Try to appease MSVC

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@118487 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/DocumentXML.cpp b/lib/Frontend/DocumentXML.cpp
index 75c1583..9ed10c8 100644
--- a/lib/Frontend/DocumentXML.cpp
+++ b/lib/Frontend/DocumentXML.cpp
@@ -105,7 +105,11 @@
       if (isprint(C))
         value += C;
       else {
+#ifdef LLVM_ON_WIN32
+        sprintf(buffer, "\\%03o", C);
+#else
         snprintf(buffer, sizeof(buffer), "\\%03o", C);
+#endif
         value += buffer;
       }
       break;