https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89624
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- No, it's just a different, but still conforming, interpretation of the standard. > For an enumeration whose underlying type is not fixed, the underlying type > is an integral type that can represent all the enumerator values defined > in the enumeration. If no integral type can represent all the enumerator > values, the enumeration is ill-formed. It is implementation-defined which > integral type is used as the underlying type except that the underlying > type shall not be larger than int unless the value of an enumerator > cannot fit in an int or unsigned int. By default GCC uses int or unsigned int, even if a smaller type would suffice. I think that is required by the psABI. The -fshort-enums switch says to ignore the platform ABI and make the type as small as possible, i.e. use a different implementation-defined integral type. The HLE bits are outside the standard though, so if we were to stop caring about things outside the standard, we could just remove the constants for the HLE bits, instead of trying to make them work with -fshort-enums :-)
