src/code/defbangtype.lisp

   1 ;;;; This software is part of the SBCL system. See the README file for
   2 ;;;; more information.
   3 ;;;;
   4 ;;;; This software is derived from the CMU CL system, which was
   5 ;;;; written at Carnegie Mellon University and released into the
   6 ;;;; public domain. The software is in the public domain and is
   7 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
   8 ;;;; files for more information.
   9
  10 (in-package "SB!KERNEL")
  11 \f
  12 ;;;; the DEF!TYPE macro
  13
  14 ;;; DEF!TYPE = cold DEFTYPE, a version of DEFTYPE which at
  15 ;;; build-the-cross-compiler time defines its macro both in the
  16 ;;; cross-compilation host Lisp and in the target Lisp. Basically,
  17 ;;; DEF!TYPE does something like
  18 ;;;   (DEFTYPE SB!XC:FOO ..)
  19 ;;;   #+SB-XC-HOST (SB!XC:DEFTYPE FOO ..)
  20 ;;; except that it also automatically delays the SB!XC:DEFTYPE call,
  21 ;;; if necessary, until the cross-compiler's DEFTYPE machinery has been
  22 ;;; set up.
  23
  24 ;;; FIXME: This code was created by cut-and-paste from the
  25 ;;; corresponding code for DEF!MACRO. DEF!TYPE and DEF!MACRO are
  26 ;;; currently very parallel, and if we ever manage to rationalize the
  27 ;;; use of UNCROSS in the cross-compiler, they should become
  28 ;;; completely parallel, at which time they should be merged to
  29 ;;; eliminate the duplicate code.
  30
  31 (defmacro def!type (name &rest rest)
  32   `(progn
  33      (deftype ,name ,@rest)
  34      #+sb-xc-host
  35      ,(let ((form `(sb!xc:deftype ,(uncross name) ,@rest)))
  36         (if (boundp '*delayed-def!types*)
  37             `(push ',form *delayed-def!types*)
  38             form))))
  39
  40 ;;; machinery to implement DEF!TYPE delays
  41 #+sb-xc-host
  42 (progn
  43   (/show "binding *DELAYED-DEF!TYPES*")
  44   (defvar *delayed-def!types* nil)
  45   (/show "done binding *DELAYED-DEF!TYPES*")
  46   (defun force-delayed-def!types ()
  47     (if (boundp '*delayed-def!types*)
  48         (progn
  49           (mapc #'eval *delayed-def!types*)
  50           (makunbound '*delayed-def!types*))
  51         ;; This condition is probably harmless if it comes up when
  52         ;; interactively experimenting with the system by loading a
  53         ;; source file into it more than once. But it's worth warning
  54         ;; about it because it definitely shouldn't come up in an
  55         ;; ordinary build process.
  56         (warn "*DELAYED-DEF!TYPES* is already unbound."))))