https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98317
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I'm not convinced it is a bug. Because vector_size by definition increases the
alignment, say if you have vector_size on int, the vector type doesn't have
alignof(int) alignment, but alignment of the vector type.
Similarly, if one uses
typedef int T __attribute__((aligned (1)));
typedef T V __attribute__((vector_size (16)));
I'd argue that V should have still 16-byte alignment.
Having the attributes on the same typedef or on the same type is a grey area,
but what we do currently matches what is done with the separate typedefs.
I'd strongly suggest to use separate typedefs, i.e. one that makes a vector
type
typedef float V __attribute__((vector_size (16)));
and then another one that makes it unaligned:
typedef V U __attribute__((aligned (1)));
