From 14ed92c33f2505241001e06c6d34f1c7d538fb66 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume.gomez@huawei.com>
Date: Mon, 26 Jun 2023 13:47:19 +0200
Subject: [PATCH] Don't merge cfg and doc(cfg) attributes for re-exports

---
 src/librustdoc/clean/mod.rs              | 74 +++++++++++++-----------
 src/librustdoc/html/render/print_item.rs | 13 +----
 2 files changed, 42 insertions(+), 45 deletions(-)

diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index dc9098d3ade7..6619288f9cb4 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -2648,6 +2648,38 @@ fn filter_tokens_from_list(
     tokens
 }
 
+fn filter_doc_attr_ident(ident: Symbol, is_inline: bool) -> bool {
+    if is_inline {
+        ident == sym::hidden || ident == sym::inline || ident == sym::no_inline
+    } else {
+        ident == sym::cfg
+    }
+}
+
+fn filter_doc_attr(normal: &mut ast::NormalAttr, is_inline: bool) {
+    match normal.item.args {
+        ast::AttrArgs::Delimited(ref mut args) => {
+            let tokens = filter_tokens_from_list(&args.tokens, |token| {
+                !matches!(
+                    token,
+                    TokenTree::Token(
+                        Token {
+                            kind: TokenKind::Ident(
+                                ident,
+                                _,
+                            ),
+                            ..
+                        },
+                        _,
+                    ) if filter_doc_attr_ident(*ident, is_inline),
+                )
+            });
+            args.tokens = TokenStream::new(tokens);
+        }
+        ast::AttrArgs::Empty | ast::AttrArgs::Eq(..) => {}
+    }
+}
+
 /// When inlining items, we merge their attributes (and all the reexports attributes too) with the
 /// final reexport. For example:
 ///
@@ -2674,13 +2706,6 @@ fn add_without_unwanted_attributes<'hir>(
     is_inline: bool,
     import_parent: Option<DefId>,
 ) {
-    // If it's not `#[doc(inline)]`, we don't want all attributes, otherwise we keep everything.
-    if !is_inline {
-        for attr in new_attrs {
-            attrs.push((Cow::Borrowed(attr), import_parent));
-        }
-        return;
-    }
     for attr in new_attrs {
         if matches!(attr.kind, ast::AttrKind::DocComment(..)) {
             attrs.push((Cow::Borrowed(attr), import_parent));
@@ -2689,33 +2714,14 @@ fn add_without_unwanted_attributes<'hir>(
         let mut attr = attr.clone();
         match attr.kind {
             ast::AttrKind::Normal(ref mut normal) => {
-                if let [ident] = &*normal.item.path.segments
-                    && let ident = ident.ident.name
-                    && ident == sym::doc
-                {
-                    match normal.item.args {
-                        ast::AttrArgs::Delimited(ref mut args) => {
-                            let tokens = filter_tokens_from_list(&args.tokens, |token| {
-                                !matches!(
-                                    token,
-                                    TokenTree::Token(
-                                        Token {
-                                            kind: TokenKind::Ident(
-                                                sym::hidden | sym::inline | sym::no_inline,
-                                                _,
-                                            ),
-                                            ..
-                                        },
-                                        _,
-                                    ),
-                                )
-                            });
-                            args.tokens = TokenStream::new(tokens);
-                            attrs.push((Cow::Owned(attr), import_parent));
-                        }
-                        ast::AttrArgs::Empty | ast::AttrArgs::Eq(..) => {
-                            attrs.push((Cow::Owned(attr), import_parent));
-                        }
+                if let [ident] = &*normal.item.path.segments {
+                    let ident = ident.ident.name;
+                    if ident == sym::doc {
+                        filter_doc_attr(normal, is_inline);
+                        attrs.push((Cow::Owned(attr), import_parent));
+                    } else if ident != sym::cfg {
+                        // If it's not a `cfg()` attribute, we keep it.
+                        attrs.push((Cow::Owned(attr), import_parent));
                     }
                 }
             }
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index 8fdbef65135c..8e009ba2294a 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -1,5 +1,3 @@
-use clean::AttributesExt;
-
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
@@ -464,16 +462,9 @@ fn item_module(w: &mut Buffer, cx: &mut Context<'_>, item: &clean::Item, items:
 
             clean::ImportItem(ref import) => {
                 let stab_tags = if let Some(import_def_id) = import.source.did {
-                    let ast_attrs = tcx.get_attrs_unchecked(import_def_id);
-                    let import_attrs = Box::new(clean::Attributes::from_ast(ast_attrs));
-
                     // Just need an item with the correct def_id and attrs
-                    let import_item = clean::Item {
-                        item_id: import_def_id.into(),
-                        attrs: import_attrs,
-                        cfg: ast_attrs.cfg(tcx, &cx.cache().hidden_cfg),
-                        ..myitem.clone()
-                    };
+                    let import_item =
+                        clean::Item { item_id: import_def_id.into(), ..myitem.clone() };
 
                     let stab_tags = Some(extra_info_tags(&import_item, item, tcx).to_string());
                     stab_tags