Accept unsugared docs in missing-doc lint

Closes #10853

src/librustc/middle/lint.rs

@@ -1074,7 +1074,13 @@ fn check_missing_doc_attrs(cx: &Context,
         _ => ()
     }
 
-    if !attrs.iter().any(|a| a.node.is_sugared_doc) {
+    let has_doc = attrs.iter().any(|a| {
+        match a.node.value.node {
+            ast::MetaNameValue(ref name, _) if "doc" == *name => true,
+            _ => false
+        }
+    });
+    if !has_doc {
         cx.span_lint(missing_doc, sp,
                      format!("missing documentation for {}", desc));
     }

src/test/run-pass/issue-10853.rs

@@ -0,0 +1,22 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[deny(missing_doc)];
+#[doc="module"];
+
+#[doc="struct"]
+pub struct Foo;
+
+pub fn foo() {
+    #[doc="fn"];
+}
+
+#[doc="main"]
+pub fn main() {}