[Rd] splinefun bug (PR#7290)

[kjetil at acelerate.com]

The following reliably bombs R, or at least rw2000 (windows XP):

test <- splinefun(vector(length=0), vector(length=0))
test(1)

-- 

Kjetil Halvorsen.

Peace is the most effective weapon of mass construction.
               --  Mahdi Elmandjra