diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -195,11 +195,13 @@
   static void
   enumeration(IO &IO,
               FormatStyle::BraceWrappingAfterControlStatementStyle &Value) {
-    IO.enumCase(Value, "false", FormatStyle::BWACS_Never);
-    IO.enumCase(Value, "true", FormatStyle::BWACS_Always);
     IO.enumCase(Value, "Never", FormatStyle::BWACS_Never);
     IO.enumCase(Value, "MultiLine", FormatStyle::BWACS_MultiLine);
     IO.enumCase(Value, "Always", FormatStyle::BWACS_Always);
+
+    // For backward compatibility.
+    IO.enumCase(Value, "false", FormatStyle::BWACS_Never);
+    IO.enumCase(Value, "true", FormatStyle::BWACS_Always);
   }
 };