https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101832
--- Comment #8 from qinzhao at gcc dot gnu.org --- (In reply to Jakub Jelinek from comment #3) > This is intentional, if you embed an aggregate with flex array into another > struct and ask not to cross the field boundaries (i.e. bos1), then the size > of that field is exactly what is the maximum size. As we discussed in PR 107952 (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107952): GCC extension accepts the following two cases: **Case 1: struct A { char data[1]; }; struct B { int n; struct A a; }; as if the a.data[] array is a flex-array. **Case 2: struct C { int n; struct A a; int x; }; as if a.data[] can be up to 4 elements. So, what's you mean by "not to cross the field boundaries" is for the above Case 2? For Case 1, we should treat A.data as flexible array, and then B.A as a structure that has flexible array, therefore B.A's size is flexible too. Is my understanding correct?
