Rollup merge of #141970 - onur-ozkan:skip-stage1-std, r=Kobzol

implement new `x` flag: `--skip-std-check-if-no-download-rustc`

One of our developers (``@RalfJung)`` [reported](https://rust-lang.zulipchat.com/#narrow/channel/326414-t-infra.2Fbootstrap/topic/Surprising.20stages.20for.20check.20build.20after.20stage.20reorg/with/521925606)[#t-infra/bootstrap > Surprising stages for check build after stage reorg](https://rust-lang.zulipchat.com/#narrow/channel/326414-t-infra.2Fbootstrap/topic/Surprising.20stages.20for.20check.20build.20after.20stage.20reorg/with/521925606) that working on both the compiler and the library simultaneously with RA enabled is extremely difficult because checking library creates a heavy load on machines (by building stage1 compiler) on each modification. `--skip-std-check-if-no-download-rustc` flag is intended to reduce this heavy load on their IDE integration as much as possible.

Fixes: #141955

Author: matthiaskrgr

src/bootstrap/src/core/build_steps/check.rs

@@ -77,6 +77,13 @@ impl Step for Std {
     }
 
     fn run(self, builder: &Builder<'_>) {
+        if !builder.download_rustc() && builder.config.skip_std_check_if_no_download_rustc {
+            eprintln!(
+                "WARNING: `--skip-std-check-if-no-download-rustc` flag was passed and `rust.download-rustc` is not available. Skipping."
+            );
+            return;
+        }
+
         builder.require_submodule("library/stdarch", None);
 
         let stage = self.custom_stage.unwrap_or(builder.top_stage);

src/bootstrap/src/core/config/config.rs

@@ -423,6 +423,11 @@ pub struct Config {
 
     /// Cache for determining path modifications
     pub path_modification_cache: Arc<Mutex<HashMap<Vec<&'static str>, PathFreshness>>>,
+
+    /// Skip checking the standard library if `rust.download-rustc` isn't available.
+    /// This is mostly for RA as building the stage1 compiler to check the library tree
+    /// on each code change might be too much for some computers.
+    pub skip_std_check_if_no_download_rustc: bool,
 }
 
 #[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
@@ -1507,6 +1512,7 @@ impl Config {
         config.enable_bolt_settings = flags.enable_bolt_settings;
         config.bypass_bootstrap_lock = flags.bypass_bootstrap_lock;
         config.is_running_on_ci = flags.ci.unwrap_or(CiEnv::is_ci());
+        config.skip_std_check_if_no_download_rustc = flags.skip_std_check_if_no_download_rustc;
 
         // Infer the rest of the configuration.
 

src/bootstrap/src/core/config/flags.rs

@@ -182,6 +182,11 @@ pub struct Flags {
     /// Make bootstrap to behave as it's running on the CI environment or not.
     #[arg(global = true, long, value_name = "bool")]
     pub ci: Option<bool>,
+    /// Skip checking the standard library if `rust.download-rustc` isn't available.
+    /// This is mostly for RA as building the stage1 compiler to check the library tree
+    /// on each code change might be too much for some computers.
+    #[arg(global = true, long)]
+    pub skip_std_check_if_no_download_rustc: bool,
 }
 
 impl Flags {

src/bootstrap/src/utils/change_tracker.rs

@@ -416,4 +416,9 @@ pub const CONFIG_CHANGE_HISTORY: &[ChangeInfo] = &[
         severity: ChangeSeverity::Warning,
         summary: "Stage0 library no longer matches the in-tree library, which means stage1 compiler now uses the beta library.",
     },
+    ChangeInfo {
+        change_id: 141970,
+        severity: ChangeSeverity::Info,
+        summary: "Added new bootstrap flag `--skip-std-check-if-no-download-rustc` that skips std checks when download-rustc is unavailable. Mainly intended for developers to reduce RA overhead.",
+    },
 ];

src/doc/rustc-dev-guide/src/building/suggested.md

@@ -59,6 +59,14 @@ always overrides the inner ones.
 
 ## Configuring `rust-analyzer` for `rustc`
 
+### Checking the "library" tree
+
+Checking the "library" tree requires a stage1 compiler, which can be a heavy process on some computers.
+For this reason, bootstrap has a flag called `--skip-std-check-if-no-download-rustc` that skips checking the
+"library" tree if `rust.download-rustc` isn't available. If you want to avoid putting a heavy load on your computer
+with `rust-analyzer`, you can add the `--skip-std-check-if-no-download-rustc` flag to your `./x check` command in
+the `rust-analyzer` configuration.
+
 ### Project-local rust-analyzer setup
 
 `rust-analyzer` can help you check and format your code whenever you save a

src/etc/completions/x.fish

@@ -51,6 +51,7 @@ _x.py() {
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '::paths -- paths for the subcommand:_files' \
@@ -102,6 +103,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -146,6 +148,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -196,6 +199,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -239,6 +243,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -284,6 +289,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -329,6 +335,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -386,6 +393,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -433,6 +441,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -477,6 +486,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -521,6 +531,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -564,6 +575,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -607,6 +619,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -651,6 +664,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -694,6 +708,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '::profile -- Either the profile for `bootstrap.toml` or another setup action. May be omitted to set up interactively:_files' \
@@ -739,6 +754,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -784,6 +800,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -827,6 +844,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '::paths -- paths for the subcommand:_files' \
@@ -882,6 +900,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -928,6 +947,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -974,6 +994,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 '*::paths -- paths for the subcommand:_files' \
@@ -1020,6 +1041,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 ':benchmark-id -- Identifier to associate benchmark results with:_default' \
@@ -1064,6 +1086,7 @@ _arguments "${_arguments_options[@]}" : \
 '--llvm-profile-generate[generate PGO profile with llvm built for rustc]' \
 '--enable-bolt-settings[Enable BOLT link flags]' \
 '--skip-stage0-validation[Skip stage0 compiler validation]' \
+'--skip-std-check-if-no-download-rustc[Skip checking the standard library if \`rust.download-rustc\` isn'\''t available. This is mostly for RA as building the stage1 compiler to check the library tree on each code change might be too much for some computers]' \
 '-h[Print help (see more with '\''--help'\'')]' \
 '--help[Print help (see more with '\''--help'\'')]' \
 ':base -- The name of the base artifact to be compared:_default' \