2 files changed, 22 insertions, 0 deletions
diff --git a/clang/lib/Rewrite/RewriteModernObjC.cpp b/clang/lib/Rewrite/RewriteModernObjC.cpp
index fd433f88c2e..fd621a2a5cc 100644
--- a/clang/lib/Rewrite/RewriteModernObjC.cpp
+++ b/clang/lib/Rewrite/RewriteModernObjC.cpp
@@ -4812,6 +4812,10 @@ void RewriteModernObjC::RewriteByRefVar(VarDecl *ND) {
   // {0, &ND, some_flag, __size=sizeof(struct __Block_byref_ND), 
   //  initializer-if-any};
   bool hasInit = (ND->getInit() != 0);
+  // FIXME. rewriter does not support __block c++ objects which
+  // require construction.
+  if (hasInit && dyn_cast<CXXConstructExpr>(ND->getInit()))
+    hasInit = false;
   unsigned flags = 0;
   if (HasCopyAndDispose)
     flags |= BLOCK_HAS_COPY_DISPOSE;
diff --git a/clang/test/Rewriter/rewrite-modern-block.mm b/clang/test/Rewriter/rewrite-modern-block.mm
new file mode 100644
index 00000000000..c5231bfcebc
--- /dev/null
+++ b/clang/test/Rewriter/rewrite-modern-block.mm
@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -x objective-c++ -fblocks -fms-extensions -rewrite-objc %s -o %t-rw.cpp
+// RUN: %clang_cc1 -fsyntax-only -fblocks -Wno-address-of-temporary -D"Class=void*" -D"id=void*" -D"SEL=void*" -D"__declspec(X)=" %t-rw.cpp
+// rdar://11230308
+
+typedef struct {
+    char byte0;
+    char byte1;
+} CFUUIDBytes;
+
+void x(void *);
+
+void y() {
+    __block CFUUIDBytes bytes;
+    
+    void (^bar)() = ^{
+        x(&bytes);
+    };
+}