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+---- Thread: Rule 16.5 (/showthread.php?tid=838)
Rule 16.5 - hanthen - 02-08-2011
Does this rule apply also to function pointers?
If I want to declare a function pointer which can be used for pointers to functions with different arguments, something like the following is useful:
uint8_t (* gen_u8p)();
Is this intended to be prohibited by the rule?
Re: Rule 16.5 - misra-c - 09-08-2011
No, rule 16.5 does not apply to function pointers. However, note that:
- Rule 8.1 requires a function prototype to be visible at call
- Rule 11.1 does not permit a non-prototyped function pointer to be converted to a prototyped one
Therefore, a pointer to a non-prototyped function cannot be used to call a function and cannot be converted to a pointer that could be used to call a function.
The rationale is to avoid the undefined behaviour that occurs when a function is called by means of a pointer whose type is not compatible with the called function.