Tag rest of my_vsnprintf users w/ ATTRIBUTE_FORMAT

This commit is the final batch of #3360’s `ATTRIBUTE_FORMAT` process,
covering various insignificant (as in, requires few-to-no
changes in addition to gaining this attribute) functions.

One of the main focus of this PR is to enable GCC `-Wformat` (by tagging
`ATTRIBUTE_FORMAT`) on ALL `my_snprintf` utilities. To be throughout,
functions that delegate to `my_vsnprintf` must also inherit this
attribute because `-Wformat` doesn’t trace argument across call stacks.

client/mysqldump.cc

@@ -628,8 +628,10 @@ static const char *load_default_groups[]=
   0 };
 static void ensure_out_dir_exists(const char *db);
 static void maybe_exit(int error);
-static void die(int error, const char* reason, ...);
-static void maybe_die(int error, const char* reason, ...);
+static void die(int error, const char* reason, ...)
+  ATTRIBUTE_FORMAT(printf, 2, 3);
+static void maybe_die(int error, const char* reason, ...)
+  ATTRIBUTE_FORMAT(printf, 2, 3);
 static void write_header(FILE *sql_file, const char *db_name);
 static void print_value(FILE *file, MYSQL_RES  *result, MYSQL_ROW row,
                         const char *prefix,const char *name,
@@ -656,7 +658,8 @@ static int dump_all_tablespaces();
 static int dump_tablespaces_for_tables(char *db, char **table_names, int tables);
 static int dump_tablespaces_for_databases(char** databases);
 static int dump_tablespaces(char* ts_where);
-static void print_comment(FILE *, my_bool, const char *, ...);
+static void print_comment(FILE *, my_bool, const char *, ...)
+  ATTRIBUTE_FORMAT(printf, 3, 4);
 
 
 static inline int cmp_database(const char *a, const char *b)

include/sql_common.h

@@ -109,7 +109,8 @@ void set_stmt_error(MYSQL_STMT *stmt, int errcode, const char *sqlstate,
                     const char *err);
 void set_mysql_error(MYSQL *mysql, int errcode, const char *sqlstate);
 void set_mysql_extended_error(MYSQL *mysql, int errcode, const char *sqlstate,
-                              const char *format, ...);
+                              const char *format, ...)
+                              ATTRIBUTE_FORMAT(printf, 4, 5);
 
 /* client side of the pluggable authentication */
 struct st_vio;

plugin/query_response_time/query_response_time.cc

@@ -136,7 +136,7 @@ private:
   ulonglong m_bound[OVERALL_POWER_COUNT];
 };
 
-static
+ATTRIBUTE_FORMAT(printf, 3, 0) static
 size_t print_time(char* buffer, std::size_t buffer_size, const char* format,
                   uint64 value)
 {

sql/sp.cc

@@ -431,6 +431,7 @@ public:
   Proc_table_intact() : m_print_once(TRUE) { has_keys= TRUE; }
 
 protected:
+  ATTRIBUTE_FORMAT(printf, 3, 4)
   void report_error(uint code, const char *fmt, ...) override;
 };
 

storage/federatedx/federatedx_io_mysql.cc

@@ -70,7 +70,8 @@ public:
   federatedx_io_mysql(FEDERATEDX_SERVER *);
   ~federatedx_io_mysql() override;
 
-  int simple_query(const char *fmt, ...);
+  // 1st arg is the implicit `this`
+  int simple_query(const char *fmt, ...) ATTRIBUTE_FORMAT(printf, 2, 3);
   int query(const char *buffer, size_t length) override;
   FEDERATEDX_IO_RESULT *store_result() override;
 

storage/maria/ha_maria.cc

@@ -401,7 +401,7 @@ static void _ma_check_print(HA_CHECK *param, const LEX_CSTRING *msg_type,
 
 
 // collect errors printed by maria_check routines
-
+ATTRIBUTE_FORMAT(printf, 3, 0)
 static void _ma_check_print_msg(HA_CHECK *param, const LEX_CSTRING *msg_type,
                                 const char *fmt, va_list args)
 {