backwards incompatible change in 1.0.48.27)
* bug fix: occasional debugger errors in when a type-error occured in a
function with dynamic-extent &rest list.
+ * bug fix: &optional and &key supplied-p arguments in DEFSTRUCT
+ boa-construtors can be used to initialized structure slots.
changes in sbcl-1.0.49 relative to sbcl-1.0.48:
* minor incompatible change: WITH-LOCKED-HASH-TABLE no longer disables