runghc with -fobject-code and -osuf fails to find dependencies

F.hs:

module F where

import G

main = g

G.hs:

module G where

g = print ()

Running:

$ runghc --version
runghc 8.6.2
$ runghc -- -fobject-code -osuf=hs.o F
*** Exception: G.hs.o: getModificationTime:getFileStatus: does not exist (No such file or directory)
$ ls
F.hs  G.hi  G.hs  G.hs.hs.o