[sema] Allow to opt-out of overriding the super class's designated initializers by marking the initializer as unavailable in the subclass.

rdar://20281322

llvm-svn: 243676

1 files changed, 10 insertions, 4 deletions

diff --git a/clang/lib/Sema/SemaObjCProperty.cpp b/clang/lib/Sema/SemaObjCProperty.cpp
index f139c83c734..02a0cdfee5f 100644
--- a/clang/lib/Sema/SemaObjCProperty.cpp
+++ b/clang/lib/Sema/SemaObjCProperty.cpp
@@ -1950,10 +1950,16 @@ void Sema::DiagnoseMissingDesignatedInitOverrides(
          I = DesignatedInits.begin(), E = DesignatedInits.end(); I != E; ++I) {
     const ObjCMethodDecl *MD = *I;
     if (!InitSelSet.count(MD->getSelector())) {
-      Diag(ImplD->getLocation(),
-           diag::warn_objc_implementation_missing_designated_init_override)
-        << MD->getSelector();
-      Diag(MD->getLocation(), diag::note_objc_designated_init_marked_here);
+      bool Ignore = false;
+      if (auto *IMD = IFD->getInstanceMethod(MD->getSelector())) {
+        Ignore = IMD->isUnavailable();
+      }
+      if (!Ignore) {
+        Diag(ImplD->getLocation(),
+             diag::warn_objc_implementation_missing_designated_init_override)
+          << MD->getSelector();
+        Diag(MD->getLocation(), diag::note_objc_designated_init_marked_here);
+      }
     }
   }
 }