diff --git a/include/m_ctype.h b/include/m_ctype.h
index 59ac7814aee..5fa8f28ff7a 100644
--- a/include/m_ctype.h
+++ b/include/m_ctype.h
@@ -1175,7 +1175,7 @@ extern struct charset_info_st my_charset_utf8mb3_general_nopad_ci;
 extern struct charset_info_st my_charset_utf8mb3_general_mysql500_ci;
 extern struct charset_info_st my_charset_utf8mb3_unicode_ci;
 extern struct charset_info_st my_charset_utf8mb3_unicode_nopad_ci;
-extern struct charset_info_st my_charset_utf8mb4_bin;
+extern MYSQL_PLUGIN_IMPORT struct charset_info_st my_charset_utf8mb4_bin;
 extern struct charset_info_st my_charset_utf8mb4_general_ci;
 extern struct charset_info_st my_charset_utf8mb4_nopad_bin;
 extern struct charset_info_st my_charset_utf8mb4_general_nopad_ci;
diff --git a/plugin/type_mysql_json/mysql_json.h b/plugin/type_mysql_json/mysql_json.h
index 79a784cbb6e..afbacafc9c8 100644
--- a/plugin/type_mysql_json/mysql_json.h
+++ b/plugin/type_mysql_json/mysql_json.h
@@ -41,4 +41,5 @@ enum JSONB_TYPES {
 
 bool parse_mysql_json_value(String *buffer, JSONB_TYPES type, const uchar *data,
                             size_t len, size_t depth);
+
 #endif  /* MYSQL_JSON_INCLUDED */
diff --git a/plugin/type_mysql_json/type.cc b/plugin/type_mysql_json/type.cc
index b267745a998..ec827a2182a 100644
--- a/plugin/type_mysql_json/type.cc
+++ b/plugin/type_mysql_json/type.cc
@@ -21,7 +21,7 @@
 #include <mysqld_error.h>
 #include "mysql_json.h"
 
-static const LEX_CSTRING empty_clex_str= {"", 0};
+const LEX_CSTRING empty_clex_str= {"", 0};
 
 class Type_handler_mysql_json: public Type_handler_blob
 {
diff --git a/sql/sql_type.h b/sql/sql_type.h
index 41e840d9ed7..c5d5dc7facc 100644
--- a/sql/sql_type.h
+++ b/sql/sql_type.h
@@ -3498,7 +3498,7 @@ public:
                         const Column_definition *row_start,
                         const Column_definition *row_end) const;
 };
-extern Vers_type_timestamp vers_type_timestamp;
+extern MYSQL_PLUGIN_IMPORT Vers_type_timestamp vers_type_timestamp;
 
 
 class Vers_type_trx: public Vers_type_handler