;; low-level thread primitives support
;;
- ;; As of SBCL 0.8, this is only supposed to work in x86 Linux with
- ;; NPTL support (usually kernel 2.6, though sme Red Hat distributions
- ;; with older kernels also have it) and is implemented using clone(2)
- ;; and the %fs segment register. Note that no consistent effort to
- ;; audit the SBCL library code for thread safety has been performed,
- ;; so caveat executor.
+ ;; 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
- ;; lutex support
+ ;; futex support
;;
;; While on linux we are able to use futexes for our locking
- ;; primitive, on other platforms we don't have this luxury. NJF's
- ;; lutexes present a locking API similar to the futex-based API that
- ;; allows for sb-thread support on x86 OS X, Solaris and
- ;; FreeBSD.
+ ;; primitive, on other platforms we don't have this luxury.
;;
- ; :sb-lutex
+ ; :sb-futex
;; On some operating systems the FS segment register (used for SBCL's
;; thread local storage) is not reliably preserved in signal
;; local storage.
; :restore-tls-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
;; 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
+
;; This affects the definition of a lot of things in bignum.lisp. It
;; doesn't seem to be documented anywhere what systems it might apply
;; to. It doesn't seem to be needed for X86 systems anyway.
;; foreign code that uses a 32-bit off_t.
; :largefile
+ ;; Enabled automatically on platforms that have VOPs to compute the
+ ;; high half of a full word-by-word multiplication. When disabled,
+ ;; SB-KERNEL:%MULTIPLY-HIGH is implemented in terms of
+ ;; SB-BIGNUM:%MULTIPLY.
+ ; :multiply-high-vops
+
+ ;; SBCL has optional support for zlib-based compressed core files. Enable
+ ;; this feature to compile it in. Obviously, doing so adds a dependency
+ ;; on zlib.
+ ; :sb-core-compression
+
;;
;; miscellaneous notes on other things which could have special significance
;; in the *FEATURES* list
;; :compare-and-swap-vops
;; The backend implements compare-and-swap VOPs.
;;
+ ;; :memory-barrier-vops
+ ;; Memory barriers (for multi-threaded synchronization) have been
+ ;; implemented for this platform.
+ ;;
;; operating system features:
;; :unix = We're intended to run under some Unix-like OS. (This is not
;; exclusive with the features which indicate which particular