From 672edb0a04a5273e3a501f3b196844c125290780 Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Fri, 22 Feb 2013 09:15:49 +0000
Subject: [PATCH] Don't accidentally and silently accept C++11 attributes in
 decl-specifier-seqs in C++98.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175879 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Parse/ParseDecl.cpp    | 2 +-
 lib/Parse/ParseDeclCXX.cpp | 2 ++
 test/Parser/cxx-decl.cpp   | 3 +++
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 8ac3c504e2..6ab1540134 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -2197,7 +2197,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
 
     case tok::l_square:
     case tok::kw_alignas:
-      if (!isCXX11AttributeSpecifier())
+      if (!getLangOpts().CPlusPlus11 || !isCXX11AttributeSpecifier())
         goto DoneWithDeclSpec;
 
       ProhibitAttributes(attrs);
diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index 90926a362b..f040b9bfff 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -3186,6 +3186,8 @@ void Parser::ParseCXX11AttributeSpecifier(ParsedAttributes &attrs,
 ///       attribute-specifier-seq[opt] attribute-specifier
 void Parser::ParseCXX11Attributes(ParsedAttributesWithRange &attrs,
                                   SourceLocation *endLoc) {
+  assert(getLangOpts().CPlusPlus11);
+
   SourceLocation StartLoc = Tok.getLocation(), Loc;
   if (!endLoc)
     endLoc = &Loc;
diff --git a/test/Parser/cxx-decl.cpp b/test/Parser/cxx-decl.cpp
index 24ba127515..41d305b176 100644
--- a/test/Parser/cxx-decl.cpp
+++ b/test/Parser/cxx-decl.cpp
@@ -184,6 +184,9 @@ namespace PR15017 {
   template<typename T = struct X { int i; }> struct S {}; // expected-error {{'PR15017::X' can not be defined in a type specifier}}
 }
 
+// Ensure we produce at least some diagnostic for attributes in C++98.
+[[]] struct S; // expected-error 2{{}}
+
 // PR8380
 extern ""      // expected-error {{unknown linkage language}}
 test6a { ;// expected-error {{C++ requires a type specifier for all declarations}} \
-- 
2.40.0