Allow C++0x enumerations with a fixed underlying type in

Objective-C. The @encode'ing of such an enumeration type is the same
as its underlying type. <rdar://problem/5276348>.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@139297 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 19 insertions, 6 deletions

diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 3a3fba5d61..5fa6704dba 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -4204,6 +4204,17 @@ static char ObjCEncodingForPrimitiveKind(const ASTContext *C, QualType T) {
     }
 }
 
+static char ObjCEncodingForEnumType(const ASTContext *C, const EnumType *ET) {
+  EnumDecl *Enum = ET->getDecl();
+  
+  // The encoding of an non-fixed enum type is always 'i', regardless of size.
+  if (!Enum->isFixed())
+    return 'i';
+  
+  // The encoding of a fixed enum type matches its fixed underlying type.
+  return ObjCEncodingForPrimitiveKind(C, Enum->getIntegerType());
+}
+
 static void EncodeBitField(const ASTContext *Ctx, std::string& S,
                            QualType T, const FieldDecl *FD) {
   const Expr *E = FD->getBitWidth();
@@ -4228,8 +4239,8 @@ static void EncodeBitField(const ASTContext *Ctx, std::string& S,
     const RecordDecl *RD = FD->getParent();
     const ASTRecordLayout &RL = Ctx->getASTRecordLayout(RD);
     S += llvm::utostr(RL.getFieldOffset(FD->getFieldIndex()));
-    if (T->isEnumeralType())
-      S += 'i';
+    if (const EnumType *ET = T->getAs<EnumType>())
+      S += ObjCEncodingForEnumType(Ctx, ET);
     else
       S += ObjCEncodingForPrimitiveKind(Ctx, T);
   }
@@ -4415,11 +4426,11 @@ void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
     return;
   }
   
-  if (T->isEnumeralType()) {
+  if (const EnumType *ET = T->getAs<EnumType>()) {
     if (FD && FD->isBitField())
       EncodeBitField(this, S, T, FD);
     else
-      S += 'i';
+      S += ObjCEncodingForEnumType(this, ET);
     return;
   }
 
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 2bf172dec1..c7b00ea5c3 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -599,6 +599,7 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
            .Case("objc_arc", LangOpts.ObjCAutoRefCount)
            .Case("objc_arc_weak", LangOpts.ObjCAutoRefCount && 
                  LangOpts.ObjCRuntimeHasWeak)
+           .Case("objc_fixed_enum", LangOpts.ObjC2)
            .Case("objc_instancetype", LangOpts.ObjC2)
            .Case("objc_nonfragile_abi", LangOpts.ObjCNonFragileABI)
            .Case("objc_weak_class", LangOpts.ObjCNonFragileABI)
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 4928bde002..40674ee7a9 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -2555,7 +2555,8 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
   ParsedAttributes attrs(AttrFactory);
   MaybeParseGNUAttributes(attrs);
 
-  bool AllowFixedUnderlyingType = getLang().CPlusPlus0x || getLang().Microsoft;
+  bool AllowFixedUnderlyingType 
+    = getLang().CPlusPlus0x || getLang().Microsoft || getLang().ObjC2;
 
   CXXScopeSpec &SS = DS.getTypeSpecScope();
   if (getLang().CPlusPlus) {
@@ -2658,7 +2659,7 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
       SourceRange Range;
       BaseType = ParseTypeName(&Range);
       
-      if (!getLang().CPlusPlus0x)
+      if (!getLang().CPlusPlus0x && !getLang().ObjC2)
         Diag(StartLoc, diag::ext_ms_enum_fixed_underlying_type)
           << Range;
     }