Auto merge of #117574 - onur-ozkan:fix-compiler-crate-linking, r=Mark-Simulacrum

improve compiler&tool documenting and re-enable cranelift on CI

First commit addresses the linking issue with compiler crates. Second one ensures that compiler crates are linked correctly (with later commits we added this check for tools as well), allowing us to detect these hard-to-catch bugs on CI. Following three commits cherry-picked from #117328 to re-enable the Cranelift backend on CI.

More info: https://github.com/rust-lang/rust/issues/117430

cc `@bjorn3` `@RalfJung`

4 files changed, 73 insertions, 57 deletions

diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index 1eed534150b..8ab0ef61c50 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -413,11 +413,6 @@ pub fn std_cargo(builder: &Builder<'_>, target: TargetSelection, stage: u32, car
 
     let mut features = String::new();
 
-    // Cranelift doesn't support `asm`.
-    if stage != 0 && builder.config.default_codegen_backend().unwrap_or_default() == "cranelift" {
-        features += " compiler-builtins-no-asm";
-    }
-
     if builder.no_std(target) == Some(true) {
         features += " compiler-builtins-mem";
         if !target.starts_with("bpf") {
diff --git a/src/bootstrap/src/core/build_steps/dist.rs b/src/bootstrap/src/core/build_steps/dist.rs
index b578c5ec295..6e80c55c8ce 100644
--- a/src/bootstrap/src/core/build_steps/dist.rs
+++ b/src/bootstrap/src/core/build_steps/dist.rs
@@ -1298,6 +1298,10 @@ impl Step for CodegenBackend {
     }
 
     fn run(self, builder: &Builder<'_>) -> Option<GeneratedTarball> {
+        if builder.config.dry_run() {
+            return None;
+        }
+
         // This prevents rustc_codegen_cranelift from being built for "dist"
         // or "install" on the stable/beta channels. It is not yet stable and
         // should not be included.
@@ -1305,6 +1309,10 @@ impl Step for CodegenBackend {
             return None;
         }
 
+        if !builder.config.rust_codegen_backends.contains(&self.backend) {
+            return None;
+        }
+
         if self.backend == "cranelift" {
             if !target_supports_cranelift_backend(self.compiler.host) {
                 builder.info("target not supported by rustc_codegen_cranelift. skipping");
@@ -1343,12 +1351,15 @@ impl Step for CodegenBackend {
         let backends_dst = PathBuf::from("lib").join(&backends_rel);
 
         let backend_name = format!("rustc_codegen_{}", backend);
+        let mut found_backend = false;
         for backend in fs::read_dir(&backends_src).unwrap() {
             let file_name = backend.unwrap().file_name();
             if file_name.to_str().unwrap().contains(&backend_name) {
                 tarball.add_file(backends_src.join(file_name), &backends_dst, 0o644);
+                found_backend = true;
             }
         }
+        assert!(found_backend);
 
         Some(tarball.generate())
     }
diff --git a/src/bootstrap/src/core/build_steps/doc.rs b/src/bootstrap/src/core/build_steps/doc.rs
index 628a4ece8e9..f2a185f70fe 100644
--- a/src/bootstrap/src/core/build_steps/doc.rs
+++ b/src/bootstrap/src/core/build_steps/doc.rs
@@ -685,19 +685,6 @@ impl Step for Rustc {
             target,
         );
 
-        // This uses a shared directory so that librustdoc documentation gets
-        // correctly built and merged with the rustc documentation. This is
-        // needed because rustdoc is built in a different directory from
-        // rustc. rustdoc needs to be able to see everything, for example when
-        // merging the search index, or generating local (relative) links.
-        let out_dir = builder.stage_out(compiler, Mode::Rustc).join(target.triple).join("doc");
-        t!(fs::create_dir_all(out_dir.parent().unwrap()));
-        symlink_dir_force(&builder.config, &out, &out_dir);
-        // Cargo puts proc macros in `target/doc` even if you pass `--target`
-        // explicitly (https://github.com/rust-lang/cargo/issues/7677).
-        let proc_macro_out_dir = builder.stage_out(compiler, Mode::Rustc).join("doc");
-        symlink_dir_force(&builder.config, &out, &proc_macro_out_dir);
-
         // Build cargo command.
         let mut cargo = builder.cargo(compiler, Mode::Rustc, SourceType::InTree, target, "doc");
         cargo.rustdocflag("--document-private-items");
@@ -724,6 +711,7 @@ impl Step for Rustc {
 
         let mut to_open = None;
 
+        let out_dir = builder.stage_out(compiler, Mode::Rustc).join(target.triple).join("doc");
         for krate in &*self.crates {
             // Create all crate output directories first to make sure rustdoc uses
             // relative links.
@@ -736,8 +724,29 @@ impl Step for Rustc {
             }
         }
 
+        // This uses a shared directory so that librustdoc documentation gets
+        // correctly built and merged with the rustc documentation.
+        //
+        // This is needed because rustdoc is built in a different directory from
+        // rustc. rustdoc needs to be able to see everything, for example when
+        // merging the search index, or generating local (relative) links.
+        symlink_dir_force(&builder.config, &out, &out_dir);
+        // Cargo puts proc macros in `target/doc` even if you pass `--target`
+        // explicitly (https://github.com/rust-lang/cargo/issues/7677).
+        let proc_macro_out_dir = builder.stage_out(compiler, Mode::Rustc).join("doc");
+        symlink_dir_force(&builder.config, &out, &proc_macro_out_dir);
+
         builder.run(&mut cargo.into());
 
+        if !builder.config.dry_run() {
+            // Sanity check on linked compiler crates
+            for krate in &*self.crates {
+                let dir_name = krate.replace("-", "_");
+                // Making sure the directory exists and is not empty.
+                assert!(out.join(&*dir_name).read_dir().unwrap().next().is_some());
+            }
+        }
+
         if builder.paths.iter().any(|path| path.ends_with("compiler")) {
             // For `x.py doc compiler --open`, open `rustc_middle` by default.
             let index = out.join("rustc_middle").join("index.html");
@@ -756,10 +765,10 @@ macro_rules! tool_doc {
         $should_run: literal,
         $path: literal,
         $(rustc_tool = $rustc_tool:literal, )?
-        $(in_tree = $in_tree:literal, )?
-        [$($extra_arg: literal),+ $(,)?]
-        $(,)?
-    ) => {
+        $(in_tree = $in_tree:literal ,)?
+        $(is_library = $is_library:expr,)?
+        $(crates = $crates:expr)?
+       ) => {
         #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
         pub struct $tool {
             target: TargetSelection,
@@ -812,17 +821,6 @@ macro_rules! tool_doc {
                     SourceType::Submodule
                 };
 
-                // Symlink compiler docs to the output directory of rustdoc documentation.
-                let out_dirs = [
-                    builder.stage_out(compiler, Mode::ToolRustc).join(target.triple).join("doc"),
-                    // Cargo uses a different directory for proc macros.
-                    builder.stage_out(compiler, Mode::ToolRustc).join("doc"),
-                ];
-                for out_dir in out_dirs {
-                    t!(fs::create_dir_all(&out_dir));
-                    symlink_dir_force(&builder.config, &out, &out_dir);
-                }
-
                 // Build cargo command.
                 let mut cargo = prepare_tool_cargo(
                     builder,
@@ -839,9 +837,13 @@ macro_rules! tool_doc {
                 // Only include compiler crates, no dependencies of those, such as `libc`.
                 cargo.arg("--no-deps");
 
-                $(
-                    cargo.arg($extra_arg);
-                )+
+                if false $(|| $is_library)? {
+                    cargo.arg("--lib");
+                }
+
+                $(for krate in $crates {
+                    cargo.arg("-p").arg(krate);
+                })?
 
                 cargo.rustdocflag("--document-private-items");
                 // Since we always pass --document-private-items, there's no need to warn about linking to private items.
@@ -851,62 +853,69 @@ macro_rules! tool_doc {
                 cargo.rustdocflag("--generate-link-to-definition");
                 cargo.rustdocflag("-Zunstable-options");
 
+                let out_dir = builder.stage_out(compiler, Mode::ToolRustc).join(target.triple).join("doc");
+                $(for krate in $crates {
+                    let dir_name = krate.replace("-", "_");
+                    t!(fs::create_dir_all(out_dir.join(&*dir_name)));
+                })?
+
+                // Symlink compiler docs to the output directory of rustdoc documentation.
+                symlink_dir_force(&builder.config, &out, &out_dir);
+                let proc_macro_out_dir = builder.stage_out(compiler, Mode::ToolRustc).join("doc");
+                symlink_dir_force(&builder.config, &out, &proc_macro_out_dir);
+
                 let _guard = builder.msg_doc(compiler, stringify!($tool).to_lowercase(), target);
                 builder.run(&mut cargo.into());
+
+                if !builder.config.dry_run() {
+                    // Sanity check on linked doc directories
+                    $(for krate in $crates {
+                        let dir_name = krate.replace("-", "_");
+                        // Making sure the directory exists and is not empty.
+                        assert!(out.join(&*dir_name).read_dir().unwrap().next().is_some());
+                    })?
+                }
             }
         }
     }
 }
 
-tool_doc!(
-    Rustdoc,
-    "rustdoc-tool",
-    "src/tools/rustdoc",
-    ["-p", "rustdoc", "-p", "rustdoc-json-types"]
-);
+tool_doc!(Rustdoc, "rustdoc-tool", "src/tools/rustdoc", crates = ["rustdoc", "rustdoc-json-types"]);
 tool_doc!(
     Rustfmt,
     "rustfmt-nightly",
     "src/tools/rustfmt",
-    ["-p", "rustfmt-nightly", "-p", "rustfmt-config_proc_macro"],
+    crates = ["rustfmt-nightly", "rustfmt-config_proc_macro"]
 );
-tool_doc!(Clippy, "clippy", "src/tools/clippy", ["-p", "clippy_utils"]);
-tool_doc!(Miri, "miri", "src/tools/miri", ["-p", "miri"]);
+tool_doc!(Clippy, "clippy", "src/tools/clippy", crates = ["clippy_utils"]);
+tool_doc!(Miri, "miri", "src/tools/miri", crates = ["miri"]);
 tool_doc!(
     Cargo,
     "cargo",
     "src/tools/cargo",
     rustc_tool = false,
     in_tree = false,
-    [
-        "-p",
+    crates = [
         "cargo",
-        "-p",
         "cargo-platform",
-        "-p",
         "cargo-util",
-        "-p",
         "crates-io",
-        "-p",
         "cargo-test-macro",
-        "-p",
         "cargo-test-support",
-        "-p",
         "cargo-credential",
-        "-p",
         "mdman",
         // FIXME: this trips a license check in tidy.
-        // "-p",
         // "resolver-tests",
     ]
 );
-tool_doc!(Tidy, "tidy", "src/tools/tidy", rustc_tool = false, ["-p", "tidy"]);
+tool_doc!(Tidy, "tidy", "src/tools/tidy", rustc_tool = false, crates = ["tidy"]);
 tool_doc!(
     Bootstrap,
     "bootstrap",
     "src/bootstrap",
     rustc_tool = false,
-    ["--lib", "-p", "bootstrap"]
+    is_library = true,
+    crates = ["bootstrap"]
 );
 
 #[derive(Ord, PartialOrd, Debug, Copy, Clone, Hash, PartialEq, Eq)]
diff --git a/src/ci/docker/run.sh b/src/ci/docker/run.sh
index a2891ef9563..cedbc0390f8 100755
--- a/src/ci/docker/run.sh
+++ b/src/ci/docker/run.sh
@@ -302,6 +302,7 @@ docker \
   --env DIST_TRY_BUILD \
   --env PR_CI_JOB \
   --env OBJDIR_ON_HOST="$objdir" \
+  --env CODEGEN_BACKENDS \
   --init \
   --rm \
   rust-ci \