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Re: [TESTCASE] Minimized testcase for AltiVec segfault


>>> Why can't varargs and vector arguments be supported under the SVR4
>>> ABI?
>>
>> because things won't be aligned properly.  and if they were,
>> we'd no longer be SVR4 abi compliant.
>
> Can you explain what doesn't get aligned?  SVR4 always had 16-byte
> stack alignment (unlike some other ppc ABIs).

maybe i'm confusing myself here... how about the other ppc abis?
i didn't mean to single svr4 out.

>>> Isn't altivec still useful even if you can't pass vectors as
>>> arguments?
>>
>> sure, but we don't need a flag to do that.
>
> But we do!  We need a flag to tell the compiler _not_ to use altivec
> instructions for block copies, for example, on non-altivec chips.

but that's only dependant on -maltivec, not on abi. right?

--
Aldy Hernandez                                E-mail: aldyh@redhat.com
Professional Gypsy Lost in Australia
Red Hat, Inc.


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