objective-c modern translator: Correctly translate

nonfragile ivar access code when ivar type is a 
locally defined struct/union type. // rdar://11323187


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@155740 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Rewrite/RewriteModernObjC.cpp

@@ -7245,13 +7245,50 @@ Stmt *RewriteModernObjC::RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV) {
                                               SourceLocation(),
                                               addExpr);
       QualType IvarT = D->getType();
+
+      if (IvarT->isRecordType()) {
+        RecordDecl *RD = IvarT->getAs<RecordType>()->getDecl();
+        RD = RD->getDefinition();
+        bool structIsInside = RD &&
+          Context->getSourceManager().isBeforeInTranslationUnit(
+            iFaceDecl->getDecl()->getLocation(), RD->getLocation());
+        if (structIsInside) {
+          // decltype(((Foo_IMPL*)0)->bar) *
+          std::string RecName = iFaceDecl->getDecl()->getName();
+          RecName += "_IMPL";
+          RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
+                                              SourceLocation(), SourceLocation(),
+                                              &Context->Idents.get(RecName.c_str()));
+          QualType PtrStructIMPL = Context->getPointerType(Context->getTagDeclType(RD));
+          unsigned UnsignedIntSize = 
+            static_cast<unsigned>(Context->getTypeSize(Context->UnsignedIntTy));
+          Expr *Zero = IntegerLiteral::Create(*Context,
+                                              llvm::APInt(UnsignedIntSize, 0),
+                                              Context->UnsignedIntTy, SourceLocation());
+          Zero = NoTypeInfoCStyleCastExpr(Context, PtrStructIMPL, CK_BitCast, Zero);
+          ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
+                                                  Zero);
+          FieldDecl *FD = FieldDecl::Create(*Context, 0, SourceLocation(),
+                                            SourceLocation(),
+                                            &Context->Idents.get(D->getNameAsString()),
+                                            IvarT, 0,
+                                            /*BitWidth=*/0, /*Mutable=*/true,
+                                            /*HasInit=*/false);
+          MemberExpr *ME = new (Context) MemberExpr(PE, true, FD, SourceLocation(),
+                                                    FD->getType(), VK_LValue,
+                                                    OK_Ordinary);
+          IvarT = Context->getDecltypeType(ME, ME->getType());
+        }
+      }
       convertObjCTypeToCStyleType(IvarT);
       QualType castT = Context->getPointerType(IvarT);
-      
+          
       castExpr = NoTypeInfoCStyleCastExpr(Context, 
                                           castT,
                                           CK_BitCast,
                                           PE);
+      
+      
       Expr *Exp = new (Context) UnaryOperator(castExpr, UO_Deref, IvarT,
                                               VK_LValue, OK_Ordinary,
                                               SourceLocation());

test/Rewriter/rewrite-modern-struct-ivar.mm

@@ -1,7 +1,7 @@
 // RUN: %clang_cc1 -E %s -o %t.mm
 // RUN: %clang_cc1 -fblocks -rewrite-objc -fms-extensions %t.mm -o %t-rw.cpp 
 // RUN: FileCheck --input-file=%t-rw.cpp %s
-// RUN: %clang_cc1 -fsyntax-only -Wno-address-of-temporary -D"Class=void*" -D"id=void*" -D"SEL=void*" -D"__declspec(X)=" %t-rw.cpp
+// RUN: %clang_cc1 -fsyntax-only -Wno-address-of-temporary -Wno-c++11-narrowing -std=c++11 -D"Class=void*" -D"id=void*" -D"SEL=void*" -D"__declspec(X)=" %t-rw.cpp
 
 struct S {
     int i1;
@@ -20,5 +20,33 @@ struct S {
 @implementation I
 - (struct S) dMeth{ return struct_ivar; }
 @end
-  
+
 // CHECK: return (*(struct S *)((char *)self + OBJC_IVAR_$_I$struct_ivar));
+
+// rdar://11323187
+@interface Foo{
+    @protected 
+    struct {
+        int x:1;
+        int y:1;
+    } bar;
+
+    struct _S {
+        int x:1;
+        int y:1;
+    } s;
+
+}
+@end
+@implementation Foo
+- (void)x {
+  bar.x = 0;
+  bar.y = 1;
+
+  s.x = 0;
+  s.y = 1;
+}
+@end
+
+// CHECK: (*(decltype(((Foo_IMPL *)0U)->bar) *)((char *)self + OBJC_IVAR_$_Foo$bar)).x = 0;
+// CHECK:  (*(decltype(((Foo_IMPL *)0U)->s) *)((char *)self + OBJC_IVAR_$_Foo$s)).x = 0;