Rollup merge of #137373 - Kobzol:tool-stage0-improve, r=jieyouxu

Compile run-make-support and run-make tests with the bootstrap compiler

It does not seem necessary to have to recompile run-make-support on changes to the local compiler/stdlib. This PR simplifies the implementation of a few tools, then switches rms to stage0 and also makes the handling of environment variables in run-make tests simpler.

Best reviewed commit-by-commit. I can split it into multiple PRs if you want.

Also tested that `COMPILETEST_FORCE_STAGE0=1 ./x test tests/run-make --stage 0` still works. Incredibly, it looks like it even passes more tests than on `master` :laughing:

r? ``@jieyouxu``

8 files changed, 69 insertions, 119 deletions

diff --git a/src/tools/compiletest/src/common.rs b/src/tools/compiletest/src/common.rs
index b302c6a49f5..978836cb663 100644
--- a/src/tools/compiletest/src/common.rs
+++ b/src/tools/compiletest/src/common.rs
@@ -190,6 +190,9 @@ pub struct Config {
     /// The cargo executable.
     pub cargo_path: Option<PathBuf>,
 
+    /// Rustc executable used to compile run-make recipes.
+    pub stage0_rustc_path: Option<PathBuf>,
+
     /// The rustdoc executable.
     pub rustdoc_path: Option<PathBuf>,
 
diff --git a/src/tools/compiletest/src/lib.rs b/src/tools/compiletest/src/lib.rs
index 9dff7047bc4..e93f32c86bc 100644
--- a/src/tools/compiletest/src/lib.rs
+++ b/src/tools/compiletest/src/lib.rs
@@ -54,6 +54,12 @@ pub fn parse_config(args: Vec<String>) -> Config {
         .reqopt("", "run-lib-path", "path to target shared libraries", "PATH")
         .reqopt("", "rustc-path", "path to rustc to use for compiling", "PATH")
         .optopt("", "cargo-path", "path to cargo to use for compiling", "PATH")
+        .optopt(
+            "",
+            "stage0-rustc-path",
+            "path to rustc to use for compiling run-make recipes",
+            "PATH",
+        )
         .optopt("", "rustdoc-path", "path to rustdoc to use for compiling", "PATH")
         .optopt("", "coverage-dump-path", "path to coverage-dump to use in tests", "PATH")
         .reqopt("", "python", "path to python to use for doc tests", "PATH")
@@ -320,6 +326,7 @@ pub fn parse_config(args: Vec<String>) -> Config {
         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),
         python: matches.opt_str("python").unwrap(),
diff --git a/src/tools/compiletest/src/runtest/run_make.rs b/src/tools/compiletest/src/runtest/run_make.rs
index 9bb3993223e..07f4d7c4942 100644
--- a/src/tools/compiletest/src/runtest/run_make.rs
+++ b/src/tools/compiletest/src/runtest/run_make.rs
@@ -173,7 +173,8 @@ impl TestCx<'_> {
     fn run_rmake_v2_test(&self) {
         // For `run-make` V2, we need to perform 2 steps to build and run a `run-make` V2 recipe
         // (`rmake.rs`) to run the actual tests. The support library is already built as a tool rust
-        // library and is available under `build/$TARGET/stageN-tools-bin/librun_make_support.rlib`.
+        // library and is available under
+        // `build/$HOST/stage0-bootstrap-tools/$TARGET/release/librun_make_support.rlib`.
         //
         // 1. We need to build the recipe `rmake.rs` as a binary and link in the `run_make_support`
         //    library.
@@ -224,25 +225,21 @@ impl TestCx<'_> {
         //
         // ```
         // build/<target_triple>/
-        // ├── stageN-tools-bin/
-        // │   └── librun_make_support.rlib       // <- support rlib itself
-        // ├── stageN-tools/
-        // │   ├── release/deps/                  // <- deps of deps
-        // │   └── <host_triple>/release/deps/    // <- deps
+        // ├── stage0-bootstrap-tools/
+        // │   ├── <host_triple>/release/librun_make_support.rlib   // <- support rlib itself
+        // │   ├── <host_triple>/release/deps/                      // <- deps
+        // │   └── release/deps/                                    // <- deps of deps
         // ```
         //
         // FIXME(jieyouxu): there almost certainly is a better way to do this (specifically how the
-        // support lib and its deps are organized, can't we copy them to the tools-bin dir as
-        // well?), but this seems to work for now.
+        // support lib and its deps are organized), but this seems to work for now.
 
-        let stage_number = self.config.stage;
+        let tools_bin = host_build_root.join("stage0-bootstrap-tools");
+        let support_host_path = tools_bin.join(&self.config.host).join("release");
+        let support_lib_path = support_host_path.join("librun_make_support.rlib");
 
-        let stage_tools_bin = host_build_root.join(format!("stage{stage_number}-tools-bin"));
-        let support_lib_path = stage_tools_bin.join("librun_make_support.rlib");
-
-        let stage_tools = host_build_root.join(format!("stage{stage_number}-tools"));
-        let support_lib_deps = stage_tools.join(&self.config.host).join("release").join("deps");
-        let support_lib_deps_deps = stage_tools.join("release").join("deps");
+        let support_lib_deps = support_host_path.join("deps");
+        let support_lib_deps_deps = tools_bin.join("release").join("deps");
 
         // To compile the recipe with rustc, we need to provide suitable dynamic library search
         // paths to rustc. This includes both:
@@ -253,12 +250,6 @@ impl TestCx<'_> {
         let base_dylib_search_paths =
             Vec::from_iter(env::split_paths(&env::var(dylib_env_var()).unwrap()));
 
-        let host_dylib_search_paths = {
-            let mut paths = vec![self.config.compile_lib_path.clone()];
-            paths.extend(base_dylib_search_paths.iter().cloned());
-            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
         // platform.
@@ -268,7 +259,15 @@ impl TestCx<'_> {
             p
         };
 
-        let mut rustc = Command::new(&self.config.rustc_path);
+        // run-make-support and run-make tests are compiled using the stage0 compiler
+        // If the stage is 0, then the compiler that we test (either bootstrap or an explicitly
+        // set compiler) is the one that actually compiled run-make-support.
+        let stage0_rustc = self
+            .config
+            .stage0_rustc_path
+            .as_ref()
+            .expect("stage0 rustc is required to run run-make tests");
+        let mut rustc = Command::new(&stage0_rustc);
         rustc
             .arg("-o")
             .arg(&recipe_bin)
@@ -282,35 +281,12 @@ impl TestCx<'_> {
             .arg(format!("run_make_support={}", &support_lib_path.to_string_lossy()))
             .arg("--edition=2021")
             .arg(&self.testpaths.file.join("rmake.rs"))
-            .arg("-Cprefer-dynamic")
-            // Provide necessary library search paths for rustc.
-            .env(dylib_env_var(), &env::join_paths(host_dylib_search_paths).unwrap());
+            .arg("-Cprefer-dynamic");
 
         // In test code we want to be very pedantic about values being silently discarded that are
         // annotated with `#[must_use]`.
         rustc.arg("-Dunused_must_use");
 
-        // > `cg_clif` uses `COMPILETEST_FORCE_STAGE0=1 ./x.py test --stage 0` for running the rustc
-        // > test suite. With the introduction of rmake.rs this broke. `librun_make_support.rlib` is
-        // > compiled using the bootstrap rustc wrapper which sets `--sysroot
-        // > build/aarch64-unknown-linux-gnu/stage0-sysroot`, but then compiletest will compile
-        // > `rmake.rs` using the sysroot of the bootstrap compiler causing it to not find the
-        // > `libstd.rlib` against which `librun_make_support.rlib` is compiled.
-        //
-        // The gist here is that we have to pass the proper stage0 sysroot if we want
-        //
-        // ```
-        // $ COMPILETEST_FORCE_STAGE0=1 ./x test run-make --stage 0
-        // ```
-        //
-        // to work correctly.
-        //
-        // See <https://github.com/rust-lang/rust/pull/122248> for more background.
-        let stage0_sysroot = host_build_root.join("stage0-sysroot");
-        if std::env::var_os("COMPILETEST_FORCE_STAGE0").is_some() {
-            rustc.arg("--sysroot").arg(&stage0_sysroot);
-        }
-
         // Now run rustc to build the recipe.
         let res = self.run_command_to_procres(&mut rustc);
         if !res.status.success() {
@@ -320,35 +296,24 @@ impl TestCx<'_> {
         // To actually run the recipe, we have to provide the recipe with a bunch of information
         // provided through env vars.
 
-        // Compute stage-specific standard library paths.
-        let stage_std_path = host_build_root.join(format!("stage{stage_number}")).join("lib");
-
         // Compute dynamic library search paths for recipes.
+        // These dylib directories are needed to **execute the recipe**.
         let recipe_dylib_search_paths = {
             let mut paths = base_dylib_search_paths.clone();
-
-            // For stage 0, we need to explicitly include the stage0-sysroot libstd dylib.
-            // See <https://github.com/rust-lang/rust/issues/135373>.
-            if std::env::var_os("COMPILETEST_FORCE_STAGE0").is_some() {
-                paths.push(
-                    stage0_sysroot.join("lib").join("rustlib").join(&self.config.host).join("lib"),
-                );
-            }
-
-            paths.push(support_lib_path.parent().unwrap().to_path_buf());
-            paths.push(stage_std_path.join("rustlib").join(&self.config.host).join("lib"));
-            paths
-        };
-
-        // Compute runtime library search paths for recipes. This is target-specific.
-        let target_runtime_dylib_search_paths = {
-            let mut paths = vec![rmake_out_dir.clone()];
-            paths.extend(base_dylib_search_paths.iter().cloned());
+            paths.push(
+                stage0_rustc
+                    .parent()
+                    .unwrap()
+                    .parent()
+                    .unwrap()
+                    .join("lib")
+                    .join("rustlib")
+                    .join(&self.config.host)
+                    .join("lib"),
+            );
             paths
         };
 
-        // FIXME(jieyouxu): please rename `TARGET_RPATH_ENV`, `HOST_RPATH_DIR` and
-        // `TARGET_RPATH_DIR`, it is **extremely** confusing!
         let mut cmd = Command::new(&recipe_bin);
         cmd.current_dir(&rmake_out_dir)
             .stdout(Stdio::piped())
@@ -357,9 +322,14 @@ impl TestCx<'_> {
             // example, this could be `LD_LIBRARY_PATH` on some linux distros but `PATH` on Windows.
             .env("LD_LIB_PATH_ENVVAR", dylib_env_var())
             // Provide the dylib search paths.
+            // This is required to run the **recipe** itself.
             .env(dylib_env_var(), &env::join_paths(recipe_dylib_search_paths).unwrap())
-            // Provide runtime dylib search paths.
-            .env("TARGET_RPATH_ENV", &env::join_paths(target_runtime_dylib_search_paths).unwrap())
+            // Provide the directory to libraries that are needed to run the *compiler* invoked
+            // by the recipe.
+            .env("HOST_RUSTC_DYLIB_PATH", &self.config.compile_lib_path)
+            // Provide the directory to libraries that might be needed to run binaries created
+            // by a compiler invoked by the recipe.
+            .env("TARGET_EXE_DYLIB_PATH", &self.config.run_lib_path)
             // Provide the target.
             .env("TARGET", &self.config.target)
             // Some tests unfortunately still need Python, so provide path to a Python interpreter.
@@ -370,13 +340,6 @@ impl TestCx<'_> {
             .env("BUILD_ROOT", &host_build_root)
             // Provide path to stage-corresponding rustc.
             .env("RUSTC", &self.config.rustc_path)
-            // Provide the directory to libraries that are needed to run the *compiler*. This is not
-            // to be confused with `TARGET_RPATH_ENV` or `TARGET_RPATH_DIR`. This is needed if the
-            // recipe wants to invoke rustc.
-            .env("HOST_RPATH_DIR", &self.config.compile_lib_path)
-            // Provide the directory to libraries that might be needed to run compiled binaries
-            // (further compiled by the recipe!).
-            .env("TARGET_RPATH_DIR", &self.config.run_lib_path)
             // Provide which LLVM components are available (e.g. which LLVM components are provided
             // through a specific CI runner).
             .env("LLVM_COMPONENTS", &self.config.llvm_components);
diff --git a/src/tools/run-make-support/src/external_deps/rustc.rs b/src/tools/run-make-support/src/external_deps/rustc.rs
index 710ba025830..cb2bd83815a 100644
--- a/src/tools/run-make-support/src/external_deps/rustc.rs
+++ b/src/tools/run-make-support/src/external_deps/rustc.rs
@@ -5,7 +5,7 @@ use std::str::FromStr as _;
 use crate::command::Command;
 use crate::env::env_var;
 use crate::path_helpers::cwd;
-use crate::util::set_host_rpath;
+use crate::util::set_host_compiler_dylib_path;
 use crate::{is_aix, is_darwin, is_msvc, is_windows, uname};
 
 /// Construct a new `rustc` invocation. This will automatically set the library
@@ -15,8 +15,8 @@ pub fn rustc() -> Rustc {
     Rustc::new()
 }
 
-/// Construct a plain `rustc` invocation with no flags set. Note that [`set_host_rpath`]
-/// still presets the environment variable `HOST_RPATH_DIR` by default.
+/// Construct a plain `rustc` invocation with no flags set. Note that [`set_host_compiler_dylib_path`]
+/// still presets the environment variable `HOST_RUSTC_DYLIB_PATH` by default.
 #[track_caller]
 pub fn bare_rustc() -> Rustc {
     Rustc::bare()
@@ -44,7 +44,7 @@ pub fn rustc_path() -> String {
 #[track_caller]
 fn setup_common() -> Command {
     let mut cmd = Command::new(rustc_path());
-    set_host_rpath(&mut cmd);
+    set_host_compiler_dylib_path(&mut cmd);
     cmd
 }
 
diff --git a/src/tools/run-make-support/src/external_deps/rustdoc.rs b/src/tools/run-make-support/src/external_deps/rustdoc.rs
index 8a659cd3d8a..433a57cd9fa 100644
--- a/src/tools/run-make-support/src/external_deps/rustdoc.rs
+++ b/src/tools/run-make-support/src/external_deps/rustdoc.rs
@@ -2,16 +2,10 @@ use std::ffi::OsStr;
 use std::path::Path;
 
 use crate::command::Command;
-use crate::env::{env_var, env_var_os};
-use crate::util::set_host_rpath;
+use crate::env::env_var;
+use crate::util::set_host_compiler_dylib_path;
 
-/// Construct a plain `rustdoc` invocation with no flags set.
-#[track_caller]
-pub fn bare_rustdoc() -> Rustdoc {
-    Rustdoc::bare()
-}
-
-/// Construct a new `rustdoc` invocation with `-L $(TARGET_RPATH_DIR)` set.
+/// Construct a new `rustdoc` invocation.
 #[track_caller]
 pub fn rustdoc() -> Rustdoc {
     Rustdoc::new()
@@ -29,23 +23,15 @@ crate::macros::impl_common_helpers!(Rustdoc);
 fn setup_common() -> Command {
     let rustdoc = env_var("RUSTDOC");
     let mut cmd = Command::new(rustdoc);
-    set_host_rpath(&mut cmd);
+    set_host_compiler_dylib_path(&mut cmd);
     cmd
 }
 
 impl Rustdoc {
     /// Construct a bare `rustdoc` invocation.
     #[track_caller]
-    pub fn bare() -> Self {
-        let cmd = setup_common();
-        Self { cmd }
-    }
-
-    /// Construct a `rustdoc` invocation with `-L $(TARGET_RPATH_DIR)` set.
-    #[track_caller]
     pub fn new() -> Self {
-        let mut cmd = setup_common();
-        cmd.arg("-L").arg(env_var_os("TARGET_RPATH_DIR"));
+        let cmd = setup_common();
         Self { cmd }
     }
 
diff --git a/src/tools/run-make-support/src/lib.rs b/src/tools/run-make-support/src/lib.rs
index 7e63ab3159a..d40ec9c4116 100644
--- a/src/tools/run-make-support/src/lib.rs
+++ b/src/tools/run-make-support/src/lib.rs
@@ -67,7 +67,7 @@ pub use llvm::{
 };
 pub use python::python_command;
 pub use rustc::{aux_build, bare_rustc, rustc, rustc_path, Rustc};
-pub use rustdoc::{bare_rustdoc, rustdoc, Rustdoc};
+pub use rustdoc::{rustdoc, Rustdoc};
 
 /// [`diff`][mod@diff] is implemented in terms of the [similar] library.
 ///
diff --git a/src/tools/run-make-support/src/run.rs b/src/tools/run-make-support/src/run.rs
index 3eeba6fd526..7812863ccc2 100644
--- a/src/tools/run-make-support/src/run.rs
+++ b/src/tools/run-make-support/src/run.rs
@@ -1,10 +1,10 @@
 use std::ffi::OsStr;
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 use std::{env, panic};
 
 use crate::command::{Command, CompletedProcess};
-use crate::util::{handle_failed_output, set_host_rpath};
-use crate::{cwd, env_var, is_windows};
+use crate::util::handle_failed_output;
+use crate::{cwd, env_var};
 
 #[track_caller]
 fn run_common(name: &str, args: Option<&[&str]>) -> Command {
@@ -18,10 +18,11 @@ fn run_common(name: &str, args: Option<&[&str]>) -> Command {
             cmd.arg(arg);
         }
     }
+
     cmd.env(&ld_lib_path_envvar, {
         let mut paths = vec![];
         paths.push(cwd());
-        for p in env::split_paths(&env_var("TARGET_RPATH_ENV")) {
+        for p in env::split_paths(&env_var("TARGET_EXE_DYLIB_PATH")) {
             paths.push(p.to_path_buf());
         }
         for p in env::split_paths(&env_var(&ld_lib_path_envvar)) {
@@ -31,15 +32,6 @@ fn run_common(name: &str, args: Option<&[&str]>) -> Command {
     });
     cmd.env("LC_ALL", "C"); // force english locale
 
-    if is_windows() {
-        let mut paths = vec![];
-        for p in env::split_paths(&std::env::var("PATH").unwrap_or(String::new())) {
-            paths.push(p.to_path_buf());
-        }
-        paths.push(Path::new(&env_var("TARGET_RPATH_DIR")).to_path_buf());
-        cmd.env("PATH", env::join_paths(paths.iter()).unwrap());
-    }
-
     cmd
 }
 
@@ -84,7 +76,6 @@ pub fn run_fail(name: &str) -> CompletedProcess {
 #[track_caller]
 pub fn cmd<S: AsRef<OsStr>>(program: S) -> Command {
     let mut command = Command::new(program);
-    set_host_rpath(&mut command);
     command.env("LC_ALL", "C"); // force english locale
     command
 }
diff --git a/src/tools/run-make-support/src/util.rs b/src/tools/run-make-support/src/util.rs
index 703e3ad1c6c..af01758447b 100644
--- a/src/tools/run-make-support/src/util.rs
+++ b/src/tools/run-make-support/src/util.rs
@@ -24,13 +24,13 @@ pub(crate) fn handle_failed_output(
     std::process::exit(1)
 }
 
-/// Set the runtime library path as needed for running the host rustc/rustdoc/etc.
-pub(crate) fn set_host_rpath(cmd: &mut Command) {
+/// Set the runtime library paths as needed for running the host compilers (rustc/rustdoc/etc).
+pub(crate) fn set_host_compiler_dylib_path(cmd: &mut Command) {
     let ld_lib_path_envvar = env_var("LD_LIB_PATH_ENVVAR");
     cmd.env(&ld_lib_path_envvar, {
         let mut paths = vec![];
         paths.push(cwd());
-        paths.push(PathBuf::from(env_var("HOST_RPATH_DIR")));
+        paths.push(PathBuf::from(env_var("HOST_RUSTC_DYLIB_PATH")));
         for p in std::env::split_paths(&env_var(&ld_lib_path_envvar)) {
             paths.push(p.to_path_buf());
         }