Added a new attribute, objc_root_class, which informs the compiler when a root class is intentionally declared.

The warning this inhibits, -Wobjc-root-class, is opt-in for now. However, all clang unit tests that would trigger
the warning have been updated to use -Wno-objc-root-class. <rdar://problem/7446698>


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154187 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 17 insertions, 1 deletions

diff --git a/include/clang/AST/NSAPI.h b/include/clang/AST/NSAPI.h
index 222c8dbacc..40e9759067 100644
--- a/include/clang/AST/NSAPI.h
+++ b/include/clang/AST/NSAPI.h
@@ -25,6 +25,7 @@ public:
   ASTContext &getASTContext() const { return Ctx; }
 
   enum NSClassIdKindKind {
+    ClassId_NSObject,
     ClassId_NSString,
     ClassId_NSArray,
     ClassId_NSMutableArray,
@@ -32,7 +33,7 @@ public:
     ClassId_NSMutableDictionary,
     ClassId_NSNumber
   };
-  static const unsigned NumClassIds = 6;
+  static const unsigned NumClassIds = 7;
 
   enum NSStringMethodKind {
     NSStr_stringWithString,
diff --git a/include/clang/Basic/Attr.td b/include/clang/Basic/Attr.td
index ee9f60f252..e8e0f35096 100644
--- a/include/clang/Basic/Attr.td
+++ b/include/clang/Basic/Attr.td
@@ -452,6 +452,11 @@ def ObjCReturnsInnerPointer : Attr {
   let Subjects = [ObjCMethod];
 }
 
+def ObjCRootClass : Attr {
+  let Spellings = ["objc_root_class"];
+  let Subjects = [ObjCInterface];
+}
+
 def Overloadable : Attr {
   let Spellings = ["overloadable"];
 }
@@ -534,10 +539,12 @@ def Unavailable : InheritableAttr {
 
 def ArcWeakrefUnavailable : InheritableAttr {
   let Spellings = ["objc_arc_weak_reference_unavailable"];
+  let Subjects = [ObjCInterface];
 }
 
 def ObjCRequiresPropertyDefs : InheritableAttr {
   let Spellings = ["objc_requires_property_definitions"];
+  let Subjects = [ObjCInterface];
 }
 
 def Unused : InheritableAttr {
diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index 2e91a5ffa8..c83985345b 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -148,6 +148,7 @@ def ObjCPropertyImpl : DiagGroup<"objc-property-implementation">;
 def ObjCMissingSuperCalls : DiagGroup<"objc-missing-super-calls">;
 def ObjCRetainBlockProperty : DiagGroup<"objc-noncopy-retain-block-property">;
 def ObjCReadonlyPropertyHasSetter : DiagGroup<"objc-readonly-with-setter-property">;
+def ObjCRootClass : DiagGroup<"objc-root-class">;
 def Packed : DiagGroup<"packed">;
 def Padded : DiagGroup<"padded">;
 def PointerArith : DiagGroup<"pointer-arith">;
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 30173fb7ba..515919c4fe 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -444,6 +444,13 @@ def note_receiver_is_id : Note<
   "receiver is treated with 'id' type for purpose of method lookup">;
 def note_suppressed_class_declare : Note<
   "class with specified objc_requires_property_definitions attribute is declared here">;
+def err_objc_root_class_subclass : Error<
+  "objc_root_class attribute may only be specified on a root class declaration">;
+def warn_objc_root_class_missing : Warning<
+	"class %0 defined without specifying a base class">,
+  InGroup<ObjCRootClass>, DefaultIgnore;
+def note_objc_needs_superclass : Note<
+  "add a super class to fix this problem">;
 def warn_dup_category_def : Warning<
   "duplicate definition of category %1 on interface %0">;
 def err_conflicting_super_class : Error<"conflicting super class name %0">;