layout compatible question

[Adrian Hawryluk]

I was wondering, does this meet the criteria for "layout compatible" in
the C++ specification?

struct A {
int a[5];
};

struct B {
A b[4];
};

B obj;
int (&array)[4][5] = reinterpret_cast<int (&)[4][5]>(obj);

Regards,


Adrian
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[Victor Bazarov]

I was wondering, does this meet the criteria for "layout compatible"
in the C++ specification?

struct A {
int a[5];
};

struct B {
A b[4];
};

B obj;
int (&array)[4][5] = reinterpret_cast<int (&)[4][5]>(obj);

Regards,

I am not sure how to answer, but I am concerned that sizeof(A) is
not necessarily sizeof(int[5]), which means that sizeof(A[4]) is not
necessaruly sizeof(int[4][5]). An 'A' object can have padding added
to its 'a' member, while in an array of four arrays of five int there
will be no padding.

V