compiletest: consistently use `{Utf8Path,Utf8PathBuf}`

Since compiletest already assumes UTF-8 paths and does not try to be
robust against non-UTF-8 paths.

20 files changed, 403 insertions, 433 deletions

diff --git a/src/tools/compiletest/src/common.rs b/src/tools/compiletest/src/common.rs
index 6750b5288f4..604c5fcbddf 100644
--- a/src/tools/compiletest/src/common.rs
+++ b/src/tools/compiletest/src/common.rs
@@ -1,18 +1,17 @@
 use std::collections::{BTreeSet, HashMap, HashSet};
-use std::ffi::OsString;
-use std::path::{Path, PathBuf};
 use std::process::Command;
 use std::str::FromStr;
 use std::sync::OnceLock;
 use std::{fmt, iter};
 
 use build_helper::git::GitConfig;
+use camino::{Utf8Path, Utf8PathBuf};
 use semver::Version;
 use serde::de::{Deserialize, Deserializer, Error as _};
 
 pub use self::Mode::*;
 use crate::executor::{ColorConfig, OutputFormat};
-use crate::util::{PathBufExt, add_dylib_path};
+use crate::util::{Utf8PathBufExt, add_dylib_path};
 
 macro_rules! string_enum {
     ($(#[$meta:meta])* $vis:vis enum $name:ident { $($variant:ident => $repr:expr,)* }) => {
@@ -183,25 +182,25 @@ pub struct Config {
     pub fail_fast: bool,
 
     /// The library paths required for running the compiler.
-    pub compile_lib_path: PathBuf,
+    pub compile_lib_path: Utf8PathBuf,
 
     /// The library paths required for running compiled programs.
-    pub run_lib_path: PathBuf,
+    pub run_lib_path: Utf8PathBuf,
 
     /// The rustc executable.
-    pub rustc_path: PathBuf,
+    pub rustc_path: Utf8PathBuf,
 
     /// The cargo executable.
-    pub cargo_path: Option<PathBuf>,
+    pub cargo_path: Option<Utf8PathBuf>,
 
     /// Rustc executable used to compile run-make recipes.
-    pub stage0_rustc_path: Option<PathBuf>,
+    pub stage0_rustc_path: Option<Utf8PathBuf>,
 
     /// The rustdoc executable.
-    pub rustdoc_path: Option<PathBuf>,
+    pub rustdoc_path: Option<Utf8PathBuf>,
 
     /// The coverage-dump executable.
-    pub coverage_dump_path: Option<PathBuf>,
+    pub coverage_dump_path: Option<Utf8PathBuf>,
 
     /// The Python executable to use for LLDB and htmldocck.
     pub python: String,
@@ -213,27 +212,27 @@ pub struct Config {
     pub jsondoclint_path: Option<String>,
 
     /// The LLVM `FileCheck` binary path.
-    pub llvm_filecheck: Option<PathBuf>,
+    pub llvm_filecheck: Option<Utf8PathBuf>,
 
     /// Path to LLVM's bin directory.
-    pub llvm_bin_dir: Option<PathBuf>,
+    pub llvm_bin_dir: Option<Utf8PathBuf>,
 
     /// The path to the Clang executable to run Clang-based tests with. If
     /// `None` then these tests will be ignored.
     pub run_clang_based_tests_with: Option<String>,
 
     /// The directory containing the sources.
-    pub src_root: PathBuf,
+    pub src_root: Utf8PathBuf,
     /// The directory containing the test suite sources. Must be a subdirectory of `src_root`.
-    pub src_test_suite_root: PathBuf,
+    pub src_test_suite_root: Utf8PathBuf,
 
     /// Root build directory (e.g. `build/`).
-    pub build_root: PathBuf,
+    pub build_root: Utf8PathBuf,
     /// Test suite specific build directory (e.g. `build/host/test/ui/`).
-    pub build_test_suite_root: PathBuf,
+    pub build_test_suite_root: Utf8PathBuf,
 
     /// The directory containing the compiler sysroot
-    pub sysroot_base: PathBuf,
+    pub sysroot_base: Utf8PathBuf,
 
     /// The number of the stage under test.
     pub stage: u32,
@@ -301,7 +300,7 @@ pub struct Config {
     pub host: String,
 
     /// Path to / name of the Microsoft Console Debugger (CDB) executable
-    pub cdb: Option<OsString>,
+    pub cdb: Option<Utf8PathBuf>,
 
     /// Version of CDB
     pub cdb_version: Option<[u16; 4]>,
@@ -322,7 +321,7 @@ pub struct Config {
     pub system_llvm: bool,
 
     /// Path to the android tools
-    pub android_cross_path: PathBuf,
+    pub android_cross_path: Utf8PathBuf,
 
     /// Extra parameter to run adb on arm-linux-androideabi
     pub adb_path: String,
@@ -346,7 +345,7 @@ pub struct Config {
     pub color: ColorConfig,
 
     /// where to find the remote test client process, if we're using it
-    pub remote_test_client: Option<PathBuf>,
+    pub remote_test_client: Option<Utf8PathBuf>,
 
     /// mode describing what file the actual ui output will be compared to
     pub compare_mode: Option<CompareMode>,
@@ -414,7 +413,7 @@ pub struct Config {
     /// Path to minicore aux library, used for `no_core` tests that need `core` stubs in
     /// cross-compilation scenarios that do not otherwise want/need to `-Zbuild-std`. Used in e.g.
     /// ABI tests.
-    pub minicore_path: PathBuf,
+    pub minicore_path: Utf8PathBuf,
 }
 
 impl Config {
@@ -804,8 +803,8 @@ fn serde_parse_u32<'de, D: Deserializer<'de>>(deserializer: D) -> Result<u32, D:
 
 #[derive(Debug, Clone)]
 pub struct TestPaths {
-    pub file: PathBuf,         // e.g., compile-test/foo/bar/baz.rs
-    pub relative_dir: PathBuf, // e.g., foo/bar
+    pub file: Utf8PathBuf,         // e.g., compile-test/foo/bar/baz.rs
+    pub relative_dir: Utf8PathBuf, // e.g., foo/bar
 }
 
 /// Used by `ui` tests to generate things like `foo.stderr` from `foo.rs`.
@@ -814,7 +813,7 @@ pub fn expected_output_path(
     revision: Option<&str>,
     compare_mode: &Option<CompareMode>,
     kind: &str,
-) -> PathBuf {
+) -> Utf8PathBuf {
     assert!(UI_EXTENSIONS.contains(&kind));
     let mut parts = Vec::new();
 
@@ -865,7 +864,7 @@ pub const UI_COVERAGE_MAP: &str = "cov-map";
 /// ```
 ///
 /// This is created early when tests are collected to avoid race conditions.
-pub fn output_relative_path(config: &Config, relative_dir: &Path) -> PathBuf {
+pub fn output_relative_path(config: &Config, relative_dir: &Utf8Path) -> Utf8PathBuf {
     config.build_test_suite_root.join(relative_dir)
 }
 
@@ -874,10 +873,10 @@ pub fn output_testname_unique(
     config: &Config,
     testpaths: &TestPaths,
     revision: Option<&str>,
-) -> PathBuf {
+) -> Utf8PathBuf {
     let mode = config.compare_mode.as_ref().map_or("", |m| m.to_str());
     let debugger = config.debugger.as_ref().map_or("", |m| m.to_str());
-    PathBuf::from(&testpaths.file.file_stem().unwrap())
+    Utf8PathBuf::from(&testpaths.file.file_stem().unwrap())
         .with_extra_extension(config.mode.output_dir_disambiguator())
         .with_extra_extension(revision.unwrap_or(""))
         .with_extra_extension(mode)
@@ -887,7 +886,11 @@ pub fn output_testname_unique(
 /// Absolute path to the directory where all output for the given
 /// test/revision should reside. Example:
 ///   /path/to/build/host-tuple/test/ui/relative/testname.revision.mode/
-pub fn output_base_dir(config: &Config, testpaths: &TestPaths, revision: Option<&str>) -> PathBuf {
+pub fn output_base_dir(
+    config: &Config,
+    testpaths: &TestPaths,
+    revision: Option<&str>,
+) -> Utf8PathBuf {
     output_relative_path(config, &testpaths.relative_dir)
         .join(output_testname_unique(config, testpaths, revision))
 }
@@ -895,12 +898,20 @@ pub fn output_base_dir(config: &Config, testpaths: &TestPaths, revision: Option<
 /// Absolute path to the base filename used as output for the given
 /// test/revision. Example:
 ///   /path/to/build/host-tuple/test/ui/relative/testname.revision.mode/testname
-pub fn output_base_name(config: &Config, testpaths: &TestPaths, revision: Option<&str>) -> PathBuf {
+pub fn output_base_name(
+    config: &Config,
+    testpaths: &TestPaths,
+    revision: Option<&str>,
+) -> Utf8PathBuf {
     output_base_dir(config, testpaths, revision).join(testpaths.file.file_stem().unwrap())
 }
 
 /// Absolute path to the directory to use for incremental compilation. Example:
 ///   /path/to/build/host-tuple/test/ui/relative/testname.mode/testname.inc
-pub fn incremental_dir(config: &Config, testpaths: &TestPaths, revision: Option<&str>) -> PathBuf {
+pub fn incremental_dir(
+    config: &Config,
+    testpaths: &TestPaths,
+    revision: Option<&str>,
+) -> Utf8PathBuf {
     output_base_name(config, testpaths, revision).with_extension("inc")
 }
diff --git a/src/tools/compiletest/src/compute_diff.rs b/src/tools/compiletest/src/compute_diff.rs
index 4c942c51bae..509e7e11703 100644
--- a/src/tools/compiletest/src/compute_diff.rs
+++ b/src/tools/compiletest/src/compute_diff.rs
@@ -1,6 +1,7 @@
 use std::collections::VecDeque;
 use std::fs::{File, FileType};
-use std::path::Path;
+
+use camino::Utf8Path;
 
 #[derive(Debug, PartialEq)]
 pub enum DiffLine {
@@ -112,8 +113,8 @@ pub(crate) fn write_diff(expected: &str, actual: &str, context_size: usize) -> S
 /// Returns whether any data was actually written.
 pub(crate) fn write_filtered_diff<Filter>(
     diff_filename: &str,
-    out_dir: &Path,
-    compare_dir: &Path,
+    out_dir: &Utf8Path,
+    compare_dir: &Utf8Path,
     verbose: bool,
     filter: Filter,
 ) -> bool
@@ -123,19 +124,21 @@ where
     use std::io::{Read, Write};
     let mut diff_output = File::create(diff_filename).unwrap();
     let mut wrote_data = false;
-    for entry in walkdir::WalkDir::new(out_dir) {
+    for entry in walkdir::WalkDir::new(out_dir.as_std_path()) {
         let entry = entry.expect("failed to read file");
         let extension = entry.path().extension().and_then(|p| p.to_str());
         if filter(entry.file_type(), extension) {
-            let expected_path = compare_dir.join(entry.path().strip_prefix(&out_dir).unwrap());
+            let expected_path = compare_dir
+                .as_std_path()
+                .join(entry.path().strip_prefix(&out_dir.as_std_path()).unwrap());
             let expected = if let Ok(s) = std::fs::read(&expected_path) { s } else { continue };
             let actual_path = entry.path();
             let actual = std::fs::read(&actual_path).unwrap();
             let diff = unified_diff::diff(
                 &expected,
-                &expected_path.to_string_lossy(),
+                &expected_path.to_str().unwrap(),
                 &actual,
-                &actual_path.to_string_lossy(),
+                &actual_path.to_str().unwrap(),
                 3,
             );
             wrote_data |= !diff.is_empty();
diff --git a/src/tools/compiletest/src/debuggers.rs b/src/tools/compiletest/src/debuggers.rs
index 5126e55aea1..c133d7fd4fb 100644
--- a/src/tools/compiletest/src/debuggers.rs
+++ b/src/tools/compiletest/src/debuggers.rs
@@ -1,9 +1,9 @@
 use std::env;
-use std::ffi::OsString;
-use std::path::{Path, PathBuf};
 use std::process::Command;
 use std::sync::Arc;
 
+use camino::{Utf8Path, Utf8PathBuf};
+
 use crate::common::{Config, Debugger};
 
 pub(crate) fn configure_cdb(config: &Config) -> Option<Arc<Config>> {
@@ -78,12 +78,15 @@ fn is_pc_windows_msvc_target(target: &str) -> bool {
     target.ends_with("-pc-windows-msvc")
 }
 
-fn find_cdb(target: &str) -> Option<OsString> {
+fn find_cdb(target: &str) -> Option<Utf8PathBuf> {
     if !(cfg!(windows) && is_pc_windows_msvc_target(target)) {
         return None;
     }
 
-    let pf86 = env::var_os("ProgramFiles(x86)").or_else(|| env::var_os("ProgramFiles"))?;
+    let pf86 = Utf8PathBuf::from_path_buf(
+        env::var_os("ProgramFiles(x86)").or_else(|| env::var_os("ProgramFiles"))?.into(),
+    )
+    .unwrap();
     let cdb_arch = if cfg!(target_arch = "x86") {
         "x86"
     } else if cfg!(target_arch = "x86_64") {
@@ -96,8 +99,7 @@ fn find_cdb(target: &str) -> Option<OsString> {
         return None; // No compatible CDB.exe in the Windows 10 SDK
     };
 
-    let mut path = PathBuf::new();
-    path.push(pf86);
+    let mut path = pf86;
     path.push(r"Windows Kits\10\Debuggers"); // We could check 8.1 etc. too?
     path.push(cdb_arch);
     path.push(r"cdb.exe");
@@ -106,15 +108,15 @@ fn find_cdb(target: &str) -> Option<OsString> {
         return None;
     }
 
-    Some(path.into_os_string())
+    Some(path)
 }
 
 /// Returns Path to CDB
 pub(crate) fn analyze_cdb(
     cdb: Option<String>,
     target: &str,
-) -> (Option<OsString>, Option<[u16; 4]>) {
-    let cdb = cdb.map(OsString::from).or_else(|| find_cdb(target));
+) -> (Option<Utf8PathBuf>, Option<[u16; 4]>) {
+    let cdb = cdb.map(Utf8PathBuf::from).or_else(|| find_cdb(target));
 
     let mut version = None;
     if let Some(cdb) = cdb.as_ref() {
@@ -143,7 +145,7 @@ pub(crate) fn extract_cdb_version(full_version_line: &str) -> Option<[u16; 4]> {
 pub(crate) fn analyze_gdb(
     gdb: Option<String>,
     target: &str,
-    android_cross_path: &Path,
+    android_cross_path: &Utf8Path,
 ) -> (Option<String>, Option<u32>) {
     #[cfg(not(windows))]
     const GDB_FALLBACK: &str = "gdb";
@@ -152,10 +154,7 @@ pub(crate) fn analyze_gdb(
 
     let fallback_gdb = || {
         if is_android_gdb_target(target) {
-            let mut gdb_path = match android_cross_path.to_str() {
-                Some(x) => x.to_owned(),
-                None => panic!("cannot find android cross path"),
-            };
+            let mut gdb_path = android_cross_path.to_string();
             gdb_path.push_str("/bin/gdb");
             gdb_path
         } else {
diff --git a/src/tools/compiletest/src/errors.rs b/src/tools/compiletest/src/errors.rs
index 64d68eb7f23..3bb98276bf5 100644
--- a/src/tools/compiletest/src/errors.rs
+++ b/src/tools/compiletest/src/errors.rs
@@ -2,9 +2,9 @@ use std::fmt;
 use std::fs::File;
 use std::io::BufReader;
 use std::io::prelude::*;
-use std::path::Path;
 use std::sync::OnceLock;
 
+use camino::Utf8Path;
 use regex::Regex;
 use tracing::*;
 
@@ -102,8 +102,8 @@ impl Error {
 ///
 /// If revision is not None, then we look
 /// for `//[X]~` instead, where `X` is the current revision.
-pub fn load_errors(testfile: &Path, revision: Option<&str>) -> Vec<Error> {
-    let rdr = BufReader::new(File::open(testfile).unwrap());
+pub fn load_errors(testfile: &Utf8Path, revision: Option<&str>) -> Vec<Error> {
+    let rdr = BufReader::new(File::open(testfile.as_std_path()).unwrap());
 
     // `last_nonfollow_error` tracks the most recently seen
     // line with an error template that did not use the
diff --git a/src/tools/compiletest/src/header.rs b/src/tools/compiletest/src/header.rs
index 3406e8749a1..33ecdec4991 100644
--- a/src/tools/compiletest/src/header.rs
+++ b/src/tools/compiletest/src/header.rs
@@ -3,9 +3,9 @@ use std::env;
 use std::fs::File;
 use std::io::BufReader;
 use std::io::prelude::*;
-use std::path::{Path, PathBuf};
 use std::process::Command;
 
+use camino::{Utf8Path, Utf8PathBuf};
 use semver::Version;
 use tracing::*;
 
@@ -45,12 +45,12 @@ pub struct EarlyProps {
 }
 
 impl EarlyProps {
-    pub fn from_file(config: &Config, testfile: &Path) -> Self {
-        let file = File::open(testfile).expect("open test file to parse earlyprops");
+    pub fn from_file(config: &Config, testfile: &Utf8Path) -> Self {
+        let file = File::open(testfile.as_std_path()).expect("open test file to parse earlyprops");
         Self::from_reader(config, testfile, file)
     }
 
-    pub fn from_reader<R: Read>(config: &Config, testfile: &Path, rdr: R) -> Self {
+    pub fn from_reader<R: Read>(config: &Config, testfile: &Utf8Path, rdr: R) -> Self {
         let mut props = EarlyProps::default();
         let mut poisoned = false;
         iter_header(
@@ -66,7 +66,7 @@ impl EarlyProps {
         );
 
         if poisoned {
-            eprintln!("errors encountered during EarlyProps parsing: {}", testfile.display());
+            eprintln!("errors encountered during EarlyProps parsing: {}", testfile);
             panic!("errors encountered during EarlyProps parsing");
         }
 
@@ -88,7 +88,7 @@ pub struct TestProps {
     pub doc_flags: Vec<String>,
     // If present, the name of a file that this test should match when
     // pretty-printed
-    pub pp_exact: Option<PathBuf>,
+    pub pp_exact: Option<Utf8PathBuf>,
     /// Auxiliary crates that should be built and made available to this test.
     pub(crate) aux: AuxProps,
     // Environment settings to use for compiling
@@ -134,7 +134,7 @@ pub struct TestProps {
     // not set by end-users; rather it is set by the incremental
     // testing harness and used when generating compilation
     // arguments. (In particular, it propagates to the aux-builds.)
-    pub incremental_dir: Option<PathBuf>,
+    pub incremental_dir: Option<Utf8PathBuf>,
     // If `true`, this test will use incremental compilation.
     //
     // This can be set manually with the `incremental` header, or implicitly
@@ -311,7 +311,12 @@ impl TestProps {
         }
     }
 
-    pub fn from_aux_file(&self, testfile: &Path, revision: Option<&str>, config: &Config) -> Self {
+    pub fn from_aux_file(
+        &self,
+        testfile: &Utf8Path,
+        revision: Option<&str>,
+        config: &Config,
+    ) -> Self {
         let mut props = TestProps::new();
 
         // copy over select properties to the aux build:
@@ -322,10 +327,10 @@ impl TestProps {
         props
     }
 
-    pub fn from_file(testfile: &Path, revision: Option<&str>, config: &Config) -> Self {
+    pub fn from_file(testfile: &Utf8Path, revision: Option<&str>, config: &Config) -> Self {
         let mut props = TestProps::new();
         props.load_from(testfile, revision, config);
-        props.exec_env.push(("RUSTC".to_string(), config.rustc_path.display().to_string()));
+        props.exec_env.push(("RUSTC".to_string(), config.rustc_path.to_string()));
 
         match (props.pass_mode, props.fail_mode) {
             (None, None) if config.mode == Mode::Ui => props.fail_mode = Some(FailMode::Check),
@@ -340,10 +345,10 @@ impl TestProps {
     /// tied to a particular revision `foo` (indicated by writing
     /// `//@[foo]`), then the property is ignored unless `test_revision` is
     /// `Some("foo")`.
-    fn load_from(&mut self, testfile: &Path, test_revision: Option<&str>, config: &Config) {
+    fn load_from(&mut self, testfile: &Utf8Path, test_revision: Option<&str>, config: &Config) {
         let mut has_edition = false;
         if !testfile.is_dir() {
-            let file = File::open(testfile).unwrap();
+            let file = File::open(testfile.as_std_path()).unwrap();
 
             let mut poisoned = false;
 
@@ -600,7 +605,7 @@ impl TestProps {
             );
 
             if poisoned {
-                eprintln!("errors encountered during TestProps parsing: {}", testfile.display());
+                eprintln!("errors encountered during TestProps parsing: {}", testfile);
                 panic!("errors encountered during TestProps parsing");
             }
         }
@@ -871,7 +876,7 @@ fn iter_header(
     mode: Mode,
     _suite: &str,
     poisoned: &mut bool,
-    testfile: &Path,
+    testfile: &Utf8Path,
     rdr: impl Read,
     it: &mut dyn FnMut(DirectiveLine<'_>),
 ) {
@@ -923,9 +928,7 @@ fn iter_header(
 
                 eprintln!(
                     "error: detected unknown compiletest test directive `{}` in {}:{}",
-                    directive_line.raw_directive,
-                    testfile.display(),
-                    line_number,
+                    directive_line.raw_directive, testfile, line_number,
                 );
 
                 return;
@@ -937,10 +940,7 @@ fn iter_header(
                 eprintln!(
                     "error: detected trailing compiletest test directive `{}` in {}:{}\n \
                       help: put the trailing directive in it's own line: `//@ {}`",
-                    trailing_directive,
-                    testfile.display(),
-                    line_number,
-                    trailing_directive,
+                    trailing_directive, testfile, line_number, trailing_directive,
                 );
 
                 return;
@@ -952,7 +952,12 @@ fn iter_header(
 }
 
 impl Config {
-    fn parse_and_update_revisions(&self, testfile: &Path, line: &str, existing: &mut Vec<String>) {
+    fn parse_and_update_revisions(
+        &self,
+        testfile: &Utf8Path,
+        line: &str,
+        existing: &mut Vec<String>,
+    ) {
         const FORBIDDEN_REVISION_NAMES: [&str; 2] = [
             // `//@ revisions: true false` Implying `--cfg=true` and `--cfg=false` makes it very
             // weird for the test, since if the test writer wants a cfg of the same revision name
@@ -965,26 +970,19 @@ impl Config {
 
         if let Some(raw) = self.parse_name_value_directive(line, "revisions") {
             if self.mode == Mode::RunMake {
-                panic!("`run-make` tests do not support revisions: {}", testfile.display());
+                panic!("`run-make` tests do not support revisions: {}", testfile);
             }
 
             let mut duplicates: HashSet<_> = existing.iter().cloned().collect();
             for revision in raw.split_whitespace() {
                 if !duplicates.insert(revision.to_string()) {
-                    panic!(
-                        "duplicate revision: `{}` in line `{}`: {}",
-                        revision,
-                        raw,
-                        testfile.display()
-                    );
+                    panic!("duplicate revision: `{}` in line `{}`: {}", revision, raw, testfile);
                 }
 
                 if FORBIDDEN_REVISION_NAMES.contains(&revision) {
                     panic!(
                         "revision name `{revision}` is not permitted: `{}` in line `{}`: {}",
-                        revision,
-                        raw,
-                        testfile.display()
+                        revision, raw, testfile
                     );
                 }
 
@@ -995,8 +993,7 @@ impl Config {
                         "revision name `{revision}` is not permitted in a test suite that uses \
                         `FileCheck` annotations as it is confusing when used as custom `FileCheck` \
                         prefix: `{revision}` in line `{}`: {}",
-                        raw,
-                        testfile.display()
+                        raw, testfile
                     );
                 }
 
@@ -1016,11 +1013,11 @@ impl Config {
         (name.to_owned(), value.to_owned())
     }
 
-    fn parse_pp_exact(&self, line: &str, testfile: &Path) -> Option<PathBuf> {
+    fn parse_pp_exact(&self, line: &str, testfile: &Utf8Path) -> Option<Utf8PathBuf> {
         if let Some(s) = self.parse_name_value_directive(line, "pp-exact") {
-            Some(PathBuf::from(&s))
+            Some(Utf8PathBuf::from(&s))
         } else if self.parse_name_directive(line, "pp-exact") {
-            testfile.file_name().map(PathBuf::from)
+            testfile.file_name().map(Utf8PathBuf::from)
         } else {
             None
         }
@@ -1126,20 +1123,19 @@ fn expand_variables(mut value: String, config: &Config) -> String {
 
     if value.contains(CWD) {
         let cwd = env::current_dir().unwrap();
-        value = value.replace(CWD, &cwd.to_string_lossy());
+        value = value.replace(CWD, &cwd.to_str().unwrap());
     }
 
     if value.contains(SRC_BASE) {
-        value = value.replace(SRC_BASE, &config.src_test_suite_root.to_str().unwrap());
+        value = value.replace(SRC_BASE, &config.src_test_suite_root.as_str());
     }
 
     if value.contains(TEST_SUITE_BUILD_BASE) {
-        value =
-            value.replace(TEST_SUITE_BUILD_BASE, &config.build_test_suite_root.to_str().unwrap());
+        value = value.replace(TEST_SUITE_BUILD_BASE, &config.build_test_suite_root.as_str());
     }
 
     if value.contains(SYSROOT_BASE) {
-        value = value.replace(SYSROOT_BASE, &config.sysroot_base.to_str().unwrap());
+        value = value.replace(SYSROOT_BASE, &config.sysroot_base.as_str());
     }
 
     if value.contains(TARGET_LINKER) {
@@ -1152,9 +1148,9 @@ fn expand_variables(mut value: String, config: &Config) -> String {
 
     if value.contains(RUST_SRC_BASE) {
         let src_base = config.sysroot_base.join("lib/rustlib/src/rust");
-        src_base.try_exists().expect(&*format!("{} should exists", src_base.display()));
-        let src_base = src_base.read_link().unwrap_or(src_base);
-        value = value.replace(RUST_SRC_BASE, &src_base.to_string_lossy());
+        src_base.try_exists().expect(&*format!("{} should exists", src_base));
+        let src_base = src_base.read_link_utf8().unwrap_or(src_base);
+        value = value.replace(RUST_SRC_BASE, &src_base.as_str());
     }
 
     value
@@ -1257,14 +1253,14 @@ pub fn llvm_has_libzstd(config: &Config) -> bool {
     // contains a path to that static lib, and that it exists.
     //
     // See compiler/rustc_llvm/build.rs for more details and similar expectations.
-    fn is_zstd_in_config(llvm_bin_dir: &Path) -> Option<()> {
+    fn is_zstd_in_config(llvm_bin_dir: &Utf8Path) -> Option<()> {
         let llvm_config_path = llvm_bin_dir.join("llvm-config");
         let output = Command::new(llvm_config_path).arg("--system-libs").output().ok()?;
         assert!(output.status.success(), "running llvm-config --system-libs failed");
 
         let libs = String::from_utf8(output.stdout).ok()?;
         for lib in libs.split_whitespace() {
-            if lib.ends_with("libzstd.a") && Path::new(lib).exists() {
+            if lib.ends_with("libzstd.a") && Utf8Path::new(lib).exists() {
                 return Some(());
             }
         }
@@ -1282,7 +1278,7 @@ pub fn llvm_has_libzstd(config: &Config) -> bool {
     // `lld` supports it. If not, an error will be emitted: "LLVM was not built with
     // LLVM_ENABLE_ZSTD or did not find zstd at build time".
     #[cfg(unix)]
-    fn is_lld_built_with_zstd(llvm_bin_dir: &Path) -> Option<()> {
+    fn is_lld_built_with_zstd(llvm_bin_dir: &Utf8Path) -> Option<()> {
         let lld_path = llvm_bin_dir.join("lld");
         if lld_path.exists() {
             // We can't call `lld` as-is, it expects to be invoked by a compiler driver using a
@@ -1318,7 +1314,7 @@ pub fn llvm_has_libzstd(config: &Config) -> bool {
     }
 
     #[cfg(not(unix))]
-    fn is_lld_built_with_zstd(_llvm_bin_dir: &Path) -> Option<()> {
+    fn is_lld_built_with_zstd(_llvm_bin_dir: &Utf8Path) -> Option<()> {
         None
     }
 
@@ -1385,7 +1381,7 @@ pub(crate) fn make_test_description<R: Read>(
     config: &Config,
     cache: &HeadersCache,
     name: String,
-    path: &Path,
+    path: &Utf8Path,
     src: R,
     test_revision: Option<&str>,
     poisoned: &mut bool,
@@ -1416,7 +1412,7 @@ pub(crate) fn make_test_description<R: Read>(
                             ignore_message = Some(reason.into());
                         }
                         IgnoreDecision::Error { message } => {
-                            eprintln!("error: {}:{line_number}: {message}", path.display());
+                            eprintln!("error: {}:{line_number}: {message}", path);
                             *poisoned = true;
                             return;
                         }
@@ -1446,7 +1442,7 @@ pub(crate) fn make_test_description<R: Read>(
     );
 
     if local_poisoned {
-        eprintln!("errors encountered when trying to make test description: {}", path.display());
+        eprintln!("errors encountered when trying to make test description: {}", path);
         panic!("errors encountered when trying to make test description");
     }
 
@@ -1555,7 +1551,7 @@ fn ignore_lldb(config: &Config, line: &str) -> IgnoreDecision {
     IgnoreDecision::Continue
 }
 
-fn ignore_llvm(config: &Config, path: &Path, line: &str) -> IgnoreDecision {
+fn ignore_llvm(config: &Config, path: &Utf8Path, line: &str) -> IgnoreDecision {
     if let Some(needed_components) =
         config.parse_name_value_directive(line, "needs-llvm-components")
     {
@@ -1567,8 +1563,7 @@ fn ignore_llvm(config: &Config, path: &Path, line: &str) -> IgnoreDecision {
             if env::var_os("COMPILETEST_REQUIRE_ALL_LLVM_COMPONENTS").is_some() {
                 panic!(
                     "missing LLVM component {}, and COMPILETEST_REQUIRE_ALL_LLVM_COMPONENTS is set: {}",
-                    missing_component,
-                    path.display()
+                    missing_component, path
                 );
             }
             return IgnoreDecision::Ignore {
diff --git a/src/tools/compiletest/src/header/tests.rs b/src/tools/compiletest/src/header/tests.rs
index f3461f3c244..3a8c3748de9 100644
--- a/src/tools/compiletest/src/header/tests.rs
+++ b/src/tools/compiletest/src/header/tests.rs
@@ -1,6 +1,6 @@
 use std::io::Read;
-use std::path::Path;
 
+use camino::Utf8Path;
 use semver::Version;
 
 use super::{
@@ -13,7 +13,7 @@ use crate::executor::{CollectedTestDesc, ShouldPanic};
 fn make_test_description<R: Read>(
     config: &Config,
     name: String,
-    path: &Path,
+    path: &Utf8Path,
     src: R,
     revision: Option<&str>,
 ) -> CollectedTestDesc {
@@ -230,12 +230,12 @@ fn cfg() -> ConfigBuilder {
 
 fn parse_rs(config: &Config, contents: &str) -> EarlyProps {
     let bytes = contents.as_bytes();
-    EarlyProps::from_reader(config, Path::new("a.rs"), bytes)
+    EarlyProps::from_reader(config, Utf8Path::new("a.rs"), bytes)
 }
 
 fn check_ignore(config: &Config, contents: &str) -> bool {
     let tn = String::new();
-    let p = Path::new("a.rs");
+    let p = Utf8Path::new("a.rs");
     let d = make_test_description(&config, tn, p, std::io::Cursor::new(contents), None);
     d.ignore
 }
@@ -244,7 +244,7 @@ fn check_ignore(config: &Config, contents: &str) -> bool {
 fn should_fail() {
     let config: Config = cfg().build();
     let tn = String::new();
-    let p = Path::new("a.rs");
+    let p = Utf8Path::new("a.rs");
 
     let d = make_test_description(&config, tn.clone(), p, std::io::Cursor::new(""), None);
     assert_eq!(d.should_panic, ShouldPanic::No);
@@ -784,7 +784,7 @@ fn threads_support() {
     }
 }
 
-fn run_path(poisoned: &mut bool, path: &Path, buf: &[u8]) {
+fn run_path(poisoned: &mut bool, path: &Utf8Path, buf: &[u8]) {
     let rdr = std::io::Cursor::new(&buf);
     iter_header(Mode::Ui, "ui", poisoned, path, rdr, &mut |_| {});
 }
@@ -794,7 +794,7 @@ fn test_unknown_directive_check() {
     let mut poisoned = false;
     run_path(
         &mut poisoned,
-        Path::new("a.rs"),
+        Utf8Path::new("a.rs"),
         include_bytes!("./test-auxillary/unknown_directive.rs"),
     );
     assert!(poisoned);
@@ -805,7 +805,7 @@ fn test_known_directive_check_no_error() {
     let mut poisoned = false;
     run_path(
         &mut poisoned,
-        Path::new("a.rs"),
+        Utf8Path::new("a.rs"),
         include_bytes!("./test-auxillary/known_directive.rs"),
     );
     assert!(!poisoned);
@@ -816,7 +816,7 @@ fn test_error_annotation_no_error() {
     let mut poisoned = false;
     run_path(
         &mut poisoned,
-        Path::new("a.rs"),
+        Utf8Path::new("a.rs"),
         include_bytes!("./test-auxillary/error_annotation.rs"),
     );
     assert!(!poisoned);
@@ -827,7 +827,7 @@ fn test_non_rs_unknown_directive_not_checked() {
     let mut poisoned = false;
     run_path(
         &mut poisoned,
-        Path::new("a.Makefile"),
+        Utf8Path::new("a.Makefile"),
         include_bytes!("./test-auxillary/not_rs.Makefile"),
     );
     assert!(!poisoned);
@@ -836,21 +836,21 @@ fn test_non_rs_unknown_directive_not_checked() {
 #[test]
 fn test_trailing_directive() {
     let mut poisoned = false;
-    run_path(&mut poisoned, Path::new("a.rs"), b"//@ only-x86 only-arm");
+    run_path(&mut poisoned, Utf8Path::new("a.rs"), b"//@ only-x86 only-arm");
     assert!(poisoned);
 }
 
 #[test]
 fn test_trailing_directive_with_comment() {
     let mut poisoned = false;
-    run_path(&mut poisoned, Path::new("a.rs"), b"//@ only-x86   only-arm with comment");
+    run_path(&mut poisoned, Utf8Path::new("a.rs"), b"//@ only-x86   only-arm with comment");
     assert!(poisoned);
 }
 
 #[test]
 fn test_not_trailing_directive() {
     let mut poisoned = false;
-    run_path(&mut poisoned, Path::new("a.rs"), b"//@ revisions: incremental");
+    run_path(&mut poisoned, Utf8Path::new("a.rs"), b"//@ revisions: incremental");
     assert!(!poisoned);
 }
 
diff --git a/src/tools/compiletest/src/lib.rs b/src/tools/compiletest/src/lib.rs
index 720663b30ef..b969b22750b 100644
--- a/src/tools/compiletest/src/lib.rs
+++ b/src/tools/compiletest/src/lib.rs
@@ -22,16 +22,15 @@ pub mod util;
 
 use core::panic;
 use std::collections::HashSet;
-use std::ffi::OsString;
 use std::fmt::Write;
 use std::io::{self, ErrorKind};
-use std::path::{Path, PathBuf};
 use std::process::{Command, Stdio};
 use std::sync::{Arc, OnceLock};
 use std::time::SystemTime;
 use std::{env, fs, vec};
 
 use build_helper::git::{get_git_modified_files, get_git_untracked_files};
+use camino::{Utf8Path, Utf8PathBuf};
 use getopts::Options;
 use tracing::*;
 use walkdir::WalkDir;
@@ -230,15 +229,19 @@ pub fn parse_config(args: Vec<String>) -> Config {
         panic!()
     }
 
-    fn opt_path(m: &getopts::Matches, nm: &str) -> PathBuf {
-        match m.opt_str(nm) {
-            Some(s) => PathBuf::from(&s),
-            None => panic!("no option (=path) found for {}", nm),
+    fn make_absolute(path: Utf8PathBuf) -> Utf8PathBuf {
+        if path.is_relative() {
+            Utf8PathBuf::try_from(env::current_dir().unwrap()).unwrap().join(path)
+        } else {
+            path
         }
     }
 
-    fn make_absolute(path: PathBuf) -> PathBuf {
-        if path.is_relative() { env::current_dir().unwrap().join(path) } else { path }
+    fn opt_path(m: &getopts::Matches, nm: &str) -> Utf8PathBuf {
+        match m.opt_str(nm) {
+            Some(s) => Utf8PathBuf::from(&s),
+            None => panic!("no option (=path) found for {}", nm),
+        }
     }
 
     let target = opt_str2(matches.opt_str("target"));
@@ -279,12 +282,12 @@ pub fn parse_config(args: Vec<String>) -> Config {
             .free
             .iter()
             .map(|f| {
-                let path = Path::new(f);
+                let path = Utf8Path::new(f);
                 let mut iter = path.iter().skip(1);
 
                 // We skip the test folder and check if the user passed `rmake.rs`.
                 if iter.next().is_some_and(|s| s == "rmake.rs") && iter.next().is_none() {
-                    path.parent().unwrap().to_str().unwrap().to_string()
+                    path.parent().unwrap().to_string()
                 } else {
                     f.to_string()
                 }
@@ -316,8 +319,8 @@ pub fn parse_config(args: Vec<String>) -> Config {
     assert!(
         src_test_suite_root.starts_with(&src_root),
         "`src-root` must be a parent of `src-test-suite-root`: `src-root`=`{}`, `src-test-suite-root` = `{}`",
-        src_root.display(),
-        src_test_suite_root.display()
+        src_root,
+        src_test_suite_root
     );
 
     let build_root = opt_path(matches, "build-root");
@@ -332,16 +335,16 @@ pub fn parse_config(args: Vec<String>) -> Config {
         compile_lib_path: make_absolute(opt_path(matches, "compile-lib-path")),
         run_lib_path: make_absolute(opt_path(matches, "run-lib-path")),
         rustc_path: opt_path(matches, "rustc-path"),
-        cargo_path: matches.opt_str("cargo-path").map(PathBuf::from),
-        stage0_rustc_path: matches.opt_str("stage0-rustc-path").map(PathBuf::from),
-        rustdoc_path: matches.opt_str("rustdoc-path").map(PathBuf::from),
-        coverage_dump_path: matches.opt_str("coverage-dump-path").map(PathBuf::from),
+        cargo_path: matches.opt_str("cargo-path").map(Utf8PathBuf::from),
+        stage0_rustc_path: matches.opt_str("stage0-rustc-path").map(Utf8PathBuf::from),
+        rustdoc_path: matches.opt_str("rustdoc-path").map(Utf8PathBuf::from),
+        coverage_dump_path: matches.opt_str("coverage-dump-path").map(Utf8PathBuf::from),
         python: matches.opt_str("python").unwrap(),
         jsondocck_path: matches.opt_str("jsondocck-path"),
         jsondoclint_path: matches.opt_str("jsondoclint-path"),
         run_clang_based_tests_with: matches.opt_str("run-clang-based-tests-with"),
-        llvm_filecheck: matches.opt_str("llvm-filecheck").map(PathBuf::from),
-        llvm_bin_dir: matches.opt_str("llvm-bin-dir").map(PathBuf::from),
+        llvm_filecheck: matches.opt_str("llvm-filecheck").map(Utf8PathBuf::from),
+        llvm_bin_dir: matches.opt_str("llvm-bin-dir").map(Utf8PathBuf::from),
 
         src_root,
         src_test_suite_root,
@@ -407,7 +410,7 @@ pub fn parse_config(args: Vec<String>) -> Config {
         },
         only_modified: matches.opt_present("only-modified"),
         color,
-        remote_test_client: matches.opt_str("remote-test-client").map(PathBuf::from),
+        remote_test_client: matches.opt_str("remote-test-client").map(Utf8PathBuf::from),
         compare_mode,
         rustfix_coverage: matches.opt_present("rustfix-coverage"),
         has_html_tidy,
@@ -450,19 +453,19 @@ pub fn parse_config(args: Vec<String>) -> Config {
 pub fn log_config(config: &Config) {
     let c = config;
     logv(c, "configuration:".to_string());
-    logv(c, format!("compile_lib_path: {:?}", config.compile_lib_path));
-    logv(c, format!("run_lib_path: {:?}", config.run_lib_path));
-    logv(c, format!("rustc_path: {:?}", config.rustc_path.display()));
+    logv(c, format!("compile_lib_path: {}", config.compile_lib_path));
+    logv(c, format!("run_lib_path: {}", config.run_lib_path));
+    logv(c, format!("rustc_path: {}", config.rustc_path));
     logv(c, format!("cargo_path: {:?}", config.cargo_path));
     logv(c, format!("rustdoc_path: {:?}", config.rustdoc_path));
 
-    logv(c, format!("src_root: {}", config.src_root.display()));
-    logv(c, format!("src_test_suite_root: {}", config.src_test_suite_root.display()));
+    logv(c, format!("src_root: {}", config.src_root));
+    logv(c, format!("src_test_suite_root: {}", config.src_test_suite_root));
 
-    logv(c, format!("build_root: {}", config.build_root.display()));
-    logv(c, format!("build_test_suite_root: {}", config.build_test_suite_root.display()));
+    logv(c, format!("build_root: {}", config.build_root));
+    logv(c, format!("build_test_suite_root: {}", config.build_test_suite_root));
 
-    logv(c, format!("sysroot_base: {}", config.sysroot_base.display()));
+    logv(c, format!("sysroot_base: {}", config.sysroot_base));
 
     logv(c, format!("stage: {}", config.stage));
     logv(c, format!("stage_id: {}", config.stage_id));
@@ -480,16 +483,16 @@ pub fn log_config(config: &Config) {
     logv(c, format!("target-rustcflags: {:?}", config.target_rustcflags));
     logv(c, format!("target: {}", config.target));
     logv(c, format!("host: {}", config.host));
-    logv(c, format!("android-cross-path: {:?}", config.android_cross_path.display()));
-    logv(c, format!("adb_path: {:?}", config.adb_path));
-    logv(c, format!("adb_test_dir: {:?}", config.adb_test_dir));
+    logv(c, format!("android-cross-path: {}", config.android_cross_path));
+    logv(c, format!("adb_path: {}", config.adb_path));
+    logv(c, format!("adb_test_dir: {}", config.adb_test_dir));
     logv(c, format!("adb_device_status: {}", config.adb_device_status));
     logv(c, format!("ar: {}", config.ar));
     logv(c, format!("target-linker: {:?}", config.target_linker));
     logv(c, format!("host-linker: {:?}", config.host_linker));
     logv(c, format!("verbose: {}", config.verbose));
     logv(c, format!("format: {:?}", config.format));
-    logv(c, format!("minicore_path: {:?}", config.minicore_path.display()));
+    logv(c, format!("minicore_path: {}", config.minicore_path));
     logv(c, "\n".to_string());
 }
 
@@ -517,7 +520,7 @@ pub fn run_tests(config: Arc<Config>) {
         coverage_file_path.push("rustfix_missing_coverage.txt");
         if coverage_file_path.exists() {
             if let Err(e) = fs::remove_file(&coverage_file_path) {
-                panic!("Could not delete {} due to {}", coverage_file_path.display(), e)
+                panic!("Could not delete {} due to {}", coverage_file_path, e)
             }
         }
     }
@@ -619,13 +622,13 @@ struct TestCollectorCx {
     config: Arc<Config>,
     cache: HeadersCache,
     common_inputs_stamp: Stamp,
-    modified_tests: Vec<PathBuf>,
+    modified_tests: Vec<Utf8PathBuf>,
 }
 
 /// Mutable state used during test collection.
 struct TestCollector {
     tests: Vec<CollectedTest>,
-    found_path_stems: HashSet<PathBuf>,
+    found_path_stems: HashSet<Utf8PathBuf>,
     poisoned: bool,
 }
 
@@ -635,14 +638,13 @@ struct TestCollector {
 /// regardless of whether any filters/tests were specified on the command-line,
 /// because filtering is handled later by libtest.
 pub(crate) fn collect_and_make_tests(config: Arc<Config>) -> Vec<CollectedTest> {
-    debug!("making tests from {}", config.src_test_suite_root.display());
+    debug!("making tests from {}", config.src_test_suite_root);
     let common_inputs_stamp = common_inputs_stamp(&config);
     let modified_tests =
         modified_tests(&config, &config.src_test_suite_root).unwrap_or_else(|err| {
             panic!(
                 "modified_tests got error from dir: {}, error: {}",
-                config.src_test_suite_root.display(),
-                err
+                config.src_test_suite_root, err
             )
         });
     let cache = HeadersCache::load(&config);
@@ -651,12 +653,9 @@ pub(crate) fn collect_and_make_tests(config: Arc<Config>) -> Vec<CollectedTest>
     let mut collector =
         TestCollector { tests: vec![], found_path_stems: HashSet::new(), poisoned: false };
 
-    collect_tests_from_dir(&cx, &mut collector, &cx.config.src_test_suite_root, Path::new(""))
+    collect_tests_from_dir(&cx, &mut collector, &cx.config.src_test_suite_root, Utf8Path::new(""))
         .unwrap_or_else(|reason| {
-            panic!(
-                "Could not read tests from {}: {reason}",
-                cx.config.src_test_suite_root.display()
-            )
+            panic!("Could not read tests from {}: {reason}", cx.config.src_test_suite_root)
         });
 
     let TestCollector { tests, found_path_stems, poisoned } = collector;
@@ -725,24 +724,29 @@ fn common_inputs_stamp(config: &Config) -> Stamp {
 /// the `--only-modified` flag is in use.
 ///
 /// (Might be inaccurate in some cases.)
-fn modified_tests(config: &Config, dir: &Path) -> Result<Vec<PathBuf>, String> {
+fn modified_tests(config: &Config, dir: &Utf8Path) -> Result<Vec<Utf8PathBuf>, String> {
     // If `--only-modified` wasn't passed, the list of modified tests won't be
     // used for anything, so avoid some work and just return an empty list.
     if !config.only_modified {
         return Ok(vec![]);
     }
 
-    let files =
-        get_git_modified_files(&config.git_config(), Some(dir), &vec!["rs", "stderr", "fixed"])?;
+    let files = get_git_modified_files(
+        &config.git_config(),
+        Some(dir.as_std_path()),
+        &vec!["rs", "stderr", "fixed"],
+    )?;
     // Add new test cases to the list, it will be convenient in daily development.
     let untracked_files = get_git_untracked_files(&config.git_config(), None)?.unwrap_or(vec![]);
 
     let all_paths = [&files[..], &untracked_files[..]].concat();
     let full_paths = {
-        let mut full_paths: Vec<PathBuf> = all_paths
+        let mut full_paths: Vec<Utf8PathBuf> = all_paths
             .into_iter()
-            .map(|f| PathBuf::from(f).with_extension("").with_extension("rs"))
-            .filter_map(|f| if Path::new(&f).exists() { f.canonicalize().ok() } else { None })
+            .map(|f| Utf8PathBuf::from(f).with_extension("").with_extension("rs"))
+            .filter_map(
+                |f| if Utf8Path::new(&f).exists() { f.canonicalize_utf8().ok() } else { None },
+            )
             .collect();
         full_paths.dedup();
         full_paths.sort_unstable();
@@ -756,8 +760,8 @@ fn modified_tests(config: &Config, dir: &Path) -> Result<Vec<PathBuf>, String> {
 fn collect_tests_from_dir(
     cx: &TestCollectorCx,
     collector: &mut TestCollector,
-    dir: &Path,
-    relative_dir_path: &Path,
+    dir: &Utf8Path,
+    relative_dir_path: &Utf8Path,
 ) -> io::Result<()> {
     // Ignore directories that contain a file named `compiletest-ignore-dir`.
     if dir.join("compiletest-ignore-dir").exists() {
@@ -790,16 +794,16 @@ fn collect_tests_from_dir(
     // subdirectories we find, except for `auxiliary` directories.
     // FIXME: this walks full tests tree, even if we have something to ignore
     // use walkdir/ignore like in tidy?
-    for file in fs::read_dir(dir)? {
+    for file in fs::read_dir(dir.as_std_path())? {
         let file = file?;
-        let file_path = file.path();
-        let file_name = file.file_name();
+        let file_path = Utf8PathBuf::try_from(file.path()).unwrap();
+        let file_name = file_path.file_name().unwrap();
 
-        if is_test(&file_name)
+        if is_test(file_name)
             && (!cx.config.only_modified || cx.modified_tests.contains(&file_path))
         {
             // We found a test file, so create the corresponding libtest structures.
-            debug!("found test file: {:?}", file_path.display());
+            debug!(%file_path, "found test file");
 
             // Record the stem of the test file, to check for overlaps later.
             let rel_test_path = relative_dir_path.join(file_path.file_stem().unwrap());
@@ -810,22 +814,20 @@ fn collect_tests_from_dir(
             make_test(cx, collector, &paths);
         } else if file_path.is_dir() {
             // Recurse to find more tests in a subdirectory.
-            let relative_file_path = relative_dir_path.join(file.file_name());
-            if &file_name != "auxiliary" {
-                debug!("found directory: {:?}", file_path.display());
+            let relative_file_path = relative_dir_path.join(file_name);
+            if file_name != "auxiliary" {
+                debug!(%file_path, "found directory");
                 collect_tests_from_dir(cx, collector, &file_path, &relative_file_path)?;
             }
         } else {
-            debug!("found other file/directory: {:?}", file_path.display());
+            debug!(%file_path, "found other file/directory");
         }
     }
     Ok(())
 }
 
 /// Returns true if `file_name` looks like a proper test file name.
-pub fn is_test(file_name: &OsString) -> bool {
-    let file_name = file_name.to_str().unwrap();
-
+pub fn is_test(file_name: &str) -> bool {
     if !file_name.ends_with(".rs") {
         return false;
     }
@@ -844,7 +846,7 @@ fn make_test(cx: &TestCollectorCx, collector: &mut TestCollector, testpaths: &Te
     let test_path = if cx.config.mode == Mode::RunMake {
         testpaths.file.join("rmake.rs")
     } else {
-        PathBuf::from(&testpaths.file)
+        testpaths.file.clone()
     };
 
     // Scan the test file to discover its revisions, if any.
@@ -899,7 +901,7 @@ fn make_test(cx: &TestCollectorCx, collector: &mut TestCollector, testpaths: &Te
 
 /// The path of the `stamp` file that gets created or updated whenever a
 /// particular test completes successfully.
-fn stamp_file_path(config: &Config, testpaths: &TestPaths, revision: Option<&str>) -> PathBuf {
+fn stamp_file_path(config: &Config, testpaths: &TestPaths, revision: Option<&str>) -> Utf8PathBuf {
     output_base_dir(config, testpaths, revision).join("stamp")
 }
 
@@ -912,7 +914,7 @@ fn files_related_to_test(
     testpaths: &TestPaths,
     props: &EarlyProps,
     revision: Option<&str>,
-) -> Vec<PathBuf> {
+) -> Vec<Utf8PathBuf> {
     let mut related = vec![];
 
     if testpaths.file.is_dir() {
@@ -920,7 +922,7 @@ fn files_related_to_test(
         for entry in WalkDir::new(&testpaths.file) {
             let path = entry.unwrap().into_path();
             if path.is_file() {
-                related.push(path);
+                related.push(Utf8PathBuf::try_from(path).unwrap());
             }
         }
     } else {
@@ -991,7 +993,7 @@ struct Stamp {
 
 impl Stamp {
     /// Creates a timestamp holding the last-modified time of the specified file.
-    fn from_path(path: &Path) -> Self {
+    fn from_path(path: &Utf8Path) -> Self {
         let mut stamp = Stamp { time: SystemTime::UNIX_EPOCH };
         stamp.add_path(path);
         stamp
@@ -999,8 +1001,8 @@ impl Stamp {
 
     /// Updates this timestamp to the last-modified time of the specified file,
     /// if it is later than the currently-stored timestamp.
-    fn add_path(&mut self, path: &Path) {
-        let modified = fs::metadata(path)
+    fn add_path(&mut self, path: &Utf8Path) {
+        let modified = fs::metadata(path.as_std_path())
             .and_then(|metadata| metadata.modified())
             .unwrap_or(SystemTime::UNIX_EPOCH);
         self.time = self.time.max(modified);
@@ -1009,7 +1011,8 @@ impl Stamp {
     /// Updates this timestamp to the most recent last-modified time of all files
     /// recursively contained in the given directory, if it is later than the
     /// currently-stored timestamp.
-    fn add_dir(&mut self, path: &Path) {
+    fn add_dir(&mut self, path: &Utf8Path) {
+        let path = path.as_std_path();
         for entry in WalkDir::new(path) {
             let entry = entry.unwrap();
             if entry.file_type().is_file() {
@@ -1042,7 +1045,7 @@ fn make_test_name(config: &Config, testpaths: &TestPaths, revision: Option<&str>
         config.mode,
         debugger,
         mode_suffix,
-        path.display(),
+        path,
         revision.map_or("".to_string(), |rev| format!("#{}", rev))
     )
 }
@@ -1064,7 +1067,7 @@ fn make_test_name(config: &Config, testpaths: &TestPaths, revision: Option<&str>
 /// To avoid problems, we forbid test names from overlapping in this way.
 ///
 /// See <https://github.com/rust-lang/rust/pull/109509> for more context.
-fn check_for_overlapping_test_paths(found_path_stems: &HashSet<PathBuf>) {
+fn check_for_overlapping_test_paths(found_path_stems: &HashSet<Utf8PathBuf>) {
     let mut collisions = Vec::new();
     for path in found_path_stems {
         for ancestor in path.ancestors().skip(1) {
@@ -1077,7 +1080,7 @@ fn check_for_overlapping_test_paths(found_path_stems: &HashSet<PathBuf>) {
         collisions.sort();
         let collisions: String = collisions
             .into_iter()
-            .map(|(path, check_parent)| format!("test {path:?} clashes with {check_parent:?}\n"))
+            .map(|(path, check_parent)| format!("test {path} clashes with {check_parent}\n"))
             .collect();
         panic!(
             "{collisions}\n\
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index 208d32833c9..722ba66e954 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -1,15 +1,15 @@
 use std::borrow::Cow;
 use std::collections::{HashMap, HashSet};
-use std::ffi::{OsStr, OsString};
+use std::ffi::OsString;
 use std::fs::{self, File, create_dir_all};
 use std::hash::{DefaultHasher, Hash, Hasher};
 use std::io::prelude::*;
 use std::io::{self, BufReader};
-use std::path::{Path, PathBuf};
 use std::process::{Child, Command, ExitStatus, Output, Stdio};
 use std::sync::Arc;
 use std::{env, iter, str};
 
+use camino::{Utf8Path, Utf8PathBuf};
 use colored::Colorize;
 use regex::{Captures, Regex};
 use tracing::*;
@@ -25,7 +25,7 @@ use crate::compute_diff::{DiffLine, make_diff, write_diff, write_filtered_diff};
 use crate::errors::{self, Error, ErrorKind};
 use crate::header::TestProps;
 use crate::read2::{Truncated, read2_abbreviated};
-use crate::util::{PathBufExt, add_dylib_path, logv, static_regex};
+use crate::util::{Utf8PathBufExt, add_dylib_path, logv, static_regex};
 use crate::{ColorConfig, json, stamp_file_path};
 
 mod debugger;
@@ -131,7 +131,7 @@ pub fn run(config: Arc<Config>, testpaths: &TestPaths, revision: Option<&str>) {
         // We're going to be dumping a lot of info. Start on a new line.
         print!("\n\n");
     }
-    debug!("running {:?}", testpaths.file.display());
+    debug!("running {}", testpaths.file);
     let mut props = TestProps::from_file(&testpaths.file, revision, &config);
 
     // For non-incremental (i.e. regular UI) tests, the incremental directory
@@ -144,7 +144,7 @@ pub fn run(config: Arc<Config>, testpaths: &TestPaths, revision: Option<&str>) {
     let cx = TestCx { config: &config, props: &props, testpaths, revision };
 
     if let Err(e) = create_dir_all(&cx.output_base_dir()) {
-        panic!("failed to create output base directory {}: {e}", cx.output_base_dir().display());
+        panic!("failed to create output base directory {}: {e}", cx.output_base_dir());
     }
 
     if props.incremental {
@@ -207,7 +207,8 @@ pub fn compute_stamp_hash(config: &Config) -> String {
     format!("{:x}", hash.finish())
 }
 
-fn remove_and_create_dir_all(path: &Path) {
+fn remove_and_create_dir_all(path: &Utf8Path) {
+    let path = path.as_std_path();
     let _ = fs::remove_dir_all(path);
     fs::create_dir_all(path).unwrap();
 }
@@ -423,7 +424,7 @@ impl<'test> TestCx<'test> {
         let aux_dir = self.aux_output_dir_name();
         let input: &str = match read_from {
             ReadFrom::Stdin(_) => "-",
-            ReadFrom::Path => self.testpaths.file.to_str().unwrap(),
+            ReadFrom::Path => self.testpaths.file.as_str(),
         };
 
         let mut rustc = Command::new(&self.config.rustc_path);
@@ -590,10 +591,7 @@ impl<'test> TestCx<'test> {
                 // FIXME(#65865)
                 return;
             } else {
-                self.fatal(&format!(
-                    "no error pattern specified in {:?}",
-                    self.testpaths.file.display()
-                ));
+                self.fatal(&format!("no error pattern specified in {}", self.testpaths.file));
             }
         }
 
@@ -697,17 +695,17 @@ impl<'test> TestCx<'test> {
         }
 
         // On Windows, translate all '\' path separators to '/'
-        let file_name = format!("{}", self.testpaths.file.display()).replace(r"\", "/");
+        let file_name = self.testpaths.file.to_string().replace(r"\", "/");
 
         // On Windows, keep all '\' path separators to match the paths reported in the JSON output
         // from the compiler
         let diagnostic_file_name = if self.props.remap_src_base {
-            let mut p = PathBuf::from(FAKE_SRC_BASE);
+            let mut p = Utf8PathBuf::from(FAKE_SRC_BASE);
             p.push(&self.testpaths.relative_dir);
             p.push(self.testpaths.file.file_name().unwrap());
-            p.display().to_string()
+            p.to_string()
         } else {
-            self.testpaths.file.display().to_string()
+            self.testpaths.file.to_string()
         };
 
         let expect_help = expected_errors.iter().any(|ee| ee.kind == Some(ErrorKind::Help));
@@ -887,7 +885,7 @@ impl<'test> TestCx<'test> {
 
     /// `root_out_dir` and `root_testpaths` refer to the parameters of the actual test being run.
     /// Auxiliaries, no matter how deep, have the same root_out_dir and root_testpaths.
-    fn document(&self, root_out_dir: &Path, root_testpaths: &TestPaths) -> ProcRes {
+    fn document(&self, root_out_dir: &Utf8Path, root_testpaths: &TestPaths) -> ProcRes {
         if self.props.build_aux_docs {
             for rel_ab in &self.props.aux.builds {
                 let aux_testpaths = self.compute_aux_test_paths(root_testpaths, rel_ab);
@@ -916,13 +914,13 @@ impl<'test> TestCx<'test> {
 
         // actual --out-dir given to the auxiliary or test, as opposed to the root out dir for the entire
         // test
-        let out_dir: Cow<'_, Path> = if self.props.unique_doc_out_dir {
+        let out_dir: Cow<'_, Utf8Path> = if self.props.unique_doc_out_dir {
             let file_name = self.testpaths.file.file_stem().expect("file name should not be empty");
-            let out_dir = PathBuf::from_iter([
+            let out_dir = Utf8PathBuf::from_iter([
                 root_out_dir,
-                Path::new("docs"),
-                Path::new(file_name),
-                Path::new("doc"),
+                Utf8Path::new("docs"),
+                Utf8Path::new(file_name),
+                Utf8Path::new("doc"),
             ]);
             create_dir_all(&out_dir).unwrap();
             Cow::Owned(out_dir)
@@ -935,7 +933,7 @@ impl<'test> TestCx<'test> {
         rustdoc.current_dir(current_dir);
         rustdoc
             .arg("-L")
-            .arg(self.config.run_lib_path.to_str().unwrap())
+            .arg(self.config.run_lib_path.as_path())
             .arg("-L")
             .arg(aux_dir)
             .arg("-o")
@@ -1073,7 +1071,7 @@ impl<'test> TestCx<'test> {
         let test_ab =
             of.file.parent().expect("test file path has no parent").join("auxiliary").join(rel_ab);
         if !test_ab.exists() {
-            self.fatal(&format!("aux-build `{}` source not found", test_ab.display()))
+            self.fatal(&format!("aux-build `{}` source not found", test_ab))
         }
 
         TestPaths {
@@ -1110,7 +1108,7 @@ impl<'test> TestCx<'test> {
             || !self.props.aux.proc_macros.is_empty()
     }
 
-    fn aux_output_dir(&self) -> PathBuf {
+    fn aux_output_dir(&self) -> Utf8PathBuf {
         let aux_dir = self.aux_output_dir_name();
 
         if !self.props.aux.builds.is_empty() {
@@ -1126,7 +1124,7 @@ impl<'test> TestCx<'test> {
         aux_dir
     }
 
-    fn build_all_auxiliary(&self, of: &TestPaths, aux_dir: &Path, rustc: &mut Command) {
+    fn build_all_auxiliary(&self, of: &TestPaths, aux_dir: &Utf8Path, rustc: &mut Command) {
         for rel_ab in &self.props.aux.builds {
             self.build_auxiliary(of, rel_ab, &aux_dir, None);
         }
@@ -1146,12 +1144,7 @@ impl<'test> TestCx<'test> {
             |rustc: &mut Command, aux_name: &str, aux_path: &str, aux_type: AuxType| {
                 let lib_name = get_lib_name(&path_to_crate_name(aux_path), aux_type);
                 if let Some(lib_name) = lib_name {
-                    rustc.arg("--extern").arg(format!(
-                        "{}={}/{}",
-                        aux_name,
-                        aux_dir.display(),
-                        lib_name
-                    ));
+                    rustc.arg("--extern").arg(format!("{}={}/{}", aux_name, aux_dir, lib_name));
                 }
             };
 
@@ -1172,7 +1165,7 @@ impl<'test> TestCx<'test> {
             let aux_type = self.build_auxiliary(of, aux_file, aux_dir, None);
             if let Some(lib_name) = get_lib_name(aux_file.trim_end_matches(".rs"), aux_type) {
                 let lib_path = aux_dir.join(&lib_name);
-                rustc.arg(format!("-Zcodegen-backend={}", lib_path.display()));
+                rustc.arg(format!("-Zcodegen-backend={}", lib_path));
             }
         }
     }
@@ -1188,7 +1181,7 @@ impl<'test> TestCx<'test> {
         if self.props.add_core_stubs {
             let minicore_path = self.build_minicore();
             rustc.arg("--extern");
-            rustc.arg(&format!("minicore={}", minicore_path.to_str().unwrap()));
+            rustc.arg(&format!("minicore={}", minicore_path));
         }
 
         let aux_dir = self.aux_output_dir();
@@ -1206,7 +1199,7 @@ impl<'test> TestCx<'test> {
 
     /// Builds `minicore`. Returns the path to the minicore rlib within the base test output
     /// directory.
-    fn build_minicore(&self) -> PathBuf {
+    fn build_minicore(&self) -> Utf8PathBuf {
         let output_file_path = self.output_base_dir().join("libminicore.rlib");
         let mut rustc = self.make_compile_args(
             &self.config.minicore_path,
@@ -1223,10 +1216,7 @@ impl<'test> TestCx<'test> {
         let res = self.compose_and_run(rustc, self.config.compile_lib_path.as_path(), None, None);
         if !res.status.success() {
             self.fatal_proc_rec(
-                &format!(
-                    "auxiliary build of {:?} failed to compile: ",
-                    self.config.minicore_path.display()
-                ),
+                &format!("auxiliary build of {} failed to compile: ", self.config.minicore_path),
                 &res,
             );
         }
@@ -1241,7 +1231,7 @@ impl<'test> TestCx<'test> {
         &self,
         of: &TestPaths,
         source_path: &str,
-        aux_dir: &Path,
+        aux_dir: &Utf8Path,
         aux_type: Option<AuxType>,
     ) -> AuxType {
         let aux_testpaths = self.compute_aux_test_paths(of, source_path);
@@ -1338,10 +1328,7 @@ impl<'test> TestCx<'test> {
         );
         if !auxres.status.success() {
             self.fatal_proc_rec(
-                &format!(
-                    "auxiliary build of {:?} failed to compile: ",
-                    aux_testpaths.file.display()
-                ),
+                &format!("auxiliary build of {} failed to compile: ", aux_testpaths.file),
                 &auxres,
             );
         }
@@ -1350,8 +1337,8 @@ impl<'test> TestCx<'test> {
 
     fn read2_abbreviated(&self, child: Child) -> (Output, Truncated) {
         let mut filter_paths_from_len = Vec::new();
-        let mut add_path = |path: &Path| {
-            let path = path.display().to_string();
+        let mut add_path = |path: &Utf8Path| {
+            let path = path.to_string();
             let windows = path.replace("\\", "\\\\");
             if windows != path {
                 filter_paths_from_len.push(windows);
@@ -1373,8 +1360,8 @@ impl<'test> TestCx<'test> {
     fn compose_and_run(
         &self,
         mut command: Command,
-        lib_path: &Path,
-        aux_path: Option<&Path>,
+        lib_path: &Utf8Path,
+        aux_path: Option<&Utf8Path>,
         input: Option<String>,
     ) -> ProcRes {
         let cmdline = {
@@ -1419,9 +1406,9 @@ impl<'test> TestCx<'test> {
         matches!(self.config.suite.as_str(), "rustdoc-ui" | "rustdoc-js" | "rustdoc-json")
     }
 
-    fn get_mir_dump_dir(&self) -> PathBuf {
+    fn get_mir_dump_dir(&self) -> Utf8PathBuf {
         let mut mir_dump_dir = self.config.build_test_suite_root.clone();
-        debug!("input_file: {:?}", self.testpaths.file);
+        debug!("input_file: {}", self.testpaths.file);
         mir_dump_dir.push(&self.testpaths.relative_dir);
         mir_dump_dir.push(self.testpaths.file.file_stem().unwrap());
         mir_dump_dir
@@ -1429,7 +1416,7 @@ impl<'test> TestCx<'test> {
 
     fn make_compile_args(
         &self,
-        input_file: &Path,
+        input_file: &Utf8Path,
         output_file: TargetLocation,
         emit: Emit,
         allow_unused: AllowUnused,
@@ -1470,7 +1457,7 @@ impl<'test> TestCx<'test> {
         // Similarly, vendored sources shouldn't be shown when running from a dist tarball.
         rustc.arg("-Z").arg(format!(
             "ignore-directory-in-diagnostics-source-blocks={}",
-            self.config.src_root.join("vendor").to_str().unwrap(),
+            self.config.src_root.join("vendor"),
         ));
 
         // Optionally prevent default --sysroot if specified in test compile-flags.
@@ -1494,7 +1481,7 @@ impl<'test> TestCx<'test> {
 
         if !is_rustdoc {
             if let Some(ref incremental_dir) = self.props.incremental_dir {
-                rustc.args(&["-C", &format!("incremental={}", incremental_dir.display())]);
+                rustc.args(&["-C", &format!("incremental={}", incremental_dir)]);
                 rustc.args(&["-Z", "incremental-verify-ich"]);
             }
 
@@ -1538,7 +1525,7 @@ impl<'test> TestCx<'test> {
             let mir_dump_dir = self.get_mir_dump_dir();
             remove_and_create_dir_all(&mir_dump_dir);
             let mut dir_opt = "-Zdump-mir-dir=".to_string();
-            dir_opt.push_str(mir_dump_dir.to_str().unwrap());
+            dir_opt.push_str(mir_dump_dir.as_str());
             debug!("dir_opt: {:?}", dir_opt);
             rustc.arg(dir_opt);
         };
@@ -1631,8 +1618,7 @@ impl<'test> TestCx<'test> {
         if self.props.remap_src_base {
             rustc.arg(format!(
                 "--remap-path-prefix={}={}",
-                self.config.src_test_suite_root.to_str().unwrap(),
-                FAKE_SRC_BASE,
+                self.config.src_test_suite_root, FAKE_SRC_BASE,
             ));
         }
 
@@ -1755,7 +1741,7 @@ impl<'test> TestCx<'test> {
         rustc
     }
 
-    fn make_exe_name(&self) -> PathBuf {
+    fn make_exe_name(&self) -> Utf8PathBuf {
         // Using a single letter here to keep the path length down for
         // Windows.  Some test names get very long.  rustc creates `rcgu`
         // files with the module name appended to it which can more than
@@ -1806,7 +1792,7 @@ impl<'test> TestCx<'test> {
         }
     }
 
-    fn make_cmdline(&self, command: &Command, libpath: &Path) -> String {
+    fn make_cmdline(&self, command: &Command, libpath: &Utf8Path) -> String {
         use crate::util;
 
         // Linux and mac don't require adjusting the library search path
@@ -1819,7 +1805,7 @@ impl<'test> TestCx<'test> {
                 format!("{}=\"{}\"", util::lib_path_env_var(), util::make_new_path(path))
             }
 
-            format!("{} {:?}", lib_path_cmd_prefix(libpath.to_str().unwrap()), command)
+            format!("{} {:?}", lib_path_cmd_prefix(libpath.as_str()), command)
         }
     }
 
@@ -1833,20 +1819,19 @@ impl<'test> TestCx<'test> {
             return;
         }
 
-        let path = Path::new(proc_name);
+        let path = Utf8Path::new(proc_name);
         let proc_name = if path.file_stem().is_some_and(|p| p == "rmake") {
-            OsString::from_iter(
+            String::from_iter(
                 path.parent()
                     .unwrap()
                     .file_name()
                     .into_iter()
-                    .chain(Some(OsStr::new("/")))
+                    .chain(Some("/"))
                     .chain(path.file_name()),
             )
         } else {
             path.file_name().unwrap().into()
         };
-        let proc_name = proc_name.to_string_lossy();
         println!("------{proc_name} stdout------------------------------");
         println!("{}", out);
         println!("------{proc_name} stderr------------------------------");
@@ -1856,18 +1841,18 @@ impl<'test> TestCx<'test> {
 
     fn dump_output_file(&self, out: &str, extension: &str) {
         let outfile = self.make_out_name(extension);
-        fs::write(&outfile, out).unwrap();
+        fs::write(outfile.as_std_path(), out).unwrap();
     }
 
     /// Creates a filename for output with the given extension.
     /// E.g., `/.../testname.revision.mode/testname.extension`.
-    fn make_out_name(&self, extension: &str) -> PathBuf {
+    fn make_out_name(&self, extension: &str) -> Utf8PathBuf {
         self.output_base_name().with_extension(extension)
     }
 
     /// Gets the directory where auxiliary files are written.
     /// E.g., `/.../testname.revision.mode/auxiliary/`.
-    fn aux_output_dir_name(&self) -> PathBuf {
+    fn aux_output_dir_name(&self) -> Utf8PathBuf {
         self.output_base_dir()
             .join("auxiliary")
             .with_extra_extension(self.config.mode.aux_dir_disambiguator())
@@ -1875,12 +1860,12 @@ impl<'test> TestCx<'test> {
 
     /// Gets the directory where auxiliary binaries are written.
     /// E.g., `/.../testname.revision.mode/auxiliary/bin`.
-    fn aux_bin_output_dir_name(&self) -> PathBuf {
+    fn aux_bin_output_dir_name(&self) -> Utf8PathBuf {
         self.aux_output_dir_name().join("bin")
     }
 
     /// Generates a unique name for the test, such as `testname.revision.mode`.
-    fn output_testname_unique(&self) -> PathBuf {
+    fn output_testname_unique(&self) -> Utf8PathBuf {
         output_testname_unique(self.config, self.testpaths, self.safe_revision())
     }
 
@@ -1893,14 +1878,14 @@ impl<'test> TestCx<'test> {
     /// Gets the absolute path to the directory where all output for the given
     /// test/revision should reside.
     /// E.g., `/path/to/build/host-tuple/test/ui/relative/testname.revision.mode/`.
-    fn output_base_dir(&self) -> PathBuf {
+    fn output_base_dir(&self) -> Utf8PathBuf {
         output_base_dir(self.config, self.testpaths, self.safe_revision())
     }
 
     /// Gets the absolute path to the base filename used as output for the given
     /// test/revision.
     /// E.g., `/.../relative/testname.revision.mode/testname`.
-    fn output_base_name(&self) -> PathBuf {
+    fn output_base_name(&self) -> Utf8PathBuf {
         output_base_name(self.config, self.testpaths, self.safe_revision())
     }
 
@@ -1935,7 +1920,7 @@ impl<'test> TestCx<'test> {
 
     // codegen tests (using FileCheck)
 
-    fn compile_test_and_save_ir(&self) -> (ProcRes, PathBuf) {
+    fn compile_test_and_save_ir(&self) -> (ProcRes, Utf8PathBuf) {
         let output_path = self.output_base_name().with_extension("ll");
         let input_file = &self.testpaths.file;
         let rustc = self.make_compile_args(
@@ -1951,7 +1936,7 @@ impl<'test> TestCx<'test> {
         (proc_res, output_path)
     }
 
-    fn verify_with_filecheck(&self, output: &Path) -> ProcRes {
+    fn verify_with_filecheck(&self, output: &Utf8Path) -> ProcRes {
         let mut filecheck = Command::new(self.config.llvm_filecheck.as_ref().unwrap());
         filecheck.arg("--input-file").arg(output).arg(&self.testpaths.file);
 
@@ -1981,7 +1966,7 @@ impl<'test> TestCx<'test> {
         filecheck.args(&self.props.filecheck_flags);
 
         // FIXME(jieyouxu): don't pass an empty Path
-        self.compose_and_run(filecheck, Path::new(""), None, None)
+        self.compose_and_run(filecheck, Utf8Path::new(""), None, None)
     }
 
     fn charset() -> &'static str {
@@ -1989,7 +1974,7 @@ impl<'test> TestCx<'test> {
         if cfg!(target_os = "freebsd") { "ISO-8859-1" } else { "UTF-8" }
     }
 
-    fn compare_to_default_rustdoc(&mut self, out_dir: &Path) {
+    fn compare_to_default_rustdoc(&mut self, out_dir: &Utf8Path) {
         if !self.config.has_html_tidy {
             return;
         }
@@ -2141,12 +2126,8 @@ impl<'test> TestCx<'test> {
         };
     }
 
-    fn get_lines<P: AsRef<Path>>(
-        &self,
-        path: &P,
-        mut other_files: Option<&mut Vec<String>>,
-    ) -> Vec<usize> {
-        let content = fs::read_to_string(&path).unwrap();
+    fn get_lines(&self, path: &Utf8Path, mut other_files: Option<&mut Vec<String>>) -> Vec<usize> {
+        let content = fs::read_to_string(path.as_std_path()).unwrap();
         let mut ignore = false;
         content
             .lines()
@@ -2192,8 +2173,8 @@ impl<'test> TestCx<'test> {
         for other_file in other_files {
             let mut path = self.testpaths.file.clone();
             path.set_file_name(&format!("{}.rs", other_file));
-            let path = fs::canonicalize(path).expect("failed to canonicalize");
-            let normalized = path.to_str().unwrap().replace('\\', "/");
+            let path = path.canonicalize_utf8().expect("failed to canonicalize");
+            let normalized = path.as_str().replace('\\', "/");
             files.insert(normalized, self.get_lines(&path, None));
         }
 
@@ -2377,26 +2358,24 @@ impl<'test> TestCx<'test> {
 
         let mut normalized = output.to_string();
 
-        let mut normalize_path = |from: &Path, to: &str| {
-            let mut from = from.display().to_string();
-            if json {
-                from = from.replace("\\", "\\\\");
-            }
-            normalized = normalized.replace(&from, to);
+        let mut normalize_path = |from: &Utf8Path, to: &str| {
+            let from = if json { &from.as_str().replace("\\", "\\\\") } else { from.as_str() };
+
+            normalized = normalized.replace(from, to);
         };
 
         let parent_dir = self.testpaths.file.parent().unwrap();
         normalize_path(parent_dir, "$DIR");
 
         if self.props.remap_src_base {
-            let mut remapped_parent_dir = PathBuf::from(FAKE_SRC_BASE);
-            if self.testpaths.relative_dir != Path::new("") {
+            let mut remapped_parent_dir = Utf8PathBuf::from(FAKE_SRC_BASE);
+            if self.testpaths.relative_dir != Utf8Path::new("") {
                 remapped_parent_dir.push(&self.testpaths.relative_dir);
             }
             normalize_path(&remapped_parent_dir, "$DIR");
         }
 
-        let base_dir = Path::new("/rustc/FAKE_PREFIX");
+        let base_dir = Utf8Path::new("/rustc/FAKE_PREFIX");
         // Fake paths into the libstd/libcore
         normalize_path(&base_dir.join("library"), "$SRC_DIR");
         // `ui-fulldeps` tests can show paths to the compiler source when testing macros from
@@ -2406,8 +2385,8 @@ impl<'test> TestCx<'test> {
 
         // Real paths into the libstd/libcore
         let rust_src_dir = &self.config.sysroot_base.join("lib/rustlib/src/rust");
-        rust_src_dir.try_exists().expect(&*format!("{} should exists", rust_src_dir.display()));
-        let rust_src_dir = rust_src_dir.read_link().unwrap_or(rust_src_dir.to_path_buf());
+        rust_src_dir.try_exists().expect(&*format!("{} should exists", rust_src_dir));
+        let rust_src_dir = rust_src_dir.read_link_utf8().unwrap_or(rust_src_dir.to_path_buf());
         normalize_path(&rust_src_dir.join("library"), "$SRC_DIR_REAL");
 
         // eg.
@@ -2547,7 +2526,7 @@ impl<'test> TestCx<'test> {
             .replace("\r\n", "\n")
     }
 
-    fn expected_output_path(&self, kind: &str) -> PathBuf {
+    fn expected_output_path(&self, kind: &str) -> Utf8PathBuf {
         let mut path =
             expected_output_path(&self.testpaths, self.revision, &self.config.compare_mode, kind);
 
@@ -2576,19 +2555,18 @@ impl<'test> TestCx<'test> {
         }
     }
 
-    fn load_expected_output_from_path(&self, path: &Path) -> Result<String, String> {
-        fs::read_to_string(path).map_err(|err| {
-            format!("failed to load expected output from `{}`: {}", path.display(), err)
-        })
+    fn load_expected_output_from_path(&self, path: &Utf8Path) -> Result<String, String> {
+        fs::read_to_string(path)
+            .map_err(|err| format!("failed to load expected output from `{}`: {}", path, err))
     }
 
-    fn delete_file(&self, file: &Path) {
+    fn delete_file(&self, file: &Utf8Path) {
         if !file.exists() {
             // Deleting a nonexistent file would error.
             return;
         }
-        if let Err(e) = fs::remove_file(file) {
-            self.fatal(&format!("failed to delete `{}`: {}", file.display(), e,));
+        if let Err(e) = fs::remove_file(file.as_std_path()) {
+            self.fatal(&format!("failed to delete `{}`: {}", file, e,));
         }
     }
 
@@ -2694,8 +2672,8 @@ impl<'test> TestCx<'test> {
     fn show_diff(
         &self,
         stream: &str,
-        expected_path: &Path,
-        actual_path: &Path,
+        expected_path: &Utf8Path,
+        actual_path: &Utf8Path,
         expected: &str,
         actual: &str,
         actual_unnormalized: &str,
@@ -2834,7 +2812,7 @@ impl<'test> TestCx<'test> {
         fs::create_dir_all(&incremental_dir).unwrap();
 
         if self.config.verbose {
-            println!("init_incremental_test: incremental_dir={}", incremental_dir.display());
+            println!("init_incremental_test: incremental_dir={incremental_dir}");
         }
     }
 }
@@ -2892,8 +2870,8 @@ impl ProcRes {
 
 #[derive(Debug)]
 enum TargetLocation {
-    ThisFile(PathBuf),
-    ThisDirectory(PathBuf),
+    ThisFile(Utf8PathBuf),
+    ThisDirectory(Utf8PathBuf),
 }
 
 enum AllowUnused {
diff --git a/src/tools/compiletest/src/runtest/assembly.rs b/src/tools/compiletest/src/runtest/assembly.rs
index 89d7de58c20..91d4f620f71 100644
--- a/src/tools/compiletest/src/runtest/assembly.rs
+++ b/src/tools/compiletest/src/runtest/assembly.rs
@@ -1,4 +1,4 @@
-use std::path::PathBuf;
+use camino::Utf8PathBuf;
 
 use super::{AllowUnused, Emit, LinkToAux, ProcRes, TargetLocation, TestCx};
 
@@ -19,7 +19,7 @@ impl TestCx<'_> {
         }
     }
 
-    fn compile_test_and_save_assembly(&self) -> (ProcRes, PathBuf) {
+    fn compile_test_and_save_assembly(&self) -> (ProcRes, Utf8PathBuf) {
         // This works with both `--emit asm` (as default output name for the assembly)
         // and `ptx-linker` because the latter can write output at requested location.
         let output_path = self.output_base_name().with_extension("s");
diff --git a/src/tools/compiletest/src/runtest/codegen_units.rs b/src/tools/compiletest/src/runtest/codegen_units.rs
index 6c866cbef21..8dfa8d18d1a 100644
--- a/src/tools/compiletest/src/runtest/codegen_units.rs
+++ b/src/tools/compiletest/src/runtest/codegen_units.rs
@@ -26,9 +26,7 @@ impl TestCx<'_> {
             .stdout
             .lines()
             .filter(|line| line.starts_with(PREFIX))
-            .map(|line| {
-                line.replace(&self.testpaths.file.display().to_string(), "TEST_PATH").to_string()
-            })
+            .map(|line| line.replace(&self.testpaths.file.as_str(), "TEST_PATH").to_string())
             .map(|line| str_to_mono_item(&line, true))
             .collect();
 
diff --git a/src/tools/compiletest/src/runtest/coverage.rs b/src/tools/compiletest/src/runtest/coverage.rs
index 56fc5baf5f2..41cfeaee35f 100644
--- a/src/tools/compiletest/src/runtest/coverage.rs
+++ b/src/tools/compiletest/src/runtest/coverage.rs
@@ -1,9 +1,9 @@
 //! Code specific to the coverage test suites.
 
 use std::ffi::OsStr;
-use std::path::{Path, PathBuf};
 use std::process::Command;
 
+use camino::{Utf8Path, Utf8PathBuf};
 use glob::glob;
 
 use crate::common::{UI_COVERAGE, UI_COVERAGE_MAP};
@@ -11,7 +11,7 @@ use crate::runtest::{Emit, ProcRes, TestCx, WillExecute};
 use crate::util::static_regex;
 
 impl<'test> TestCx<'test> {
-    fn coverage_dump_path(&self) -> &Path {
+    fn coverage_dump_path(&self) -> &Utf8Path {
         self.config
             .coverage_dump_path
             .as_deref()
@@ -79,10 +79,8 @@ impl<'test> TestCx<'test> {
             std::fs::remove_file(&profdata_path).unwrap();
         }
 
-        let proc_res = self.exec_compiled_test_general(
-            &[("LLVM_PROFILE_FILE", &profraw_path.to_str().unwrap())],
-            false,
-        );
+        let proc_res =
+            self.exec_compiled_test_general(&[("LLVM_PROFILE_FILE", profraw_path.as_str())], false);
         if self.props.failure_status.is_some() {
             self.check_correct_failure_status(&proc_res);
         } else if !proc_res.status.success() {
@@ -158,8 +156,8 @@ impl<'test> TestCx<'test> {
     /// `.profraw` files and doctest executables to the given vectors.
     fn run_doctests_for_coverage(
         &self,
-        profraw_paths: &mut Vec<PathBuf>,
-        bin_paths: &mut Vec<PathBuf>,
+        profraw_paths: &mut Vec<Utf8PathBuf>,
+        bin_paths: &mut Vec<Utf8PathBuf>,
     ) {
         // Put .profraw files and doctest executables in dedicated directories,
         // to make it easier to glob them all later.
@@ -204,10 +202,9 @@ impl<'test> TestCx<'test> {
             self.fatal_proc_rec("rustdoc --test failed!", &proc_res)
         }
 
-        fn glob_iter(path: impl AsRef<Path>) -> impl Iterator<Item = PathBuf> {
-            let path_str = path.as_ref().to_str().unwrap();
-            let iter = glob(path_str).unwrap();
-            iter.map(Result::unwrap)
+        fn glob_iter(path: impl AsRef<Utf8Path>) -> impl Iterator<Item = Utf8PathBuf> {
+            let iter = glob(path.as_ref().as_str()).unwrap();
+            iter.map(Result::unwrap).map(Utf8PathBuf::try_from).map(Result::unwrap)
         }
 
         // Find all profraw files in the profraw directory.
diff --git a/src/tools/compiletest/src/runtest/debugger.rs b/src/tools/compiletest/src/runtest/debugger.rs
index d9e5c3fa0d8..a4103c5b4a9 100644
--- a/src/tools/compiletest/src/runtest/debugger.rs
+++ b/src/tools/compiletest/src/runtest/debugger.rs
@@ -1,7 +1,8 @@
 use std::fmt::Write;
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::path::{Path, PathBuf};
+
+use camino::{Utf8Path, Utf8PathBuf};
 
 use crate::common::Config;
 use crate::runtest::ProcRes;
@@ -15,11 +16,15 @@ pub(super) struct DebuggerCommands {
     /// Contains the source line number to check and the line itself
     check_lines: Vec<(usize, String)>,
     /// Source file name
-    file: PathBuf,
+    file: Utf8PathBuf,
 }
 
 impl DebuggerCommands {
-    pub fn parse_from(file: &Path, config: &Config, debugger_prefix: &str) -> Result<Self, String> {
+    pub fn parse_from(
+        file: &Utf8Path,
+        config: &Config,
+        debugger_prefix: &str,
+    ) -> Result<Self, String> {
         let command_directive = format!("{debugger_prefix}-command");
         let check_directive = format!("{debugger_prefix}-check");
 
@@ -27,7 +32,7 @@ impl DebuggerCommands {
         let mut commands = vec![];
         let mut check_lines = vec![];
         let mut counter = 0;
-        let reader = BufReader::new(File::open(file).unwrap());
+        let reader = BufReader::new(File::open(file.as_std_path()).unwrap());
         for (line_no, line) in reader.lines().enumerate() {
             counter += 1;
             let line = line.map_err(|e| format!("Error while parsing debugger commands: {}", e))?;
@@ -50,7 +55,7 @@ impl DebuggerCommands {
             }
         }
 
-        Ok(Self { commands, breakpoint_lines, check_lines, file: file.to_owned() })
+        Ok(Self { commands, breakpoint_lines, check_lines, file: file.to_path_buf() })
     }
 
     /// Given debugger output and lines to check, ensure that every line is
@@ -81,10 +86,10 @@ impl DebuggerCommands {
         if missing.is_empty() {
             Ok(())
         } else {
-            let fname = self.file.file_name().unwrap().to_string_lossy();
+            let fname = self.file.file_name().unwrap();
             let mut msg = format!(
                 "check directive(s) from `{}` not found in debugger output. errors:",
-                self.file.display()
+                self.file
             );
 
             for (src_lineno, err_line) in missing {
diff --git a/src/tools/compiletest/src/runtest/debuginfo.rs b/src/tools/compiletest/src/runtest/debuginfo.rs
index 50e733cd31b..31240dff9a1 100644
--- a/src/tools/compiletest/src/runtest/debuginfo.rs
+++ b/src/tools/compiletest/src/runtest/debuginfo.rs
@@ -1,9 +1,9 @@
 use std::ffi::{OsStr, OsString};
 use std::fs::File;
 use std::io::{BufRead, BufReader, Read};
-use std::path::Path;
 use std::process::{Command, Output, Stdio};
 
+use camino::Utf8Path;
 use tracing::debug;
 
 use super::debugger::DebuggerCommands;
@@ -73,11 +73,11 @@ impl TestCx<'_> {
         let mut js_extension = self.testpaths.file.clone();
         js_extension.set_extension("cdb.js");
         if js_extension.exists() {
-            script_str.push_str(&format!(".scriptload \"{}\"\n", js_extension.to_string_lossy()));
+            script_str.push_str(&format!(".scriptload \"{}\"\n", js_extension));
         }
 
         // Set breakpoints on every line that contains the string "#break"
-        let source_file_name = self.testpaths.file.file_name().unwrap().to_string_lossy();
+        let source_file_name = self.testpaths.file.file_name().unwrap();
         for line in &dbg_cmds.breakpoint_lines {
             script_str.push_str(&format!("bp `{}:{}`\n", source_file_name, line));
         }
@@ -151,16 +151,11 @@ impl TestCx<'_> {
         if is_android_gdb_target(&self.config.target) {
             cmds = cmds.replace("run", "continue");
 
-            let tool_path = match self.config.android_cross_path.to_str() {
-                Some(x) => x.to_owned(),
-                None => self.fatal("cannot find android cross path"),
-            };
-
             // write debugger script
             let mut script_str = String::with_capacity(2048);
             script_str.push_str(&format!("set charset {}\n", Self::charset()));
-            script_str.push_str(&format!("set sysroot {}\n", tool_path));
-            script_str.push_str(&format!("file {}\n", exe_file.to_str().unwrap()));
+            script_str.push_str(&format!("set sysroot {}\n", &self.config.android_cross_path));
+            script_str.push_str(&format!("file {}\n", exe_file));
             script_str.push_str("target remote :5039\n");
             script_str.push_str(&format!(
                 "set solib-search-path \
@@ -169,12 +164,8 @@ impl TestCx<'_> {
             ));
             for line in &dbg_cmds.breakpoint_lines {
                 script_str.push_str(
-                    format!(
-                        "break {:?}:{}\n",
-                        self.testpaths.file.file_name().unwrap().to_string_lossy(),
-                        *line
-                    )
-                    .as_str(),
+                    format!("break {}:{}\n", self.testpaths.file.file_name().unwrap(), *line)
+                        .as_str(),
                 );
             }
             script_str.push_str(&cmds);
@@ -203,7 +194,7 @@ impl TestCx<'_> {
                 self.config.adb_test_dir.clone(),
                 if self.config.target.contains("aarch64") { "64" } else { "" },
                 self.config.adb_test_dir.clone(),
-                exe_file.file_name().unwrap().to_str().unwrap()
+                exe_file.file_name().unwrap()
             );
 
             debug!("adb arg: {}", adb_arg);
@@ -242,7 +233,7 @@ impl TestCx<'_> {
                 let mut gdb = Command::new(&format!("{}-gdb", self.config.target));
                 gdb.args(debugger_opts);
                 // FIXME(jieyouxu): don't pass an empty Path
-                let cmdline = self.make_cmdline(&gdb, Path::new(""));
+                let cmdline = self.make_cmdline(&gdb, Utf8Path::new(""));
                 logv(self.config, format!("executing {}", cmdline));
                 cmdline
             };
@@ -259,7 +250,6 @@ impl TestCx<'_> {
             }
         } else {
             let rust_pp_module_abs_path = self.config.src_root.join("src").join("etc");
-            let rust_pp_module_abs_path = rust_pp_module_abs_path.to_str().unwrap();
             // write debugger script
             let mut script_str = String::with_capacity(2048);
             script_str.push_str(&format!("set charset {}\n", Self::charset()));
@@ -274,17 +264,15 @@ impl TestCx<'_> {
                         // GDB's script auto loading safe path
                         script_str.push_str(&format!(
                             "add-auto-load-safe-path {}\n",
-                            rust_pp_module_abs_path.replace(r"\", r"\\")
+                            rust_pp_module_abs_path.as_str().replace(r"\", r"\\")
                         ));
 
-                        let output_base_dir = self.output_base_dir().to_str().unwrap().to_owned();
-
                         // Add the directory containing the output binary to
                         // include embedded pretty printers to GDB's script
                         // auto loading safe path
                         script_str.push_str(&format!(
                             "add-auto-load-safe-path {}\n",
-                            output_base_dir.replace(r"\", r"\\")
+                            self.output_base_dir().as_str().replace(r"\", r"\\")
                         ));
                     }
                 }
@@ -301,12 +289,13 @@ impl TestCx<'_> {
             script_str.push_str("set print pretty off\n");
 
             // Add the pretty printer directory to GDB's source-file search path
-            script_str
-                .push_str(&format!("directory {}\n", rust_pp_module_abs_path.replace(r"\", r"\\")));
+            script_str.push_str(&format!(
+                "directory {}\n",
+                rust_pp_module_abs_path.as_str().replace(r"\", r"\\")
+            ));
 
             // Load the target executable
-            script_str
-                .push_str(&format!("file {}\n", exe_file.to_str().unwrap().replace(r"\", r"\\")));
+            script_str.push_str(&format!("file {}\n", exe_file.as_str().replace(r"\", r"\\")));
 
             // Force GDB to print values in the Rust format.
             script_str.push_str("set language rust\n");
@@ -315,7 +304,7 @@ impl TestCx<'_> {
             for line in &dbg_cmds.breakpoint_lines {
                 script_str.push_str(&format!(
                     "break '{}':{}\n",
-                    self.testpaths.file.file_name().unwrap().to_string_lossy(),
+                    self.testpaths.file.file_name().unwrap(),
                     *line
                 ));
             }
@@ -410,14 +399,14 @@ impl TestCx<'_> {
 
         script_str.push_str(&format!(
             "command script import {}/lldb_lookup.py\n",
-            rust_pp_module_abs_path.to_str().unwrap()
+            rust_pp_module_abs_path
         ));
         File::open(rust_pp_module_abs_path.join("lldb_commands"))
             .and_then(|mut file| file.read_to_string(&mut script_str))
             .expect("Failed to read lldb_commands");
 
         // Set breakpoints on every line that contains the string "#break"
-        let source_file_name = self.testpaths.file.file_name().unwrap().to_string_lossy();
+        let source_file_name = self.testpaths.file.file_name().unwrap();
         for line in &dbg_cmds.breakpoint_lines {
             script_str.push_str(&format!(
                 "breakpoint set --file '{}' --line {}\n",
@@ -451,7 +440,7 @@ impl TestCx<'_> {
         }
     }
 
-    fn run_lldb(&self, test_executable: &Path, debugger_script: &Path) -> ProcRes {
+    fn run_lldb(&self, test_executable: &Utf8Path, debugger_script: &Utf8Path) -> ProcRes {
         // Prepare the lldb_batchmode which executes the debugger script
         let lldb_script_path = self.config.src_root.join("src/etc/lldb_batchmode.py");
         let pythonpath = if let Ok(pp) = std::env::var("PYTHONPATH") {
diff --git a/src/tools/compiletest/src/runtest/js_doc.rs b/src/tools/compiletest/src/runtest/js_doc.rs
index d630affbec1..fd53f01ca17 100644
--- a/src/tools/compiletest/src/runtest/js_doc.rs
+++ b/src/tools/compiletest/src/runtest/js_doc.rs
@@ -9,8 +9,7 @@ impl TestCx<'_> {
 
             self.document(&out_dir, &self.testpaths);
 
-            let file_stem =
-                self.testpaths.file.file_stem().and_then(|f| f.to_str()).expect("no file stem");
+            let file_stem = self.testpaths.file.file_stem().expect("no file stem");
             let res = self.run_command_to_procres(
                 Command::new(&nodejs)
                     .arg(self.config.src_root.join("src/tools/rustdoc-js/tester.js"))
diff --git a/src/tools/compiletest/src/runtest/mir_opt.rs b/src/tools/compiletest/src/runtest/mir_opt.rs
index d1ec0035744..ded6a68fe58 100644
--- a/src/tools/compiletest/src/runtest/mir_opt.rs
+++ b/src/tools/compiletest/src/runtest/mir_opt.rs
@@ -1,6 +1,6 @@
 use std::fs;
-use std::path::{Path, PathBuf};
 
+use camino::{Utf8Path, Utf8PathBuf};
 use glob::glob;
 use miropt_test_tools::{MiroptTest, MiroptTestFile, files_for_miropt_test};
 use tracing::debug;
@@ -14,7 +14,7 @@ impl TestCx<'_> {
         let should_run = self.should_run(pm);
 
         let mut test_info = files_for_miropt_test(
-            &self.testpaths.file,
+            &self.testpaths.file.as_std_path(),
             self.config.get_pointer_width(),
             self.config.target_cfg().panic.for_miropt_test_tools(),
         );
@@ -38,20 +38,15 @@ impl TestCx<'_> {
 
     fn check_mir_dump(&self, test_info: MiroptTest) {
         let test_dir = self.testpaths.file.parent().unwrap();
-        let test_crate =
-            self.testpaths.file.file_stem().unwrap().to_str().unwrap().replace('-', "_");
+        let test_crate = self.testpaths.file.file_stem().unwrap().replace('-', "_");
 
         let MiroptTest { run_filecheck, suffix, files, passes: _ } = test_info;
 
         if self.config.bless {
-            for e in
-                glob(&format!("{}/{}.*{}.mir", test_dir.display(), test_crate, suffix)).unwrap()
-            {
+            for e in glob(&format!("{}/{}.*{}.mir", test_dir, test_crate, suffix)).unwrap() {
                 fs::remove_file(e.unwrap()).unwrap();
             }
-            for e in
-                glob(&format!("{}/{}.*{}.diff", test_dir.display(), test_crate, suffix)).unwrap()
-            {
+            for e in glob(&format!("{}/{}.*{}.diff", test_dir, test_crate, suffix)).unwrap() {
                 fs::remove_file(e.unwrap()).unwrap();
             }
         }
@@ -60,19 +55,15 @@ impl TestCx<'_> {
             let dumped_string = if let Some(after) = to_file {
                 self.diff_mir_files(from_file.into(), after.into())
             } else {
-                let mut output_file = PathBuf::new();
+                let mut output_file = Utf8PathBuf::new();
                 output_file.push(self.get_mir_dump_dir());
                 output_file.push(&from_file);
-                debug!(
-                    "comparing the contents of: {} with {}",
-                    output_file.display(),
-                    expected_file.display()
-                );
+                debug!("comparing the contents of: {} with {:?}", output_file, expected_file);
                 if !output_file.exists() {
                     panic!(
                         "Output file `{}` from test does not exist, available files are in `{}`",
-                        output_file.display(),
-                        output_file.parent().unwrap().display()
+                        output_file,
+                        output_file.parent().unwrap()
                     );
                 }
                 self.check_mir_test_timestamp(&from_file, &output_file);
@@ -107,21 +98,20 @@ impl TestCx<'_> {
         }
     }
 
-    fn diff_mir_files(&self, before: PathBuf, after: PathBuf) -> String {
-        let to_full_path = |path: PathBuf| {
+    fn diff_mir_files(&self, before: Utf8PathBuf, after: Utf8PathBuf) -> String {
+        let to_full_path = |path: Utf8PathBuf| {
             let full = self.get_mir_dump_dir().join(&path);
             if !full.exists() {
                 panic!(
                     "the mir dump file for {} does not exist (requested in {})",
-                    path.display(),
-                    self.testpaths.file.display(),
+                    path, self.testpaths.file,
                 );
             }
             full
         };
         let before = to_full_path(before);
         let after = to_full_path(after);
-        debug!("comparing the contents of: {} with {}", before.display(), after.display());
+        debug!("comparing the contents of: {} with {}", before, after);
         let before = fs::read_to_string(before).unwrap();
         let after = fs::read_to_string(after).unwrap();
         let before = self.normalize_output(&before, &[]);
@@ -138,8 +128,8 @@ impl TestCx<'_> {
         dumped_string
     }
 
-    fn check_mir_test_timestamp(&self, test_name: &str, output_file: &Path) {
-        let t = |file| fs::metadata(file).unwrap().modified().unwrap();
+    fn check_mir_test_timestamp(&self, test_name: &str, output_file: &Utf8Path) {
+        let t = |file: &Utf8Path| fs::metadata(file.as_std_path()).unwrap().modified().unwrap();
         let source_file = &self.testpaths.file;
         let output_time = t(output_file);
         let source_time = t(source_file);
@@ -147,8 +137,7 @@ impl TestCx<'_> {
             debug!("source file time: {:?} output file time: {:?}", source_time, output_time);
             panic!(
                 "test source file `{}` is newer than potentially stale output file `{}`.",
-                source_file.display(),
-                test_name
+                source_file, test_name
             );
         }
     }
diff --git a/src/tools/compiletest/src/runtest/run_make.rs b/src/tools/compiletest/src/runtest/run_make.rs
index 073116933bd..a5ce929f9b8 100644
--- a/src/tools/compiletest/src/runtest/run_make.rs
+++ b/src/tools/compiletest/src/runtest/run_make.rs
@@ -1,8 +1,8 @@
-use std::path::Path;
 use std::process::{Command, Output, Stdio};
 use std::{env, fs};
 
 use build_helper::fs::{ignore_not_found, recursive_remove};
+use camino::{Utf8Path, Utf8PathBuf};
 
 use super::{ProcRes, TestCx, disable_error_reporting};
 use crate::util::{copy_dir_all, dylib_env_var};
@@ -39,14 +39,16 @@ impl TestCx<'_> {
         // Copy all input files (apart from rmake.rs) to the temporary directory,
         // so that the input directory structure from `tests/run-make/<test>` is mirrored
         // to the `rmake_out` directory.
-        for path in walkdir::WalkDir::new(&self.testpaths.file).min_depth(1) {
-            let path = path.unwrap().path().to_path_buf();
+        for entry in walkdir::WalkDir::new(&self.testpaths.file).min_depth(1) {
+            let entry = entry.unwrap();
+            let path = entry.path();
+            let path = <&Utf8Path>::try_from(path).unwrap();
             if path.file_name().is_some_and(|s| s != "rmake.rs") {
                 let target = rmake_out_dir.join(path.strip_prefix(&self.testpaths.file).unwrap());
                 if path.is_dir() {
-                    copy_dir_all(&path, target).unwrap();
+                    copy_dir_all(&path, &target).unwrap();
                 } else {
-                    fs::copy(&path, target).unwrap();
+                    fs::copy(path.as_std_path(), target).unwrap();
                 }
             }
         }
@@ -83,8 +85,10 @@ impl TestCx<'_> {
         //    on some linux distros.
         // 2. Specific library paths in `self.config.compile_lib_path` needed for running rustc.
 
-        let base_dylib_search_paths =
-            Vec::from_iter(env::split_paths(&env::var(dylib_env_var()).unwrap()));
+        let base_dylib_search_paths = Vec::from_iter(
+            env::split_paths(&env::var(dylib_env_var()).unwrap())
+                .map(|p| Utf8PathBuf::try_from(p).expect("dylib env var contains non-UTF8 paths")),
+        );
 
         // Calculate the paths of the recipe binary. As previously discussed, this is placed at
         // `<base_dir>/<bin_name>` with `bin_name` being `rmake` or `rmake.exe` depending on
@@ -113,13 +117,13 @@ impl TestCx<'_> {
             .arg("-o")
             .arg(&recipe_bin)
             // Specify library search paths for `run_make_support`.
-            .arg(format!("-Ldependency={}", &support_lib_path.parent().unwrap().to_string_lossy()))
-            .arg(format!("-Ldependency={}", &support_lib_deps.to_string_lossy()))
-            .arg(format!("-Ldependency={}", &support_lib_deps_deps.to_string_lossy()))
+            .arg(format!("-Ldependency={}", &support_lib_path.parent().unwrap()))
+            .arg(format!("-Ldependency={}", &support_lib_deps))
+            .arg(format!("-Ldependency={}", &support_lib_deps_deps))
             // Provide `run_make_support` as extern prelude, so test writers don't need to write
             // `extern run_make_support;`.
             .arg("--extern")
-            .arg(format!("run_make_support={}", &support_lib_path.to_string_lossy()))
+            .arg(format!("run_make_support={}", &support_lib_path))
             .arg("--edition=2021")
             .arg(&self.testpaths.file.join("rmake.rs"))
             .arg("-Cprefer-dynamic");
@@ -240,7 +244,7 @@ impl TestCx<'_> {
         if self.config.target.contains("msvc") && !self.config.cc.is_empty() {
             // We need to pass a path to `lib.exe`, so assume that `cc` is `cl.exe`
             // and that `lib.exe` lives next to it.
-            let lib = Path::new(&self.config.cc).parent().unwrap().join("lib.exe");
+            let lib = Utf8Path::new(&self.config.cc).parent().unwrap().join("lib.exe");
 
             // MSYS doesn't like passing flags of the form `/foo` as it thinks it's
             // a path and instead passes `C:\msys64\foo`, so convert all
@@ -262,8 +266,8 @@ impl TestCx<'_> {
 
             cmd.env("IS_MSVC", "1")
                 .env("IS_WINDOWS", "1")
-                .env("MSVC_LIB", format!("'{}' -nologo", lib.display()))
-                .env("MSVC_LIB_PATH", format!("{}", lib.display()))
+                .env("MSVC_LIB", format!("'{}' -nologo", lib))
+                .env("MSVC_LIB_PATH", &lib)
                 // Note: we diverge from legacy run_make and don't lump `CC` the compiler and
                 // default flags together.
                 .env("CC_DEFAULT_FLAGS", &cflags)
diff --git a/src/tools/compiletest/src/runtest/ui.rs b/src/tools/compiletest/src/runtest/ui.rs
index 974e5170465..e87b037cd28 100644
--- a/src/tools/compiletest/src/runtest/ui.rs
+++ b/src/tools/compiletest/src/runtest/ui.rs
@@ -68,7 +68,7 @@ impl TestCx<'_> {
             {
                 let mut coverage_file_path = self.config.build_test_suite_root.clone();
                 coverage_file_path.push("rustfix_missing_coverage.txt");
-                debug!("coverage_file_path: {}", coverage_file_path.display());
+                debug!("coverage_file_path: {}", coverage_file_path);
 
                 let mut file = OpenOptions::new()
                     .create(true)
@@ -76,8 +76,8 @@ impl TestCx<'_> {
                     .open(coverage_file_path.as_path())
                     .expect("could not create or open file");
 
-                if let Err(e) = writeln!(file, "{}", self.testpaths.file.display()) {
-                    panic!("couldn't write to {}: {e:?}", coverage_file_path.display());
+                if let Err(e) = writeln!(file, "{}", self.testpaths.file) {
+                    panic!("couldn't write to {}: {e:?}", coverage_file_path);
                 }
             }
         } else if self.props.run_rustfix {
@@ -119,7 +119,7 @@ impl TestCx<'_> {
                 self.testpaths.relative_dir.join(self.testpaths.file.file_name().unwrap());
             println!(
                 "To only update this specific test, also pass `--test-args {}`",
-                relative_path_to_file.display(),
+                relative_path_to_file,
             );
             self.fatal_proc_rec(
                 &format!("{} errors occurred comparing output.", errors),
@@ -211,8 +211,6 @@ impl TestCx<'_> {
                 let crate_name =
                     self.testpaths.file.file_stem().expect("test must have a file stem");
                 // crate name must be alphanumeric or `_`.
-                let crate_name =
-                    crate_name.to_str().expect("crate name implies file name must be valid UTF-8");
                 // replace `a.foo` -> `a__foo` for crate name purposes.
                 // replace `revision-name-with-dashes` -> `revision_name_with_underscore`
                 let crate_name = crate_name.replace('.', "__");
diff --git a/src/tools/compiletest/src/tests.rs b/src/tools/compiletest/src/tests.rs
index 43c6dc0a67e..e3e4a81755d 100644
--- a/src/tools/compiletest/src/tests.rs
+++ b/src/tools/compiletest/src/tests.rs
@@ -1,5 +1,3 @@
-use std::ffi::OsString;
-
 use crate::debuggers::{extract_gdb_version, extract_lldb_version};
 use crate::is_test;
 
@@ -60,11 +58,11 @@ fn test_extract_lldb_version() {
 
 #[test]
 fn is_test_test() {
-    assert!(is_test(&OsString::from("a_test.rs")));
-    assert!(!is_test(&OsString::from(".a_test.rs")));
-    assert!(!is_test(&OsString::from("a_cat.gif")));
-    assert!(!is_test(&OsString::from("#a_dog_gif")));
-    assert!(!is_test(&OsString::from("~a_temp_file")));
+    assert!(is_test("a_test.rs"));
+    assert!(!is_test(".a_test.rs"));
+    assert!(!is_test("a_cat.gif"));
+    assert!(!is_test("#a_dog_gif"));
+    assert!(!is_test("~a_temp_file"));
 }
 
 #[test]
diff --git a/src/tools/compiletest/src/util.rs b/src/tools/compiletest/src/util.rs
index bff02f1db9f..81f5679aead 100644
--- a/src/tools/compiletest/src/util.rs
+++ b/src/tools/compiletest/src/util.rs
@@ -1,8 +1,7 @@
 use std::env;
-use std::ffi::OsStr;
-use std::path::{Path, PathBuf};
 use std::process::Command;
 
+use camino::{Utf8Path, Utf8PathBuf};
 use tracing::*;
 
 use crate::common::Config;
@@ -34,21 +33,21 @@ pub fn logv(config: &Config, s: String) {
     }
 }
 
-pub trait PathBufExt {
+pub trait Utf8PathBufExt {
     /// Append an extension to the path, even if it already has one.
-    fn with_extra_extension<S: AsRef<OsStr>>(&self, extension: S) -> PathBuf;
+    fn with_extra_extension(&self, extension: &str) -> Utf8PathBuf;
 }
 
-impl PathBufExt for PathBuf {
-    fn with_extra_extension<S: AsRef<OsStr>>(&self, extension: S) -> PathBuf {
-        if extension.as_ref().is_empty() {
+impl Utf8PathBufExt for Utf8PathBuf {
+    fn with_extra_extension(&self, extension: &str) -> Utf8PathBuf {
+        if extension.is_empty() {
             self.clone()
         } else {
-            let mut fname = self.file_name().unwrap().to_os_string();
-            if !extension.as_ref().to_str().unwrap().starts_with('.') {
-                fname.push(".");
+            let mut fname = self.file_name().unwrap().to_string();
+            if !extension.starts_with('.') {
+                fname.push_str(".");
             }
-            fname.push(extension);
+            fname.push_str(extension);
             self.with_file_name(fname)
         }
     }
@@ -71,22 +70,27 @@ pub fn dylib_env_var() -> &'static str {
 
 /// Adds a list of lookup paths to `cmd`'s dynamic library lookup path.
 /// If the dylib_path_var is already set for this cmd, the old value will be overwritten!
-pub fn add_dylib_path(cmd: &mut Command, paths: impl Iterator<Item = impl Into<PathBuf>>) {
+pub fn add_dylib_path(
+    cmd: &mut Command,
+    paths: impl Iterator<Item = impl Into<std::path::PathBuf>>,
+) {
     let path_env = env::var_os(dylib_env_var());
     let old_paths = path_env.as_ref().map(env::split_paths);
     let new_paths = paths.map(Into::into).chain(old_paths.into_iter().flatten());
     cmd.env(dylib_env_var(), env::join_paths(new_paths).unwrap());
 }
 
-pub fn copy_dir_all(src: impl AsRef<Path>, dst: impl AsRef<Path>) -> std::io::Result<()> {
-    std::fs::create_dir_all(&dst)?;
-    for entry in std::fs::read_dir(src)? {
+pub fn copy_dir_all(src: &Utf8Path, dst: &Utf8Path) -> std::io::Result<()> {
+    std::fs::create_dir_all(dst.as_std_path())?;
+    for entry in std::fs::read_dir(src.as_std_path())? {
         let entry = entry?;
+        let path = Utf8PathBuf::try_from(entry.path()).unwrap();
+        let file_name = path.file_name().unwrap();
         let ty = entry.file_type()?;
         if ty.is_dir() {
-            copy_dir_all(entry.path(), dst.as_ref().join(entry.file_name()))?;
+            copy_dir_all(&path, &dst.join(file_name))?;
         } else {
-            std::fs::copy(entry.path(), dst.as_ref().join(entry.file_name()))?;
+            std::fs::copy(path.as_std_path(), dst.join(file_name).as_std_path())?;
         }
     }
     Ok(())
diff --git a/src/tools/compiletest/src/util/tests.rs b/src/tools/compiletest/src/util/tests.rs
index b09a183b14e..5bcae0dcee1 100644
--- a/src/tools/compiletest/src/util/tests.rs
+++ b/src/tools/compiletest/src/util/tests.rs
@@ -3,12 +3,12 @@ use super::*;
 #[test]
 fn path_buf_with_extra_extension_test() {
     assert_eq!(
-        PathBuf::from("foo.rs.stderr"),
-        PathBuf::from("foo.rs").with_extra_extension("stderr")
+        Utf8PathBuf::from("foo.rs.stderr"),
+        Utf8PathBuf::from("foo.rs").with_extra_extension("stderr")
     );
     assert_eq!(
-        PathBuf::from("foo.rs.stderr"),
-        PathBuf::from("foo.rs").with_extra_extension(".stderr")
+        Utf8PathBuf::from("foo.rs.stderr"),
+        Utf8PathBuf::from("foo.rs").with_extra_extension(".stderr")
     );
-    assert_eq!(PathBuf::from("foo.rs"), PathBuf::from("foo.rs").with_extra_extension(""));
+    assert_eq!(Utf8PathBuf::from("foo.rs"), Utf8PathBuf::from("foo.rs").with_extra_extension(""));
 }