fix an uninitialized variable, patch by Michael Spencer!

llvm-svn: 106025
diff --git a/clang/lib/Frontend/PrintPreprocessedOutput.cpp b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
index 80e697d..b5bbd52 100644
--- a/clang/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -394,6 +394,8 @@
   char Buffer[256];
   Token PrevPrevTok;
   Token PrevTok;
+  PrevPrevTok.setKind(tok::unknown);
+  PrevTok.setKind(tok::unknown);
   while (1) {
 
     // If this token is at the start of a line, emit newlines if needed.