[Bug target/55175] i386/sfp-exceptions.c:52:7: error: impossible constraint in 'asm'

[corsepiu at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55175

--- Comment #15 from Ralf Corsepius <corsepiu at gcc dot gnu.org> 2012-11-05 14:38:44 UTC ---
(In reply to comment #14)
> (In reply to comment #13)
> 
> > Then the problem is either in newlib or generic libgcc configury.

I meanwhile came to the latter conclusion. 

The math calls are being pulled-in by gcc's code generation from inside of
newlib's libm, but soft-fp emulation is missing in libgcc. As we have both hard
and soft-float multilib variants, I think RTEMS needs a "softfp wrapper".

> Please note that t-fdpbit is not enabled by default for x86 anymore. I don't
> know if this was intentional omission during libgcc conversion, but nobody
> missed it until today.

OK, will check.

> The second part of your patch enables TFmode soft-float, probably not needed
> for RTEMS. I think that you need either t-fdpbit or t-softfp-sfdf added to
> i[34567]86-*-rtems*)

Thanks for these hints - I am currently investigating, but ... things like
these take _a lot of time_.