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Re: Make max_align_t respect _Float128 [version 2]
On Tue, 6 Sep 2016, Florian Weimer wrote:
> So that's what ties the two things together. I still don't like what's
> implied in PR66661, that all object sizes have to be multiples of the
> fundamental alignment.
I don't think there's any such requirement in the case of flexible array
members; if you use malloc to allocate a structure with a flexible array
member, you can access as many trailing array elements as would fit within
the allocated size, whether or not that size is a multiple of either the
alignment of the structure, or the alignment of max_align_t.
> > Well, that's a conformance bug in the implementation as a whole. The
> > nonconforming modes in question are still useful and it's useful for GCC
> > to support such mallocs.
>
> PR66661 shows that GCC does not want to support such mallocs (or even glibc's
> malloc).
GCC is supposed to support all mallocs that produce results aligned to at
least MALLOC_ABI_ALIGNMENT (which may be smaller than the alignment of
max_align_t).
--
Joseph S. Myers
joseph@codesourcery.com