+ * enhancement: dynamic-extent for &rest lists stack allocate only their
+ spines, not their argumets. While portable code should not rely on this,
+ particularly in combination with inlining, it should make dynamic-extent
+ easier to use safely.
+ * enhancement: SB-POSIX improvements:
+ ** WNOHANG and WUNTRACED are exported.
+ ** SYSCALL-ERROR now also provides the name of the failing system call.
+ * enhancement: --script improvements:
+ ** errors on standard input, output, and error streams are handled and
+ cause scripts to exit silently, making them easier to use in shell
+ pipelines.
+ ** backtraces from scripts now go to standard error instead of the
+ terminal even if one is available.
+ ** --script can be an argument, causing the script to be loaded from
+ standard input.
+ * enhancement: MAKE-ALIEN-STRING provides an easy way to transport lisp
+ strings to foreign memory.
+ * enhancement: (SETF GC-LOGFILE) allows logging garbage collections to
+ a file, making it easier to understand heap dynamics.
+ * optimization: using a &REST argument only in APPLY or VALUES-LIST calls
+ allows the compiler to automatically elide rest-list allocation so long as
+ the call sites are in functions that the compiler knows cannot escape.
+ (lp#504575)
+ * optimization: CALL-NEXT-METHOD using explicit arguments is faster,
+ especially in safe code when none of the required arguments have changed
+ their identities.