improve compatibility with GCC 4.4, patch by Michel Salim (PR3697)


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@65884 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index a8b09e5..6cb1908 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -18,6 +18,7 @@
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Lex/LexDiagnostic.h"
+#include <cstdio>
 #include <ctime>
 using namespace clang;