Move download-rustc from bootstrap.py to rustbuild

- Remove download-rustc handling from bootstrap.py
- Allow a custom `pattern` in `builder.unpack()`
- Only download rustc once another part of bootstrap depends on it.

  This is somewhat necessary since the download functions rely on having a full
  `Builder`, which isn't available until after config parsing finishes.

Author: jyn514

src/bootstrap/bootstrap.py

@@ -446,7 +446,7 @@ def __init__(self):
         self.nix_deps_dir = None
         self.rustc_commit = None
 
-    def download_toolchain(self, stage0=True, rustc_channel=None):
+    def download_toolchain(self, rustc_channel=None):
         """Fetch the build system for Rust, written in Rust
 
         This method will build a cache directory, then it will fetch the
@@ -458,43 +458,34 @@ def download_toolchain(self, stage0=True, rustc_channel=None):
         """
         if rustc_channel is None:
             rustc_channel = self.stage0_compiler.version
-        bin_root = self.bin_root(stage0)
+        bin_root = self.bin_root()
 
         key = self.stage0_compiler.date
-        if not stage0:
-            key += str(self.rustc_commit)
-        if self.rustc(stage0).startswith(bin_root) and \
-                (not os.path.exists(self.rustc(stage0)) or
-                 self.program_out_of_date(self.rustc_stamp(stage0), key)):
+        if self.rustc().startswith(bin_root) and \
+                (not os.path.exists(self.rustc()) or
+                 self.program_out_of_date(self.rustc_stamp(), key)):
             if os.path.exists(bin_root):
                 shutil.rmtree(bin_root)
             tarball_suffix = '.tar.xz' if support_xz() else '.tar.gz'
             filename = "rust-std-{}-{}{}".format(
                 rustc_channel, self.build, tarball_suffix)
             pattern = "rust-std-{}".format(self.build)
-            self._download_component_helper(filename, pattern, tarball_suffix, stage0)
+            self._download_component_helper(filename, pattern, tarball_suffix)
             filename = "rustc-{}-{}{}".format(rustc_channel, self.build,
                                               tarball_suffix)
-            self._download_component_helper(filename, "rustc", tarball_suffix, stage0)
-            # download-rustc doesn't need its own cargo, it can just use beta's.
-            if stage0:
-                filename = "cargo-{}-{}{}".format(rustc_channel, self.build,
-                                                tarball_suffix)
-                self._download_component_helper(filename, "cargo", tarball_suffix)
-                self.fix_bin_or_dylib("{}/bin/cargo".format(bin_root))
-            else:
-                filename = "rustc-dev-{}-{}{}".format(rustc_channel, self.build, tarball_suffix)
-                self._download_component_helper(
-                    filename, "rustc-dev", tarball_suffix, stage0
-                )
+            self._download_component_helper(filename, "rustc", tarball_suffix)
+            filename = "cargo-{}-{}{}".format(rustc_channel, self.build,
+                                            tarball_suffix)
+            self._download_component_helper(filename, "cargo", tarball_suffix)
+            self.fix_bin_or_dylib("{}/bin/cargo".format(bin_root))
 
             self.fix_bin_or_dylib("{}/bin/rustc".format(bin_root))
             self.fix_bin_or_dylib("{}/bin/rustdoc".format(bin_root))
             lib_dir = "{}/lib".format(bin_root)
             for lib in os.listdir(lib_dir):
                 if lib.endswith(".so"):
                     self.fix_bin_or_dylib(os.path.join(lib_dir, lib))
-            with output(self.rustc_stamp(stage0)) as rust_stamp:
+            with output(self.rustc_stamp()) as rust_stamp:
                 rust_stamp.write(key)
 
         if self.rustfmt() and self.rustfmt().startswith(bin_root) and (
@@ -518,24 +509,17 @@ def download_toolchain(self, stage0=True, rustc_channel=None):
                     rustfmt_stamp.write(self.stage0_rustfmt.channel())
 
     def _download_component_helper(
-        self, filename, pattern, tarball_suffix, stage0=True, key=None
+        self, filename, pattern, tarball_suffix, key=None
     ):
         if key is None:
-            if stage0:
-                key = self.stage0_compiler.date
-            else:
-                key = self.rustc_commit
+            key = self.stage0_compiler.date
         cache_dst = os.path.join(self.build_dir, "cache")
         rustc_cache = os.path.join(cache_dst, key)
         if not os.path.exists(rustc_cache):
             os.makedirs(rustc_cache)
 
-        if stage0:
-            base = self._download_url
-            url = "dist/{}".format(key)
-        else:
-            base = "https://ci-artifacts.rust-lang.org"
-            url = "rustc-builds/{}".format(self.rustc_commit)
+        base = self._download_url
+        url = "dist/{}".format(key)
         tarball = os.path.join(rustc_cache, filename)
         if not os.path.exists(tarball):
             get(
@@ -544,9 +528,9 @@ def _download_component_helper(
                 tarball,
                 self.checksums_sha256,
                 verbose=self.verbose,
-                do_verify=stage0,
+                do_verify=True,
             )
-        unpack(tarball, tarball_suffix, self.bin_root(stage0), match=pattern, verbose=self.verbose)
+        unpack(tarball, tarball_suffix, self.bin_root(), match=pattern, verbose=self.verbose)
 
     def fix_bin_or_dylib(self, fname):
         """Modifies the interpreter section of 'fname' to fix the dynamic linker,
@@ -689,17 +673,15 @@ def maybe_download_ci_toolchain(self):
         # FIXME: support downloading artifacts from the beta channel
         self.download_toolchain(False, "nightly")
 
-    def rustc_stamp(self, stage0):
+    def rustc_stamp(self):
         """Return the path for .rustc-stamp at the given stage
 
         >>> rb = RustBuild()
         >>> rb.build_dir = "build"
-        >>> rb.rustc_stamp(True) == os.path.join("build", "stage0", ".rustc-stamp")
-        True
-        >>> rb.rustc_stamp(False) == os.path.join("build", "ci-rustc", ".rustc-stamp")
+        >>> rb.rustc_stamp() == os.path.join("build", "stage0", ".rustc-stamp")
         True
         """
-        return os.path.join(self.bin_root(stage0), '.rustc-stamp')
+        return os.path.join(self.bin_root(), '.rustc-stamp')
 
     def rustfmt_stamp(self):
         """Return the path for .rustfmt-stamp
@@ -709,7 +691,7 @@ def rustfmt_stamp(self):
         >>> rb.rustfmt_stamp() == os.path.join("build", "stage0", ".rustfmt-stamp")
         True
         """
-        return os.path.join(self.bin_root(True), '.rustfmt-stamp')
+        return os.path.join(self.bin_root(), '.rustfmt-stamp')
 
     def program_out_of_date(self, stamp_path, key):
         """Check if the given program stamp is out of date"""
@@ -718,26 +700,21 @@ def program_out_of_date(self, stamp_path, key):
         with open(stamp_path, 'r') as stamp:
             return key != stamp.read()
 
-    def bin_root(self, stage0):
+    def bin_root(self):
         """Return the binary root directory for the given stage
 
         >>> rb = RustBuild()
         >>> rb.build_dir = "build"
-        >>> rb.bin_root(True) == os.path.join("build", "stage0")
-        True
-        >>> rb.bin_root(False) == os.path.join("build", "ci-rustc")
+        >>> rb.bin_root() == os.path.join("build", "stage0")
         True
 
         When the 'build' property is given should be a nested directory:
 
         >>> rb.build = "devel"
-        >>> rb.bin_root(True) == os.path.join("build", "devel", "stage0")
+        >>> rb.bin_root() == os.path.join("build", "devel", "stage0")
         True
         """
-        if stage0:
-            subdir = "stage0"
-        else:
-            subdir = "ci-rustc"
+        subdir = "stage0"
         return os.path.join(self.build_dir, self.build, subdir)
 
     def get_toml(self, key, section=None):
@@ -785,37 +762,33 @@ def cargo(self):
         """Return config path for cargo"""
         return self.program_config('cargo')
 
-    def rustc(self, stage0):
+    def rustc(self):
         """Return config path for rustc"""
-        return self.program_config('rustc', stage0)
+        return self.program_config('rustc')
 
     def rustfmt(self):
         """Return config path for rustfmt"""
         if self.stage0_rustfmt is None:
             return None
         return self.program_config('rustfmt')
 
-    def program_config(self, program, stage0=True):
+    def program_config(self, program):
         """Return config path for the given program at the given stage
 
         >>> rb = RustBuild()
         >>> rb.config_toml = 'rustc = "rustc"\\n'
         >>> rb.program_config('rustc')
         'rustc'
         >>> rb.config_toml = ''
-        >>> cargo_path = rb.program_config('cargo', True)
-        >>> cargo_path.rstrip(".exe") == os.path.join(rb.bin_root(True),
-        ... "bin", "cargo")
-        True
-        >>> cargo_path = rb.program_config('cargo', False)
-        >>> cargo_path.rstrip(".exe") == os.path.join(rb.bin_root(False),
+        >>> cargo_path = rb.program_config('cargo')
+        >>> cargo_path.rstrip(".exe") == os.path.join(rb.bin_root(),
         ... "bin", "cargo")
         True
         """
         config = self.get_toml(program)
         if config:
             return os.path.expanduser(config)
-        return os.path.join(self.bin_root(stage0), "bin", "{}{}".format(
+        return os.path.join(self.bin_root(), "bin", "{}{}".format(
             program, self.exe_suffix()))
 
     @staticmethod
@@ -871,14 +844,14 @@ def build_bootstrap(self):
         if "CARGO_BUILD_TARGET" in env:
             del env["CARGO_BUILD_TARGET"]
         env["CARGO_TARGET_DIR"] = build_dir
-        env["RUSTC"] = self.rustc(True)
-        env["LD_LIBRARY_PATH"] = os.path.join(self.bin_root(True), "lib") + \
+        env["RUSTC"] = self.rustc()
+        env["LD_LIBRARY_PATH"] = os.path.join(self.bin_root(), "lib") + \
             (os.pathsep + env["LD_LIBRARY_PATH"]) \
             if "LD_LIBRARY_PATH" in env else ""
-        env["DYLD_LIBRARY_PATH"] = os.path.join(self.bin_root(True), "lib") + \
+        env["DYLD_LIBRARY_PATH"] = os.path.join(self.bin_root(), "lib") + \
             (os.pathsep + env["DYLD_LIBRARY_PATH"]) \
             if "DYLD_LIBRARY_PATH" in env else ""
-        env["LIBRARY_PATH"] = os.path.join(self.bin_root(True), "lib") + \
+        env["LIBRARY_PATH"] = os.path.join(self.bin_root(), "lib") + \
             (os.pathsep + env["LIBRARY_PATH"]) \
             if "LIBRARY_PATH" in env else ""
 
@@ -900,7 +873,7 @@ def build_bootstrap(self):
         if self.get_toml("deny-warnings", "rust") != "false":
             env["RUSTFLAGS"] += " -Dwarnings"
 
-        env["PATH"] = os.path.join(self.bin_root(True), "bin") + \
+        env["PATH"] = os.path.join(self.bin_root(), "bin") + \
             os.pathsep + env["PATH"]
         if not os.path.isfile(self.cargo()):
             raise Exception("no cargo executable found at `{}`".format(
@@ -1172,7 +1145,7 @@ def bootstrap(help_triggered):
     # Fetch/build the bootstrap
     build.download_toolchain()
     # Download the master compiler if `download-rustc` is set
-    build.maybe_download_ci_toolchain()
+    # build.maybe_download_ci_toolchain()
     sys.stdout.flush()
     build.ensure_vendored()
     build.build_bootstrap()

src/bootstrap/builder.rs

@@ -915,15 +915,12 @@ impl<'a> Builder<'a> {
         }
     }
 
-    pub(crate) fn unpack(&self, tarball: &Path, dst: &Path) {
+    pub(crate) fn unpack(&self, tarball: &Path, dst: &Path, pattern: &str) {
         println!("extracting {} to {}", tarball.display(), dst.display());
         if !dst.exists() {
             t!(fs::create_dir_all(dst));
         }
 
-        // FIXME: will need to be a parameter once `download-rustc` is moved to rustbuild
-        const MATCH: &str = "rust-dev";
-
         // `tarball` ends with `.tar.xz`; strip that suffix
         // example: `rust-dev-nightly-x86_64-unknown-linux-gnu`
         let uncompressed_filename =
@@ -943,10 +940,10 @@ impl<'a> Builder<'a> {
                 continue;
             }
             let mut short_path = t!(original_path.strip_prefix(directory_prefix));
-            if !short_path.starts_with(MATCH) {
+            if !short_path.starts_with(pattern) {
                 continue;
             }
-            short_path = t!(short_path.strip_prefix(MATCH));
+            short_path = t!(short_path.strip_prefix(pattern));
             let dst_path = dst.join(short_path);
             self.verbose(&format!("extracting {} to {}", original_path.display(), dst.display()));
             if !t!(member.unpack_in(dst)) {
@@ -1022,7 +1019,7 @@ impl<'a> Builder<'a> {
                     .join("lib");
                 // Avoid deleting the rustlib/ directory we just copied
                 // (in `impl Step for Sysroot`).
-                if !builder.config.download_rustc {
+                if !builder.download_rustc() {
                     let _ = fs::remove_dir_all(&sysroot);
                     t!(fs::create_dir_all(&sysroot));
                 }
@@ -1179,6 +1176,10 @@ impl<'a> Builder<'a> {
         Config::llvm_link_shared(self)
     }
 
+    pub(crate) fn download_rustc(&self) -> bool {
+        Config::download_rustc(self)
+    }
+
     /// Prepares an invocation of `cargo` to be run.
     ///
     /// This will create a `Command` that represents a pending execution of

src/bootstrap/compile.rs

@@ -42,8 +42,10 @@ impl Step for Std {
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
         // When downloading stage1, the standard library has already been copied to the sysroot, so
         // there's no need to rebuild it.
-        let download_rustc = run.builder.config.download_rustc;
-        run.all_krates("test").path("library").default_condition(!download_rustc)
+        let builder = run.builder;
+        run.all_krates("test")
+            .path("library")
+            .lazy_default_condition(Box::new(|| !builder.download_rustc()))
     }
 
     fn make_run(run: RunConfig<'_>) {
@@ -66,7 +68,7 @@ impl Step for Std {
         // Don't recompile them.
         // NOTE: the ABI of the beta compiler is different from the ABI of the downloaded compiler,
         // so its artifacts can't be reused.
-        if builder.config.download_rustc && compiler.stage != 0 {
+        if builder.download_rustc() && compiler.stage != 0 {
             return;
         }
 
@@ -551,7 +553,7 @@ impl Step for Rustc {
 
         // NOTE: the ABI of the beta compiler is different from the ABI of the downloaded compiler,
         // so its artifacts can't be reused.
-        if builder.config.download_rustc && compiler.stage != 0 {
+        if builder.download_rustc() && compiler.stage != 0 {
             // Copy the existing artifacts instead of rebuilding them.
             // NOTE: this path is only taken for tools linking to rustc-dev.
             builder.ensure(Sysroot { compiler });
@@ -995,7 +997,7 @@ impl Step for Sysroot {
         t!(fs::create_dir_all(&sysroot));
 
         // If we're downloading a compiler from CI, we can use the same compiler for all stages other than 0.
-        if builder.config.download_rustc && compiler.stage != 0 {
+        if builder.download_rustc() && compiler.stage != 0 {
             assert_eq!(
                 builder.config.build, compiler.host,
                 "Cross-compiling is not yet supported with `download-rustc`",
@@ -1090,7 +1092,7 @@ impl Step for Assemble {
         let build_compiler = builder.compiler(target_compiler.stage - 1, builder.config.build);
 
         // If we're downloading a compiler from CI, we can use the same compiler for all stages other than 0.
-        if builder.config.download_rustc {
+        if builder.download_rustc() {
             builder.ensure(Sysroot { compiler: target_compiler });
             return target_compiler;
         }