Re: [linuxsh-dev] Re: FPU in kernel (SH-4)

[NIIBE Y. <gn...@m1...>]

Greg Banks wrote:
 >   Huh?  I seem to remember we had a problem where the gcc maintainers
 > were making this (incorrect) assumption.  So, using -m4-nofpu resulted
 > in __sh3__ being defined instead of __sh4__.  But I thought that had
 > been cleared up by now.

Yes, I had thought that, and have been using -m4-nofpu with su.  But
looking the code deeply this time, it's SH-3 actually, and __sh3__
definition seems correct.  It's quite counter-intuitive, and confusing
though.  Well, I've objdump-ed the .o produced by -m4-nofpu, and found
that the architecture is set to "SH3" not "SH4".  Ummm...

I don't know what is the actual definition of -m4-nofpu.  I belive
that it's Hitachi's request to RedHat/Cygnus, possibly for unreleased
chips (or custom chips).  I'd like to confirm Hitachi people.  What'
is that?  If there's information you could provide us, please let me
know.  Nozawa-san?

I think, it's not safe to rely on our assumption of the definition of
-m4-nofpu, as current implementation is not consistent.  It's good to
have concrete one to specify "no FPU please" option for -m4.
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