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Subject: Re: Mixing hard and soft floating point?
From: Peter Bergner <bergner@vnet.ibm.com>
To: Wolfgang Denk <wd@denx.de>
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Date: Sun, 18 Oct 2009 19:57:24 -0500
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On Sat, 2009-10-17 at 21:34 +0200, Wolfgang Denk wrote:
> Dear Joakim Tjernlund,
> > OK, but then you don't mix some libs/apps with soft and other
> > apps/libs with hard FP?
> 
> No, we never tried that. Sounds scary to me.

And dangerous.  Hard-float and soft-float are ABI incompatible, so you
cannot mix and match obj files and libs compiled with those two options.
They all have to be hard-float or they all have to be soft-float.
Think about a function compiled with hard-float calling a soft-float
libm routine.  The hard-float routine will pass its args in via FP
regs and the soft-float lib routine will be looking for them in the
integer registers.

Peter