marking code, and make marker routines only responsible for
turning up outgoing pointers.
* gc.c (scm_gc_mark): Set the mark bit on ports and smobs here,
before calling the marking function. Don't call the marking
function if it's zero.
* markers.c (scm_mark0): Just return #f. This function isn't
necessary at all now, but it's harmless to call it. We'll leave
it in so other folks' code doesn't croak at link time.
(scm_markcdr): Don't call SCM_SETGC8MARK.
* async.c (mark_async): Don't call SCM_SETGC8MARK.
* dynl.c (mark_dynl_obj): Same.
* root.c (mark_root): Same.
* srcprop.c (marksrcprops): Same.
* unif.c (markra): Same.
* variable.c (scm_markvar): Same.
* ports.c (scm_markstream): Same.
(void_port_ptob): Specify zero for our marking function.
* debug.c (debugobjsmob): Same.
* dynwind.c (guardsmob): Same.
* filesys.c (dir_smob): Same.
* fluids.c (fluid_smob): Same.
* fports.c (scm_fptob, scm_pipob): Same.
* mallocs.c (mallocsmob): Same.
* regex-posix.c (regex_t_smob): Same.
* smob.c (freecell, flob, bigob): Same.
* threads.c (thread_smob, mutex_smob, condvar_smob): Same.
* throw.c (jbsmob, lazy_catch_funs): Same.
eval.h, feature.c, filesys.c, fports.c, gc.c, gsubr.c, init.c,
ioext.c, kw.c, list.c, load.c, mallocs.c, numbers.c, numbers.h,
pairs.c, pairs.h, ports.c, ports.h, posix.c, procprop.c, procs.c,
procs.h, ramap.c, read.c, root.c, srcprop.c, srcprop.h,
strports.c, symbols.c, tags.h, throw.c, unif.c, variable.c,
vports.c: Cleaned up use of pairs: Don't make any special
assumptions about the internal structure of selectors and
mutators: SCM_CXR (<e1>) = <e2> --> SCM_SETCXR (<e1>, <e2>),
SCM_CXR (<e1>) &= <e2> --> SCM_SETAND_CXR (<e1>, <e2>) etc.
(Among other things, this change makes it easier to build Guile
with certain compilers which have problems with casted lvalues.)
