- ;; multiprocessing support
- ;;
- ;; This is not maintained or tested in current SBCL. I haven't gone out
- ;; of my way to break it, but since it's derived from an old version of
- ;; CMU CL where multiprocessing was pretty shaky, it's likely to be very
- ;; flaky now.
- ;; :MP enables multiprocessing
- ;; :MP-I486 is used, only within the multiprocessing code, to control
- ;; what seems to control processor-version-specific code. It's
- ;; probably for 486 or later, i.e. could be set as long as
- ;; you know you're not running on a 386, but it doesn't seem
- ;; to be documented anywhere, so that's just a guess.
- ; :mp
- ; :mp-i486
+ ;; low-level thread primitives support
+ ;;
+ ;; As of SBCL 1.0.33.26, threads are part of the default build on
+ ;; x86oid Linux. Other platforms that support them include
+ ;; x86oid Darwin, FreeBSD, and Solaris.
+ ; :sb-thread
+
+ ;; futex support
+ ;;
+ ;; While on linux we are able to use futexes for our locking
+ ;; primitive, on other platforms we don't have this luxury.
+ ;;
+ ; :sb-futex
+
+ ;; On some operating systems the FS segment register (used for SBCL's
+ ;; thread local storage) is not reliably preserved in signal
+ ;; handlers, so we need to restore its value from the pthread thread
+ ;; local storage.
+ ; :restore-fs-segment-register-from-tls
+
+ ;; On some x86oid operating systems (darwin) SIGTRAP is not reliably
+ ;; delivered for the INT3 instruction, so we use the UD2 instruction
+ ;; which generates SIGILL instead.
+ ; :ud2-breakpoints
+
+ ;; Support for detection of unportable code (when applied to the
+ ;; COMMON-LISP package, or SBCL-internal pacakges) or bad-neighbourly
+ ;; code (when applied to user-level packages), relating to material
+ ;; alteration to packages or to bindings in symbols in packages.
+ :sb-package-locks
+
+ ;; Support for the entirety of the 21-bit character space defined by
+ ;; the Unicode consortium, rather than the classical 8-bit ISO-8859-1
+ ;; character set.
+ :sb-unicode
+
+ ;; Support for a full evaluator that can execute all the CL special
+ ;; forms, as opposed to the traditional SBCL evaluator which called
+ ;; COMPILE for everything complicated.
+ :sb-eval
+
+ ;; Record source location information for variables, classes, conditions,
+ ;; packages, etc. Gives much better information on M-. in Slime, but
+ ;; increases core size by about 100kB.
+ :sb-source-locations
+
+ ;; Record xref data for SBCL internals. This can be rather useful for
+ ;; people who want to develop on SBCL itself because it'll make M-?
+ ;; (slime-edit-uses) work which lists call/expansion/etc. sites.
+ ;; It'll increase the core size by major 5-6mB, though.
+ ; :sb-xref-for-internals
+
+ ;; We support package local nicknames. No :sb-prefix here as we vainly
+ ;; believe our API is worth copying to other implementations as well.
+ ;; This doesn't affect the build at all, merely declares how things are.
+ :package-local-nicknames