diff --git a/lib/CodeGen/DwarfWriter.cpp b/lib/CodeGen/DwarfWriter.cpp
index 5b5be54..1505535 100644
--- a/lib/CodeGen/DwarfWriter.cpp
+++ b/lib/CodeGen/DwarfWriter.cpp
@@ -942,7 +942,7 @@
 
 //===----------------------------------------------------------------------===//
 
-/// DWContext
+/// DwarfWriter
 
 //===----------------------------------------------------------------------===//
 
@@ -1103,9 +1103,9 @@
       case '\t': O << "\\t"; break;
       default:
         O << '\\';
-        O << char('0' + (C >> 6));
-        O << char('0' + (C >> 3));
-        O << char('0' + (C >> 0));
+        O << char('0' + ((C >> 6) & 7));
+        O << char('0' + ((C >> 3) & 7));
+        O << char('0' + ((C >> 0) & 7));
         break;
       }
     } else if (C == '\"') {