merge from stable, revs:

  1.41.4.1  +4 -1      fptools/ghc/compiler/nativeGen/AbsCStixGen.lhs
  1.61.4.3  +10 -0     fptools/ghc/driver/mangler/ghc-asm.lprl

  Place a zero word after each reversed vector table, so that the vtbl
  label is really in the section we would like to claim it is in.  This
  is needed for the GC to work correctly.  Fixes a GHCi segfault
  reported by Ryszard Kubiak.

  1.41.4.2  +7 -0      fptools/ghc/compiler/nativeGen/AbsCStixGen.lhs
  1.61.4.4  +18 -0     fptools/ghc/driver/mangler/ghc-asm.lprl

  Add comments, much longer than the fix itself, giving explaination
  for yesterday's dummy-word-after-vtbl fix.