[Bug c++/70733] Wrong code with nested structs and bit field.

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70733

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
LLVM does effectively

int main() {
    b.member.member = 4;
    a = -(unsigned long)b.member.member;
    if (a != -4)
      abort();

and if you write that then GCC behavior agrees with that of LLVM.