;;;;
;;;; 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. E.g. you can use code like
-;;;; this:
+;;;; 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:
;;;; (lambda (list)
;;;; (flet ((enable (x) (pushnew x list))
;;;; (disable (x) (setf list (remove x list))))
;;;; (enable :sb-after-xc-core)
;;;; #+nil (disable :sb-doc)
;;;; list))
-;;;; That way, because customize-target-features.lisp is in
-;;;; .cvsignore, your local changes will remain local even if you use
-;;;; "cvs diff" to submit patches to SBCL.
+;;;; By thus editing a local file (one which is not in the source
+;;;; distribution, and which is in .cvsignore) your customizations
+;;;; will remain local even if you do things like "cvs update",
+;;;; will not show up if you try to submit a patch with "cvs diff",
+;;;; and might even stay out of the way if you use other non-CVS-based
+;;;; methods to upgrade the files or store your configuration.
;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
;; you are a developer.
:sb-test
- ;; :SB-PROPAGATE-FLOAT-TYPE and :SB-PROPAGATE-FUN-TYPE enable
- ;; some numeric optimizer code in the target compiler. They
- ;; correspond to the :PROPAGATE-FLOAT-TYPE and :PROPAGATE-FUN-TYPE
- ;; features in the original CMU CL code, and while documentation
- ;; existed for those, it seemed a little inconsistent. Despite the
- ;; name, :SB-PROPAGATE-FLOAT-TYPE seems to control not only
- ;; floating point optimizations, but some integer optimizations as
- ;; well.
- ;;
- ;; CROSS-FLOAT-INFINITY-KLUDGE:
- ;; * Even when these target features are enabled, the optimizations
- ;; aren't enabled in the cross-compiler, because some of them
- ;; depend on floating point infinities, which aren't in general
- ;; supported on the cross-compilation host.
- ;; * This is supported by hacking the features out of the
- ;; *SHEBANG-FEATURES* list while we're building the cross-compiler.
- ;; This is ugly and confusing and weird, but all the alternatives
- ;; that I could think of seem messy and error-prone. That doesn't
- ;; mean there's not a better way, though. Suggestions are welcome;
- ;; or if you'd like to submit patches to make this code work
- ;; without requiring floating point infinities, so that the entire
- ;; problem goes away, that might be even better! -- WHN 2001-03-22
- :sb-propagate-float-type
- :sb-propagate-fun-type
-
;; Make more debugging information available (for debugging SBCL
;; itself). If you aren't hacking or troubleshooting SBCL itself,
;; you probably don't want this set.
;; Build SBCL with the old CMU CL low level debugger, "ldb". If
;; are aren't messing with CMU CL at a very low level (e.g.
- ;; trying to diagnose GC problems) you shouldn't need this.
+ ;; 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
;; This isn't really a target Lisp feature at all, but controls
;; whether the build process produces an after-xc.core file. This
- ;; can be useful for shortening the edit/compile/debug cycle if
- ;; you're messing around with low-level internals of the system,
- ;; as in slam.sh. Otherwise you don't need it.
+ ;; can be useful for shortening the edit/compile/debug cycle when
+ ;; you modify SBCL's own source code, as in slam.sh. Otherwise
+ ;; you don't need it.
; :sb-after-xc-core
;; Enable extra debugging output in the assem.lisp assembler/scheduler
;; anyone who wants to collect such statistics in the future.
; :sb-dyncount
- ;; Peter Van Eynde's increase-bulletproofness code
+ ;; Peter Van Eynde's increase-bulletproofness code for CMU CL
;;
- ;; This is not maintained or tested in current SBCL, but I haven't
- ;; gone out of my way to remove or break it, either.
+ ;; Some of the code which was #+high-security before the fork has now
+ ;; 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.
;;
; :high-security
; :high-security-support
;; affects a lot of floating point code.
; :negative-zero-is-not-zero
- ;; It's unclear to me what this does (but it was enabled in the code
- ;; that I picked up from Peter Van Eynde, called CONSTRAIN-FLOAT-TYPE
- ;; instead of SB-CONSTRAIN-FLOAT-TYPE). -- WHN 19990224
- :sb-constrain-float-type
-
;; This is set in classic CMU CL, and presumably there it means
;; that the floating point arithmetic implementation
;; conforms to IEEE's standard. Here it definitely means that the
;; the underlying x86 hardware tries).
:ieee-floating-point
- ;; This seems to be the pre-GENCGC garbage collector for CMU CL, which was
- ;; AFAIK never supported for the X86.
- ; :gengc
-
;; CMU CL had, and we inherited, code to support 80-bit LONG-FLOAT on the x86
;; architecture. Nothing has been done to actively destroy the long float
;; support, but it hasn't been thoroughly maintained, and needs at least
projects / sbcl.git / blobdiff