errors during GC

[Marius Vollmer]

Hi,

is it actually safe to call scm_misc_error, say, from scm_gc_mark?
Right now, we have this code in scm_gc_mark

      if (!(i < scm_numptob))
        SCM_MISC_ERROR ("undefined port type", SCM_EOL);

which looks helpful, but can we break out of the scm_gc_mark without
doing the sweep?  It might be possible because of the GC cards
(i.e. the mark bits are no longer in the cells themselves (what does
this gain us, btw?)), but if this actually by design, we should put a
comment somewhere that explicitly states that we can safely break out
of the middle of the mark phase.

Also, the tags docs in tags.h should be updated for the card scheme.