Float division by zero is not constant-folded

If I do

module Lib where

f :: Float
f = 0.0/0.0

Then I see in the resulting Core:

f = case GHC.Prim.divideFloat# 0.0# 0.0# of wild2_aCm
    { __DEFAULT ->
    GHC.Types.F# wild2_aCm
    }

Rather than a literal for NaN (do we have those?). Division by other constants seems to work.