isnan() and family seems to have stopped working in my code. The only thing I can remember is updating from 1.36 to 1.37. Any idea why the following wouldn't work?

float nan = FP_NAN;
int ret = 0xdeadbeef;
ret = (boost::math::isnan)(nan);

isnan never returns anything. The value of ret is still 0xdeadbeef after invoking isnan()

I'm on OSX10.5.6 using XCode 3 if that helps.

Thijs