Move most code from y.rs to build_system/mod.rs

y.rs can't be rustfmt'ed without making it no longer be a valid bash
script.

build_system/build_backend.rs

@@ -49,7 +49,7 @@ pub(crate) fn build_backend(
     cmd.env("RUSTFLAGS", rustflags);
 
     eprintln!("[BUILD] rustc_codegen_cranelift");
-    crate::utils::spawn_and_wait(cmd);
+    super::utils::spawn_and_wait(cmd);
 
     Path::new("target").join(host_triple).join(channel)
 }

build_system/build_sysroot.rs

@@ -3,9 +3,9 @@ use std::fs;
 use std::path::{Path, PathBuf};
 use std::process::{self, Command};
 
-use crate::rustc_info::{get_file_name, get_rustc_version};
-use crate::utils::{spawn_and_wait, try_hard_link};
-use crate::SysrootKind;
+use super::rustc_info::{get_file_name, get_rustc_version};
+use super::utils::{spawn_and_wait, try_hard_link};
+use super::SysrootKind;
 
 pub(crate) fn build_sysroot(
     channel: &str,
@@ -52,7 +52,7 @@ pub(crate) fn build_sysroot(
         .arg("-g");
     spawn_and_wait(build_cargo_wrapper_cmd);
 
-    let default_sysroot = crate::rustc_info::get_default_sysroot();
+    let default_sysroot = super::rustc_info::get_default_sysroot();
 
     let rustlib = target_dir.join("lib").join("rustlib");
     let host_rustlib_lib = rustlib.join(host_triple).join("lib");
@@ -167,7 +167,7 @@ fn build_clif_sysroot_for_triple(
 
     let build_dir = Path::new("build_sysroot").join("target").join(triple).join(channel);
 
-    if !crate::config::get_bool("keep_sysroot") {
+    if !super::config::get_bool("keep_sysroot") {
         // Cleanup the target dir with the exception of build scripts and the incremental cache
         for dir in ["build", "deps", "examples", "native"] {
             if build_dir.join(dir).exists() {

build_system/mod.rs

@@ -0,0 +1,127 @@
+use std::env;
+use std::path::PathBuf;
+use std::process;
+
+mod build_backend;
+mod build_sysroot;
+mod config;
+mod prepare;
+mod rustc_info;
+mod utils;
+
+fn usage() {
+    eprintln!("Usage:");
+    eprintln!("  ./y.rs prepare");
+    eprintln!(
+        "  ./y.rs build [--debug] [--sysroot none|clif|llvm] [--target-dir DIR] [--no-unstable-features]"
+    );
+}
+
+macro_rules! arg_error {
+    ($($err:tt)*) => {{
+        eprintln!($($err)*);
+        usage();
+        std::process::exit(1);
+    }};
+}
+
+enum Command {
+    Build,
+}
+
+#[derive(Copy, Clone)]
+pub(crate) enum SysrootKind {
+    None,
+    Clif,
+    Llvm,
+}
+
+pub fn main() {
+    env::set_var("CG_CLIF_DISPLAY_CG_TIME", "1");
+    env::set_var("CG_CLIF_DISABLE_INCR_CACHE", "1");
+    // The target dir is expected in the default location. Guard against the user changing it.
+    env::set_var("CARGO_TARGET_DIR", "target");
+
+    let mut args = env::args().skip(1);
+    let command = match args.next().as_deref() {
+        Some("prepare") => {
+            if args.next().is_some() {
+                arg_error!("./x.rs prepare doesn't expect arguments");
+            }
+            prepare::prepare();
+            process::exit(0);
+        }
+        Some("build") => Command::Build,
+        Some(flag) if flag.starts_with('-') => arg_error!("Expected command found flag {}", flag),
+        Some(command) => arg_error!("Unknown command {}", command),
+        None => {
+            usage();
+            process::exit(0);
+        }
+    };
+
+    let mut target_dir = PathBuf::from("build");
+    let mut channel = "release";
+    let mut sysroot_kind = SysrootKind::Clif;
+    let mut use_unstable_features = true;
+    while let Some(arg) = args.next().as_deref() {
+        match arg {
+            "--target-dir" => {
+                target_dir = PathBuf::from(args.next().unwrap_or_else(|| {
+                    arg_error!("--target-dir requires argument");
+                }))
+            }
+            "--debug" => channel = "debug",
+            "--sysroot" => {
+                sysroot_kind = match args.next().as_deref() {
+                    Some("none") => SysrootKind::None,
+                    Some("clif") => SysrootKind::Clif,
+                    Some("llvm") => SysrootKind::Llvm,
+                    Some(arg) => arg_error!("Unknown sysroot kind {}", arg),
+                    None => arg_error!("--sysroot requires argument"),
+                }
+            }
+            "--no-unstable-features" => use_unstable_features = false,
+            flag if flag.starts_with("-") => arg_error!("Unknown flag {}", flag),
+            arg => arg_error!("Unexpected argument {}", arg),
+        }
+    }
+
+    let host_triple = if let Ok(host_triple) = std::env::var("HOST_TRIPLE") {
+        host_triple
+    } else if let Some(host_triple) = config::get_value("host") {
+        host_triple
+    } else {
+        rustc_info::get_host_triple()
+    };
+    let target_triple = if let Ok(target_triple) = std::env::var("TARGET_TRIPLE") {
+        if target_triple != "" {
+            target_triple
+        } else {
+            host_triple.clone() // Empty target triple can happen on GHA
+        }
+    } else if let Some(target_triple) = config::get_value("target") {
+        target_triple
+    } else {
+        host_triple.clone()
+    };
+
+    if target_triple.ends_with("-msvc") {
+        eprintln!("The MSVC toolchain is not yet supported by rustc_codegen_cranelift.");
+        eprintln!("Switch to the MinGW toolchain for Windows support.");
+        eprintln!("Hint: You can use `rustup set default-host x86_64-pc-windows-gnu` to");
+        eprintln!("set the global default target to MinGW");
+        process::exit(1);
+    }
+
+    let cg_clif_build_dir =
+        build_backend::build_backend(channel, &host_triple, use_unstable_features);
+    build_sysroot::build_sysroot(
+        channel,
+        sysroot_kind,
+        &target_dir,
+        cg_clif_build_dir,
+        &host_triple,
+        &target_triple,
+    );
+}

build_system/prepare.rs

@@ -5,8 +5,8 @@ use std::fs;
 use std::path::Path;
 use std::process::Command;
 
-use crate::rustc_info::{get_file_name, get_rustc_path, get_rustc_version};
-use crate::utils::{copy_dir_recursively, spawn_and_wait};
+use super::rustc_info::{get_file_name, get_rustc_path, get_rustc_version};
+use super::utils::{copy_dir_recursively, spawn_and_wait};
 
 pub(crate) fn prepare() {
     prepare_sysroot();

y.rs

@@ -23,136 +23,9 @@ exec ${0/.rs/.bin} $@
 //!
 //! The name `y.rs` was chosen to not conflict with rustc's `x.py`.
 
-use std::env;
-use std::path::PathBuf;
-use std::process;
-
-#[path = "build_system/build_backend.rs"]
-mod build_backend;
-#[path = "build_system/build_sysroot.rs"]
-mod build_sysroot;
-#[path = "build_system/config.rs"]
-mod config;
-#[path = "build_system/prepare.rs"]
-mod prepare;
-#[path = "build_system/rustc_info.rs"]
-mod rustc_info;
-#[path = "build_system/utils.rs"]
-mod utils;
-
-fn usage() {
-    eprintln!("Usage:");
-    eprintln!("  ./y.rs prepare");
-    eprintln!(
-        "  ./y.rs build [--debug] [--sysroot none|clif|llvm] [--target-dir DIR] [--no-unstable-features]"
-    );
-}
-
-macro_rules! arg_error {
-    ($($err:tt)*) => {{
-        eprintln!($($err)*);
-        usage();
-        std::process::exit(1);
-    }};
-}
-
-enum Command {
-    Build,
-}
-
-#[derive(Copy, Clone)]
-enum SysrootKind {
-    None,
-    Clif,
-    Llvm,
-}
+#[path = "build_system/mod.rs"]
+mod build_system;
 
 fn main() {
-    env::set_var("CG_CLIF_DISPLAY_CG_TIME", "1");
-    env::set_var("CG_CLIF_DISABLE_INCR_CACHE", "1");
-    // The target dir is expected in the default location. Guard against the user changing it.
-    env::set_var("CARGO_TARGET_DIR", "target");
-
-    let mut args = env::args().skip(1);
-    let command = match args.next().as_deref() {
-        Some("prepare") => {
-            if args.next().is_some() {
-                arg_error!("./x.rs prepare doesn't expect arguments");
-            }
-            prepare::prepare();
-            process::exit(0);
-        }
-        Some("build") => Command::Build,
-        Some(flag) if flag.starts_with('-') => arg_error!("Expected command found flag {}", flag),
-        Some(command) => arg_error!("Unknown command {}", command),
-        None => {
-            usage();
-            process::exit(0);
-        }
-    };
-
-    let mut target_dir = PathBuf::from("build");
-    let mut channel = "release";
-    let mut sysroot_kind = SysrootKind::Clif;
-    let mut use_unstable_features = true;
-    while let Some(arg) = args.next().as_deref() {
-        match arg {
-            "--target-dir" => {
-                target_dir = PathBuf::from(args.next().unwrap_or_else(|| {
-                    arg_error!("--target-dir requires argument");
-                }))
-            }
-            "--debug" => channel = "debug",
-            "--sysroot" => {
-                sysroot_kind = match args.next().as_deref() {
-                    Some("none") => SysrootKind::None,
-                    Some("clif") => SysrootKind::Clif,
-                    Some("llvm") => SysrootKind::Llvm,
-                    Some(arg) => arg_error!("Unknown sysroot kind {}", arg),
-                    None => arg_error!("--sysroot requires argument"),
-                }
-            }
-            "--no-unstable-features" => use_unstable_features = false,
-            flag if flag.starts_with("-") => arg_error!("Unknown flag {}", flag),
-            arg => arg_error!("Unexpected argument {}", arg),
-        }
-    }
-
-    let host_triple = if let Ok(host_triple) = std::env::var("HOST_TRIPLE") {
-        host_triple
-    } else if let Some(host_triple) = crate::config::get_value("host") {
-        host_triple
-    } else {
-        rustc_info::get_host_triple()
-    };
-    let target_triple = if let Ok(target_triple) = std::env::var("TARGET_TRIPLE") {
-        if target_triple != "" {
-            target_triple
-        } else {
-            host_triple.clone() // Empty target triple can happen on GHA
-        }
-    } else if let Some(target_triple) = crate::config::get_value("target") {
-        target_triple
-    } else {
-        host_triple.clone()
-    };
-
-    if target_triple.ends_with("-msvc") {
-        eprintln!("The MSVC toolchain is not yet supported by rustc_codegen_cranelift.");
-        eprintln!("Switch to the MinGW toolchain for Windows support.");
-        eprintln!("Hint: You can use `rustup set default-host x86_64-pc-windows-gnu` to");
-        eprintln!("set the global default target to MinGW");
-        process::exit(1);
-    }
-
-    let cg_clif_build_dir =
-        build_backend::build_backend(channel, &host_triple, use_unstable_features);
-    build_sysroot::build_sysroot(
-        channel,
-        sysroot_kind,
-        &target_dir,
-        cg_clif_build_dir,
-        &host_triple,
-        &target_triple,
-    );
+    build_system::main();
 }