Hi!

On Thu, Jun 04, 2020 at 10:08:02PM +0000, Joseph Myers wrote:

quoted

The ELFv2 document specifies things like passing of quadruple precision 
floats. Indeed, VSX is needed there, but that's not a concern if you 
*don't* use quadruple precision floats.

My understanding is that the registers used for argument passing are all 
ones that exactly correspond to the Vector registers in earlier 
instruction set versions.  In other words, you could *in principle* 
produce an object, or a whole libm shared library,  [...]

And then there is the VRSAVE register, if your OS still uses that.
Let's hope not :-)

This is similar to what -mno-float128-hardware does (which actually
requires VSX hardware for the emulation library currently).


Segher