Re: MPS: hash tables / obarrays

["Gerd Möllmann" <gerd.moellmann@gmail.com>]

Helmut Eller <eller.helmut@gmail.com> writes:

> On Sun, May 19 2024, Gerd Möllmann wrote:
>
>> What does it say when it fails?
>
> I think it prints a non-interned symbol.  print-gensym seems to be t.
> With exact roots:
>
> gdb --args ../src/emacs -Q --batch -l src/comp-tests.el --eval
> '(ert-run-tests-batch "comp-tests-bootstrap")'
>
> ...
>     (file=0x555555a03852 "igc.c", line=343, msg=0x555555a0387a "h->obj_type != IGC_OBJ_FWD") at igc.c:90
> #5  0x00005555559016e6 in igc_check_fwd (client=0x7fffe2e7f268) at igc.c:343
> #6  0x00005555558777a3 in XBARE_SYMBOL (a=0x2aaa8cd77588)
>     at /scratch/emacs/emacs-igc/src/lisp.h:1166
> #7  0x000055555587781b in XSYMBOL (a=0x2aaa8cd77588)
>     at /scratch/emacs/emacs-igc/src/lisp.h:1179
> #8  0x0000555555878319 in SYMBOL_INTERNED_P (sym=0x2aaa8cd77588)

> (gdb) p is_mps(0x2aaa8cd77588)
> $1 = false
> (gdb) p is_mps(0x7fffe2e7f268)
> $2 = true

I'd say a reference we didn't scan :-(.

The is_mps with a Lisp_Object doesn't work with symbols, BTW, because
the Lisp_Object doesn't contain a pointer, but an offset from lispsym.