PR5684: Fix refacto, the backend consumer was copying the Diagnostic object,
which meant that hasErrorOccurred() checks to prevent codegen-on-invalid weren't
working.

llvm-svn: 90560
diff --git a/clang/lib/Frontend/Backend.cpp b/clang/lib/Frontend/Backend.cpp
index 0374b0c..5930b33 100644
--- a/clang/lib/Frontend/Backend.cpp
+++ b/clang/lib/Frontend/Backend.cpp
@@ -38,7 +38,7 @@
 
 namespace {
   class BackendConsumer : public ASTConsumer {
-    Diagnostic Diags;
+    Diagnostic &Diags;
     BackendAction Action;
     const CodeGenOptions &CodeGenOpts;
     const LangOptions &LangOpts;
@@ -66,8 +66,7 @@
 
     void CreatePasses();
 
-    /// AddEmitPasses - Add passes necessary to emit assembly or LLVM
-    /// IR.
+    /// AddEmitPasses - Add passes necessary to emit assembly or LLVM IR.
     ///
     /// \return True on success.
     bool AddEmitPasses();