my_bool is internal type, so should be SHOW_MY_BOOL

include/plugin.h

@@ -48,7 +48,7 @@ struct st_mysql_plugin _mysql_plugin_declarations_[]= {
 */
 enum enum_mysql_show_type
 {
-  SHOW_UNDEF, SHOW_BOOL, SHOW_MY_BOOL, SHOW_INT, SHOW_LONG,
+  SHOW_UNDEF, SHOW_BOOL, SHOW_INT, SHOW_LONG,
   SHOW_LONGLONG, SHOW_CHAR, SHOW_CHAR_PTR,
   SHOW_ARRAY, SHOW_FUNC
 };

sql/sql_plugin.h

@@ -23,7 +23,7 @@
 */
 #define SHOW_FUNC    SHOW_FUNC, SHOW_KEY_CACHE_LONG, SHOW_KEY_CACHE_LONGLONG, \
                      SHOW_LONG_STATUS, SHOW_DOUBLE_STATUS, SHOW_HAVE,   \
-                     SHOW_HA_ROWS, SHOW_SYS, SHOW_LONG_NOFLUSH
+                     SHOW_MY_BOOL, SHOW_HA_ROWS, SHOW_SYS, SHOW_LONG_NOFLUSH
 #include <plugin.h>
 #undef SHOW_FUNC
 typedef enum enum_mysql_show_type SHOW_TYPE;