diff --git a/src/include/utils/pg_locale.h b/src/include/utils/pg_locale.h
index 2e6dba1..2d2146c 100644
--- a/src/include/utils/pg_locale.h
+++ b/src/include/utils/pg_locale.h
@@ -15,7 +15,15 @@
 #include <locale.h>
 #ifdef LOCALE_T_IN_XLOCALE
 #include <xlocale.h>
-#endif
+#else							/* LOCALE_T_IN_XLOCALE */
+#ifdef HAVE_MBSTOWCS_L
+#include <xlocale.h>
+#else
+#ifdef HAVE_WCSTOMBS_L
+#include <xlocale.h>
+#endif   /* HAVE_WCSTOMBS_L */
+#endif   /* HAVE_MBSTOWCS_L */
+#endif   /* LOCALE_T_IN_XLOCALE */
 
 #include "utils/guc.h"