bootstrap: move the version number to a plaintext file

The Rust version number is currently embedded in bootstrap's source
code, which makes it hard to update it automatically or access it
outside of ./x.py (as you'd have to parse the source code).

This commit moves the version number to a standalone plaintext file,
which makes accessing or updating it trivial.

src/bootstrap/channel.rs

@@ -12,9 +12,6 @@ use build_helper::output;
 
 use crate::Build;
 
-// The version number
-pub const CFG_RELEASE_NUM: &str = "1.48.0";
-
 pub struct GitInfo {
     inner: Option<Info>,
 }

src/bootstrap/dist.rs

@@ -18,7 +18,6 @@ use build_helper::{output, t};
 
 use crate::builder::{Builder, RunConfig, ShouldRun, Step};
 use crate::cache::{Interned, INTERNER};
-use crate::channel;
 use crate::compile;
 use crate::config::TargetSelection;
 use crate::tool::{self, Tool};
@@ -569,7 +568,7 @@ impl Step for Rustc {
                     &page_dst,
                     &[
                         ("<INSERT DATE HERE>", &month_year),
-                        ("<INSERT VERSION HERE>", channel::CFG_RELEASE_NUM),
+                        ("<INSERT VERSION HERE>", &builder.version),
                     ],
                 );
             }
@@ -2289,9 +2288,9 @@ impl Step for Extended {
 }
 
 fn add_env(builder: &Builder<'_>, cmd: &mut Command, target: TargetSelection) {
-    let mut parts = channel::CFG_RELEASE_NUM.split('.');
+    let mut parts = builder.version.split('.');
     cmd.env("CFG_RELEASE_INFO", builder.rust_version())
-        .env("CFG_RELEASE_NUM", channel::CFG_RELEASE_NUM)
+        .env("CFG_RELEASE_NUM", &builder.version)
         .env("CFG_RELEASE", builder.rust_release())
         .env("CFG_VER_MAJOR", parts.next().unwrap())
         .env("CFG_VER_MINOR", parts.next().unwrap())

src/bootstrap/doc.rs

@@ -433,7 +433,7 @@ impl Step for Std {
                 .arg("-Z")
                 .arg("unstable-options")
                 .arg("--resource-suffix")
-                .arg(crate::channel::CFG_RELEASE_NUM)
+                .arg(&builder.version)
                 .arg("--index-page")
                 .arg(&builder.src.join("src/doc/index.md"));
 
@@ -659,7 +659,7 @@ impl Step for ErrorIndex {
         let mut index = tool::ErrorIndex::command(builder, self.compiler);
         index.arg("html");
         index.arg(out.join("error-index.html"));
-        index.arg(crate::channel::CFG_RELEASE_NUM);
+        index.arg(&builder.version);
 
         builder.run(&mut index);
     }

src/bootstrap/lib.rs

@@ -218,6 +218,9 @@ pub struct Build {
     /// User-specified configuration from `config.toml`.
     config: Config,
 
+    // Version information
+    version: String,
+
     // Properties derived from the above configuration
     src: PathBuf,
     out: PathBuf,
@@ -380,6 +383,10 @@ impl Build {
             .unwrap()
             .to_path_buf();
 
+        let version = std::fs::read_to_string(src.join("src").join("version"))
+            .expect("failed to read src/version");
+        let version = version.trim();
+
         let mut build = Build {
             initial_rustc: config.initial_rustc.clone(),
             initial_cargo: config.initial_cargo.clone(),
@@ -395,6 +402,7 @@ impl Build {
             targets: config.targets.clone(),
 
             config,
+            version: version.to_string(),
             src,
             out,
 
@@ -433,8 +441,7 @@ impl Build {
             .next()
             .unwrap()
             .trim();
-        let my_version = channel::CFG_RELEASE_NUM;
-        if local_release.split('.').take(2).eq(my_version.split('.').take(2)) {
+        if local_release.split('.').take(2).eq(version.split('.').take(2)) {
             build.verbose(&format!("auto-detected local-rebuild {}", local_release));
             build.local_rebuild = true;
         }
@@ -785,7 +792,7 @@ impl Build {
 
         match which {
             GitRepo::Rustc => {
-                let sha = self.rust_sha().unwrap_or(channel::CFG_RELEASE_NUM);
+                let sha = self.rust_sha().unwrap_or(&self.version);
                 Some(format!("/rustc/{}", sha))
             }
             GitRepo::Llvm => Some(String::from("/rustc/llvm")),
@@ -1016,7 +1023,7 @@ impl Build {
 
     /// Returns the value of `release` above for Rust itself.
     fn rust_release(&self) -> String {
-        self.release(channel::CFG_RELEASE_NUM)
+        self.release(&self.version)
     }
 
     /// Returns the "package version" for a component given the `num` release
@@ -1036,7 +1043,7 @@ impl Build {
 
     /// Returns the value of `package_vers` above for Rust itself.
     fn rust_package_vers(&self) -> String {
-        self.package_vers(channel::CFG_RELEASE_NUM)
+        self.package_vers(&self.version)
     }
 
     /// Returns the value of `package_vers` above for Cargo
@@ -1070,7 +1077,7 @@ impl Build {
     }
 
     fn llvm_tools_package_vers(&self) -> String {
-        self.package_vers(channel::CFG_RELEASE_NUM)
+        self.package_vers(&self.version)
     }
 
     fn llvm_tools_vers(&self) -> String {
@@ -1087,7 +1094,7 @@ impl Build {
     /// Note that this is a descriptive string which includes the commit date,
     /// sha, version, etc.
     fn rust_version(&self) -> String {
-        self.rust_info.version(self, channel::CFG_RELEASE_NUM)
+        self.rust_info.version(self, &self.version)
     }
 
     /// Returns the full commit hash.

src/bootstrap/native.rs

@@ -19,7 +19,6 @@ use std::process::Command;
 use build_helper::{output, t};
 
 use crate::builder::{Builder, RunConfig, ShouldRun, Step};
-use crate::channel;
 use crate::config::TargetSelection;
 use crate::util::{self, exe};
 use crate::GitRepo;
@@ -296,7 +295,7 @@ impl Step for Llvm {
             // release number on the dev channel.
             cfg.define("LLVM_VERSION_SUFFIX", "-rust-dev");
         } else {
-            let suffix = format!("-rust-{}-{}", channel::CFG_RELEASE_NUM, builder.config.channel);
+            let suffix = format!("-rust-{}-{}", builder.version, builder.config.channel);
             cfg.define("LLVM_VERSION_SUFFIX", suffix);
         }
 

src/bootstrap/test.rs

@@ -636,7 +636,7 @@ impl Step for RustdocJSStd {
                 .arg("--crate-name")
                 .arg("std")
                 .arg("--resource-suffix")
-                .arg(crate::channel::CFG_RELEASE_NUM)
+                .arg(&builder.version)
                 .arg("--doc-folder")
                 .arg(builder.doc_out(self.target))
                 .arg("--test-folder")

src/bootstrap/tool.rs

@@ -7,7 +7,6 @@ use std::process::{exit, Command};
 use build_helper::t;
 
 use crate::builder::{Builder, Cargo as CargoCommand, RunConfig, ShouldRun, Step};
-use crate::channel;
 use crate::channel::GitInfo;
 use crate::compile;
 use crate::config::TargetSelection;
@@ -255,7 +254,7 @@ pub fn prepare_tool_cargo(
     cargo.env("CFG_RELEASE", builder.rust_release());
     cargo.env("CFG_RELEASE_CHANNEL", &builder.config.channel);
     cargo.env("CFG_VERSION", builder.rust_version());
-    cargo.env("CFG_RELEASE_NUM", channel::CFG_RELEASE_NUM);
+    cargo.env("CFG_RELEASE_NUM", &builder.version);
 
     let info = GitInfo::new(builder.config.ignore_git, &dir);
     if let Some(sha) = info.sha() {

src/version

@@ -0,0 +1 @@
+1.48.0