[objc] Refactor and improve functionality for the -Wunused-property-ivar warning.

- Remove the additions to ObjCMethodDecl & ObjCIVarDecl that were getting de/serialized and consolidate
  all functionality for the checking for this warning in Sema::DiagnoseUnusedBackingIvarInAccessor
- Don't check immediately after the method body is finished, check when the @implementation is finished.
  This is so we can see if the ivar was referenced by any other method, even if the method was defined after the accessor.
- Don't silence the warning if any method is called from the accessor silence it if the accessor delegates to another method via self.

rdar://15727325

llvm-svn: 198432

1 files changed, 3 insertions, 5 deletions

diff --git a/clang/lib/AST/DeclObjC.cpp b/clang/lib/AST/DeclObjC.cpp
index 3db1acf0039..f6685de71aa 100644
--- a/clang/lib/AST/DeclObjC.cpp
+++ b/clang/lib/AST/DeclObjC.cpp
@@ -1440,8 +1440,7 @@ ObjCIvarDecl *ObjCIvarDecl::Create(ASTContext &C, ObjCContainerDecl *DC,
                                    SourceLocation IdLoc, IdentifierInfo *Id,
                                    QualType T, TypeSourceInfo *TInfo,
                                    AccessControl ac, Expr *BW,
-                                   bool synthesized,
-                                   bool backingIvarReferencedInAccessor) {
+                                   bool synthesized) {
   if (DC) {
     // Ivar's can only appear in interfaces, implementations (via synthesized
     // properties), and class extensions (via direct declaration, or synthesized
@@ -1469,13 +1468,12 @@ ObjCIvarDecl *ObjCIvarDecl::Create(ASTContext &C, ObjCContainerDecl *DC,
   }
 
   return new (C, DC) ObjCIvarDecl(DC, StartLoc, IdLoc, Id, T, TInfo, ac, BW,
-                                  synthesized, backingIvarReferencedInAccessor);
+                                  synthesized);
 }
 
 ObjCIvarDecl *ObjCIvarDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
   return new (C, ID) ObjCIvarDecl(0, SourceLocation(), SourceLocation(), 0,
-                                  QualType(), 0, ObjCIvarDecl::None, 0, false,
-                                  false);
+                                  QualType(), 0, ObjCIvarDecl::None, 0, false);
 }
 
 const ObjCInterfaceDecl *ObjCIvarDecl::getContainingInterface() const {