"Richard Guenther" <richard.guent...@gmail.com> writes: >> That is, there are two conflicting requirements: maintaining a stable >> ABI on a single platform, and supporting a cross-platform API. I >> would argue that code which runs on a single platform and needs a >> stable ABI should avoid __attribute__ ((aligned)). That leaves us >> with the case of a cross-platform API which wants to present a stable >> ABI on each platform. (gcc's unwind code could fall into this >> category, although it's not clear to me that the alignment is actually >> exposed in a way that it matters.) Is there a way that we can handle >> that case that is better than simply documenting changes? > > I agree with you if I interpret "cross-platform" as for example > ppc vs. x86. But certainly not if it is x86_64 vs. x86_64 -mavx.
Yes, I mean x86_64 as a single platform, with or without -mavx. By cross-platform I mean code which is not interoperable. Ian
