changes in sbcl-1.0.56 relative to sbcl-1.0.55:

  * bug fix: fix copy-structure.  When copying from stack to heap, garbage
    could end up in the heap making GC unhappy.
    (Thanks to James Knight, lp#911027)
  * enhancements
    ** SBCL can now be built using Clang.
    ** ASDF has been updated 2.20.
  * bug fix: compiler errors when weakening hairy integer types. (lp#913232)
  * bug fix: don't complain about a too-hairy lexical environment for inlining
    when the function has never been requested for inlining.  (lp#963530)