diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -2472,10 +2472,13 @@
 
     for (auto Line : DeletedLines) {
       FormatToken *Tok = AnnotatedLines[Line]->First;
+      LLVM_DEBUG(llvm::dbgs() << "clean empty namespace:\"");
       while (Tok) {
+        LLVM_DEBUG(llvm::dbgs() << Tok->TokenText << " ");
         deleteToken(Tok);
         Tok = Tok->Next;
       }
+      LLVM_DEBUG(llvm::dbgs() << "\"\n");
     }
   }