From 2cedd86b1c25db321e7e023f6a429e23425a7e00 Mon Sep 17 00:00:00 2001
From: Fabian Wolff <fabian.wolff@alumni.ethz.ch>
Date: Thu, 17 Jun 2021 16:45:26 +0200
Subject: [PATCH] Fix ICE when using `#[doc(keyword = "...")]` on non-items

---
 compiler/rustc_passes/src/check_attr.rs |  7 +++++--
 src/test/ui/rustdoc/issue-83512.rs      | 10 ++++++++++
 src/test/ui/rustdoc/issue-83512.stderr  |  8 ++++++++
 3 files changed, 23 insertions(+), 2 deletions(-)
 create mode 100644 src/test/ui/rustdoc/issue-83512.rs
 create mode 100644 src/test/ui/rustdoc/issue-83512.stderr

diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
index eca84c791fb3..e85392cf0bda 100644
--- a/compiler/rustc_passes/src/check_attr.rs
+++ b/compiler/rustc_passes/src/check_attr.rs
@@ -525,8 +525,11 @@ impl CheckAttrVisitor<'tcx> {
             self.doc_attr_str_error(meta, "keyword");
             return false;
         }
-        match self.tcx.hir().expect_item(hir_id).kind {
-            ItemKind::Mod(ref module) => {
+        match self.tcx.hir().find(hir_id).and_then(|node| match node {
+            hir::Node::Item(item) => Some(&item.kind),
+            _ => None,
+        }) {
+            Some(ItemKind::Mod(ref module)) => {
                 if !module.item_ids.is_empty() {
                     self.tcx
                         .sess
diff --git a/src/test/ui/rustdoc/issue-83512.rs b/src/test/ui/rustdoc/issue-83512.rs
new file mode 100644
index 000000000000..378f685ed30a
--- /dev/null
+++ b/src/test/ui/rustdoc/issue-83512.rs
@@ -0,0 +1,10 @@
+// Regression test for the ICE described in #83512.
+
+#![feature(doc_keyword)]
+#![crate_type="lib"]
+
+trait Foo {
+    #[doc(keyword = "match")]
+    //~^ ERROR: `#[doc(keyword = "...")]` can only be used on modules
+    fn quux() {}
+}
diff --git a/src/test/ui/rustdoc/issue-83512.stderr b/src/test/ui/rustdoc/issue-83512.stderr
new file mode 100644
index 000000000000..da7e480c63e3
--- /dev/null
+++ b/src/test/ui/rustdoc/issue-83512.stderr
@@ -0,0 +1,8 @@
+error: `#[doc(keyword = "...")]` can only be used on modules
+  --> $DIR/issue-83512.rs:7:11
+   |
+LL |     #[doc(keyword = "match")]
+   |           ^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+