Creating imaginary inf/nan in GCC

[Kaveh R. Ghazi]

From: "Joseph S. Myers" <joseph@codesourcery.com>

> On Thu, 29 Jan 2009, Kaveh R. GHAZI wrote:
>
>> I don't think these results are a bug, rather it's just an artifact of 
>> the
>> way complex multiplcation is done and having these special values in
>
> See bug 24581.  Some aspects are a bug (GCC doesn't handle mixed
> real/complex arithmetic the way it should), some are the lack of imaginary
> types (though the only use of imaginary types I know of is this one for
> building up constants, and no-one on the Power ABI working group could
> find any implementation for Power Architecture that actually supports
> imaginary types).

Thanks for the PR pointer.  I'm going to ask the obvious question, if 
there's an obvious answer please excuse me.  :-)

Would it be sufficient and correct to treat (0.0 + I) * y as a special case 
for MULT_EXPR and just swap the real and imaginary parts of "y" in the 
result?

        --Kaveh