From ba13b6ec6f919430412d99a3d50ff87042a787a7 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Mon, 29 Sep 2025 21:02:52 -0700
Subject: [PATCH] bootstrap: build bootstrap docs with in-tree rustdoc

All of the docs need to be built with the same rustdoc. Otherwise,
any change to the search index breaks everything, because the two
rustdocs don't agree on the format.
---
 src/bootstrap/src/core/build_steps/doc.rs | 21 +++++++++++----------
 src/bootstrap/src/core/builder/tests.rs   | 18 ++++++++++--------
 2 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/src/bootstrap/src/core/build_steps/doc.rs b/src/bootstrap/src/core/build_steps/doc.rs
index 7865b6856593..37462c63f1b0 100644
--- a/src/bootstrap/src/core/build_steps/doc.rs
+++ b/src/bootstrap/src/core/build_steps/doc.rs
@@ -1024,12 +1024,9 @@ macro_rules! tool_doc {
                         run.builder.ensure(Rustc::from_build_compiler(run.builder, compilers.build_compiler(), target));
                         compilers.build_compiler()
                     }
-                    Mode::ToolBootstrap => {
-                        // bootstrap/host tools should be documented with the stage 0 compiler
-                        prepare_doc_compiler(run.builder, run.builder.host_target, 1)
-                    }
                     Mode::ToolTarget => {
-                        // target tools should be documented with the in-tree compiler
+                        // when shipping multiple docs together in one folder,
+                        // they all need to use the same rustdoc version
                         prepare_doc_compiler(run.builder, run.builder.host_target, run.builder.top_stage)
                     }
                     _ => {
@@ -1132,7 +1129,11 @@ macro_rules! tool_doc {
 tool_doc!(
     BuildHelper,
     "src/build_helper",
-    mode = Mode::ToolBootstrap,
+    // ideally, this would use ToolBootstrap,
+    // but we distribute these docs together in the same folder
+    // as a bunch of stage1 tools, and you can't mix rustdoc versions
+    // because that breaks cross-crate data (particularly search)
+    mode = Mode::ToolTarget,
     is_library = true,
     crates = ["build_helper"]
 );
@@ -1175,25 +1176,25 @@ tool_doc!(
     // "specialization" feature in its build script when it detects a nightly toolchain.
     allow_features: "specialization"
 );
-tool_doc!(Tidy, "src/tools/tidy", mode = Mode::ToolBootstrap, crates = ["tidy"]);
+tool_doc!(Tidy, "src/tools/tidy", mode = Mode::ToolTarget, crates = ["tidy"]);
 tool_doc!(
     Bootstrap,
     "src/bootstrap",
-    mode = Mode::ToolBootstrap,
+    mode = Mode::ToolTarget,
     is_library = true,
     crates = ["bootstrap"]
 );
 tool_doc!(
     RunMakeSupport,
     "src/tools/run-make-support",
-    mode = Mode::ToolBootstrap,
+    mode = Mode::ToolTarget,
     is_library = true,
     crates = ["run_make_support"]
 );
 tool_doc!(
     Compiletest,
     "src/tools/compiletest",
-    mode = Mode::ToolBootstrap,
+    mode = Mode::ToolTarget,
     is_library = true,
     crates = ["compiletest"]
 );
diff --git a/src/bootstrap/src/core/builder/tests.rs b/src/bootstrap/src/core/builder/tests.rs
index 88df469e9a09..3306435758b4 100644
--- a/src/bootstrap/src/core/builder/tests.rs
+++ b/src/bootstrap/src/core/builder/tests.rs
@@ -1158,13 +1158,12 @@ mod snapshot {
         [doc] embedded-book (book) <host>
         [doc] edition-guide (book) <host>
         [doc] style-guide (book) <host>
-        [build] rustdoc 0 <host>
-        [doc] rustc 0 <host> -> Tidy 1 <host>
-        [doc] rustc 0 <host> -> Bootstrap 1 <host>
+        [doc] rustc 1 <host> -> Tidy 2 <host>
+        [doc] rustc 1 <host> -> Bootstrap 2 <host>
         [doc] rustc 1 <host> -> releases 2 <host>
-        [doc] rustc 0 <host> -> RunMakeSupport 1 <host>
-        [doc] rustc 0 <host> -> BuildHelper 1 <host>
-        [doc] rustc 0 <host> -> Compiletest 1 <host>
+        [doc] rustc 1 <host> -> RunMakeSupport 2 <host>
+        [doc] rustc 1 <host> -> BuildHelper 2 <host>
+        [doc] rustc 1 <host> -> Compiletest 2 <host>
         [build] rustc 0 <host> -> RustInstaller 1 <host>
         "
         );
@@ -2686,8 +2685,11 @@ mod snapshot {
                 .path("src/tools/compiletest")
                 .stage(2)
                 .render_steps(), @r"
-        [build] rustdoc 0 <host>
-        [doc] rustc 0 <host> -> Compiletest 1 <host>
+        [build] llvm <host>
+        [build] rustc 0 <host> -> rustc 1 <host>
+        [build] rustc 1 <host> -> std 1 <host>
+        [build] rustdoc 1 <host>
+        [doc] rustc 1 <host> -> Compiletest 2 <host>
         ");
     }