diff --git a/libcxx/include/locale b/libcxx/include/locale
--- a/libcxx/include/locale
+++ b/libcxx/include/locale
@@ -1069,7 +1069,7 @@
     int __base = 16;
     // Stage 2
     char_type __atoms[26];
-    char_type __thousands_sep = 0;
+    char_type __thousands_sep = '\x00';
     string __grouping;
     use_facet<ctype<_CharT> >(__iob.getloc()).widen(__num_get_base::__src,
                                                     __num_get_base::__src + 26, __atoms);