1 files changed, 23 insertions, 15 deletions

diff --git a/clang/include/clang/Parse/Parser.h b/clang/include/clang/Parse/Parser.h
index 7a71ee3cb48..826114bc43d 100644
--- a/clang/include/clang/Parse/Parser.h
+++ b/clang/include/clang/Parse/Parser.h
@@ -2163,18 +2163,25 @@ public:
 private:
   void ParseBlockId(SourceLocation CaretLoc);
 
-  // Check for the start of a C++11 attribute-specifier-seq in a context where
-  // an attribute is not allowed.
+  /// Are [[]] attributes enabled?
+  bool standardAttributesAllowed() const {
+    const LangOptions &LO = getLangOpts();
+    return LO.DoubleSquareBracketAttributes;
+  }
+
+  // Check for the start of an attribute-specifier-seq in a context where an
+  // attribute is not allowed.
   bool CheckProhibitedCXX11Attribute() {
     assert(Tok.is(tok::l_square));
-    if (!getLangOpts().CPlusPlus11 || NextToken().isNot(tok::l_square))
+    if (!standardAttributesAllowed() || NextToken().isNot(tok::l_square))
       return false;
     return DiagnoseProhibitedCXX11Attribute();
   }
+
   bool DiagnoseProhibitedCXX11Attribute();
   void CheckMisplacedCXX11Attribute(ParsedAttributesWithRange &Attrs,
                                     SourceLocation CorrectLocation) {
-    if (!getLangOpts().CPlusPlus11)
+    if (!standardAttributesAllowed())
       return;
     if ((Tok.isNot(tok::l_square) || NextToken().isNot(tok::l_square)) &&
         Tok.isNot(tok::kw_alignas))
@@ -2194,17 +2201,18 @@ private:
   }
   void DiagnoseProhibitedAttributes(ParsedAttributesWithRange &attrs);
 
-  // Forbid C++11 attributes that appear on certain syntactic 
-  // locations which standard permits but we don't supported yet, 
-  // for example, attributes appertain to decl specifiers.
+  // Forbid C++11 and C2x attributes that appear on certain syntactic locations
+  // which standard permits but we don't supported yet, for example, attributes
+  // appertain to decl specifiers.
   void ProhibitCXX11Attributes(ParsedAttributesWithRange &Attrs,
                                unsigned DiagID);
 
-  /// \brief Skip C++11 attributes and return the end location of the last one.
+  /// \brief Skip C++11 and C2x attributes and return the end location of the
+  /// last one.
   /// \returns SourceLocation() if there are no attributes.
   SourceLocation SkipCXX11Attributes();
 
-  /// \brief Diagnose and skip C++11 attributes that appear in syntactic
+  /// \brief Diagnose and skip C++11 and C2x attributes that appear in syntactic
   /// locations where attributes are not allowed.
   void DiagnoseAndSkipCXX11Attributes();
 
@@ -2254,7 +2262,7 @@ private:
                           AttributeList::Syntax Syntax);
 
   void MaybeParseCXX11Attributes(Declarator &D) {
-    if (getLangOpts().CPlusPlus11 && isCXX11AttributeSpecifier()) {
+    if (standardAttributesAllowed() && isCXX11AttributeSpecifier()) {
       ParsedAttributesWithRange attrs(AttrFactory);
       SourceLocation endLoc;
       ParseCXX11Attributes(attrs, &endLoc);
@@ -2263,7 +2271,7 @@ private:
   }
   void MaybeParseCXX11Attributes(ParsedAttributes &attrs,
                                  SourceLocation *endLoc = nullptr) {
-    if (getLangOpts().CPlusPlus11 && isCXX11AttributeSpecifier()) {
+    if (standardAttributesAllowed() && isCXX11AttributeSpecifier()) {
       ParsedAttributesWithRange attrsWithRange(AttrFactory);
       ParseCXX11Attributes(attrsWithRange, endLoc);
       attrs.takeAllFrom(attrsWithRange);
@@ -2272,8 +2280,8 @@ private:
   void MaybeParseCXX11Attributes(ParsedAttributesWithRange &attrs,
                                  SourceLocation *endLoc = nullptr,
                                  bool OuterMightBeMessageSend = false) {
-    if (getLangOpts().CPlusPlus11 &&
-        isCXX11AttributeSpecifier(false, OuterMightBeMessageSend))
+    if (standardAttributesAllowed() &&
+      isCXX11AttributeSpecifier(false, OuterMightBeMessageSend))
       ParseCXX11Attributes(attrs, endLoc);
   }
 
@@ -2281,8 +2289,8 @@ private:
                                     SourceLocation *EndLoc = nullptr);
   void ParseCXX11Attributes(ParsedAttributesWithRange &attrs,
                             SourceLocation *EndLoc = nullptr);
-  /// \brief Parses a C++-style attribute argument list. Returns true if this
-  /// results in adding an attribute to the ParsedAttributes list.
+  /// \brief Parses a C++11 (or C2x)-style attribute argument list. Returns true
+  /// if this results in adding an attribute to the ParsedAttributes list.
   bool ParseCXX11AttributeArgs(IdentifierInfo *AttrName,
                                SourceLocation AttrNameLoc,
                                ParsedAttributes &Attrs, SourceLocation *EndLoc,