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+---- Thread: Dir 4.8 2 struct pointers in a Translation unit (/showthread.php?tid=1145)
Dir 4.8 2 struct pointers in a Translation unit - misra-c - 13-02-2015
What happens if there are 2 pointers to a struct/union in a translation unit. One which accesses the details of the struct/union and the other does not. For Example:
File1.h
Code:
struct X { int32_t i1 };
typedef struct X * ptrX;
extern void use_ptrX ( ptrX p );File1.c
Code:
void fn ( ptrX a, ptrX b )
{ /* no reference to a->i1 in translation unit - does the type of "a" need to be opaque? */
use_ptrX ( a );
use_int32 ( b -> i1 ) ;
}Re: Dir 4.8 2 struct pointers in a Translation unit - misra-c - 13-02-2015
The implementation of an object need only be hidden if all pointers to that type in a translation unit are never dereferenced and there are no other reasons for the internal details of the structure/union to be known.
In the above example "ptrX a" is complaint, because member “i1†from “struct X†is accessed elsewhere in the translation unit.