Compiler warning

Hi

I see the following behavior

LAZY 27 > (defun bar (x) (let ((f 'gnao)) (if x 42 (funcall f 40 2))))
BAR

LAZY 28 > (compile 'bar)

The following function is undefined:
GNAO which is referenced by BAR
BAR
NIL
NIL



This is a summary case.  What I really have is a more complex macro  
that expands in somethin like that.

So, it looks like the compiler is constant folding the reference to F  
and then issuing the warning.
Is that the case?  Any suggestion about how to avoid it?

Thanks

--
Marco Antoniotti