1 files changed, 15 insertions, 0 deletions
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 01aaf8be323..592956b9dbc 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -6588,6 +6588,21 @@ void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init,
 
     if (VDecl->hasAttr<BlocksAttr>())
       checkRetainCycles(VDecl, Init);
+
+    // It is safe to assign a weak reference into a strong variable.
+    // Although this code can still have problems:
+    //   id x = self.weakProp;
+    //   id y = self.weakProp;
+    // we do not warn to warn spuriously when 'x' and 'y' are on separate
+    // paths through the function. This should be revisited if
+    // -Wrepeated-use-of-weak is made flow-sensitive.
+    if (VDecl->getType().getObjCLifetime() == Qualifiers::OCL_Strong) {
+      DiagnosticsEngine::Level Level =
+        Diags.getDiagnosticLevel(diag::warn_arc_repeated_use_of_weak,
+                                 Init->getLocStart());
+      if (Level != DiagnosticsEngine::Ignored)
+        getCurFunction()->markSafeWeakUse(Init);
+    }
   }
 
   Init = MaybeCreateExprWithCleanups(Init);