Remove various usages of the output function

Author: Kobzol

src/bootstrap/src/core/build_steps/compile.rs

@@ -29,7 +29,7 @@ use crate::core::builder::{Builder, Kind, PathSet, RunConfig, ShouldRun, Step, T
 use crate::core::config::{DebuginfoLevel, LlvmLibunwind, RustcLto, TargetSelection};
 use crate::utils::exec::BootstrapCommand;
 use crate::utils::helpers::{
-    exe, get_clang_cl_resource_dir, is_debug_info, is_dylib, output, symlink_dir, t, up_to_date,
+    exe, get_clang_cl_resource_dir, is_debug_info, is_dylib, symlink_dir, t, up_to_date,
 };
 use crate::LLVM_TOOLS;
 use crate::{CLang, Compiler, DependencyType, GitRepo, Mode};
@@ -1498,10 +1498,10 @@ pub fn compiler_file(
     if builder.config.dry_run() {
         return PathBuf::new();
     }
-    let mut cmd = Command::new(compiler);
+    let mut cmd = BootstrapCommand::new(compiler);
     cmd.args(builder.cflags(target, GitRepo::Rustc, c));
     cmd.arg(format!("-print-file-name={file}"));
-    let out = output(&mut cmd);
+    let out = builder.run(cmd.capture_stdout()).stdout();
     PathBuf::from(out.trim())
 }
 
@@ -1833,7 +1833,9 @@ impl Step for Assemble {
             let llvm::LlvmResult { llvm_config, .. } =
                 builder.ensure(llvm::Llvm { target: target_compiler.host });
             if !builder.config.dry_run() && builder.config.llvm_tools_enabled {
-                let llvm_bin_dir = output(Command::new(llvm_config).arg("--bindir"));
+                let llvm_bin_dir = builder
+                    .run(BootstrapCommand::new(llvm_config).capture_stdout().arg("--bindir"))
+                    .stdout();
                 let llvm_bin_dir = Path::new(llvm_bin_dir.trim());
 
                 // Since we've already built the LLVM tools, install them to the sysroot.
@@ -2158,8 +2160,7 @@ pub fn strip_debug(builder: &Builder<'_>, target: TargetSelection, path: &Path)
     }
 
     let previous_mtime = FileTime::from_last_modification_time(&path.metadata().unwrap());
-    // NOTE: `output` will propagate any errors here.
-    output(Command::new("strip").arg("--strip-debug").arg(path));
+    builder.run(BootstrapCommand::new("strip").capture().arg("--strip-debug").arg(path));
 
     // After running `strip`, we have to set the file modification time to what it was before,
     // otherwise we risk Cargo invalidating its fingerprint and rebuilding the world next time

src/bootstrap/src/core/build_steps/dist.rs

@@ -14,7 +14,6 @@ use std::ffi::OsStr;
 use std::fs;
 use std::io::Write;
 use std::path::{Path, PathBuf};
-use std::process::Command;
 
 use object::read::archive::ArchiveFile;
 use object::BinaryFormat;
@@ -28,7 +27,7 @@ use crate::core::config::TargetSelection;
 use crate::utils::channel::{self, Info};
 use crate::utils::exec::BootstrapCommand;
 use crate::utils::helpers::{
-    exe, is_dylib, move_file, output, t, target_supports_cranelift_backend, timeit,
+    exe, is_dylib, move_file, t, target_supports_cranelift_backend, timeit,
 };
 use crate::utils::tarball::{GeneratedTarball, OverlayKind, Tarball};
 use crate::{Compiler, DependencyType, Mode, LLVM_TOOLS};
@@ -181,9 +180,9 @@ fn make_win_dist(
     }
 
     //Ask gcc where it keeps its stuff
-    let mut cmd = Command::new(builder.cc(target));
+    let mut cmd = BootstrapCommand::new(builder.cc(target));
     cmd.arg("-print-search-dirs");
-    let gcc_out = output(&mut cmd);
+    let gcc_out = builder.run(cmd.capture_stdout()).stdout();
 
     let mut bin_path: Vec<_> = env::split_paths(&env::var_os("PATH").unwrap_or_default()).collect();
     let mut lib_path = Vec::new();
@@ -1024,7 +1023,7 @@ impl Step for PlainSourceTarball {
             }
 
             // Vendor all Cargo dependencies
-            let mut cmd = Command::new(&builder.initial_cargo);
+            let mut cmd = BootstrapCommand::new(&builder.initial_cargo);
             cmd.arg("vendor")
                 .arg("--versioned-dirs")
                 .arg("--sync")
@@ -1062,7 +1061,7 @@ impl Step for PlainSourceTarball {
             }
 
             let config = if !builder.config.dry_run() {
-                t!(String::from_utf8(t!(cmd.output()).stdout))
+                builder.run(cmd.capture()).stdout()
             } else {
                 String::new()
             };
@@ -2079,10 +2078,14 @@ fn maybe_install_llvm(
     } else if let llvm::LlvmBuildStatus::AlreadyBuilt(llvm::LlvmResult { llvm_config, .. }) =
         llvm::prebuilt_llvm_config(builder, target)
     {
-        let mut cmd = Command::new(llvm_config);
+        let mut cmd = BootstrapCommand::new(llvm_config);
         cmd.arg("--libfiles");
         builder.verbose(|| println!("running {cmd:?}"));
-        let files = if builder.config.dry_run() { "".into() } else { output(&mut cmd) };
+        let files = if builder.config.dry_run() {
+            "".into()
+        } else {
+            builder.run(cmd.capture_stdout()).stdout()
+        };
         let build_llvm_out = &builder.llvm_out(builder.config.build);
         let target_llvm_out = &builder.llvm_out(target);
         for file in files.trim_end().split(' ') {

src/bootstrap/src/core/build_steps/format.rs

@@ -1,7 +1,8 @@
 //! Runs rustfmt on the repository.
 
 use crate::core::builder::Builder;
-use crate::utils::helpers::{self, output, program_out_of_date, t};
+use crate::utils::exec::BootstrapCommand;
+use crate::utils::helpers::{self, program_out_of_date, t};
 use build_helper::ci::CiEnv;
 use build_helper::git::get_git_modified_files;
 use ignore::WalkBuilder;
@@ -53,19 +54,17 @@ fn rustfmt(src: &Path, rustfmt: &Path, paths: &[PathBuf], check: bool) -> impl F
 fn get_rustfmt_version(build: &Builder<'_>) -> Option<(String, PathBuf)> {
     let stamp_file = build.out.join("rustfmt.stamp");
 
-    let mut cmd = Command::new(match build.initial_rustfmt() {
+    let mut cmd = BootstrapCommand::new(match build.initial_rustfmt() {
         Some(p) => p,
         None => return None,
     });
     cmd.arg("--version");
-    let output = match cmd.output() {
-        Ok(status) => status,
-        Err(_) => return None,
-    };
-    if !output.status.success() {
+
+    let output = build.run(cmd.capture().allow_failure());
+    if output.is_failure() {
         return None;
     }
-    Some((String::from_utf8(output.stdout).unwrap(), stamp_file))
+    Some((output.stdout(), stamp_file))
 }
 
 /// Return whether the format cache can be reused.
@@ -175,14 +174,16 @@ pub fn format(build: &Builder<'_>, check: bool, all: bool, paths: &[PathBuf]) {
             )
             .is_success();
         if in_working_tree {
-            let untracked_paths_output = output(
-                &mut helpers::git(Some(&build.src))
-                    .arg("status")
-                    .arg("--porcelain")
-                    .arg("-z")
-                    .arg("--untracked-files=normal")
-                    .command,
-            );
+            let untracked_paths_output = build
+                .run(
+                    helpers::git(Some(&build.src))
+                        .capture_stdout()
+                        .arg("status")
+                        .arg("--porcelain")
+                        .arg("-z")
+                        .arg("--untracked-files=normal"),
+                )
+                .stdout();
             let untracked_paths: Vec<_> = untracked_paths_output
                 .split_terminator('\0')
                 .filter_map(

src/bootstrap/src/core/build_steps/llvm.rs

@@ -14,7 +14,6 @@ use std::ffi::{OsStr, OsString};
 use std::fs::{self, File};
 use std::io;
 use std::path::{Path, PathBuf};
-use std::process::Command;
 use std::sync::OnceLock;
 
 use crate::core::builder::{Builder, RunConfig, ShouldRun, Step};
@@ -25,6 +24,7 @@ use crate::utils::helpers::{
 };
 use crate::{generate_smart_stamp_hash, CLang, GitRepo, Kind};
 
+use crate::utils::exec::BootstrapCommand;
 use build_helper::ci::CiEnv;
 use build_helper::git::get_git_merge_base;
 
@@ -478,7 +478,9 @@ impl Step for Llvm {
             let LlvmResult { llvm_config, .. } =
                 builder.ensure(Llvm { target: builder.config.build });
             if !builder.config.dry_run() {
-                let llvm_bindir = output(Command::new(&llvm_config).arg("--bindir"));
+                let llvm_bindir = builder
+                    .run(BootstrapCommand::new(&llvm_config).capture_stdout().arg("--bindir"))
+                    .stdout();
                 let host_bin = Path::new(llvm_bindir.trim());
                 cfg.define(
                     "LLVM_TABLEGEN",
@@ -528,8 +530,8 @@ impl Step for Llvm {
 
         // Helper to find the name of LLVM's shared library on darwin and linux.
         let find_llvm_lib_name = |extension| {
-            let mut cmd = Command::new(&res.llvm_config);
-            let version = output(cmd.arg("--version"));
+            let cmd = BootstrapCommand::new(&res.llvm_config);
+            let version = builder.run(cmd.capture_stdout().arg("--version")).stdout();
             let major = version.split('.').next().unwrap();
 
             match &llvm_version_suffix {
@@ -585,8 +587,8 @@ fn check_llvm_version(builder: &Builder<'_>, llvm_config: &Path) {
         return;
     }
 
-    let mut cmd = Command::new(llvm_config);
-    let version = output(cmd.arg("--version"));
+    let cmd = BootstrapCommand::new(llvm_config);
+    let version = builder.run(cmd.capture_stdout().arg("--version")).stdout();
     let mut parts = version.split('.').take(2).filter_map(|s| s.parse::<u32>().ok());
     if let (Some(major), Some(_minor)) = (parts.next(), parts.next()) {
         if major >= 17 {

src/bootstrap/src/core/build_steps/run.rs

@@ -4,15 +4,14 @@
 //! If it can be reached from `./x.py run` it can go here.
 
 use std::path::PathBuf;
-use std::process::Command;
 
 use crate::core::build_steps::dist::distdir;
 use crate::core::build_steps::test;
 use crate::core::build_steps::tool::{self, SourceType, Tool};
 use crate::core::builder::{Builder, RunConfig, ShouldRun, Step};
 use crate::core::config::flags::get_completion;
 use crate::core::config::TargetSelection;
-use crate::utils::helpers::output;
+use crate::utils::exec::BootstrapCommand;
 use crate::Mode;
 
 #[derive(Debug, PartialOrd, Ord, Clone, Hash, PartialEq, Eq)]
@@ -41,7 +40,8 @@ impl Step for BuildManifest {
             panic!("\n\nfailed to specify `dist.upload-addr` in `config.toml`\n\n")
         });
 
-        let today = output(Command::new("date").arg("+%Y-%m-%d"));
+        let today =
+            builder.run(BootstrapCommand::new("date").capture_stdout().arg("+%Y-%m-%d")).stdout();
 
         cmd.arg(sign);
         cmd.arg(distdir(builder));

src/bootstrap/src/core/build_steps/suggest.rs

@@ -13,24 +13,15 @@ use crate::core::builder::Builder;
 pub fn suggest(builder: &Builder<'_>, run: bool) {
     let git_config = builder.config.git_config();
     let suggestions = builder
-        .tool_cmd(Tool::SuggestTests)
-        .env("SUGGEST_TESTS_GIT_REPOSITORY", git_config.git_repository)
-        .env("SUGGEST_TESTS_NIGHTLY_BRANCH", git_config.nightly_branch)
-        .command
-        .output()
-        .expect("failed to run `suggest-tests` tool");
+        .run(
+            builder
+                .tool_cmd(Tool::SuggestTests)
+                .capture_stdout()
+                .env("SUGGEST_TESTS_GIT_REPOSITORY", git_config.git_repository)
+                .env("SUGGEST_TESTS_NIGHTLY_BRANCH", git_config.nightly_branch),
+        )
+        .stdout();
 
-    if !suggestions.status.success() {
-        println!("failed to run `suggest-tests` tool ({})", suggestions.status);
-        println!(
-            "`suggest_tests` stdout:\n{}`suggest_tests` stderr:\n{}",
-            String::from_utf8(suggestions.stdout).unwrap(),
-            String::from_utf8(suggestions.stderr).unwrap()
-        );
-        panic!("failed to run `suggest-tests`");
-    }
-
-    let suggestions = String::from_utf8(suggestions.stdout).unwrap();
     let suggestions = suggestions
         .lines()
         .map(|line| {

src/bootstrap/src/core/build_steps/synthetic_targets.rs

@@ -9,8 +9,8 @@
 
 use crate::core::builder::{Builder, ShouldRun, Step};
 use crate::core::config::TargetSelection;
+use crate::utils::exec::BootstrapCommand;
 use crate::Compiler;
-use std::process::{Command, Stdio};
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub(crate) struct MirOptPanicAbortSyntheticTarget {
@@ -56,22 +56,16 @@ fn create_synthetic_target(
         return TargetSelection::create_synthetic(&name, path.to_str().unwrap());
     }
 
-    let mut cmd = Command::new(builder.rustc(compiler));
+    let mut cmd = BootstrapCommand::new(builder.rustc(compiler));
     cmd.arg("--target").arg(base.rustc_target_arg());
     cmd.args(["-Zunstable-options", "--print", "target-spec-json"]);
 
     // If `rust.channel` is set to either beta or stable, rustc will complain that
     // we cannot use nightly features. So `RUSTC_BOOTSTRAP` is needed here.
     cmd.env("RUSTC_BOOTSTRAP", "1");
 
-    cmd.stdout(Stdio::piped());
-
-    let output = cmd.spawn().unwrap().wait_with_output().unwrap();
-    if !output.status.success() {
-        panic!("failed to gather the target spec for {base}");
-    }
-
-    let mut spec: serde_json::Value = serde_json::from_slice(&output.stdout).unwrap();
+    let output = builder.run(cmd.capture()).stdout();
+    let mut spec: serde_json::Value = serde_json::from_slice(output.as_bytes()).unwrap();
     let spec_map = spec.as_object_mut().unwrap();
 
     // The `is-builtin` attribute of a spec needs to be removed, otherwise rustc will complain.

src/bootstrap/src/core/build_steps/test.rs

@@ -29,8 +29,7 @@ use crate::core::config::TargetSelection;
 use crate::utils::exec::BootstrapCommand;
 use crate::utils::helpers::{
     self, add_link_lib_path, add_rustdoc_cargo_linker_args, dylib_path, dylib_path_var,
-    linker_args, linker_flags, output, t, target_supports_cranelift_backend, up_to_date,
-    LldThreads,
+    linker_args, linker_flags, t, target_supports_cranelift_backend, up_to_date, LldThreads,
 };
 use crate::utils::render_tests::{add_flags_and_try_run_tests, try_run_tests};
 use crate::{envify, CLang, DocTests, GitRepo, Mode};
@@ -470,19 +469,12 @@ impl Miri {
         // We re-use the `cargo` from above.
         cargo.arg("--print-sysroot");
 
-        // FIXME: Is there a way in which we can re-use the usual `run` helpers?
         if builder.config.dry_run() {
             String::new()
         } else {
             builder.verbose(|| println!("running: {cargo:?}"));
-            let out = cargo
-                .command
-                .output()
-                .expect("We already ran `cargo miri setup` before and that worked");
-            assert!(out.status.success(), "`cargo miri setup` returned with non-0 exit code");
+            let stdout = builder.run(cargo.capture_stdout()).stdout();
             // Output is "<sysroot>\n".
-            let stdout = String::from_utf8(out.stdout)
-                .expect("`cargo miri setup` stdout is not valid UTF-8");
             let sysroot = stdout.trim_end();
             builder.verbose(|| println!("`cargo miri setup --print-sysroot` said: {sysroot:?}"));
             sysroot.to_owned()
@@ -911,25 +903,26 @@ impl Step for RustdocJSNotStd {
     }
 }
 
-fn get_browser_ui_test_version_inner(npm: &Path, global: bool) -> Option<String> {
-    let mut command = Command::new(npm);
+fn get_browser_ui_test_version_inner(
+    builder: &Builder<'_>,
+    npm: &Path,
+    global: bool,
+) -> Option<String> {
+    let mut command = BootstrapCommand::new(npm).capture();
     command.arg("list").arg("--parseable").arg("--long").arg("--depth=0");
     if global {
         command.arg("--global");
     }
-    let lines = command
-        .output()
-        .map(|output| String::from_utf8_lossy(&output.stdout).into_owned())
-        .unwrap_or_default();
+    let lines = builder.run(command.allow_failure()).stdout();
     lines
         .lines()
         .find_map(|l| l.split(':').nth(1)?.strip_prefix("browser-ui-test@"))
         .map(|v| v.to_owned())
 }
 
-fn get_browser_ui_test_version(npm: &Path) -> Option<String> {
-    get_browser_ui_test_version_inner(npm, false)
-        .or_else(|| get_browser_ui_test_version_inner(npm, true))
+fn get_browser_ui_test_version(builder: &Builder<'_>, npm: &Path) -> Option<String> {
+    get_browser_ui_test_version_inner(builder, npm, false)
+        .or_else(|| get_browser_ui_test_version_inner(builder, npm, true))
 }
 
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
@@ -953,7 +946,7 @@ impl Step for RustdocGUI {
                     .config
                     .npm
                     .as_ref()
-                    .map(|p| get_browser_ui_test_version(p).is_some())
+                    .map(|p| get_browser_ui_test_version(builder, p).is_some())
                     .unwrap_or(false)
         }))
     }
@@ -1810,25 +1803,16 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
             cmd.arg("--gdb").arg(gdb);
         }
 
-        let run = |cmd: &mut Command| {
-            cmd.output().map(|output| {
-                String::from_utf8_lossy(&output.stdout)
-                    .lines()
-                    .next()
-                    .unwrap_or_else(|| panic!("{:?} failed {:?}", cmd, output))
-                    .to_string()
-            })
-        };
-
         let lldb_exe = builder.config.lldb.clone().unwrap_or_else(|| PathBuf::from("lldb"));
-        let lldb_version = Command::new(&lldb_exe)
-            .arg("--version")
-            .output()
-            .map(|output| String::from_utf8_lossy(&output.stdout).to_string())
-            .ok();
+        let lldb_version = builder
+            .run(BootstrapCommand::new(&lldb_exe).capture().allow_failure().arg("--version"))
+            .stdout_if_ok();
         if let Some(ref vers) = lldb_version {
             cmd.arg("--lldb-version").arg(vers);
-            let lldb_python_dir = run(Command::new(&lldb_exe).arg("-P")).ok();
+            let lldb_python_dir = builder
+                .run(BootstrapCommand::new(&lldb_exe).allow_failure().capture_stdout().arg("-P"))
+                .stdout_if_ok()
+                .map(|p| p.lines().next().expect("lldb Python dir not found").to_string());
             if let Some(ref dir) = lldb_python_dir {
                 cmd.arg("--lldb-python-dir").arg(dir);
             }
@@ -1884,8 +1868,12 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
             let llvm::LlvmResult { llvm_config, .. } =
                 builder.ensure(llvm::Llvm { target: builder.config.build });
             if !builder.config.dry_run() {
-                let llvm_version = output(Command::new(&llvm_config).arg("--version"));
-                let llvm_components = output(Command::new(&llvm_config).arg("--components"));
+                let llvm_version = builder
+                    .run(BootstrapCommand::new(&llvm_config).capture_stdout().arg("--version"))
+                    .stdout();
+                let llvm_components = builder
+                    .run(BootstrapCommand::new(&llvm_config).capture_stdout().arg("--components"))
+                    .stdout();
                 // Remove trailing newline from llvm-config output.
                 cmd.arg("--llvm-version")
                     .arg(llvm_version.trim())
@@ -1904,7 +1892,9 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
             // separate compilations. We can add LLVM's library path to the
             // platform-specific environment variable as a workaround.
             if !builder.config.dry_run() && suite.ends_with("fulldeps") {
-                let llvm_libdir = output(Command::new(&llvm_config).arg("--libdir"));
+                let llvm_libdir = builder
+                    .run(BootstrapCommand::new(&llvm_config).capture_stdout().arg("--libdir"))
+                    .stdout();
                 add_link_lib_path(vec![llvm_libdir.trim().into()], &mut cmd);
             }
 

src/bootstrap/src/core/build_steps/tool.rs

@@ -1,7 +1,6 @@
 use std::env;
 use std::fs;
 use std::path::{Path, PathBuf};
-use std::process::Command;
 
 use crate::core::build_steps::compile;
 use crate::core::build_steps::toolstate::ToolState;
@@ -10,7 +9,6 @@ use crate::core::builder::{Builder, Cargo as CargoCommand, RunConfig, ShouldRun,
 use crate::core::config::TargetSelection;
 use crate::utils::channel::GitInfo;
 use crate::utils::exec::BootstrapCommand;
-use crate::utils::helpers::output;
 use crate::utils::helpers::{add_dylib_path, exe, t};
 use crate::Compiler;
 use crate::Mode;
@@ -925,7 +923,8 @@ impl Step for LibcxxVersionTool {
             }
         }
 
-        let version_output = output(&mut Command::new(executable));
+        let version_output =
+            builder.run(BootstrapCommand::new(executable).capture_stdout()).stdout();
 
         let version_str = version_output.split_once("version:").unwrap().1;
         let version = version_str.trim().parse::<usize>().unwrap();

src/bootstrap/src/core/builder.rs

@@ -8,7 +8,6 @@ use std::fs;
 use std::hash::Hash;
 use std::ops::Deref;
 use std::path::{Path, PathBuf};
-use std::process::Command;
 use std::time::{Duration, Instant};
 
 use crate::core::build_steps::tool::{self, SourceType};
@@ -20,7 +19,7 @@ use crate::core::config::{DryRun, SplitDebuginfo, TargetSelection};
 use crate::prepare_behaviour_dump_dir;
 use crate::utils::cache::Cache;
 use crate::utils::helpers::{self, add_dylib_path, add_link_lib_path, exe, linker_args};
-use crate::utils::helpers::{check_cfg_arg, libdir, linker_flags, output, t, LldThreads};
+use crate::utils::helpers::{check_cfg_arg, libdir, linker_flags, t, LldThreads};
 use crate::EXTRA_CHECK_CFGS;
 use crate::{Build, CLang, Crate, DocTests, GitRepo, Mode};
 
@@ -1919,7 +1918,9 @@ impl<'a> Builder<'a> {
         // platform-specific environment variable as a workaround.
         if mode == Mode::ToolRustc || mode == Mode::Codegen {
             if let Some(llvm_config) = self.llvm_config(target) {
-                let llvm_libdir = output(Command::new(llvm_config).arg("--libdir"));
+                let llvm_libdir = self
+                    .run(BootstrapCommand::new(llvm_config).capture_stdout().arg("--libdir"))
+                    .stdout();
                 add_link_lib_path(vec![llvm_libdir.trim().into()], &mut cargo);
             }
         }

src/bootstrap/src/core/metadata.rs

@@ -1,9 +1,8 @@
 use std::path::PathBuf;
-use std::process::Command;
 
 use serde_derive::Deserialize;
 
-use crate::utils::helpers::output;
+use crate::utils::exec::BootstrapCommand;
 use crate::{t, Build, Crate};
 
 /// For more information, see the output of
@@ -71,7 +70,7 @@ pub fn build(build: &mut Build) {
 /// particular crate (e.g., `x build sysroot` to build library/sysroot).
 fn workspace_members(build: &Build) -> Vec<Package> {
     let collect_metadata = |manifest_path| {
-        let mut cargo = Command::new(&build.initial_cargo);
+        let mut cargo = BootstrapCommand::new(&build.initial_cargo);
         cargo
             // Will read the libstd Cargo.toml
             // which uses the unstable `public-dependency` feature.
@@ -82,7 +81,8 @@ fn workspace_members(build: &Build) -> Vec<Package> {
             .arg("--no-deps")
             .arg("--manifest-path")
             .arg(build.src.join(manifest_path));
-        let metadata_output = output(&mut cargo);
+        // FIXME: fix stderr
+        let metadata_output = build.run(cargo.capture()).stdout();
         let Output { packages, .. } = t!(serde_json::from_str(&metadata_output));
         packages
     };

src/bootstrap/src/core/sanity.rs

@@ -24,6 +24,7 @@ use std::collections::HashSet;
 
 use crate::builder::Kind;
 use crate::core::config::Target;
+use crate::utils::exec::BootstrapCommand;
 use crate::utils::helpers::output;
 use crate::Build;
 
@@ -352,7 +353,8 @@ than building it.
             // There are three builds of cmake on windows: MSVC, MinGW, and
             // Cygwin. The Cygwin build does not have generators for Visual
             // Studio, so detect that here and error.
-            let out = output(Command::new("cmake").arg("--help"));
+            let out =
+                build.run(BootstrapCommand::new("cmake").capture_stdout().arg("--help")).stdout();
             if !out.contains("Visual Studio") {
                 panic!(
                     "

src/bootstrap/src/lib.rs

@@ -889,14 +889,16 @@ impl Build {
         if let Some(s) = target_config.and_then(|c| c.llvm_filecheck.as_ref()) {
             s.to_path_buf()
         } else if let Some(s) = target_config.and_then(|c| c.llvm_config.as_ref()) {
-            let llvm_bindir = output(Command::new(s).arg("--bindir"));
+            let llvm_bindir =
+                self.run(BootstrapCommand::new(s).capture_stdout().arg("--bindir")).stdout();
             let filecheck = Path::new(llvm_bindir.trim()).join(exe("FileCheck", target));
             if filecheck.exists() {
                 filecheck
             } else {
                 // On Fedora the system LLVM installs FileCheck in the
                 // llvm subdirectory of the libdir.
-                let llvm_libdir = output(Command::new(s).arg("--libdir"));
+                let llvm_libdir =
+                    self.run(BootstrapCommand::new(s).capture_stdout().arg("--libdir")).stdout();
                 let lib_filecheck =
                     Path::new(llvm_libdir.trim()).join("llvm").join(exe("FileCheck", target));
                 if lib_filecheck.exists() {

src/bootstrap/src/utils/cc_detect.rs

@@ -23,11 +23,10 @@
 
 use std::collections::HashSet;
 use std::path::{Path, PathBuf};
-use std::process::Command;
 use std::{env, iter};
 
 use crate::core::config::TargetSelection;
-use crate::utils::helpers::output;
+use crate::utils::exec::BootstrapCommand;
 use crate::{Build, CLang, GitRepo};
 
 // The `cc` crate doesn't provide a way to obtain a path to the detected archiver,
@@ -183,14 +182,15 @@ fn default_compiler(
                 return None;
             }
 
-            let output = output(c.to_command().arg("--version"));
+            let cmd = BootstrapCommand::from(c.to_command());
+            let output = build.run(cmd.capture_stdout().arg("--version")).stdout();
             let i = output.find(" 4.")?;
             match output[i + 3..].chars().next().unwrap() {
                 '0'..='6' => {}
                 _ => return None,
             }
             let alternative = format!("e{gnu_compiler}");
-            if Command::new(&alternative).output().is_ok() {
+            if build.run(BootstrapCommand::new(&alternative).capture()).is_success() {
                 Some(PathBuf::from(alternative))
             } else {
                 None

src/bootstrap/src/utils/exec.rs

@@ -51,11 +51,7 @@ pub struct BootstrapCommand {
 
 impl BootstrapCommand {
     pub fn new<S: AsRef<OsStr>>(program: S) -> Self {
-        Self {
-            command: Command::new(program),
-            failure_behavior: BehaviorOnFailure::Exit,
-            output_mode: OutputMode::Print,
-        }
+        Command::new(program).into()
     }
 
     pub fn arg<S: AsRef<OsStr>>(&mut self, arg: S) -> &mut Self {
@@ -130,6 +126,12 @@ impl AsMut<BootstrapCommand> for BootstrapCommand {
     }
 }
 
+impl From<Command> for BootstrapCommand {
+    fn from(command: Command) -> Self {
+        Self { command, failure_behavior: BehaviorOnFailure::Exit, output_mode: OutputMode::Print }
+    }
+}
+
 /// Represents the output of an executed process.
 #[allow(unused)]
 pub struct CommandOutput(Output);

src/bootstrap/src/utils/helpers.rs

@@ -360,7 +360,7 @@ pub fn get_clang_cl_resource_dir(clang_cl_path: &str) -> PathBuf {
 /// Returns a flag that configures LLD to use only a single thread.
 /// If we use an external LLD, we need to find out which version is it to know which flag should we
 /// pass to it (LLD older than version 10 had a different flag).
-fn lld_flag_no_threads(lld_mode: LldMode, is_windows: bool) -> &'static str {
+fn lld_flag_no_threads(builder: &Builder<'_>, lld_mode: LldMode, is_windows: bool) -> &'static str {
     static LLD_NO_THREADS: OnceLock<(&'static str, &'static str)> = OnceLock::new();
 
     let new_flags = ("/threads:1", "--threads=1");
@@ -369,7 +369,9 @@ fn lld_flag_no_threads(lld_mode: LldMode, is_windows: bool) -> &'static str {
     let (windows_flag, other_flag) = LLD_NO_THREADS.get_or_init(|| {
         let newer_version = match lld_mode {
             LldMode::External => {
-                let out = output(Command::new("lld").arg("-flavor").arg("ld").arg("--version"));
+                let mut cmd = BootstrapCommand::new("lld").capture_stdout();
+                cmd.arg("-flavor").arg("ld").arg("--version");
+                let out = builder.run(cmd).stdout();
                 match (out.find(char::is_numeric), out.find('.')) {
                     (Some(b), Some(e)) => out.as_str()[b..e].parse::<i32>().ok().unwrap_or(14) > 10,
                     _ => true,
@@ -431,7 +433,7 @@ pub fn linker_flags(
         if matches!(lld_threads, LldThreads::No) {
             args.push(format!(
                 "-Clink-arg=-Wl,{}",
-                lld_flag_no_threads(builder.config.lld_mode, target.is_windows())
+                lld_flag_no_threads(builder, builder.config.lld_mode, target.is_windows())
             ));
         }
     }