PR15300: Support C++11 attributes on base-specifiers. We don't support any such

attributes yet, so just issue the appropriate diagnostics. Also generalize the
fixit for attributes-in-the-wrong-place code and reuse it here, if attributes
are placed after the access-specifier or 'virtual' in a base specifier.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175575 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 63 insertions, 27 deletions

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 0dd1e0a6f4..cc47ee1d90 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -1144,6 +1144,25 @@ bool Parser::DiagnoseProhibitedCXX11Attribute() {
   llvm_unreachable("All cases handled above.");
 }
 
+/// DiagnoseMisplacedCXX11Attribute - We have found the opening square brackets
+/// of a C++11 attribute-specifier in a location where an attribute is not
+/// permitted, but we know where the attributes ought to be written. Parse them
+/// anyway, and provide a fixit moving them to the right place.
+void Parser::DiagnoseMisplacedCXX11Attribute(ParsedAttributesWithRange &Attrs,
+                                             SourceLocation CorrectLocation) {
+  assert((Tok.is(tok::l_square) && NextToken().is(tok::l_square)) ||
+         Tok.is(tok::kw_alignas));
+
+  // Consume the attributes.
+  SourceLocation Loc = Tok.getLocation();
+  ParseCXX11Attributes(Attrs);
+  CharSourceRange AttrRange(SourceRange(Loc, Attrs.Range.getEnd()), true);
+
+  Diag(Loc, diag::err_attributes_not_allowed)
+    << FixItHint::CreateInsertionFromRange(CorrectLocation, AttrRange)
+    << FixItHint::CreateRemoval(AttrRange);
+}
+
 void Parser::DiagnoseProhibitedAttributes(ParsedAttributesWithRange &attrs) {
   Diag(attrs.Range.getBegin(), diag::err_attributes_not_allowed)
     << attrs.Range;
diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index 1a1eeb9402..4d428ceea1 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -802,15 +802,18 @@ void Parser::ParseUnderlyingTypeSpecifier(DeclSpec &DS) {
 /// class. The result is either a type or null, depending on whether a type 
 /// name was found.
 ///
-///       base-type-specifier: [C++ 10.1]
+///       base-type-specifier: [C++11 class.derived]
 ///         class-or-decltype
-///       class-or-decltype: [C++ 10.1]
+///       class-or-decltype: [C++11 class.derived]
 ///         nested-name-specifier[opt] class-name
 ///         decltype-specifier
-///       class-name: [C++ 9.1]
+///       class-name: [C++ class.name]
 ///         identifier
 ///         simple-template-id
 ///
+/// In C++98, instead of base-type-specifier, we have:
+///
+///         ::[opt] nested-name-specifier[opt] class-name
 Parser::TypeResult Parser::ParseBaseTypeSpecifier(SourceLocation &BaseLoc,
                                                   SourceLocation &EndLocation) {
   // Ignore attempts to use typename
@@ -1636,26 +1639,33 @@ void Parser::ParseBaseClause(Decl *ClassDecl) {
 /// 'public bar' and 'virtual private baz' are each base-specifiers.
 ///
 ///       base-specifier: [C++ class.derived]
-///         ::[opt] nested-name-specifier[opt] class-name
-///         'virtual' access-specifier[opt] ::[opt] nested-name-specifier[opt]
-///                        base-type-specifier
-///         access-specifier 'virtual'[opt] ::[opt] nested-name-specifier[opt]
-///                        base-type-specifier
+///         attribute-specifier-seq[opt] base-type-specifier
+///         attribute-specifier-seq[opt] 'virtual' access-specifier[opt]
+///                 base-type-specifier
+///         attribute-specifier-seq[opt] access-specifier 'virtual'[opt]
+///                 base-type-specifier
 Parser::BaseResult Parser::ParseBaseSpecifier(Decl *ClassDecl) {
   bool IsVirtual = false;
   SourceLocation StartLoc = Tok.getLocation();
 
+  ParsedAttributesWithRange Attributes(AttrFactory);
+  MaybeParseCXX11Attributes(Attributes);
+
   // Parse the 'virtual' keyword.
   if (Tok.is(tok::kw_virtual))  {
     ConsumeToken();
     IsVirtual = true;
   }
 
+  CheckMisplacedCXX11Attribute(Attributes, StartLoc);
+
   // Parse an (optional) access specifier.
   AccessSpecifier Access = getAccessSpecifierIfPresent();
   if (Access != AS_none)
     ConsumeToken();
 
+  CheckMisplacedCXX11Attribute(Attributes, StartLoc);
+
   // Parse the 'virtual' keyword (again!), in case it came after the
   // access specifier.
   if (Tok.is(tok::kw_virtual))  {
@@ -1669,6 +1679,8 @@ Parser::BaseResult Parser::ParseBaseSpecifier(Decl *ClassDecl) {
     IsVirtual = true;
   }
 
+  CheckMisplacedCXX11Attribute(Attributes, StartLoc);
+
   // Parse the class-name.
   SourceLocation EndLocation;
   SourceLocation BaseLoc;
@@ -1688,8 +1700,9 @@ Parser::BaseResult Parser::ParseBaseSpecifier(Decl *ClassDecl) {
 
   // Notify semantic analysis that we have parsed a complete
   // base-specifier.
-  return Actions.ActOnBaseSpecifier(ClassDecl, Range, IsVirtual, Access,
-                                    BaseType.get(), BaseLoc, EllipsisLoc);
+  return Actions.ActOnBaseSpecifier(ClassDecl, Range, Attributes, IsVirtual,
+                                    Access, BaseType.get(), BaseLoc,
+                                    EllipsisLoc);
 }
 
 /// getAccessSpecifierIfPresent - Determine whether the next token is
@@ -2384,7 +2397,7 @@ ExprResult Parser::ParseCXXMemberInitializer(Decl *D, bool IsFunction,
 ///
 void Parser::ParseCXXMemberSpecification(SourceLocation RecordLoc,
                                          SourceLocation AttrFixitLoc,
-                                         ParsedAttributes &Attrs,
+                                         ParsedAttributesWithRange &Attrs,
                                          unsigned TagType, Decl *TagDecl) {
   assert((TagType == DeclSpec::TST_struct ||
          TagType == DeclSpec::TST_interface ||
@@ -2457,20 +2470,7 @@ void Parser::ParseCXXMemberSpecification(SourceLocation RecordLoc,
     // These attributes are not allowed to appear here,
     // and the only possible place for them to appertain
     // to the class would be between class-key and class-name.
-    ParsedAttributesWithRange Attributes(AttrFactory);
-    MaybeParseCXX11Attributes(Attributes);
-    SourceRange AttrRange = Attributes.Range;
-    if (AttrRange.isValid()) {
-      Diag(AttrRange.getBegin(), diag::err_attributes_not_allowed)
-        << AttrRange
-        << FixItHint::CreateInsertionFromRange(AttrFixitLoc,
-                                               CharSourceRange(AttrRange, true))
-        << FixItHint::CreateRemoval(AttrRange);
-
-      // Recover by adding attributes to the attribute list of the class
-      // so they can be applied on the class later.
-      Attrs.takeAllFrom(Attributes);
-    }
+    CheckMisplacedCXX11Attribute(Attrs, AttrFixitLoc);
   }
 
   if (Tok.is(tok::colon)) {
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 1711c8726e..8b0ccd7146 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -1172,6 +1172,7 @@ Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
 /// 'public bar' and 'virtual private baz' are each base-specifiers.
 BaseResult
 Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
+                         ParsedAttributes &Attributes,
                          bool Virtual, AccessSpecifier Access,
                          ParsedType basetype, SourceLocation BaseLoc,
                          SourceLocation EllipsisLoc) {
@@ -1183,6 +1184,22 @@ Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
   if (!Class)
     return true;
 
+  // We do not support any C++11 attributes on base-specifiers yet.
+  // Diagnose any attributes we see.
+  if (!Attributes.empty()) {
+    for (AttributeList *Attr = Attributes.getList(); Attr;
+         Attr = Attr->getNext()) {
+      if (Attr->isInvalid() ||
+          Attr->getKind() == AttributeList::IgnoredAttribute)
+        continue;
+      Diag(Attr->getLoc(),
+           Attr->getKind() == AttributeList::UnknownAttribute
+             ? diag::warn_unknown_attribute_ignored
+             : diag::err_base_specifier_attribute)
+        << Attr->getName();
+    }
+  }
+
   TypeSourceInfo *TInfo = 0;
   GetTypeFromParser(basetype, &TInfo);
 
diff --git a/lib/Sema/SemaStmtAttr.cpp b/lib/Sema/SemaStmtAttr.cpp
index b268b4502c..eb0188a0db 100644
--- a/lib/Sema/SemaStmtAttr.cpp
+++ b/lib/Sema/SemaStmtAttr.cpp
@@ -58,8 +58,8 @@ static Attr *ProcessStmtAttribute(Sema &S, Stmt *St, const AttributeList &A,
   default:
     // if we're here, then we parsed a known attribute, but didn't recognize
     // it as a statement attribute => it is declaration attribute
-    S.Diag(A.getRange().getBegin(), diag::warn_attribute_invalid_on_stmt)
-        << A.getName()->getName() << St->getLocStart();
+    S.Diag(A.getRange().getBegin(), diag::err_attribute_invalid_on_stmt)
+        << A.getName() << St->getLocStart();
     return 0;
   }
 }