0641			[C] '%s' in 'struct' or 'union' type may not have function type.
	Constraint violations				REFERENCE - ISO:C90-6.5.2.1 Structure and Union Specifiers - Constraints

/*PRQA S 553,2213,2216 ++*/

struct ST1 { int mode; int f(void);};        /* Message 0641 - f has function type */

struct ST2 { int mode; int (*f)(void);};     /* OK           - f has type pointer to function */

See also:

• 0640 [C] '%s' in 'struct' or 'union' type may not have 'void' type.
• 0642 [C] '%s' in 'struct' or 'union' type may not be an array of unknown size.
• 0643 [C] '%s' in 'struct' or 'union' type may not be a 'struct' or 'union' with unknown content.