-Wreceiver-is-weak: rephrase warning text and add a suggestion Note.

New output:
  warning: weak property may be unpredictably set to nil
  note: property declared here
  note: assign the value to a strong variable to keep the object alive
        during use

<rdar://problem/12277204>

llvm-svn: 164857

1 files changed, 14 insertions, 13 deletions

diff --git a/clang/lib/Sema/SemaExprObjC.cpp b/clang/lib/Sema/SemaExprObjC.cpp
index 58e28a94044..f3ae25ed482 100644
--- a/clang/lib/Sema/SemaExprObjC.cpp
+++ b/clang/lib/Sema/SemaExprObjC.cpp
@@ -1341,21 +1341,22 @@ static void DiagnoseARCUseOfWeakReceiver(Sema &S, Expr *Receiver) {
     }
   }
   
-  if (T.getObjCLifetime() == Qualifiers::OCL_Weak) {
-    S.Diag(Loc, diag::warn_receiver_is_weak) 
-      << ((!PDecl && !GDecl) ? 0 : (PDecl ? 1 : 2));
-    if (PDecl)
-      S.Diag(PDecl->getLocation(), diag::note_property_declare);
-    else if (GDecl)
-      S.Diag(GDecl->getLocation(), diag::note_method_declared_at) << GDecl;
-    return;
+  if (T.getObjCLifetime() != Qualifiers::OCL_Weak) {
+    if (!PDecl)
+      return;
+    if (!(PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_weak))
+      return;
   }
-  
-  if (PDecl && 
-      (PDecl->getPropertyAttributes() & ObjCPropertyDecl::OBJC_PR_weak)) {
-    S.Diag(Loc, diag::warn_receiver_is_weak) << 1;
+
+  S.Diag(Loc, diag::warn_receiver_is_weak)
+    << ((!PDecl && !GDecl) ? 0 : (PDecl ? 1 : 2));
+
+  if (PDecl)
     S.Diag(PDecl->getLocation(), diag::note_property_declare);
-  }
+  else if (GDecl)
+    S.Diag(GDecl->getLocation(), diag::note_method_declared_at) << GDecl;
+
+  S.Diag(Loc, diag::note_arc_assign_to_strong);
 }
 
 /// HandleExprPropertyRefExpr - Handle foo.bar where foo is a pointer to an