1 files changed, 3 insertions, 3 deletions
diff --git a/clang/lib/AST/NestedNameSpecifier.cpp b/clang/lib/AST/NestedNameSpecifier.cpp
index 09d85102585..137953fa820 100644
--- a/clang/lib/AST/NestedNameSpecifier.cpp
+++ b/clang/lib/AST/NestedNameSpecifier.cpp
@@ -472,7 +472,7 @@ TypeLoc NestedNameSpecifierLoc::getTypeLoc() const {
 }
 
 static void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
-              unsigned &BufferCapacity) {
+                   unsigned &BufferCapacity) {
   if (Start == End)
     return;
 
@@ -489,9 +489,9 @@ static void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
     Buffer = NewBuffer;
     BufferCapacity = NewCapacity;
   }
-
+  assert(Buffer && Start && End && End > Start && "Illegal memory buffer copy");
   memcpy(Buffer + BufferSize, Start, End - Start);
-  BufferSize += End-Start;
+  BufferSize += End - Start;
 }
 
 /// Save a source location to the given buffer.