;;;;
;;;; 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))))
+;;;; (disable (x) (setf list (remove x list))))
;;;; #+nil (enable :sb-show)
;;;; (enable :sb-after-xc-core)
;;;; #+nil (disable :sb-doc)
;; 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
;; been either made unconditional, deleted, or rewritten into
;; unrecognizability, but some remains. What remains is not maintained
;; or tested in current SBCL, but I haven't gone out of my way to
- ;; break it, either.
+ ;; break it, either.
;;
; :high-security
; :high-security-support
;; low-level thread primitives support
;;
- ;; As of SBCL 0.8, this is only supposed to work in x86 Linux, on which
- ;; system it's 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 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.
; :sb-thread
- ;; Kernel support for futexes (so-called "fast userspace mutexes") is
- ;; available in Linux 2.6 and some versions of 2.4 (Red Hat vendor
- ;; kernels, possibly other vendors too). We can take advantage of
- ;; these to do faster and probably more reliable mutex and condition
- ;; variable support. An SBCL built with this feature will fall back
- ;; to the old system if the futex() syscall is not available at
- ;; runtime
- ; :sb-futex
+ ;; 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
;; 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
+
;; 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.
;; again, if anyone's sufficiently motivated.
; :long-float
+ ;; Some platforms don't use a 32-bit off_t by default, and thus can't
+ ;; handle files larger than 2GB. This feature will control whether
+ ;; we'll try to use platform-specific compilation options to enable a
+ ;; 64-bit off_t. The intent is for this feature to be automatically
+ ;; enabled by make-config.sh on platforms where it's needed and known
+ ;; to work, you shouldn't be enabling it manually. You might however
+ ;; want to disable it, if you need to pass file descriptors to
+ ;; foreign code that uses a 32-bit off_t.
+ ; :largefile
+
;;
;; miscellaneous notes on other things which could have special significance
;; in the *FEATURES* list
;; notes on local features (which are set automatically by the
;; configuration script, and should not be set here unless you
;; really, really know what you're doing):
- ;;
+ ;;
;; machine architecture features:
;; :x86
;; any Intel 386 or better, or compatibles like the AMD K6 or K7
+ ;; :x86-64
+ ;; any x86-64 CPU running in 64-bit mode
;; :alpha
;; DEC/Compaq Alpha CPU
;; :sparc
;; :mips
;; any MIPS CPU (in little-endian mode with :little-endian -- currently
;; untested)
- ;;
+ ;;
;; (CMU CL also had a :pentium feature, which affected the definition
;; of some floating point vops. It was present but not enabled or
;; documented in the CMU CL code that SBCL is derived from, and has
;; :control-stack-grows-downward-not-upward
;; On the X86, the Lisp control stack grows downward. On the
;; other supported CPU architectures as of sbcl-0.7.1.40, the
- ;; system stack grows upward.
+ ;; system stack grows upward.
;; Note that there are other stack-related differences between the
;; X86 port and the other ports. E.g. on the X86, the Lisp control
;; stack coincides with the C stack, meaning that on the X86 there's
;; just parameterized by #!+X86, but it'd probably be better to
;; use new flags like :CONTROL-STACK-CONTAINS-C-STACK.
;;
+ ;; :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
;; :freebsd = We're intended to run under FreeBSD.
;; :openbsd = We're intended to run under OpenBSD.
;; :netbsd = We're intended to run under NetBSD.
+ ;; :darwin = We're intended to run under Darwin (including MacOS X).
;; :sunos = We're intended to run under Solaris user environment
;; with the SunOS kernel.
;; :osf1 = We're intended to run under Tru64 (aka Digital Unix
;; aka OSF/1).
- ;; (No others are supported by SBCL as of 0.7.5, but :hpux or :irix
+ ;; (No others are supported by SBCL as of 0.9.6, but :hpux or :irix
;; support could be ported from CMU CL if anyone is sufficiently
;; motivated to do so, and it'd even be possible, though harder, to
- ;; port the system to Microsoft Windows or MacOS X.)
+ ;; port the system to Microsoft Windows.)
)