[RFC, VECTOR ABI] Allow __attribute__((vector)) in GCC by default.

[Ramana Radhakrishnan]

On Wed, Oct 7, 2015 at 6:22 PM, Joseph Myers <joseph@codesourcery.com> wrote:
> On Wed, 7 Oct 2015, Jeff Law wrote:
>
>> I'm not sure why this attribute isn't documented, but clearly that should be
>> fixed.
>
> I assume the reasoning was: we document support for Cilk+ (and what's
> included in Cilk+ is externally documented).  When it becomes a generic
> GNU C attribute, that reasoning no longer applies.


I do not understand enough of this feature but since this is becoming
a GNU C attribute, what happens with functions which are marked
__attribute__((vector)) but are compiled for platforms that do not
support vector clones or have options to compile for soft float - what
is the expected behaviour for the compiler in those situations ?
Presumably the __attribute__((vector)) has no effect ? Might also be
useful to document that.

I also suppose the behaviour is dependent as usual on command line
options, target options, pragmas etc ?


regards
Ramana