Objective-C: Issue warning in couple of obscure cases

when property autosynthesis does not synthesize a property.
When property is declared 'readonly' in a super class and
is redeclared 'readwrite' in a subclass. When a property
autosynthesis causes it to share 'ivar' with another property.
// rdar://13388503


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176889 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 21 insertions, 3 deletions

diff --git a/lib/Sema/SemaObjCProperty.cpp b/lib/Sema/SemaObjCProperty.cpp
index e046faa04d..2195541cd7 100644
--- a/lib/Sema/SemaObjCProperty.cpp
+++ b/lib/Sema/SemaObjCProperty.cpp
@@ -1585,13 +1585,31 @@ void Sema::DefaultSynthesizeProperties(Scope *S, ObjCImplDecl* IMPDecl,
   for (unsigned i = 0, e = PropertyOrder.size(); i != e; i++) {
     ObjCPropertyDecl *Prop = PropertyOrder[i];
     // If property to be implemented in the super class, ignore.
-    if (SuperPropMap[Prop->getIdentifier()])
+    if (SuperPropMap[Prop->getIdentifier()]) {
+      ObjCPropertyDecl *PropInSuperClass = SuperPropMap[Prop->getIdentifier()];
+      if ((Prop->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_readwrite) &&
+          (PropInSuperClass->getPropertyAttributes() &
+           ObjCPropertyDecl::OBJC_PR_readonly)) {
+            Diag(Prop->getLocation(), diag::warn_no_autosynthesis_property)
+              << Prop->getIdentifier()->getName();
+            Diag(PropInSuperClass->getLocation(), diag::note_property_declare);
+      }
       continue;
+    }
     // Is there a matching property synthesize/dynamic?
     if (Prop->isInvalidDecl() ||
-        Prop->getPropertyImplementation() == ObjCPropertyDecl::Optional ||
-        IMPDecl->FindPropertyImplIvarDecl(Prop->getIdentifier()))
+        Prop->getPropertyImplementation() == ObjCPropertyDecl::Optional)
       continue;
+    if (ObjCPropertyImplDecl *PID =
+          IMPDecl->FindPropertyImplIvarDecl(Prop->getIdentifier())) {
+      if (PID->getPropertyDecl() != Prop) {
+        Diag(Prop->getLocation(), diag::warn_no_autosynthesis_shared_ivar_property)
+          << Prop->getIdentifier()->getName();
+        if (!PID->getLocation().isInvalid())
+          Diag(PID->getLocation(), diag::note_property_synthesize);
+      }
+      continue;
+    }
     // Property may have been synthesized by user.
     if (IMPDecl->FindPropertyImplDecl(Prop->getIdentifier()))
       continue;