can lead to unexpected results when running lintcheck again afterwards.
diff --git a/src/tools/clippy/lintcheck/lintcheck_crates.toml b/src/tools/clippy/lintcheck/lintcheck_crates.toml
new file mode 100644
index 000000000..4fbae8614
--- /dev/null
+++ b/src/tools/clippy/lintcheck/lintcheck_crates.toml
@@ -0,0 +1,35 @@
+[crates]
+# some of these are from cargotest
+cargo = {name = "cargo", versions = ['0.49.0']}
+iron = {name = "iron", versions = ['0.6.1']}
+ripgrep = {name = "ripgrep", versions = ['12.1.1']}
+xsv = {name = "xsv", versions = ['0.13.0']}
+# commented out because of 173K clippy::match_same_arms msgs in language_type.rs
+#tokei = { name = "tokei", versions = ['12.0.4']}
+rayon = {name = "rayon", versions = ['1.5.0']}
+serde = {name = "serde", versions = ['1.0.118']}
+# top 10 crates.io dls
+bitflags = {name = "bitflags", versions = ['1.2.1']}
+# crash = {name = "clippy_crash", path = "/tmp/clippy_crash"}
+libc = {name = "libc", versions = ['0.2.81']}
+log = {name = "log", versions = ['0.4.11']}
+proc-macro2 = {name = "proc-macro2", versions = ['1.0.24']}
+quote = {name = "quote", versions = ['1.0.7']}
+rand = {name = "rand", versions = ['0.7.3']}
+rand_core = {name = "rand_core", versions = ['0.6.0']}
+regex = {name = "regex", versions = ['1.3.2']}
+syn = {name = "syn", versions = ['1.0.54']}
+unicode-xid = {name = "unicode-xid", versions = ['0.2.1']}
+# some more of dtolnays crates
+anyhow = {name = "anyhow", versions = ['1.0.38']}
+async-trait = {name = "async-trait", versions = ['0.1.42']}
+cxx = {name = "cxx", versions = ['1.0.32']}
+ryu = {name = "ryu", versions = ['1.0.5']}
+serde_yaml = {name = "serde_yaml", versions = ['0.8.17']}
+thiserror = {name = "thiserror", versions = ['1.0.24']}
+# some embark crates, there are other interesting crates but
+# unfortunately adding them increases lintcheck runtime drastically
+cfg-expr = {name = "cfg-expr", versions = ['0.7.1']}
+puffin = {name = "puffin", git_url = "https://github.com/EmbarkStudios/puffin", git_hash = "02dd4a3"}
+rpmalloc = {name = "rpmalloc", versions = ['0.2.0']}
+tame-oidc = {name = "tame-oidc", versions = ['0.1.0']}
diff --git a/src/tools/clippy/lintcheck/src/config.rs b/src/tools/clippy/lintcheck/src/config.rs
new file mode 100644
index 000000000..1742cf677
--- /dev/null
+++ b/src/tools/clippy/lintcheck/src/config.rs
@@ -0,0 +1,124 @@
+use clap::{Arg, ArgAction, ArgMatches, Command};
+use std::env;
+use std::path::PathBuf;
+
+fn get_clap_config() -> ArgMatches {
+    Command::new("lintcheck")
+        .about("run clippy on a set of crates and check output")
+        .args([
+            Arg::new("only")
+                .action(ArgAction::Set)
+                .value_name("CRATE")
+                .long("only")
+                .help("Only process a single crate of the list"),
+            Arg::new("crates-toml")
+                .action(ArgAction::Set)
+                .value_name("CRATES-SOURCES-TOML-PATH")
+                .long("crates-toml")
+                .help("Set the path for a crates.toml where lintcheck should read the sources from"),
+            Arg::new("threads")
+                .action(ArgAction::Set)
+                .value_name("N")
+                .value_parser(clap::value_parser!(usize))
+                .short('j')
+                .long("jobs")
+                .help("Number of threads to use, 0 automatic choice"),
+            Arg::new("fix")
+                .long("fix")
+                .help("Runs cargo clippy --fix and checks if all suggestions apply"),
+            Arg::new("filter")
+                .long("filter")
+                .action(ArgAction::Append)
+                .value_name("clippy_lint_name")
+                .help("Apply a filter to only collect specified lints, this also overrides `allow` attributes"),
+            Arg::new("markdown")
+                .long("markdown")
+                .help("Change the reports table to use markdown links"),
+        ])
+        .get_matches()
+}
+
+#[derive(Debug)]
+pub(crate) struct LintcheckConfig {
+    /// max number of jobs to spawn (default 1)
+    pub max_jobs: usize,
+    /// we read the sources to check from here
+    pub sources_toml_path: PathBuf,
+    /// we save the clippy lint results here
+    pub lintcheck_results_path: PathBuf,
+    /// Check only a specified package
+    pub only: Option<String>,
+    /// whether to just run --fix and not collect all the warnings
+    pub fix: bool,
+    /// A list of lints that this lintcheck run should focus on
+    pub lint_filter: Vec<String>,
+    /// Indicate if the output should support markdown syntax
+    pub markdown: bool,
+}
+
+impl LintcheckConfig {
+    pub fn new() -> Self {
+        let clap_config = get_clap_config();
+
+        // first, check if we got anything passed via the LINTCHECK_TOML env var,
+        // if not, ask clap if we got any value for --crates-toml  <foo>
+        // if not, use the default "lintcheck/lintcheck_crates.toml"
+        let sources_toml = env::var("LINTCHECK_TOML").unwrap_or_else(|_| {
+            clap_config
+                .get_one::<String>("crates-toml")
+                .map(|s| &**s)
+                .unwrap_or("lintcheck/lintcheck_crates.toml")
+                .into()
+        });
+
+        let markdown = clap_config.contains_id("markdown");
+        let sources_toml_path = PathBuf::from(sources_toml);
+
+        // for the path where we save the lint results, get the filename without extension (so for
+        // wasd.toml, use "wasd"...)
+        let filename: PathBuf = sources_toml_path.file_stem().unwrap().into();
+        let lintcheck_results_path = PathBuf::from(format!(
+            "lintcheck-logs/{}_logs.{}",
+            filename.display(),
+            if markdown { "md" } else { "txt" }
+        ));
+
+        // look at the --threads arg, if 0 is passed, ask rayon rayon how many threads it would spawn and
+        // use half of that for the physical core count
+        // by default use a single thread
+        let max_jobs = match clap_config.get_one::<usize>("threads") {
+            Some(&0) => {
+                // automatic choice
+                // Rayon seems to return thread count so half that for core count
+                (rayon::current_num_threads() / 2) as usize
+            },
+            Some(&threads) => threads,
+            // no -j passed, use a single thread
+            None => 1,
+        };
+
+        let lint_filter: Vec<String> = clap_config
+            .get_many::<String>("filter")
+            .map(|iter| {
+                iter.map(|lint_name| {
+                    let mut filter = lint_name.replace('_', "-");
+                    if !filter.starts_with("clippy::") {
+                        filter.insert_str(0, "clippy::");
+                    }
+                    filter
+                })
+                .collect()
+            })
+            .unwrap_or_default();
+
+        LintcheckConfig {
+            max_jobs,
+            sources_toml_path,
+            lintcheck_results_path,
+            only: clap_config.get_one::<String>("only").map(String::from),
+            fix: clap_config.contains_id("fix"),
+            lint_filter,
+            markdown,
+        }
+    }
+}
diff --git a/src/tools/clippy/lintcheck/src/main.rs b/src/tools/clippy/lintcheck/src/main.rs
new file mode 100644
index 000000000..9ee25280f
--- /dev/null
+++ b/src/tools/clippy/lintcheck/src/main.rs
@@ -0,0 +1,814 @@
+// Run clippy on a fixed set of crates and collect the warnings.
+// This helps observing the impact clippy changes have on a set of real-world code (and not just our
+// testsuite).
+//
+// When a new lint is introduced, we can search the results for new warnings and check for false
+// positives.
+
+#![allow(clippy::collapsible_else_if)]
+
+mod config;
+
+use config::LintcheckConfig;
+
+use std::collections::HashMap;
+use std::env;
+use std::fmt::Write as _;
+use std::fs::write;
+use std::io::ErrorKind;
+use std::path::{Path, PathBuf};
+use std::process::Command;
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::thread;
+use std::time::Duration;
+
+use cargo_metadata::diagnostic::DiagnosticLevel;
+use cargo_metadata::Message;
+use rayon::prelude::*;
+use serde::{Deserialize, Serialize};
+use walkdir::{DirEntry, WalkDir};
+
+#[cfg(not(windows))]
+const CLIPPY_DRIVER_PATH: &str = "target/debug/clippy-driver";
+#[cfg(not(windows))]
+const CARGO_CLIPPY_PATH: &str = "target/debug/cargo-clippy";
+
+#[cfg(windows)]
+const CLIPPY_DRIVER_PATH: &str = "target/debug/clippy-driver.exe";
+#[cfg(windows)]
+const CARGO_CLIPPY_PATH: &str = "target/debug/cargo-clippy.exe";
+
+const LINTCHECK_DOWNLOADS: &str = "target/lintcheck/downloads";
+const LINTCHECK_SOURCES: &str = "target/lintcheck/sources";
+
+/// List of sources to check, loaded from a .toml file
+#[derive(Debug, Serialize, Deserialize)]
+struct SourceList {
+    crates: HashMap<String, TomlCrate>,
+}
+
+/// A crate source stored inside the .toml
+/// will be translated into on one of the `CrateSource` variants
+#[derive(Debug, Serialize, Deserialize)]
+struct TomlCrate {
+    name: String,
+    versions: Option<Vec<String>>,
+    git_url: Option<String>,
+    git_hash: Option<String>,
+    path: Option<String>,
+    options: Option<Vec<String>>,
+}
+
+/// Represents an archive we download from crates.io, or a git repo, or a local repo/folder
+/// Once processed (downloaded/extracted/cloned/copied...), this will be translated into a `Crate`
+#[derive(Debug, Serialize, Deserialize, Eq, Hash, PartialEq, Ord, PartialOrd)]
+enum CrateSource {
+    CratesIo {
+        name: String,
+        version: String,
+        options: Option<Vec<String>>,
+    },
+    Git {
+        name: String,
+        url: String,
+        commit: String,
+        options: Option<Vec<String>>,
+    },
+    Path {
+        name: String,
+        path: PathBuf,
+        options: Option<Vec<String>>,
+    },
+}
+
+/// Represents the actual source code of a crate that we ran "cargo clippy" on
+#[derive(Debug)]
+struct Crate {
+    version: String,
+    name: String,
+    // path to the extracted sources that clippy can check
+    path: PathBuf,
+    options: Option<Vec<String>>,
+}
+
+/// A single warning that clippy issued while checking a `Crate`
+#[derive(Debug)]
+struct ClippyWarning {
+    crate_name: String,
+    file: String,
+    line: usize,
+    column: usize,
+    lint_type: String,
+    message: String,
+    is_ice: bool,
+}
+
+#[allow(unused)]
+impl ClippyWarning {
+    fn new(cargo_message: Message, krate: &Crate) -> Option<Self> {
+        let diag = match cargo_message {
+            Message::CompilerMessage(message) => message.message,
+            _ => return None,
+        };
+
+        let lint_type = diag.code?.code;
+        if !(lint_type.contains("clippy") || diag.message.contains("clippy"))
+            || diag.message.contains("could not read cargo metadata")
+        {
+            return None;
+        }
+
+        let span = diag.spans.into_iter().find(|span| span.is_primary)?;
+
+        let file = match Path::new(&span.file_name).strip_prefix(env!("CARGO_HOME")) {
+            Ok(stripped) => format!("$CARGO_HOME/{}", stripped.display()),
+            Err(_) => format!(
+                "target/lintcheck/sources/{}-{}/{}",
+                krate.name, krate.version, span.file_name
+            ),
+        };
+
+        Some(Self {
+            crate_name: krate.name.clone(),
+            file,
+            line: span.line_start,
+            column: span.column_start,
+            lint_type,
+            message: diag.message,
+            is_ice: diag.level == DiagnosticLevel::Ice,
+        })
+    }
+
+    fn to_output(&self, markdown: bool) -> String {
+        let file_with_pos = format!("{}:{}:{}", &self.file, &self.line, &self.column);
+        if markdown {
+            let lint = format!("`{}`", self.lint_type);
+
+            let mut file = self.file.clone();
+            if !file.starts_with('$') {
+                file.insert_str(0, "../");
+            }
+
+            let mut output = String::from("| ");
+            let _ = write!(output, "[`{}`]({}#L{})", file_with_pos, file, self.line);
+            let _ = write!(output, r#" | {:<50} | "{}" |"#, lint, self.message);
+            output.push('\n');
+            output
+        } else {
+            format!("{} {} \"{}\"\n", file_with_pos, self.lint_type, self.message)
+        }
+    }
+}
+
+fn get(path: &str) -> Result<ureq::Response, ureq::Error> {
+    const MAX_RETRIES: u8 = 4;
+    let mut retries = 0;
+    loop {
+        match ureq::get(path).call() {
+            Ok(res) => return Ok(res),
+            Err(e) if retries >= MAX_RETRIES => return Err(e),
+            Err(ureq::Error::Transport(e)) => eprintln!("Error: {}", e),
+            Err(e) => return Err(e),
+        }
+        eprintln!("retrying in {} seconds...", retries);
+        thread::sleep(Duration::from_secs(retries as u64));
+        retries += 1;
+    }
+}
+
+impl CrateSource {
+    /// Makes the sources available on the disk for clippy to check.
+    /// Clones a git repo and checks out the specified commit or downloads a crate from crates.io or
+    /// copies a local folder
+    fn download_and_extract(&self) -> Crate {
+        match self {
+            CrateSource::CratesIo { name, version, options } => {
+                let extract_dir = PathBuf::from(LINTCHECK_SOURCES);
+                let krate_download_dir = PathBuf::from(LINTCHECK_DOWNLOADS);
+
+                // url to download the crate from crates.io
+                let url = format!("https://crates.io/api/v1/crates/{}/{}/download", name, version);
+                println!("Downloading and extracting {} {} from {}", name, version, url);
+                create_dirs(&krate_download_dir, &extract_dir);
+
+                let krate_file_path = krate_download_dir.join(format!("{}-{}.crate.tar.gz", name, version));
+                // don't download/extract if we already have done so
+                if !krate_file_path.is_file() {
+                    // create a file path to download and write the crate data into
+                    let mut krate_dest = std::fs::File::create(&krate_file_path).unwrap();
+                    let mut krate_req = get(&url).unwrap().into_reader();
+                    // copy the crate into the file
+                    std::io::copy(&mut krate_req, &mut krate_dest).unwrap();
+
+                    // unzip the tarball
+                    let ungz_tar = flate2::read::GzDecoder::new(std::fs::File::open(&krate_file_path).unwrap());
+                    // extract the tar archive
+                    let mut archive = tar::Archive::new(ungz_tar);
+                    archive.unpack(&extract_dir).expect("Failed to extract!");
+                }
+                // crate is extracted, return a new Krate object which contains the path to the extracted
+                // sources that clippy can check
+                Crate {
+                    version: version.clone(),
+                    name: name.clone(),
+                    path: extract_dir.join(format!("{}-{}/", name, version)),
+                    options: options.clone(),
+                }
+            },
+            CrateSource::Git {
+                name,
+                url,
+                commit,
+                options,
+            } => {
+                let repo_path = {
+                    let mut repo_path = PathBuf::from(LINTCHECK_SOURCES);
+                    // add a -git suffix in case we have the same crate from crates.io and a git repo
+                    repo_path.push(format!("{}-git", name));
+                    repo_path
+                };
+                // clone the repo if we have not done so
+                if !repo_path.is_dir() {
+                    println!("Cloning {} and checking out {}", url, commit);
+                    if !Command::new("git")
+                        .arg("clone")
+                        .arg(url)
+                        .arg(&repo_path)
+                        .status()
+                        .expect("Failed to clone git repo!")
+                        .success()
+                    {
+                        eprintln!("Failed to clone {} into {}", url, repo_path.display())
+                    }
+                }
+                // check out the commit/branch/whatever
+                if !Command::new("git")
+                    .arg("checkout")
+                    .arg(commit)
+                    .current_dir(&repo_path)
+                    .status()
+                    .expect("Failed to check out commit")
+                    .success()
+                {
+                    eprintln!("Failed to checkout {} of repo at {}", commit, repo_path.display())
+                }
+
+                Crate {
+                    version: commit.clone(),
+                    name: name.clone(),
+                    path: repo_path,
+                    options: options.clone(),
+                }
+            },
+            CrateSource::Path { name, path, options } => {
+                // copy path into the dest_crate_root but skip directories that contain a CACHEDIR.TAG file.
+                // The target/ directory contains a CACHEDIR.TAG file so it is the most commonly skipped directory
+                // as a result of this filter.
+                let dest_crate_root = PathBuf::from(LINTCHECK_SOURCES).join(name);
+                if dest_crate_root.exists() {
+                    println!("Deleting existing directory at {:?}", dest_crate_root);
+                    std::fs::remove_dir_all(&dest_crate_root).unwrap();
+                }
+
+                println!("Copying {:?} to {:?}", path, dest_crate_root);
+
+                fn is_cache_dir(entry: &DirEntry) -> bool {
+                    std::fs::read(entry.path().join("CACHEDIR.TAG"))
+                        .map(|x| x.starts_with(b"Signature: 8a477f597d28d172789f06886806bc55"))
+                        .unwrap_or(false)
+                }
+
+                for entry in WalkDir::new(path).into_iter().filter_entry(|e| !is_cache_dir(e)) {
+                    let entry = entry.unwrap();
+                    let entry_path = entry.path();
+                    let relative_entry_path = entry_path.strip_prefix(path).unwrap();
+                    let dest_path = dest_crate_root.join(relative_entry_path);
+                    let metadata = entry_path.symlink_metadata().unwrap();
+
+                    if metadata.is_dir() {
+                        std::fs::create_dir(dest_path).unwrap();
+                    } else if metadata.is_file() {
+                        std::fs::copy(entry_path, dest_path).unwrap();
+                    }
+                }
+
+                Crate {
+                    version: String::from("local"),
+                    name: name.clone(),
+                    path: dest_crate_root,
+                    options: options.clone(),
+                }
+            },
+        }
+    }
+}
+
+impl Crate {
+    /// Run `cargo clippy` on the `Crate` and collect and return all the lint warnings that clippy
+    /// issued
+    fn run_clippy_lints(
+        &self,
+        cargo_clippy_path: &Path,
+        target_dir_index: &AtomicUsize,
+        total_crates_to_lint: usize,
+        config: &LintcheckConfig,
+        lint_filter: &Vec<String>,
+    ) -> Vec<ClippyWarning> {
+        // advance the atomic index by one
+        let index = target_dir_index.fetch_add(1, Ordering::SeqCst);
+        // "loop" the index within 0..thread_limit
+        let thread_index = index % config.max_jobs;
+        let perc = (index * 100) / total_crates_to_lint;
+
+        if config.max_jobs == 1 {
+            println!(
+                "{}/{} {}% Linting {} {}",
+                index, total_crates_to_lint, perc, &self.name, &self.version
+            );
+        } else {
+            println!(
+                "{}/{} {}% Linting {} {} in target dir {:?}",
+                index, total_crates_to_lint, perc, &self.name, &self.version, thread_index
+            );
+        }
+
+        let cargo_clippy_path = std::fs::canonicalize(cargo_clippy_path).unwrap();
+
+        let shared_target_dir = clippy_project_root().join("target/lintcheck/shared_target_dir");
+
+        let mut args = if config.fix {
+            vec!["--fix", "--"]
+        } else {
+            vec!["--", "--message-format=json", "--"]
+        };
+
+        if let Some(options) = &self.options {
+            for opt in options {
+                args.push(opt);
+            }
+        } else {
+            args.extend(&["-Wclippy::pedantic", "-Wclippy::cargo"])
+        }
+
+        if lint_filter.is_empty() {
+            args.push("--cap-lints=warn");
+        } else {
+            args.push("--cap-lints=allow");
+            args.extend(lint_filter.iter().map(|filter| filter.as_str()))
+        }
+
+        let all_output = std::process::Command::new(&cargo_clippy_path)
+            // use the looping index to create individual target dirs
+            .env(
+                "CARGO_TARGET_DIR",
+                shared_target_dir.join(format!("_{:?}", thread_index)),
+            )
+            // lint warnings will look like this:
+            // src/cargo/ops/cargo_compile.rs:127:35: warning: usage of `FromIterator::from_iter`
+            .args(&args)
+            .current_dir(&self.path)
+            .output()
+            .unwrap_or_else(|error| {
+                panic!(
+                    "Encountered error:\n{:?}\ncargo_clippy_path: {}\ncrate path:{}\n",
+                    error,
+                    &cargo_clippy_path.display(),
+                    &self.path.display()
+                );
+            });
+        let stdout = String::from_utf8_lossy(&all_output.stdout);
+        let stderr = String::from_utf8_lossy(&all_output.stderr);
+        let status = &all_output.status;
+
+        if !status.success() {
+            eprintln!(
+                "\nWARNING: bad exit status after checking {} {} \n",
+                self.name, self.version
+            );
+        }
+
+        if config.fix {
+            if let Some(stderr) = stderr
+                .lines()
+                .find(|line| line.contains("failed to automatically apply fixes suggested by rustc to crate"))
+            {
+                let subcrate = &stderr[63..];
+                println!(
+                    "ERROR: failed to apply some suggetion to {} / to (sub)crate {}",
+                    self.name, subcrate
+                );
+            }
+            // fast path, we don't need the warnings anyway
+            return Vec::new();
+        }
+
+        // get all clippy warnings and ICEs
+        let warnings: Vec<ClippyWarning> = Message::parse_stream(stdout.as_bytes())
+            .filter_map(|msg| ClippyWarning::new(msg.unwrap(), &self))
+            .collect();
+
+        warnings
+    }
+}
+
+/// Builds clippy inside the repo to make sure we have a clippy executable we can use.
+fn build_clippy() {
+    let status = Command::new("cargo")
+        .arg("build")
+        .status()
+        .expect("Failed to build clippy!");
+    if !status.success() {
+        eprintln!("Error: Failed to compile Clippy!");
+        std::process::exit(1);
+    }
+}
+
+/// Read a `toml` file and return a list of `CrateSources` that we want to check with clippy
+fn read_crates(toml_path: &Path) -> Vec<CrateSource> {
+    let toml_content: String =
+        std::fs::read_to_string(&toml_path).unwrap_or_else(|_| panic!("Failed to read {}", toml_path.display()));
+    let crate_list: SourceList =
+        toml::from_str(&toml_content).unwrap_or_else(|e| panic!("Failed to parse {}: \n{}", toml_path.display(), e));
+    // parse the hashmap of the toml file into a list of crates
+    let tomlcrates: Vec<TomlCrate> = crate_list
+        .crates
+        .into_iter()
+        .map(|(_cratename, tomlcrate)| tomlcrate)
+        .collect();
+
+    // flatten TomlCrates into CrateSources (one TomlCrates may represent several versions of a crate =>
+    // multiple Cratesources)
+    let mut crate_sources = Vec::new();
+    tomlcrates.into_iter().for_each(|tk| {
+        if let Some(ref path) = tk.path {
+            crate_sources.push(CrateSource::Path {
+                name: tk.name.clone(),
+                path: PathBuf::from(path),
+                options: tk.options.clone(),
+            });
+        } else if let Some(ref versions) = tk.versions {
+            // if we have multiple versions, save each one
+            versions.iter().for_each(|ver| {
+                crate_sources.push(CrateSource::CratesIo {
+                    name: tk.name.clone(),
+                    version: ver.to_string(),
+                    options: tk.options.clone(),
+                });
+            })
+        } else if tk.git_url.is_some() && tk.git_hash.is_some() {
+            // otherwise, we should have a git source
+            crate_sources.push(CrateSource::Git {
+                name: tk.name.clone(),
+                url: tk.git_url.clone().unwrap(),
+                commit: tk.git_hash.clone().unwrap(),
+                options: tk.options.clone(),
+            });
+        } else {
+            panic!("Invalid crate source: {tk:?}");
+        }
+
+        // if we have a version as well as a git data OR only one git data, something is funky
+        if tk.versions.is_some() && (tk.git_url.is_some() || tk.git_hash.is_some())
+            || tk.git_hash.is_some() != tk.git_url.is_some()
+        {
+            eprintln!("tomlkrate: {:?}", tk);
+            if tk.git_hash.is_some() != tk.git_url.is_some() {
+                panic!("Error: Encountered TomlCrate with only one of git_hash and git_url!");
+            }
+            if tk.path.is_some() && (tk.git_hash.is_some() || tk.versions.is_some()) {
+                panic!("Error: TomlCrate can only have one of 'git_.*', 'version' or 'path' fields");
+            }
+            unreachable!("Failed to translate TomlCrate into CrateSource!");
+        }
+    });
+    // sort the crates
+    crate_sources.sort();
+
+    crate_sources
+}
+
+/// Generate a short list of occurring lints-types and their count
+fn gather_stats(clippy_warnings: &[ClippyWarning]) -> (String, HashMap<&String, usize>) {
+    // count lint type occurrences
+    let mut counter: HashMap<&String, usize> = HashMap::new();
+    clippy_warnings
+        .iter()
+        .for_each(|wrn| *counter.entry(&wrn.lint_type).or_insert(0) += 1);
+
+    // collect into a tupled list for sorting
+    let mut stats: Vec<(&&String, &usize)> = counter.iter().map(|(lint, count)| (lint, count)).collect();
+    // sort by "000{count} {clippy::lintname}"
+    // to not have a lint with 200 and 2 warnings take the same spot
+    stats.sort_by_key(|(lint, count)| format!("{:0>4}, {}", count, lint));
+
+    let mut header = String::from("| lint                                               | count |\n");
+    header.push_str("| -------------------------------------------------- | ----- |\n");
+    let stats_string = stats
+        .iter()
+        .map(|(lint, count)| format!("| {:<50} |  {:>4} |\n", lint, count))
+        .fold(header, |mut table, line| {
+            table.push_str(&line);
+            table
+        });
+
+    (stats_string, counter)
+}
+
+/// check if the latest modification of the logfile is older than the modification date of the
+/// clippy binary, if this is true, we should clean the lintchec shared target directory and recheck
+fn lintcheck_needs_rerun(lintcheck_logs_path: &Path) -> bool {
+    if !lintcheck_logs_path.exists() {
+        return true;
+    }
+
+    let clippy_modified: std::time::SystemTime = {
+        let mut times = [CLIPPY_DRIVER_PATH, CARGO_CLIPPY_PATH].iter().map(|p| {
+            std::fs::metadata(p)
+                .expect("failed to get metadata of file")
+                .modified()
+                .expect("failed to get modification date")
+        });
+        // the oldest modification of either of the binaries
+        std::cmp::max(times.next().unwrap(), times.next().unwrap())
+    };
+
+    let logs_modified: std::time::SystemTime = std::fs::metadata(lintcheck_logs_path)
+        .expect("failed to get metadata of file")
+        .modified()
+        .expect("failed to get modification date");
+
+    // time is represented in seconds since X
+    // logs_modified 2 and clippy_modified 5 means clippy binary is older and we need to recheck
+    logs_modified < clippy_modified
+}
+
+fn main() {
+    // assert that we launch lintcheck from the repo root (via cargo lintcheck)
+    if std::fs::metadata("lintcheck/Cargo.toml").is_err() {
+        eprintln!("lintcheck needs to be run from clippy's repo root!\nUse `cargo lintcheck` alternatively.");
+        std::process::exit(3);
+    }
+
+    let config = LintcheckConfig::new();
+
+    println!("Compiling clippy...");
+    build_clippy();
+    println!("Done compiling");
+
+    // if the clippy bin is newer than our logs, throw away target dirs to force clippy to
+    // refresh the logs
+    if lintcheck_needs_rerun(&config.lintcheck_results_path) {
+        let shared_target_dir = "target/lintcheck/shared_target_dir";
+        // if we get an Err here, the shared target dir probably does simply not exist
+        if let Ok(metadata) = std::fs::metadata(&shared_target_dir) {
+            if metadata.is_dir() {
+                println!("Clippy is newer than lint check logs, clearing lintcheck shared target dir...");
+                std::fs::remove_dir_all(&shared_target_dir)
+                    .expect("failed to remove target/lintcheck/shared_target_dir");
+            }
+        }
+    }
+
+    let cargo_clippy_path: PathBuf = PathBuf::from(CARGO_CLIPPY_PATH)
+        .canonicalize()
+        .expect("failed to canonicalize path to clippy binary");
+
+    // assert that clippy is found
+    assert!(
+        cargo_clippy_path.is_file(),
+        "target/debug/cargo-clippy binary not found! {}",
+        cargo_clippy_path.display()
+    );
+
+    let clippy_ver = std::process::Command::new(CARGO_CLIPPY_PATH)
+        .arg("--version")
+        .output()
+        .map(|o| String::from_utf8_lossy(&o.stdout).into_owned())
+        .expect("could not get clippy version!");
+
+    // download and extract the crates, then run clippy on them and collect clippy's warnings
+    // flatten into one big list of warnings
+
+    let crates = read_crates(&config.sources_toml_path);
+    let old_stats = read_stats_from_file(&config.lintcheck_results_path);
+
+    let counter = AtomicUsize::new(1);
+    let lint_filter: Vec<String> = config
+        .lint_filter
+        .iter()
+        .map(|filter| {
+            let mut filter = filter.clone();
+            filter.insert_str(0, "--force-warn=");
+            filter
+        })
+        .collect();
+
+    let crates: Vec<Crate> = crates
+        .into_iter()
+        .filter(|krate| {
+            if let Some(only_one_crate) = &config.only {
+                let name = match krate {
+                    CrateSource::CratesIo { name, .. }
+                    | CrateSource::Git { name, .. }
+                    | CrateSource::Path { name, .. } => name,
+                };
+
+                name == only_one_crate
+            } else {
+                true
+            }
+        })
+        .map(|krate| krate.download_and_extract())
+        .collect();
+
+    if crates.is_empty() {
+        eprintln!(
+            "ERROR: could not find crate '{}' in lintcheck/lintcheck_crates.toml",
+            config.only.unwrap(),
+        );
+        std::process::exit(1);
+    }
+
+    // run parallel with rayon
+
+    // This helps when we check many small crates with dep-trees that don't have a lot of branches in
+    // order to achieve some kind of parallelism
+
+    rayon::ThreadPoolBuilder::new()
+        .num_threads(config.max_jobs)
+        .build_global()
+        .unwrap();
+
+    let clippy_warnings: Vec<ClippyWarning> = crates
+        .par_iter()
+        .flat_map(|krate| krate.run_clippy_lints(&cargo_clippy_path, &counter, crates.len(), &config, &lint_filter))
+        .collect();
+
+    // if we are in --fix mode, don't change the log files, terminate here
+    if config.fix {
+        return;
+    }
+
+    // generate some stats
+    let (stats_formatted, new_stats) = gather_stats(&clippy_warnings);
+
+    // grab crashes/ICEs, save the crate name and the ice message
+    let ices: Vec<(&String, &String)> = clippy_warnings
+        .iter()
+        .filter(|warning| warning.is_ice)
+        .map(|w| (&w.crate_name, &w.message))
+        .collect();
+
+    let mut all_msgs: Vec<String> = clippy_warnings
+        .iter()
+        .map(|warn| warn.to_output(config.markdown))
+        .collect();
+    all_msgs.sort();
+    all_msgs.push("\n\n### Stats:\n\n".into());
+    all_msgs.push(stats_formatted);
+
+    // save the text into lintcheck-logs/logs.txt
+    let mut text = clippy_ver; // clippy version number on top
+    text.push_str("\n### Reports\n\n");
+    if config.markdown {
+        text.push_str("| file | lint | message |\n");
+        text.push_str("| --- | --- | --- |\n");
+    }
+    write!(text, "{}", all_msgs.join("")).unwrap();
+    text.push_str("\n\n### ICEs:\n");
+    for (cratename, msg) in ices.iter() {
+        let _ = write!(text, "{}: '{}'", cratename, msg);
+    }
+
+    println!("Writing logs to {}", config.lintcheck_results_path.display());
+    std::fs::create_dir_all(config.lintcheck_results_path.parent().unwrap()).unwrap();
+    write(&config.lintcheck_results_path, text).unwrap();
+
+    print_stats(old_stats, new_stats, &config.lint_filter);
+}
+
+/// read the previous stats from the lintcheck-log file
+fn read_stats_from_file(file_path: &Path) -> HashMap<String, usize> {
+    let file_content: String = match std::fs::read_to_string(file_path).ok() {
+        Some(content) => content,
+        None => {
+            return HashMap::new();
+        },
+    };
+
+    let lines: Vec<String> = file_content.lines().map(ToString::to_string).collect();
+
+    lines
+        .iter()
+        .skip_while(|line| line.as_str() != "### Stats:")
+        // Skipping the table header and the `Stats:` label
+        .skip(4)
+        .take_while(|line| line.starts_with("| "))
+        .filter_map(|line| {
+            let mut spl = line.split('|');
+            // Skip the first `|` symbol
+            spl.next();
+            if let (Some(lint), Some(count)) = (spl.next(), spl.next()) {
+                Some((lint.trim().to_string(), count.trim().parse::<usize>().unwrap()))
+            } else {
+                None
+            }
+        })
+        .collect::<HashMap<String, usize>>()
+}
+
+/// print how lint counts changed between runs
+fn print_stats(old_stats: HashMap<String, usize>, new_stats: HashMap<&String, usize>, lint_filter: &Vec<String>) {
+    let same_in_both_hashmaps = old_stats
+        .iter()
+        .filter(|(old_key, old_val)| new_stats.get::<&String>(&old_key) == Some(old_val))
+        .map(|(k, v)| (k.to_string(), *v))
+        .collect::<Vec<(String, usize)>>();
+
+    let mut old_stats_deduped = old_stats;
+    let mut new_stats_deduped = new_stats;
+
+    // remove duplicates from both hashmaps
+    same_in_both_hashmaps.iter().for_each(|(k, v)| {
+        assert!(old_stats_deduped.remove(k) == Some(*v));
+        assert!(new_stats_deduped.remove(k) == Some(*v));
+    });
+
+    println!("\nStats:");
+
+    // list all new counts  (key is in new stats but not in old stats)
+    new_stats_deduped
+        .iter()
+        .filter(|(new_key, _)| old_stats_deduped.get::<str>(&new_key).is_none())
+        .for_each(|(new_key, new_value)| {
+            println!("{} 0 => {}", new_key, new_value);
+        });
+
+    // list all changed counts (key is in both maps but value differs)
+    new_stats_deduped
+        .iter()
+        .filter(|(new_key, _new_val)| old_stats_deduped.get::<str>(&new_key).is_some())
+        .for_each(|(new_key, new_val)| {
+            let old_val = old_stats_deduped.get::<str>(&new_key).unwrap();
+            println!("{} {} => {}", new_key, old_val, new_val);
+        });
+
+    // list all gone counts (key is in old status but not in new stats)
+    old_stats_deduped
+        .iter()
+        .filter(|(old_key, _)| new_stats_deduped.get::<&String>(&old_key).is_none())
+        .filter(|(old_key, _)| lint_filter.is_empty() || lint_filter.contains(old_key))
+        .for_each(|(old_key, old_value)| {
+            println!("{} {} => 0", old_key, old_value);
+        });
+}
+
+/// Create necessary directories to run the lintcheck tool.
+///
+/// # Panics
+///
+/// This function panics if creating one of the dirs fails.
+fn create_dirs(krate_download_dir: &Path, extract_dir: &Path) {
+    std::fs::create_dir("target/lintcheck/").unwrap_or_else(|err| {
+        if err.kind() != ErrorKind::AlreadyExists {
+            panic!("cannot create lintcheck target dir");
+        }
+    });
+    std::fs::create_dir(&krate_download_dir).unwrap_or_else(|err| {
+        if err.kind() != ErrorKind::AlreadyExists {
+            panic!("cannot create crate download dir");
+        }
+    });
+    std::fs::create_dir(&extract_dir).unwrap_or_else(|err| {
+        if err.kind() != ErrorKind::AlreadyExists {
+            panic!("cannot create crate extraction dir");
+        }
+    });
+}
+
+/// Returns the path to the Clippy project directory
+#[must_use]
+fn clippy_project_root() -> &'static Path {
+    Path::new(env!("CARGO_MANIFEST_DIR")).parent().unwrap()
+}
+
+#[test]
+fn lintcheck_test() {
+    let args = [
+        "run",
+        "--target-dir",
+        "lintcheck/target",
+        "--manifest-path",
+        "./lintcheck/Cargo.toml",
+        "--",
+        "--crates-toml",
+        "lintcheck/test_sources.toml",
+    ];
+    let status = std::process::Command::new("cargo")
+        .args(&args)
+        .current_dir("..") // repo root
+        .status();
+    //.output();
+
+    assert!(status.unwrap().success());
+}
diff --git a/src/tools/clippy/lintcheck/test_sources.toml b/src/tools/clippy/lintcheck/test_sources.toml
new file mode 100644
index 000000000..4b0eb71ef
--- /dev/null
+++ b/src/tools/clippy/lintcheck/test_sources.toml
@@ -0,0 +1,4 @@
+[crates]
+cc = {name = "cc", versions = ['1.0.67']}
+home = {name = "home", git_url = "https://github.com/brson/home", git_hash = "32044e53dfbdcd32bafad3109d1fbab805fc0f40"}
+rustc_tools_util = {name = "rustc_tools_util", versions = ['0.2.0']}