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Re: A problem with aligment attribute

H. J. Lu wrote: 
void
foo (int i, float128_type x)
{
...
  if (((long) (&x.word0) & 15) != 0)
    abort ();

You are asking for a function argument to have 16-byte alignment, but the ABI does not support that. PARM_BOUNDARY is 32, so an argument can have at most 4 byte alignment.

Try passing in a pointer, or using a global or local instead of an argument.

We could perhaps emit a warning if someone tries to use an aligned type in an argument list, and the aligned type requires greater alignment than the ABI will give. I don't think we should be changing ABIs to make this work.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com

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