Auto merge of rust-lang#143048 - Kobzol:bootstrap-check-stage-1, r=jieyouxu

Enforce in bootstrap that check must have stage at least 1

This PR is another step towards https://rust-lang.zulipchat.com/#narrow/channel/326414-t-infra.2Fbootstrap/topic/Proposal.20to.20cleanup.20stages.20and.20steps.20after.20the.20redesign/with/523586917, this time dealing with `x check`.

It enforces the invariant that:
- We check std stage N with rustc stage N
- We check everything else stage N with rustc stage N - 1

It creates a single function that prepares a proper build compiler for checking something, and also adds snapshot tests for various common check steps. Some obsolete code was also removed.

The default check stage also becomes 1, for all profiles. I tested manually that `x check std` with `download-ci-rustc` still works and doesn't build rustc locally.

Closes: rust-lang#139170

r? `@ghost`

Author: bors

src/bootstrap/defaults/bootstrap.library.toml

@@ -1,7 +1,6 @@
 # These defaults are meant for contributors to the standard library and documentation.
 [build]
 bench-stage = 1
-check-stage = 1
 test-stage = 1
 
 [rust]

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

@@ -215,7 +215,7 @@ impl Step for Rustc {
                 builder.std(compiler, compiler.host);
                 builder.std(compiler, target);
             } else {
-                builder.ensure(check::Std::new(target));
+                builder.ensure(check::Std::new(compiler, target));
             }
         }
 
@@ -287,7 +287,7 @@ macro_rules! lint_any {
                 let target = self.target;
 
                 if !builder.download_rustc() {
-                    builder.ensure(check::Rustc::new(target, builder));
+                    builder.ensure(check::Rustc::new(builder, compiler, target));
                 };
 
                 let cargo = prepare_tool_cargo(

src/bootstrap/src/core/build_steps/clippy.rs

@@ -1741,17 +1741,19 @@ fn copy_codegen_backends_to_sysroot(
         }
 
         let stamp = build_stamp::codegen_backend_stamp(builder, compiler, target, backend);
-        let dylib = t!(fs::read_to_string(stamp.path()));
-        let file = Path::new(&dylib);
-        let filename = file.file_name().unwrap().to_str().unwrap();
-        // change `librustc_codegen_cranelift-xxxxxx.so` to
-        // `librustc_codegen_cranelift-release.so`
-        let target_filename = {
-            let dash = filename.find('-').unwrap();
-            let dot = filename.find('.').unwrap();
-            format!("{}-{}{}", &filename[..dash], builder.rust_release(), &filename[dot..])
-        };
-        builder.copy_link(file, &dst.join(target_filename), FileType::NativeLibrary);
+        if stamp.path().exists() {
+            let dylib = t!(fs::read_to_string(stamp.path()));
+            let file = Path::new(&dylib);
+            let filename = file.file_name().unwrap().to_str().unwrap();
+            // change `librustc_codegen_cranelift-xxxxxx.so` to
+            // `librustc_codegen_cranelift-release.so`
+            let target_filename = {
+                let dash = filename.find('-').unwrap();
+                let dot = filename.find('.').unwrap();
+                format!("{}-{}{}", &filename[..dash], builder.rust_release(), &filename[dot..])
+            };
+            builder.copy_link(file, &dst.join(target_filename), FileType::NativeLibrary);
+        }
     }
 }
 
@@ -2162,6 +2164,25 @@ impl Step for Assemble {
                 continue; // Already built as part of rustc
             }
 
+            // FIXME: this is a horrible hack used to make `x check` work when other codegen
+            // backends are enabled.
+            // `x check` will check stage 1 rustc, which copies its rmetas to the stage0 sysroot.
+            // Then it checks codegen backends, which correctly use these rmetas.
+            // Then it needs to check std, but for that it needs to build stage 1 rustc.
+            // This copies the build rmetas into the stage0 sysroot, effectively poisoning it,
+            // because we then have both check and build rmetas in the same sysroot.
+            // That would be fine on its own. However, when another codegen backend is enabled,
+            // then building stage 1 rustc implies also building stage 1 codegen backend (even if
+            // it isn't used for anything). And since that tries to use the poisoned
+            // rmetas, it fails to build.
+            // We don't actually need to build rustc-private codegen backends for checking std,
+            // so instead we skip that.
+            // Note: this would be also an issue for other rustc-private tools, but that is "solved"
+            // by check::Std being last in the list of checked things (see
+            // `Builder::get_step_descriptions`).
+            if builder.kind == Kind::Check && builder.top_stage == 1 {
+                continue;
+            }
             builder.ensure(CodegenBackend {
                 compiler: build_compiler,
                 target: target_compiler.host,

src/bootstrap/src/core/build_steps/compile.rs

@@ -263,6 +263,15 @@ impl Step for Llvm {
     }
 
     /// Compile LLVM for `target`.
+    #[cfg_attr(
+        feature = "tracing",
+        instrument(
+            level = "debug",
+            name = "Llvm::run",
+            skip_all,
+            fields(target = ?self.target),
+        ),
+    )]
     fn run(self, builder: &Builder<'_>) -> LlvmResult {
         let target = self.target;
         let target_native = if self.target.starts_with("riscv") {

src/bootstrap/src/core/build_steps/llvm.rs

@@ -77,7 +77,7 @@ impl Builder<'_> {
                 *target,
             ),
             // doesn't depend on compiler, same as host compiler
-            _ => self.msg(Kind::Build, build_stage, format_args!("tool {tool}"), *host, *target),
+            _ => self.msg(kind, build_stage, format_args!("tool {tool}"), *host, *target),
         }
     }
 }

src/bootstrap/src/core/build_steps/tool.rs

@@ -1240,24 +1240,23 @@ mod snapshot {
             ctx.config("check")
                 .path("compiler")
                 .render_steps(), @r"
-        [check] std <host>
         [build] llvm <host>
-        [check] rustc <host>
-        [check] cranelift <host>
-        [check] gcc <host>
+        [check] rustc 0 <host> -> rustc 1 <host>
+        [check] rustc 0 <host> -> cranelift 1 <host>
+        [check] rustc 0 <host> -> gcc 1 <host>
         ");
 
         insta::assert_snapshot!(
             ctx.config("check")
                 .path("rustc")
                 .render_steps(), @r"
-        [check] std <host>
         [build] llvm <host>
-        [check] rustc <host>
+        [check] rustc 0 <host> -> rustc 1 <host>
         ");
     }
 
     #[test]
+    #[should_panic]
     fn check_compiler_stage_0() {
         let ctx = TestCtx::new();
         ctx.config("check").path("compiler").stage(0).run();
@@ -1272,11 +1271,9 @@ mod snapshot {
                 .stage(1)
                 .render_steps(), @r"
         [build] llvm <host>
-        [build] rustc 0 <host> -> rustc 1 <host>
-        [build] rustc 1 <host> -> std 1 <host>
-        [check] rustc <host>
-        [check] cranelift <host>
-        [check] gcc <host>
+        [check] rustc 0 <host> -> rustc 1 <host>
+        [check] rustc 0 <host> -> cranelift 1 <host>
+        [check] rustc 0 <host> -> gcc 1 <host>
         ");
     }
 
@@ -1291,11 +1288,9 @@ mod snapshot {
         [build] llvm <host>
         [build] rustc 0 <host> -> rustc 1 <host>
         [build] rustc 1 <host> -> std 1 <host>
-        [build] rustc 1 <host> -> rustc 2 <host>
-        [build] rustc 2 <host> -> std 2 <host>
-        [check] rustc <host>
-        [check] cranelift <host>
-        [check] gcc <host>
+        [check] rustc 1 <host> -> rustc 2 <host>
+        [check] rustc 1 <host> -> cranelift 2 <host>
+        [check] rustc 1 <host> -> gcc 2 <host>
         ");
     }
 
@@ -1304,30 +1299,24 @@ mod snapshot {
         let ctx = TestCtx::new();
         insta::assert_snapshot!(
             ctx.config("check")
-                .stage(2)
                 .targets(&[TEST_TRIPLE_1])
                 .hosts(&[TEST_TRIPLE_1])
                 .render_steps(), @r"
         [build] llvm <host>
         [build] rustc 0 <host> -> rustc 1 <host>
         [build] rustc 1 <host> -> std 1 <host>
-        [build] rustc 1 <host> -> rustc 2 <host>
-        [build] rustc 2 <host> -> std 2 <host>
         [build] rustc 1 <host> -> std 1 <target1>
-        [build] rustc 2 <host> -> std 2 <target1>
-        [check] rustc <target1>
-        [check] Rustdoc <target1>
-        [check] cranelift <target1>
-        [check] gcc <target1>
-        [check] Clippy <target1>
-        [check] Miri <target1>
-        [check] CargoMiri <target1>
-        [check] MiroptTestTools <target1>
-        [check] Rustfmt <target1>
-        [check] rust-analyzer <target1>
-        [check] TestFloatParse <target1>
-        [check] FeaturesStatusDump <target1>
-        [check] std <target1>
+        [check] rustc 1 <host> -> rustc 2 <target1>
+        [check] rustc 1 <host> -> Rustdoc 2 <target1>
+        [check] rustc 1 <host> -> cranelift 2 <target1>
+        [check] rustc 1 <host> -> gcc 2 <target1>
+        [check] rustc 1 <host> -> Clippy 2 <target1>
+        [check] rustc 1 <host> -> Miri 2 <target1>
+        [check] rustc 1 <host> -> CargoMiri 2 <target1>
+        [check] rustc 1 <host> -> Rustfmt 2 <target1>
+        [check] rustc 1 <host> -> rust-analyzer 2 <target1>
+        [check] rustc 1 <host> -> TestFloatParse 2 <target1>
+        [check] rustc 1 <host> -> std 1 <target1>
         ");
     }
 
@@ -1340,11 +1329,12 @@ mod snapshot {
                 .render_steps(), @r"
         [build] llvm <host>
         [build] rustc 0 <host> -> rustc 1 <host>
-        [check] std <host>
+        [check] rustc 1 <host> -> std 1 <host>
         ");
     }
 
     #[test]
+    #[should_panic]
     fn check_library_stage_0() {
         let ctx = TestCtx::new();
         ctx.config("check").path("library").stage(0).run();
@@ -1360,7 +1350,7 @@ mod snapshot {
                 .render_steps(), @r"
         [build] llvm <host>
         [build] rustc 0 <host> -> rustc 1 <host>
-        [check] std <host>
+        [check] rustc 1 <host> -> std 1 <host>
         ");
     }
 
@@ -1376,7 +1366,7 @@ mod snapshot {
         [build] rustc 0 <host> -> rustc 1 <host>
         [build] rustc 1 <host> -> std 1 <host>
         [build] rustc 1 <host> -> rustc 2 <host>
-        [check] std <host>
+        [check] rustc 2 <host> -> std 2 <host>
         ");
     }
 
@@ -1390,8 +1380,8 @@ mod snapshot {
                 .render_steps(), @r"
         [build] llvm <host>
         [build] rustc 0 <host> -> rustc 1 <host>
-        [check] std <target1>
-        [check] std <target2>
+        [check] rustc 1 <host> -> std 1 <target1>
+        [check] rustc 1 <host> -> std 1 <target2>
         ");
     }
 
@@ -1402,14 +1392,14 @@ mod snapshot {
             ctx.config("check")
                 .path("miri")
                 .render_steps(), @r"
-        [check] std <host>
         [build] llvm <host>
-        [check] rustc <host>
-        [check] Miri <host>
+        [check] rustc 0 <host> -> rustc 1 <host>
+        [check] rustc 0 <host> -> Miri 1 <host>
         ");
     }
 
     #[test]
+    #[should_panic]
     fn check_miri_stage_0() {
         let ctx = TestCtx::new();
         ctx.config("check").path("miri").stage(0).run();
@@ -1424,10 +1414,8 @@ mod snapshot {
                 .stage(1)
                 .render_steps(), @r"
         [build] llvm <host>
-        [build] rustc 0 <host> -> rustc 1 <host>
-        [build] rustc 1 <host> -> std 1 <host>
-        [check] rustc <host>
-        [check] Miri <host>
+        [check] rustc 0 <host> -> rustc 1 <host>
+        [check] rustc 0 <host> -> Miri 1 <host>
         ");
     }
 
@@ -1442,10 +1430,8 @@ mod snapshot {
         [build] llvm <host>
         [build] rustc 0 <host> -> rustc 1 <host>
         [build] rustc 1 <host> -> std 1 <host>
-        [build] rustc 1 <host> -> rustc 2 <host>
-        [build] rustc 2 <host> -> std 2 <host>
-        [check] rustc <host>
-        [check] Miri <host>
+        [check] rustc 1 <host> -> rustc 2 <host>
+        [check] rustc 1 <host> -> Miri 2 <host>
         ");
     }
 
@@ -1466,9 +1452,9 @@ mod snapshot {
                 .path("compiletest")
                 .args(&["--set", "build.compiletest-use-stage0-libtest=false"])
                 .render_steps(), @r"
-        [check] std <host>
         [build] llvm <host>
-        [check] rustc <host>
+        [build] rustc 0 <host> -> rustc 1 <host>
+        [build] rustc 1 <host> -> std 1 <host>
         [check] compiletest <host>
         ");
     }
@@ -1480,11 +1466,10 @@ mod snapshot {
             ctx.config("check")
                 .path("rustc_codegen_cranelift")
                 .render_steps(), @r"
-        [check] std <host>
         [build] llvm <host>
-        [check] rustc <host>
-        [check] cranelift <host>
-        [check] gcc <host>
+        [check] rustc 0 <host> -> rustc 1 <host>
+        [check] rustc 0 <host> -> cranelift 1 <host>
+        [check] rustc 0 <host> -> gcc 1 <host>
         ");
     }
 
@@ -1495,10 +1480,9 @@ mod snapshot {
             ctx.config("check")
                 .path("rust-analyzer")
                 .render_steps(), @r"
-        [check] std <host>
         [build] llvm <host>
-        [check] rustc <host>
-        [check] rust-analyzer <host>
+        [check] rustc 0 <host> -> rustc 1 <host>
+        [check] rustc 0 <host> -> rust-analyzer 1 <host>
         ");
     }
 
@@ -1508,12 +1492,7 @@ mod snapshot {
         insta::assert_snapshot!(
             ctx.config("check")
                 .path("run-make-support")
-                .render_steps(), @r"
-        [check] std <host>
-        [build] llvm <host>
-        [check] rustc <host>
-        [check] RunMakeSupport <host>
-        ");
+                .render_steps(), @"[check] rustc 0 <host> -> RunMakeSupport 1 <host>");
     }
 
     #[test]

src/bootstrap/src/core/builder/tests.rs

@@ -1025,7 +1025,7 @@ impl Config {
             || bench_stage.is_some();
 
         config.stage = match config.cmd {
-            Subcommand::Check { .. } => flags_stage.or(check_stage).unwrap_or(0),
+            Subcommand::Check { .. } => flags_stage.or(check_stage).unwrap_or(1),
             Subcommand::Clippy { .. } | Subcommand::Fix => flags_stage.or(check_stage).unwrap_or(1),
             // `download-rustc` only has a speed-up for stage2 builds. Default to stage2 unless explicitly overridden.
             Subcommand::Doc { .. } => {
@@ -1052,9 +1052,16 @@ impl Config {
         };
 
         // Now check that the selected stage makes sense, and if not, print a warning and end
-        if let (0, Subcommand::Build) = (config.stage, &config.cmd) {
-            eprintln!("WARNING: cannot build anything on stage 0. Use at least stage 1.");
-            exit!(1);
+        match (config.stage, &config.cmd) {
+            (0, Subcommand::Build) => {
+                eprintln!("WARNING: cannot build anything on stage 0. Use at least stage 1.");
+                exit!(1);
+            }
+            (0, Subcommand::Check { .. }) => {
+                eprintln!("WARNING: cannot check anything on stage 0. Use at least stage 1.");
+                exit!(1);
+            }
+            _ => {}
         }
 
         // CI should always run stage 2 builds, unless it specifically states otherwise

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

@@ -451,4 +451,9 @@ pub const CONFIG_CHANGE_HISTORY: &[ChangeInfo] = &[
         severity: ChangeSeverity::Warning,
         summary: "The `spellcheck:fix` tidy extra check argument has been removed, use `--bless` instead",
     },
+    ChangeInfo {
+        change_id: 143048,
+        severity: ChangeSeverity::Warning,
+        summary: "The default check stage has been changed to 1. It is no longer possible to `x check` with stage 0. All check commands have to be on stage 1+. Bootstrap tools can now also only be checked for the host target.",
+    },
 ];