[R] Error: STRING_ELT() can only be applied to a 'character vector', not a 'builtin'

[Brahm, David]

I have a daily job that attaches hundreds of pseudo-packages containing
data as promise objects (DDP's, ref: g.data package), and plots the
results to a multi-page pdf device.  Sometimes it fails.  Under R-2.2.1
it just gave segfaults.  Under R-2.3.1 it gave this error message:

   *** caught segfault ***
  address (nil), cause 'memory not mapped'
  Traceback:
   1: load(system.file("data", paste(i, "RData", sep = "."), package =
pkg), env)
   2: g.data.load("tm.time", "hist.20051012")
   3: g.inorder(93500, tm.time, 160000)
  aborting ...
  Segmentation fault

Under R-2.4.0, it now gives this message:

  Error: STRING_ELT() can only be applied to a 'character vector', not a
'builtin'

(which appears to be generated inside main/memory.c).

I'm sorry I can't give a reproducible example, because it seems to
happen randomly, and at different points in the process.  So this is
just a shot in the dark -- does anybody recognize this behavior?  TIA.

-- David Brahm (brahm at alum.mit.edu)