Thank you (and others) for your answers. Now I'm just as smart as before, however.
Is it a supported, documented, 'long term' feature we can rely on or not? If yes, I would expect it to be properly documented. If not, never mind. > Gesendet: Montag, 19. August 2019 um 16:08 Uhr > Von: "Alexander Monakov" <amona...@ispras.ru> > An: "Richard Earnshaw (lists)" <richard.earns...@arm.com> > Cc: "Paul Koning" <paulkon...@comcast.net>, "Markus Fröschle" > <mar...@mubf.de>, gcc@gcc.gnu.org > Betreff: Re: asking for __attribute__((aligned()) clarification > > On Mon, 19 Aug 2019, Richard Earnshaw (lists) wrote: > > > Correct, but note that you can only pack structs and unions, not basic > > types. > > there is no way of under-aligning a basic type except by wrapping it in a > > struct. > > I don't think that's true. In GCC-9 the doc for 'aligned' attribute has been > significantly revised, and now ends with > > When used as part of a typedef, the aligned attribute can both increase and > decrease alignment, and specifying the packed attribute generates a > warning. > > (but I'm sure defacto behavior of accepting and honoring reduced alignment on > a typedef'ed scalar type goes way earlier than gcc-9) > > Alexander >
