diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index c270c62e213..ad960336e8d 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -86,6 +86,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc_hooks.h"
 #include "utils/memutils.h"
+#include "utils/pg_locale.h"
 #include "utils/ps_status.h"
 #include "utils/varlena.h"