;;;;
;;;; Note that the recommended way to customize the features of a
;;;; local build of SBCL is not to edit this file, but instead to
-;;;; tweak customize-target-features.lisp. If you define a function
-;;;; in customize-target-features.lisp, it will be used to transform
-;;;; the target features list after it's read and before it's used.
-;;;; E.g. you can use code like this:
+;;;; tweak customize-target-features.lisp. (You must create this file
+;;;; first; it is not in the SBCL distribution, and is in fact
+;;;; explicitly excluded from the distribution in places like
+;;;; .cvsignore.) If you define a function in
+;;;; customize-target-features.lisp, it will be used to transform the
+;;;; target features list after it's read and before it's used. E.g.,
+;;;; you can use code like this:
;;;; (lambda (list)
;;;; (flet ((enable (x) (pushnew x list))
;;;; (disable (x) (setf list (remove x list))))
;; readtable configured so that the system sources can be read.
; :sb-show
- ;; Build SBCL with the old CMU CL low level debugger, "ldb". If are
- ;; aren't messing with SBCL at a very low level (e.g., trying to
- ;; diagnose GC problems, or trying to debug assembly code for a port
- ;; to a new CPU) you shouldn't need this.
- ; :sb-ldb
+ ;; Build SBCL with the old CMU CL low level debugger, "ldb". In the
+ ;; ideal world you would not need this unless you are messing with
+ ;; SBCL at a very low level (e.g., trying to diagnose GC problems, or
+ ;; trying to debug assembly code for a port to a new CPU). However,
+ ;; experience shows that sooner or later everyone lose()'s, in which
+ ;; case SB-LDB can at least provide an informative backtrace.
+ :sb-ldb
;; This isn't really a target Lisp feature at all, but controls
;; whether the build process produces an after-xc.core file. This
;; so caveat executor.
; :sb-thread
+ ;; lutex 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.
+ ;;
+ ; :sb-lutex
+
+ ;; 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-tls-segment-register-from-tls
+
;; 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
;; :stack-allocatable-closures
;; The compiler can allocate dynamic-extent closures on stack.
;;
+ ;; :alien-callbacks
+ ;; Alien callbacks have been implemented for this platform.
+ ;;
;; operating system features:
;; :linux = We're intended to run under some version of Linux.
;; :bsd = We're intended to run under some version of BSD Unix. (This