Xpressive instrument may crash due to overflow

[PhysSong]

You can reproduce the crash by playing with the preset. If you don't get crashes, try changing the numbers in the O1 tab.
crash3.xpf.zip

The positiveFraction function defined in ExprSynth.h may return a unexpected value if the input value is out of the range of int but still finite. This result in overflows when casting to int and make WaveValueFunction::operator() crash.

[gnudles]

Good point. We shall rewrite it as

inline float positiveFraction(float x)
{
	if (std::isnan(x) || std::isinf(x))
		return 0;
	float integral;
	x = modff(x, &integral);
	if (x<0)
	{
		x+=1;
	}
	return x;
}

Right?
Can you do the patch?

[PhysSong]

I think modff should be std::modf for consistency. Otherwise looks good.