Re: disabling libm

[Joel Sherrill <joel dot sherrill at OARcorp dot com>]

"J. Johnston" wrote:
> 
> Joel Sherrill wrote:
> > Hi,
> >
> > I am trying to update my tic4x toolset.  The tic4x does not
> > use IEEE FP.  The last time I looked into this, the newlib libm
> > was very IEEE FP format dependent.  It would be easier to not
> > have newlib's libm for now.  Is it possible to completely disable
> > it for a target?
> >
> 
> It is definitely "possible" via configuration; the question is whether
> it is warranted.  Does the build fail or do any of the libm files
> placed in libc cause problems?  I assume you are already just linking
> in your own libm stuff anyway.

I have managed to get a build to complete at this point with libm.
Speaking without doing an up to date analysis, this libm is heavily 
dependent on IEEE floating point format.  The tic4x target is not
IEEE so very little if anything works even if it compiles.  

I have a hacked together libm substitute that is far from optimal
but tries to be portable.  But really I would like to see newlib
work better with non-IEEE FPUs.  Any ideas?

On a similar tangent, I am slowly updating Ran Cabell's patches to 
newlib 1.8.2 for newlib 1.11.0.  They included a setjmp and some
patches to the string code to account for the c4x not being byte 
addressable.  Mostly very minor stuff scattered out which I will
try to carve into manageable pieces to submit and discuss.  

And (so far) I haven't confirmed a current email address for Ran.
Is he still around?  Ran.. are you out there?

> -- Jeff J.

-- 
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