math.pow fails at compile-time; is this a bug?

[Caligo]

template T(){
  enum a = pow(3.0, 2);
  enum b = pow(3, 2.0);
}

unittest
{
  alias T!() t;
}

compiling that I get:

/home/b/phobos/std/math.d(2369): Error: Cannot convert &real to ushort* at
compile time
/home/b/phobos/std/math.d(3292):        called from here: isNaN(y)
/home/b/phobos/std/math.d(3403):        called from here:
impl(x,cast(real)y)
/home/b/phobos/std/math.d(3239):        called from here: pow(cast(real)x,y)
t.d(478):        called from here: pow(3,2)
t.d(485): Error: template instance units.T!() error instantiating

I guess this a bug?  any workarounds?