On 04/05/17 18:08, Jakub Jelinek wrote: > On Wed, Apr 05, 2017 at 05:03:33PM +0100, Jonathan Wakely wrote: >>> I wanted to say it behaves mostly like __attribute__((may_alias)) >>> except that may_alias only has an effect on pointers and references >>> but not when accessing an object directly, (I hope you know what >>> I mean). >> >> And may_alias is not a very helpful name either. >> >> I much prefer Richi's suggestion of typeless_storage. >> >> But I'm not convinced we need the attribute at all. If a struct >> containing an array of std::byte or unsigned char has the property >> already then that's good. I don't think we need a non-portable way to >> make other types behave the same. If you can change the code to use a >> new GCC attribute then you can change the code to use an array of >> unsigned char, and be portable. > > It will only work that way in C++ though, so if you want to achieve > the same in C, which doesn't have any special case for unsigned char > arrays nor std::byte, you need an attribute. >
Yes, exactly. I really want to reach the deadline for gcc-7. Fixing the name is certainly the most important first step, and if everybody agrees on "typeless_storage", for the name I can start with adjusting the name, and look into how to use a spare type-flag that should be a mechanical change. Bernd.
