6 files changed, 27 insertions, 39 deletions
diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index 5974cd878dd..6d05ac073cc 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -317,10 +317,10 @@ fn merge_attrs(
             } else {
                 Attributes::from_ast(&both, None)
             },
-            both.cfg(cx.sess().diagnostic()),
+            both.cfg(cx.sess()),
         )
     } else {
-        (old_attrs.clean(cx), old_attrs.cfg(cx.sess().diagnostic()))
+        (old_attrs.clean(cx), old_attrs.cfg(cx.sess()))
     }
 }
 
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 411cfab9f06..e1dde8eeaf8 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -2018,7 +2018,7 @@ fn clean_extern_crate(
         def_id: crate_def_id.into(),
         visibility: krate.vis.clean(cx),
         kind: box ExternCrateItem { src: orig_name },
-        cfg: attrs.cfg(cx.sess().diagnostic()),
+        cfg: attrs.cfg(cx.sess()),
     }]
 }
 
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
index 47dae63f1fd..9861e838e33 100644
--- a/src/librustdoc/clean/types.rs
+++ b/src/librustdoc/clean/types.rs
@@ -444,7 +444,7 @@ impl Item {
             kind,
             box ast_attrs.clean(cx),
             cx,
-            ast_attrs.cfg(cx.sess().diagnostic()),
+            ast_attrs.cfg(cx.sess()),
         )
     }
 
@@ -456,7 +456,7 @@ impl Item {
         cx: &mut DocContext<'_>,
         cfg: Option<Arc<Cfg>>,
     ) -> Item {
-        debug!("name={:?}, def_id={:?}", name, def_id);
+        trace!("name={:?}, def_id={:?}", name, def_id);
 
         Item {
             def_id: def_id.into(),
@@ -795,7 +795,7 @@ crate trait AttributesExt {
 
     fn other_attrs(&self) -> Vec<ast::Attribute>;
 
-    fn cfg(&self, diagnostic: &::rustc_errors::Handler) -> Option<Arc<Cfg>>;
+    fn cfg(&self, sess: &Session) -> Option<Arc<Cfg>>;
 }
 
 impl AttributesExt for [ast::Attribute] {
@@ -820,17 +820,28 @@ impl AttributesExt for [ast::Attribute] {
         self.iter().filter(|attr| attr.doc_str().is_none()).cloned().collect()
     }
 
-    fn cfg(&self, diagnostic: &::rustc_errors::Handler) -> Option<Arc<Cfg>> {
+    fn cfg(&self, sess: &Session) -> Option<Arc<Cfg>> {
         let mut cfg = Cfg::True;
 
         for attr in self.iter() {
+            // #[doc]
             if attr.doc_str().is_none() && attr.has_name(sym::doc) {
-                if let Some(mi) = attr.meta() {
-                    if let Some(cfg_mi) = Attributes::extract_cfg(&mi) {
-                        // Extracted #[doc(cfg(...))]
-                        match Cfg::parse(cfg_mi) {
-                            Ok(new_cfg) => cfg &= new_cfg,
-                            Err(e) => diagnostic.span_err(e.span, e.msg),
+                // #[doc(...)]
+                if let Some(list) = attr.meta().as_ref().and_then(|mi| mi.meta_item_list()) {
+                    for item in list {
+                        // #[doc(include)]
+                        if !item.has_name(sym::cfg) {
+                            continue;
+                        }
+                        // #[doc(cfg(...))]
+                        if let Some(cfg_mi) = item
+                            .meta_item()
+                            .and_then(|item| rustc_expand::config::parse_cfg(&item, sess))
+                        {
+                            match Cfg::parse(&cfg_mi) {
+                                Ok(new_cfg) => cfg &= new_cfg,
+                                Err(e) => sess.span_err(e.span, e.msg),
+                            }
                         }
                     }
                 }
@@ -997,29 +1008,6 @@ impl Attributes {
         self.other_attrs.lists(name)
     }
 
-    /// Extracts the content from an attribute `#[doc(cfg(content))]`.
-    crate fn extract_cfg(mi: &ast::MetaItem) -> Option<&ast::MetaItem> {
-        use rustc_ast::NestedMetaItem::MetaItem;
-
-        if let ast::MetaItemKind::List(ref nmis) = mi.kind {
-            if nmis.len() == 1 {
-                if let MetaItem(ref cfg_mi) = nmis[0] {
-                    if cfg_mi.has_name(sym::cfg) {
-                        if let ast::MetaItemKind::List(ref cfg_nmis) = cfg_mi.kind {
-                            if cfg_nmis.len() == 1 {
-                                if let MetaItem(ref content_mi) = cfg_nmis[0] {
-                                    return Some(content_mi);
-                                }
-                            }
-                        }
-                    }
-                }
-            }
-        }
-
-        None
-    }
-
     /// Reads a `MetaItem` from within an attribute, looks for whether it is a
     /// `#[doc(include="file")]`, and returns the filename and contents of the file as loaded from
     /// its expansion.
diff --git a/src/librustdoc/doctest.rs b/src/librustdoc/doctest.rs
index c0157121e19..e563889f776 100644
--- a/src/librustdoc/doctest.rs
+++ b/src/librustdoc/doctest.rs
@@ -1096,7 +1096,7 @@ impl<'a, 'hir, 'tcx> HirCollector<'a, 'hir, 'tcx> {
         let ast_attrs = self.tcx.hir().attrs(hir_id);
         let mut attrs = Attributes::from_ast(ast_attrs, None);
 
-        if let Some(ref cfg) = ast_attrs.cfg(self.sess.diagnostic()) {
+        if let Some(ref cfg) = ast_attrs.cfg(self.sess) {
             if !cfg.matches(&self.sess.parse_sess, Some(&self.sess.features_untracked())) {
                 return;
             }
diff --git a/src/librustdoc/html/render/context.rs b/src/librustdoc/html/render/context.rs
index 2f3f87215c3..e0c1fd06e7b 100644
--- a/src/librustdoc/html/render/context.rs
+++ b/src/librustdoc/html/render/context.rs
@@ -155,7 +155,7 @@ impl<'tcx> Context<'tcx> {
         &self.cache
     }
 
-    fn sess(&self) -> &'tcx Session {
+    pub(super) fn sess(&self) -> &'tcx Session {
         &self.shared.tcx.sess
     }
 
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index 70b5458ece8..9d4ac3cf015 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -296,7 +296,7 @@ fn item_module(w: &mut Buffer, cx: &Context<'_>, item: &clean::Item, items: &[cl
                     let import_item = clean::Item {
                         def_id: import_def_id.into(),
                         attrs: import_attrs,
-                        cfg: ast_attrs.cfg(cx.tcx().sess.diagnostic()),
+                        cfg: ast_attrs.cfg(cx.sess()),
                         ..myitem.clone()
                     };