https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84516
--- Comment #2 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- See also bug 70733, another bug with these types being user-exposed for bit-fields for C++. For C++ (unlike C), the existence of these types internally in the compiler should never be user-visible, because bit-field width is explicitly not part of the type for C++.