Rollup merge of #47460 - Mark-Simulacrum:bootstrap-check, r=alexcrichton

Add ./x.py check src/{libstd,libtest,librustc}

This currently only supports a limited subset of the full compilation,
but is likely 90% of what people will want and is possible without
building a full compiler (and also building LLVM). In theory, this means
that contributors who don't want to build LLVM now have an easy way to
compile locally, though running tests won't work.

Author: alexcrichton

src/bootstrap/bin/rustc.rs

@@ -125,11 +125,6 @@ fn main() {
             cmd.arg(format!("-Clinker={}", target_linker));
         }
 
-        // Pass down incremental directory, if any.
-        if let Ok(dir) = env::var("RUSTC_INCREMENTAL") {
-            cmd.arg(format!("-Zincremental={}", dir));
-        }
-
         let crate_name = args.windows(2)
             .find(|a| &*a[0] == "--crate-name")
             .unwrap();

src/bootstrap/bootstrap.py

@@ -602,6 +602,7 @@ def build_bootstrap(self):
         env["LIBRARY_PATH"] = os.path.join(self.bin_root(), "lib") + \
             (os.pathsep + env["LIBRARY_PATH"]) \
             if "LIBRARY_PATH" in env else ""
+        env["RUSTFLAGS"] = "-Cdebuginfo=2"
         env["PATH"] = os.path.join(self.bin_root(), "bin") + \
             os.pathsep + env["PATH"]
         if not os.path.isfile(self.cargo()):

src/bootstrap/builder.rs

@@ -26,6 +26,7 @@ use util::{exe, libdir, add_lib_path};
 use {Build, Mode};
 use cache::{INTERNER, Interned, Cache};
 use check;
+use test;
 use flags::Subcommand;
 use doc;
 use tool;
@@ -230,6 +231,7 @@ impl<'a> ShouldRun<'a> {
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
 pub enum Kind {
     Build,
+    Check,
     Test,
     Bench,
     Dist,
@@ -251,13 +253,13 @@ impl<'a> Builder<'a> {
                 tool::Compiletest, tool::RemoteTestServer, tool::RemoteTestClient,
                 tool::RustInstaller, tool::Cargo, tool::Rls, tool::Rustdoc, tool::Clippy,
                 native::Llvm, tool::Rustfmt, tool::Miri),
-            Kind::Test => describe!(check::Tidy, check::Bootstrap, check::DefaultCompiletest,
-                check::HostCompiletest, check::Crate, check::CrateLibrustc, check::Rustdoc,
-                check::Linkcheck, check::Cargotest, check::Cargo, check::Rls, check::Docs,
-                check::ErrorIndex, check::Distcheck, check::Rustfmt, check::Miri, check::Clippy,
-                check::RustdocJS),
-
-            Kind::Bench => describe!(check::Crate, check::CrateLibrustc),
+            Kind::Check => describe!(check::Std, check::Test, check::Rustc),
+            Kind::Test => describe!(test::Tidy, test::Bootstrap, test::DefaultCompiletest,
+                test::HostCompiletest, test::Crate, test::CrateLibrustc, test::Rustdoc,
+                test::Linkcheck, test::Cargotest, test::Cargo, test::Rls, test::Docs,
+                test::ErrorIndex, test::Distcheck, test::Rustfmt, test::Miri, test::Clippy,
+                test::RustdocJS),
+            Kind::Bench => describe!(test::Crate, test::CrateLibrustc),
             Kind::Doc => describe!(doc::UnstableBook, doc::UnstableBookGen, doc::TheBook,
                 doc::Standalone, doc::Std, doc::Test, doc::Rustc, doc::ErrorIndex, doc::Nomicon,
                 doc::Reference, doc::Rustdoc, doc::RustByExample, doc::CargoBook),
@@ -304,6 +306,7 @@ impl<'a> Builder<'a> {
     pub fn run(build: &Build) {
         let (kind, paths) = match build.config.cmd {
             Subcommand::Build { ref paths } => (Kind::Build, &paths[..]),
+            Subcommand::Check { ref paths } => (Kind::Check, &paths[..]),
             Subcommand::Doc { ref paths } => (Kind::Doc, &paths[..]),
             Subcommand::Test { ref paths, .. } => (Kind::Test, &paths[..]),
             Subcommand::Bench { ref paths, .. } => (Kind::Bench, &paths[..]),
@@ -493,13 +496,14 @@ impl<'a> Builder<'a> {
             cargo.env("RUSTC_CODEGEN_UNITS", n.to_string());
         }
 
+
         if let Some(host_linker) = self.build.linker(compiler.host) {
             cargo.env("RUSTC_HOST_LINKER", host_linker);
         }
         if let Some(target_linker) = self.build.linker(target) {
             cargo.env("RUSTC_TARGET_LINKER", target_linker);
         }
-        if cmd != "build" {
+        if cmd != "build" && cmd != "check" {
             cargo.env("RUSTDOC_LIBDIR", self.rustc_libdir(self.compiler(2, self.build.build)));
         }
 
@@ -566,8 +570,7 @@ impl<'a> Builder<'a> {
         // not guaranteeing correctness across builds if the compiler
         // is changing under your feet.`
         if self.config.incremental && compiler.stage == 0 {
-            let incr_dir = self.incremental_dir(compiler);
-            cargo.env("RUSTC_INCREMENTAL", incr_dir);
+            cargo.env("CARGO_INCREMENTAL", "1");
         }
 
         if let Some(ref on_fail) = self.config.on_fail {