;; original CMU CL code.)
; :sb-show-assem
+ ;; Compile the C runtime with support for low-level debugging output
+ ;; through FSHOW and FSHOW_SIGNAL. If enabled, this feature allows
+ ;; users to turn on such debugging output using environment variables at
+ ;; run-time.
+ ; :sb-qshow
+
;; Setting this makes SBCL more "fluid", i.e. more amenable to
;; modification at runtime, by suppressing various INLINE declarations,
;; compiler macro definitions, FREEZE-TYPE declarations; and by
;; 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
;; handlers, so we need to restore its value from the pthread thread
;; local storage.
- ; :restore-tls-segment-register-from-tls
+ ; :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
;; 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
+
;; 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.
;; 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
+
+ ;; On certain thread-enabled platforms, synchronization between threads
+ ;; for the purpose of stopping and starting the world around GC can be
+ ;; performed using safepoints instead of signals. Enable this feature
+ ;; to compile with safepoints and to use them for GC.
+ ;; (Replaces use of SIG_STOP_FOR_GC.)
+ ; :sb-safepoint
+
+ ;; When compiling with safepoints, the INTERRUPT-THREAD mechanism can
+ ;; also use safepoints to roll the target thread to a point at which it
+ ;; can be interrupted safely, instead of using a signal for this
+ ;; purpose. Enable this feature in addition to :SB-SAFEPOINT to enable
+ ;; such behaviour.
+ ;; (Replaces use of SIGPIPE, except to wake up syscalls.)
+ ; :sb-thruption
+
+ ;; When compiling with safepoints and thruptions, the TIMER facility
+ ;; can replace its use of setitimer with a background thread.
+ ;; (Replaces use of SIGALRM.)
+ ; :sb-wtimer
+
;;
;; miscellaneous notes on other things which could have special significance
;; in the *FEATURES* list