[alsa-devel] alsa-lib and floating point support

[Takashi Iwai]

On Wed, 20 Sep 2017 16:45:46 +0200,
Ricard Wanderlof wrote:
> 
> 
> On Wed, 20 Sep 2017, Takashi Iwai wrote:
> 
> > > I'm trying to understand why it is critical to have hardware floating 
> > > point support in this case. The pow() function is very resource hungry, 
> > > true, but the function is only called when the plugin is loaded, and not 
> > > for instance on every sample while the stream is running, so on the whole 
> > > I would expect the impact to be minimal. Is there some other rationale 
> > > that I'm missing?
> > 
> > The softfloat option is to avoid calculation in float as much as
> > possible, i.e. alsa-lib will be built without any usage of math
> > library.
> 
> "as much as possible" sounds like the softvol case would be a reasonable 
> exception, on the other hand, if the goal is to completely avoid using the 
> softfloat library I can see the point. Is the reason to avoid dependency 
> issues, or to minimize the total resulting code size, especially on 
> systems with limited memory?

Well, actually no, because we don't link with -lm when the option is
specified, so far.  That is, the softfloat option is for controlling
whether to allow the usage of math function or not.


Takashi