Silence GCC warnings, RefCountedBase is meant to be default-initialized here.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@145396 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index a687937..4977b4f 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -38,7 +38,8 @@
   : LangOpts(new LangOptions()) {}
 
 CompilerInvocationBase::CompilerInvocationBase(const CompilerInvocationBase &X)
-  : LangOpts(new LangOptions(*X.getLangOpts())) {}
+  : llvm::RefCountedBase<CompilerInvocation>(),
+    LangOpts(new LangOptions(*X.getLangOpts())) {}
 
 //===----------------------------------------------------------------------===//
 // Utility functions.