* bug fix: COMPILE-FILE did not warn about undefined variable
references at toplevel, and LOAD of the resulting fasl did
not signal an error.
+ * bug fix: functions with non-required arguments used to end up with
+ (SB-C::&OPTIONAL-DISPATCH ...) as their name.
+ * bug fix: redefining a function with non-required arguments didn't
+ update the system's knowledge about its call signature properly.
changes in sbcl-1.0.21 relative to 1.0.20:
* new feature: the compiler is able to track the effective type of a