On Fri, 3 Jan 2014, Marek Polacek wrote: > As Paul Eggert says in the PR, we shouldn't warn for enum bit-fields > in C99/C11 mode. C11 6.7.2.1 (5) says "A bit-field shall have a type > that is a qualified or unqualified version of _Bool, signed int, > unsigned int, or some other implementation-defined type.", so ISTM > that enum bit-fields should be fine. OTOH, I would warn in ISO C > mode. It's true that no constraint is violated, but in C89 in 3.5.2.1 > Semantics there's: "A bit-field may have type int, unsigned int, or > signed int." so it seems desirable to warn in this case. > > Regtested/bootstrapped on x86_64-linux, ok for trunk?
Implementation-defined behavior is documented in implement-c.texi, so this patch is incomplete as it doesn't update that file where it says: No other types are permitted in strictly conforming mode. @c Would it be better to restrict the pedwarn for other types to C90 @c mode and document the other types for C99/C11 mode? (And this isn't just about enums, but other integer types as well, so the test should cover those.) -- Joseph S. Myers jos...@codesourcery.com