Re: sparc64 support for Solaris

[Fred Richardson <frichard at bbn dot com>]

>> Now, do you want to help us, and submit changes to the doc that
>> document this better so that next time we can say RTFM?  ;-)

I would like to, but I'm still confused...

    Sun describes my machine (Ultra 1 Model 170) as having a 64 bit,
    v9 instruction set CPU.  It sounds like (based on the last few
    mailings on this topic) Sol2.5.x doesn't support 64 bit context
    switches.  Now, I noticed that "v9" and "sparc64" must both be
    true (you can't have one without the other).  Is this an inherent
    limitation for sparc-sol2.5, or is this a yet to be resolved
    issue for GCC's sparc support?

    Given all that, are these statements accurate?

    >> "v9" is used to specify a true 64 bit architecture.

    So an Ultra 1 Model 170 is not "true 64 bit" if it's running
    Sol2.5.x  Could it be 64 bit if it's running some other
    (newer) version of Solaris.

    >> "v8plus" is what Sun calls Solaris2 running on UltraSPARC's.

    But then what does -mcpu=ultrasparc mean?   Is there a difference
    between this and -mcpu=v8plus?

    Also, this sounds discouraging:
        sparc.h:123    /* ??? v8plus/v9/ultrasparc handling is tentative */
    I wonder if this implies that the support isn't really there yet.

I don't know the answers to these.  I also read in the Sun CC man page
that specifying "-fast" causes a set of inline math functions to be
used.  I wonder if I can use these with GCC...

            -Fred