Do not do the block-specific rewrite when there is no block literals.
Fixes radar 7546096.

llvm-svn: 93519
diff --git a/clang/lib/Frontend/RewriteObjC.cpp b/clang/lib/Frontend/RewriteObjC.cpp
index fc9401d..386d9b0 100644
--- a/clang/lib/Frontend/RewriteObjC.cpp
+++ b/clang/lib/Frontend/RewriteObjC.cpp
@@ -4043,7 +4043,7 @@
 void RewriteObjC::SynthesizeBlockLiterals(SourceLocation FunLocStart,
                                           const char *FunName) {
   // Insert declaration for the function in which block literal is used.
-  if (CurFunctionDeclToDeclareForBlock)
+  if (CurFunctionDeclToDeclareForBlock && !Blocks.empty())
     RewriteBlockLiteralFunctionDecl(CurFunctionDeclToDeclareForBlock);
   // Insert closures that were part of the function.
   for (unsigned i = 0; i < Blocks.size(); i++) {