precompute the std crates before documenting for rust-docs-json

This fixes a regression from rust-lang#128182.

Signed-off-by: onur-ozkan <[email protected]>

Author: onur-ozkan

src/bootstrap/src/core/build_steps/dist.rs

@@ -103,10 +103,18 @@ impl Step for JsonDocs {
     /// Builds the `rust-docs-json` installer component.
     fn run(self, builder: &Builder<'_>) -> Option<GeneratedTarball> {
         let host = self.host;
-        builder.ensure(crate::core::build_steps::doc::Std::new(
+
+        let crates = builder
+            .in_tree_crates("sysroot", Some(host))
+            .into_iter()
+            .map(|krate| krate.name.to_string())
+            .collect();
+
+        builder.ensure(crate::core::build_steps::doc::Std::new_with_crates(
             builder.top_stage,
             host,
             DocumentationFormat::Json,
+            crates,
         ));
 
         let dest = "share/doc/rust/json";

src/bootstrap/src/core/build_steps/doc.rs

@@ -567,6 +567,15 @@ impl Std {
     pub(crate) fn new(stage: u32, target: TargetSelection, format: DocumentationFormat) -> Self {
         Std { stage, target, format, crates: vec![] }
     }
+
+    pub(crate) fn new_with_crates(
+        stage: u32,
+        target: TargetSelection,
+        format: DocumentationFormat,
+        crates: Vec<String>,
+    ) -> Self {
+        Std { stage, target, format, crates }
+    }
 }
 
 impl Step for Std {