[Sbcl-devel] Re: Cold building PCL

[Gerd M. <ger...@t-...>]

Christophe Rhodes <cs...@ca...> writes:

> What it does: in essence, it brings pcl/defclass and pcl/defs into the
> build.  But the way I've done it is perhaps along the path of least
> resistance, and I want to see if people think that there's a chance of
> getting to where we want to be by going down this route.

I don't know if it is relevant for SBCL, or even if even everything
works as it should, but anyway, maybe it's food for thought...

I got an idea today that allowed me to create a kitchen-sink CMUCL
kernel.core (the core created by cold-loading fasl files).  The core
contains everything, but most notably it contains the compiler and
PCL, and it seems to get at least some things right:

  gerd@gerd:~/cmucl% fasl/lisp/lisp -core fasl/lisp/kernel-with-compiler-and-pcl.core
  In initial-function, and running.
  GLOBALDB-INIT
  FDEFN-INIT
  TYPEDEF-INIT
  CLASS-INIT
  TYPE-INIT
  Calling top-level forms.
  Basic initializations done.
  OS-INIT
  FILESYS-INIT
  READER-INIT
  STREAM-INIT
  LOADER-INIT
  PACKAGE-INIT
  SIGNAL-INIT
  PROCLAIM-INIT
  CLASS-FINALIZE
  PCL init...
  PCL init done.
  Extended initializations...
  Done initializing.

  CMU Common Lisp kernel core image 4.0(?).
  [You are in the LISP package.]
  * (fboundp 'pcl::generic-function-p)

  T
  * (pcl::find-class t)

  #<Built-In-Class T {4A7962ED}>
  * (defclass foo () ())

  #<Standard-Class FOO {50B0CE1D}>
  * (make-instance 'foo)

  #<FOO {50B0F51D}>

PCL is built as usually in CMUCL, with only a small change in defsys
that prevents byte-compilation.  All the PCL init phase above
currently does is:

  (defun pcl-init ()
    (setq *the-pcl-package* (find-package "PCL"))
    (setq *boot-state* nil))

The idea behind this was that executing the various PCL stuff in
*LISP-INITIALIZATION-FUNCTIONS* in %INITIAL-FUNCTION in sequence
should correspond roughly to what happens when PCL is bootstrapped in
a normal build, where one file after the other is compiled and
immediately afterwards loaded.

So, PCL effectively bootstraps in the cold core.  Or so it seems; I'm
not sure if I'm not overlooking something crucial.  All input welcome.

Also not clear to me is how to proceed from here.  Hm...