Re: import-lisp-macro

[Keisuke Nishida <kxn30 at po dot cwru dot edu>]

Kalle Olavi Niemitalo <tosi@ees2.oulu.fi> writes:

> > It seems this version has some GC-related bugs
> 
> Is there a way to fix them?

I think so, but I have not investigated it yet.

bash$ gdb emacs core
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This GDB was configured as "i386-redhat-linux"...

warning: exec file is newer than core file.
Core was generated by `emacs'.
Program terminated with signal 11, Segmentation fault.
Reading symbols from /usr/X11R6/lib/libXaw.so.6...done.
Reading symbols from /usr/X11R6/lib/libXmu.so.6...done.
Reading symbols from /usr/X11R6/lib/libXt.so.6...done.
Reading symbols from /usr/X11R6/lib/libSM.so.6...done.
Reading symbols from /usr/X11R6/lib/libICE.so.6...done.
Reading symbols from /usr/X11R6/lib/libXext.so.6...done.
Reading symbols from /usr/X11R6/lib/libX11.so.6...done.
Reading symbols from /usr/lib/libncurses.so.4...done.
Reading symbols from /lib/libm.so.6...done.
Reading symbols from /lib/libc.so.6...done.
Reading symbols from /usr/local/lib/libguile.so.7...done.
Reading symbols from /lib/ld-linux.so.2...done.
Reading symbols from /lib/libdl.so.2...done.
Reading symbols from /lib/libnss_files.so.2...done.
#0  0x401fb4e1 in __kill () from /lib/libc.so.6
DISPLAY = :0
TERM = dumb
Breakpoint 1 at 0x8093dc7: file emacs.c, line 277.
Breakpoint 2 at 0x8085f6e: file xterm.c, line 5335.
(gdb) bt
#0  0x401fb4e1 in __kill () from /lib/libc.so.6
#1  0x8093db6 in fatal_error_signal (sig=11) at emacs.c:249
#2  0x401fb408 in __restore ()
    at ../sysdeps/unix/sysv/linux/i386/sigaction.c:127
#3  0x40319067 in scm_make_stack (args=10612) at stacks.c:467
#4  0x403206a9 in ss_handler (data=0x0, tag=1077217144, throw_args=1077803392)
    at throw.c:315
#5  0x40320d19 in scm_ithrow (key=1077217144, args=1077803392, noreturn=1)
    at throw.c:683
#6  0x402eb036 in scm_error (key=1077217144, subr=0x0, 
    message=0x403388a0 "Unbound variable: ~S", args=1077803408, rest=8564)
    at error.c:82
#7  0x402ec17e in scm_lookupcar (vloc=1077808224, genv=1077814064, check=1)
    at eval.c:349
#8  0x402ec288 in scm_eval_car (pair=1077808224, env=1077814064) at eval.c:434
#9  0x402ecce4 in iqq (form=1077808232, env=1077814064, depth=1) at eval.c:847

Well, this might not be a GC bug...

> > An important change has been made.  All imported lisp functions now
> > returns a kind of pointer to a lisp value.
> 
> I think this is bad.  A function like buffer-substring should
> return a Scheme string directly, because that's what it will do
> in a Guile-based Emacs.  There could be a separate function
> buffer-substring-lispref for cases where the Lisp reference is
> needed.

Yes, we can do that by defining this:

  (import-lisp-function buffer-substring buffer-substring-lispref)

  (define (buffer-substring . args)
    ((apply buffer-substring-lispref args)))

My point is lisp-eval should have this change for completeness.
And that's why I think we need to develop a new set of functions
for Scheme programs.

-- Kei