Make format string 64 bit safe.

llvm-svn: 143870
diff --git a/clang/lib/AST/VTableBuilder.cpp b/clang/lib/AST/VTableBuilder.cpp
index 7765817..f819f67 100644
--- a/clang/lib/AST/VTableBuilder.cpp
+++ b/clang/lib/AST/VTableBuilder.cpp
@@ -2136,7 +2136,7 @@
       uint64_t VTableIndex = I->first;
       const std::string &MethodName = I->second;
 
-      Out << llvm::format(" %4u | ", VTableIndex) << MethodName << '\n';
+      Out << llvm::format(" %4"PRIu64" | ", VTableIndex) << MethodName << '\n';
     }
   }