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+---- Thread: Rule 11.8: non-compatible pointees (/showthread.php?tid=1304)
Rule 11.8: non-compatible pointees - pmhill - 05-01-2017
In the following code I would like to know which of the casts are compliant for rule 11.8?
[code]
const int a[10];
int *pi;
int **ppi;
const int **cppi;
const float **cppf;
void f() {
pi = (int*) &a; /* int *
Re: Rule 11.8: non-compatible pointees - misra-c - 30-03-2017
This rule only applies to the type qualifiers of the type pointed to by the top-level pointer.
For example:
It is a violation of this rule to cast an object of type "X const *" to "Y *".
The presence/absence of type qualifiers within X or Y are covered by rule 11.3 and not by this rule.
For example:
Code:
"const int **ppci" is a "pointer to pointer to const int".
The "pointer to const int" has no type qualifiers.
"int *const *pcpi" is a "pointer to const pointer to int".
The "pointer to int" has a const type qualifier
Performing the cast "( const int**)(pcpi)" would cast away the const and violate this rule.Looking at the specific examples
Code:
pi = (int*) &a;
Casts "ptr to array of const int" to "ptr to int".
Compliant: no top-level type qualifier removed
ppi = (int**) cppi;
Casts "ptr to ptr to const int" to "ptr to ptr to int"
Compliant: no top-level type qualifier removed
ppi = (int**) cppf;
Casts "ptr to ptr to const float" to "ptr to ptr to int"
Compliant: no top-level type qualifier removed