1 files changed, 1 insertions, 0 deletions
diff --git a/sql/sql_sort.h b/sql/sql_sort.h
index 88f719b3593..2b2c08b59cd 100644
--- a/sql/sql_sort.h
+++ b/sql/sql_sort.h
@@ -20,6 +20,7 @@
 #include "my_base.h"                            /* ha_rows */
 #include <my_sys.h>                             /* qsort2_cmp */
 #include "queues.h"
+#include "sql_string.h"
 #include "sql_class.h"
 
 class Field;