From 73efff4c8dc5824bc42010f551b3fc5e5678ad96 Mon Sep 17 00:00:00 2001
From: binarycat <binarycat@envs.net>
Date: Fri, 11 Jul 2025 13:45:51 -0500
Subject: [PATCH 1/2] add regression test for RUST-143222

---
 .../reexport/auxiliary/wrap-unnamable-type.rs        | 12 ++++++++++++
 .../rustdoc/reexport/wrapped-unnamble-type-143222.rs | 12 ++++++++++++
 2 files changed, 24 insertions(+)
 create mode 100644 tests/rustdoc/reexport/auxiliary/wrap-unnamable-type.rs
 create mode 100644 tests/rustdoc/reexport/wrapped-unnamble-type-143222.rs

diff --git a/tests/rustdoc/reexport/auxiliary/wrap-unnamable-type.rs b/tests/rustdoc/reexport/auxiliary/wrap-unnamable-type.rs
new file mode 100644
index 0000000000000..8ce0a0de54484
--- /dev/null
+++ b/tests/rustdoc/reexport/auxiliary/wrap-unnamable-type.rs
@@ -0,0 +1,12 @@
+pub trait Assoc {
+    type Ty;
+}
+
+pub struct Foo(<Foo as crate::Assoc>::Ty);
+
+const _: () = {
+    impl crate::Assoc for Foo {
+        type Ty = Bar;
+    }
+    pub struct Bar;
+};
diff --git a/tests/rustdoc/reexport/wrapped-unnamble-type-143222.rs b/tests/rustdoc/reexport/wrapped-unnamble-type-143222.rs
new file mode 100644
index 0000000000000..005a5c0b98add
--- /dev/null
+++ b/tests/rustdoc/reexport/wrapped-unnamble-type-143222.rs
@@ -0,0 +1,12 @@
+//@ compile-flags: -Z normalize-docs --document-private-items -Zunstable-options --show-type-layout
+//@ aux-build:wrap-unnamable-type.rs
+//@ build-aux-docs
+
+#![crate_name = "foo"]
+
+extern crate wrap_unnamable_type as helper;
+//extern crate helper;
+//@ has 'foo/struct.Foo.html'
+//@ !hasraw - '_/struct.Bar.html'
+#[doc(inline)]
+pub use helper::Foo;

From 950634d90cead84cbb19d3d05a51fe810d56bde6 Mon Sep 17 00:00:00 2001
From: binarycat <binarycat@envs.net>
Date: Sat, 12 Jul 2025 15:05:30 -0500
Subject: [PATCH 2/2] rustdoc: never try to link to unnamable types

---
 src/librustdoc/html/format.rs | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/librustdoc/html/format.rs b/src/librustdoc/html/format.rs
index bcb3e57c84428..aff6a4ddabae8 100644
--- a/src/librustdoc/html/format.rs
+++ b/src/librustdoc/html/format.rs
@@ -367,6 +367,8 @@ pub(crate) enum HrefError {
     Private,
     // Not in external cache, href link should be in same page
     NotInExternalCache,
+    /// Refers to an unnamable item, such as one defined within a function or const block.
+    UnnamableItem,
 }
 
 // Panics if `syms` is empty.
@@ -509,7 +511,13 @@ fn url_parts(
             builder.extend(module_fqp.iter().copied());
             Ok(builder)
         }
-        ExternalLocation::Local => Ok(href_relative_parts(module_fqp, relative_to)),
+        ExternalLocation::Local => {
+            if module_fqp.iter().any(|sym| sym.as_str() == "_") {
+                Err(HrefError::UnnamableItem)
+            } else {
+                Ok(href_relative_parts(module_fqp, relative_to))
+            }
+        }
         ExternalLocation::Unknown => Err(HrefError::DocumentationNotBuilt),
     }
 }