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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


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