prototypes.
* eval.c: Make scm_m_mody's 3rd argument be a const char *, not a
char *. ANSI prototypes caught this.
* strorder.c: Use GUILE_PROC1 for the couple SCM_PROC1 expansions
that I missed.
* scm_validate.h: Use SCM_BOOLP for validating bools. Do not
expand macros if SCM_DOCSTRING_SNARF.
function headers and argument checking. Switched SCM_PROC,
SCM_PROC1 macros to be GUILE_PROC, GUILE_PROC1 (may change names
later, but was useful to keep old versions around while migrate)
that has docstrings and argument lists embedded in the GUILE_PROC
macro invocations that expand into a function header. Use lots of
new SCM_VALIDATE_* macros to simplify error checking and reduce
tons of redundancy. This is very similar to what I did for Scwm.
Note that none of the extraction of the docstrings, nor software
engineering checks of Scwm is yet added to Guile. I'll work on
that tomorrow, I expect.
* Makefile.am: Added scm_validate.h to modinclude_HEADERS.
* chars.c: Added docstrings for the primitives defined in here.
* snarf.h: Added GUILE_PROC, GUILE_PROC1. Added
SCM_REGISTER_PROC to be like old SCM_PROC, though old SCM_PROC
still remains for now. Changed naming convention for the s_foo
string name of the primitive to be s_scm_foo for ease of use with
the macro.
* scm_validate.h: Lots of new SCM_VALIDATE macros to simplify
argument checking through guile. Maybe some of these should be
folded into the header file for the types they check, but for now
it was easiest to just stick them all in one place.
newline. A bit faster, and definitely hairier.
(scm_read_line): Count newlines here instead.
* strings.c (scm_take_str): New function.
(scm_take0str): Reimplement in terms of scm_take_str. * strings.h
(scm_take_str): New declaration. * ioext.c (scm_read_line): Use
scm_take_str, to avoid copying the string.
Add some simple-minded support for line buffered ports.
* ports.h (SCM_BUFLINE): New flag for ports.
* init.c (scm_init_standard_ports): Request line-buffering on
the standard output port.
* * ports.c (scm_mode_bits): Recognize 'l' as a request for line
buffering.
(scm_putc, scm_puts, scm_lfwrite): If the port is line-buffered,
and there's a newline to be written, flush the port.
* ports.c: (scm_lseek): clear buffers even if just reading current
position.
* fports.c (local_fclose): call local_fflush unconditionally.
(various): don't use the scm_must... memory procs.
* ports.h (scm_port): make read_pos a pointer to const.
strports.c: take care of rw_active and rw_randow.
fports.c: scm_fport_drain_input: removed. do it all in ports.c.
strports.c (scm_mkstrport): check that pos is reasonable.
ioext.c (scm_ftell, scm_fseek): use lseek.
(SCM_CLEAR_BUFFERS): macro deleted.
ioext.c (redirect_port: use ptob fflush, read_flush.
ports.h (scm_ptobfuns): add ftruncate.
ports.c (scm_newptob): set ftruncate.
adjust ptob tables.
* ports.c (scm_ftruncate): new procedure.
fports.c (local_ftrunate), strports.c (str_ftruncate): new procs.
strports.c (st_seek, st_grow_port): new procs.
fports.h (scm_port): change size types from int to off_t.
ports.c (scm_init_ports): initialise the seek symbols here
instead of in ioext.c.
strports.c (scm_call_with_output_string): start with an empty
string, so seek and ftruncate can be used.
* ports.h (scm_ptobfuns): add a read_flush procedure which is the
equivalent to fflush for the read buffer.
* ports.c (scm_newptob): set read_flush.
ports.c (void_port_ptob): set read_flush.
fports.c (local_read_flush): new proc. add to ptob.
strport.c (st_read_flush): likewise.
vport.c (sf_read_flush): likewise.
fports.h (struct scm_fport): remove random member. there's nothing
left but fdes. leaving it as a struct to allow for future changes.
fports.c: replace usage of scm_fport::random with scm_port::rw_random.
ports.c: (scm_putc, scm_puts, scm_lfwrite): call the read_flush
ptob proc if the read buffer is filled.
* ports.h (scm_port): add a rw_random member and replace
reading and writing members with rw_active member.
SCM_PORT_READ/SCM_PORT_WRITE: new values.
* ports.h (struct scm_port_table): add writing and reading members
to replace write_needs_seek: it isn't good enough for non-fports.
ports.c, ioext.c, fports.c: corresponding changes.
(struct scm_port_table): give it a typedef and rename to scm_port.
ports.c, fports.c, strports.c, vports.c, ioext.c, ports.h:
corresponding changes.
* ports.c (scm_newptob): bugfix: set seek member.
* * (scm_lseek): new procedure, using code from ioext.c:scm_fseek
and generalised to all port types.
* scmsigs.c (scm_init_scmsigs): set the SA_RESTART flag for all
signals (it was only being done for handlers installed from Scheme).
Otherwise (for example) SIGSTOP followed by SIGCONT on an interpreter
waiting for input caused an EINTR error from read.
* ports.h (struct scm_port_table): make all the char members
unsigned, so they convert to int without becoming negative if large.
* fports.c (scm_fdes_wait_for_input): forgot to check compilation
with threads enabled. rename this procedure to
fport_wait_for_input and take a port instead of a fdes.
use scm_fport_input_waiting_p instead of scm_fdes_waiting_p.
* readline.c (scm_readline): Applied a patch from Greg Harvey to
get readline support working again: use fdopen to get FILE objects.
* gc.c (scm_init_storage): install an atexit proc to flush the
ports.
(cleanup): the new proc. it sets a global variable which can be
checked by the ptob flush procs to avoid trying to throw
exceptions during exit. not very pleasant but it seems more reliable.
* fports.c (local_fflush): check terminating variable and if set
don't throw exception.
* CHECKME: that the atexit proc is installed if unexec used.
* throw.c (scm_handle_by_message): don't flush all ports here.
it still causes bus errors.
* fports.h (SCM_FPORT_CLEAR_BUFFERS): rename to SCM_CLEAR_BUFFERS
and move to ioext.c.
* fports.c (scm_fdes_waiting_p): merged into fport_input_waiting_p.
* ports.c (scm_char_ready_p): check the port buffer and call the
ptob entry if needed.
* ports.h (scm_ptobfuns): input_waiting_p added. change all the
ptob initialisers. use it in char-ready
* ioext.c (scm_do_read_line): moved from ports.c. make it static.
* vports.c (sfflush): modified to write a char (since softports
currently use shortbuf.)
* fports.c (scm_standard_stream_to_port): moved to init.c and
made static.
* init.c (scm_init_standard_ports): make stdout and stderr
unbuffered if connected to a terminal. with stdio they
were line-buffered by default.
* ports.h (scm_ptobfuns): change fflush return to void.
change flush proc definitions.
* strports.c (scm_call_with_output_string): get size from
buffer instead of port stream.
(scm_strprint_obj): likewise.
(st_flush): new proc.
* ports.h (struct scm_port_table): added write_end member,
as an optimisation. set it where write_buf_size is set.
* ports.h (struct scm_port_table): change stream from void *
back to SCM. SCM presumably must be large enough to hold a
pointer (and probably vice versa but who knows.)
(SCM_SSTREAM): deleted. change users back to SCM_STREAM.
(scm_puts): rewritten
* fports.c (local_ffwrite, local_fputs): removed.
* strports.c (stputc, stputs, stwrite): dyked out (FIXME)
* vports.c (sfputc, sfputs, sfwrite) likewise.
* ports.c (write_void_port, puts_void_port): removed.
(putc_void_port, getc_void_port, fgets_void_port): likewise.
* ports.c (scm_lfwrite): rewritten using fport.c version.
* fports.c (local_fputc): deleted.
* ports.c (scm_add_to_port_table): initialise write_needs_seek.
* ports.h (scm_ptobfuns): add seek function pointer.
* fports.c: set it to local_seek, new procedure.
* fports.h (SCM_MAYBE_DRAIN_INPUT): moved to ports.c.
use ptob for seek. take ptob instead of fport arg.
* ports.h (struct scm_port_table): new member write_needs_seek,
replaces reading member in fport struct.
* vports.c (sfgetc): store the getted char into the buffer.
rename to sf_fill_buffer and install it for fill-buffer in ptob.
the Scheme interface is still a procedure that gets a char.
(scm_make_soft_port): set up the port buffer (shortbuf).
* fports.c (local_fgetc, local_fgets): deleted.
* strports.c (stgetc): likewise.
* ports.c: scm_generic_fgets: likewise.
* ports.h (scm_ptobfuns): add fill_buffer.
* ports.c (scm_newptob): assign it.
* strports.c (scm_mkstrport): set up the buffer.
put just the string into the stream, not cons (pos stream).
(stfill_buffer): new proc.
* ports.h: fport buffer moved into port table: to be
used for all port types.
* throw.c (scm_handle_by_message): flush ports at exit.
* socket.c (scm_sock_fd_to_port): use scm_fdes_to_port.
(scm_getsockopt, scm_setsockopt, scm_shutdown, scm_connect,
scm_bind, scm_listen, scm_accept, scm_getsockname,
scm_getpeername, scm_recv, scm_send, scm_recvfrom,
scm_sendto,
use SCM_FPORT_FDES. use SCM_OPFPORTP not SCM_FPORTP.
* posix.c (scm_getgroups): use SCM_ALLOW/DEFER_INTS.
(scm_ttyname): use SCM_FPORT_FDES.
(scm_tcgetpgrp, scm_tcsetpgrp): likewise.
* ioext.c (scm_isatty_p): use SCM_FPORT_FDES.
(scm_fdes_to_ports): modified.
(scm_fdopen): use scm_fdes_to_port.
* ports.c (scm_init_ports): don't try to flush ports using
atexit(). it's too late, errors will cause SEGV.
* fports.c (scm_fport_buffer_add): new procedure.
* fports.h (SCM_FDES_RANDOM_P): new macro. use it in
scm_fdes_to_port and scm_redirect_port.
* ioext.c (scm_redirect_port): use setvbuf to set buffers in the
new port. reset fp->random.
* fports.c (scm_fdes_to_port), ports.c (scm_void_port),
filesys.c (scm_opendir):
restore defer interrupts while the port is constructed.
* (scm_setvbuf): if mode is _IOFBF and size is not supplied,
derive buffer size from fdes or use a default.
(scm_fdes_to_port): use setvbuf instead of creating the buffers
directly.
vports.c (various places): use SCM_SSTREAM.
strports.c: likewise.
* gdbint.c: likewise.
* ports.h (SCM_SSTREAM): new macro.
* fports.c (scm_input_waiting_p): use scm_return_first, since port
may be removed from the stack by the tail call to scm_fdes_waiting_p.
* fports.h (SCM_CLEAR_BUFFERS): new macro.
* ports.c (scm_force_output): call scm_fflush.
* print.c (scm_newline): don't check errno for EPIPE (it wouldn't
* reach this point.) don't flush port (if scm_cur_outp).
* fports.h (SCM_FPORT_FDES): new macro.
* vports.c (sfflush): don't need to set errno.
* ports.c: install scm_flush_all_ports to be run on exit.
ports.c fports.c ioext.c posix.c socket.c net_db.c filesys.c:
removed all uses of SCM_DEFER/ALLOW ints for now. they were mainly
just protecting errno. some may need to be put back.
* scmsigs.c (take_signal): save and restore errno while this
proc runs.
*fports.c (print_pipe_port, local_pclose, scm_pipob): deleted.
* open-pipe, close-pipe are emulated in (ice-9 popen)
ports.c (scm_ports_prehistory): don't init scm_pipob.
ports.h (scm_tc16_pipe): deleted.
posix.c (scm_open_pipe, scm_close_pipe): deleted.
* ioext.c (scm_primitive_move_to_fdes): use fport.
* fport.c (scm_fport_fill_buffer): flush write buffer if needed.
change arg type from scm_fport to SCM port.
fport.h (SCM_SETFDES): removed.
(SCM_MAYBE_DRAIN_INPUT): new macro.
* ioext.c (scm_dup_to_fdes): use SCM_FSTREAM.
(scm_ftell): always use lseek and account for the buffer.
(scm_fileno): use fport buffer.
(scm_fseek): clear fport buffers. always use lseek.
* posix.c (scm_pipe): use fport buffer.
* unif.c: include fports.h instead of genio.h.
* fports.c (scm_fdes_wait_for_input, scm_fport_fill_buffer): new
procedures.
(local_fgetc): use them.
(local_ffwrite): use buffer.
(local_fgets): use buffer.
(scm_setbuf0): deleted.
(scm_setvbuf): set the buffer.
(scm_setfileno): deleted.
(scm_evict_ports): set fdes directly.
* (scm_freopen): deleted. doesn't seem useful in Guile.
(scm_stdio_to_port): deleted.
fports.h (struct scm_fport): add shortbuf member to avoid separate
code for unbuffered ports.
(SCM_FPORTP, SCM_OPFPORTP, SCM_OPINFPORTP, SCM_OPOUTFPORTP): moved
from ports.h.
* genio.c, genio.h: move contents into ports.c, ports.h. The
division wasn't useful.
* fports.c, fports.h (scm_fport_drain_input): new procedure.
* ports.c (scm_drain_input): call scm_fport_drain_input.
* scm_fdes_waiting_p: new procedure.
* fports.c (scm_fdes_to_port): allocate read and/or write buffers.
(scm_input_waiting_p): check the buffer.
(local_fgetc, local_fflush, local_fputc): likewise.
* fports.h (scm_fport): read/write_buf,_pos,_buf_end,,_buf_size:
new members.
* init.c (scm_init_standard_ports): pass fdes instead of FILE *.
* * ports.c (scm_drain_input): new procedure.
ports.h: prototype.
* fports.c (FPORT_READ_SAFE, FPORT_WRITE_SAFE, FPORT_ALL_OKAY,
pre_read, pre_write): removed.
(local_fputc, local_fputs, local_ffwrite): use write, not stdio.
(scm_standard_stream_to_port): change first arg from FILE * to
int fdes.
(local_fflush): flush fdes, not FILE *.
* fports.h (SCM_NOFTELL): removed.
* genio.c, ports.c: don't include filesys.h.
* genio.c (scm_getc): don't use scm_internal_select if FPORT.
do it in fports.c:local_fgetc.
* genio.c: don't use SCM_SYSCALL when calling ptob procedures.
do it where it's needed in the port smobs.
* filesys.c (scm_input_waiting_p): moved to fports.c, stdio
buffer support removed. take SCM arg, not FILE *.
* filesys.h: prototype moved too.
* fports.c (scm_fdes_to_port): new procedure.
(local_fgetc): use read not fgetc.
(local_fclose): use close, not fclose.
(local_fgets): use read, not fgets
* fports.h: prototype for scm_fdes_to_port.
* fports.h (scm_fport): new struct.
* fports.c (scm_open_file): use open, not fopen.
#include fcntl.h
* ports.h (struct scm_port_table): change stream from SCM to void *.
* ports.c (scm_add_to_port_table): check for memory allocation error.
(scm_prinport): remove MSDOS hair.
(scm_void_port): set stream to 0 instead of SCM_BOOL_F.
(scm_close_port): don't throw errors: do it in fports.c.
* init.c (scm_boot_guile_1): Use scm_internal_lazy_catch, so the
stack is still there when we catch the error.
* throw.c (handler_message): If we are handling an error with a
message, then put together the proper arguments and call
scm_display_error, instead of scm_display_error_message. That
displays source location, if it can find it.
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.
throw.c (scm_internal_stack_catch): New sibling to the other catch
functions. Code moved from gh_eval.c.
throw.h: Added header.
gh_eval.c (gh_eval_str_with_stack_saving_handler): Renamed call to
scm_internal_stack_catch.
After all the Scheme handler function might signal an error too,
and we don't want to lose that.
(cwdr_inner_body): Renamed from cwdr_body.
(cwdr_outer_body): New function, to establish the user's handler,
and pass control to cwdr_inner_body.
(cwdr): Establish the reliable catch-all handler here, and pass
control to cwdr_outer_body.
(struct cwdr_body_data): New field, handler, to allow cwdr to pass
the user's handler through to cwdr_outer_body.
* throw.c (scm_handle_by_message): Move guts into....
(handler_message): New static function.
(scm_handle_by_message_noexit): New function.
* throw.h (scm_handle_by_message_noexit): New prototype.
gdb_interface.h, gdbint.c, gdbint.h, gh_data.c, gh_init.c,
gh_io.c, gh_list.c, gh_predicates.c, gh_test_c.c, gh_test_repl.c,
init.c, net_db.c, options.c, options.h, ports.c, print.c, read.c,
script.h, snarf.h, srcprop.c, srcprop.h, stacks.c, stacks.h,
throw.c: Update copyright years; these files have been worked on
significantly in 1997, but only had copyright years for 1996.
Also, change name of copyright holder on some from Mikael
Djurfeldt to Free Software Foundation; he has signed papers
assigning the changes to the FSF.
* throw.c (scm_handle_by_message): if a 'quit is caught, use its
args to derive an exit status. Allows (quit) to work from a
script.
(scm_exit_status): new function.
#include "eq.h".
1. mark_lazy_catch didn't mark the smob.
2. Both functions above have standard variants:
(lazy_catch_funs): Changed mark_lazy_catch --> scm_mark0,
free_lazy_catch --> scm_free0.
(scm_lazy_catch): Rewritten to use it.
(scm_ithrow): Handle the new lazy catch representation.
Use SCM_LAZY_CATCH_P, instead of assuming that any wind list entry
that doesn't have a jmpbuf is a lazy catch clause.
(tc16_lazy_catch, struct lazy_catch, mark_lazy_catch,
free_lazy_catch, print_lazy_catch, lazy_catch_funs,
make_lazy_catch, SCM_LAZY_CATCH_P): Support funs, including a new
smob.
(scm_init_throw): Register the new lazy-catch smob type.
* throw.h (scm_internal_lazy_catch): decl for new function.
* throw.c (scm_internal_catch): Doc fixes.
apparent unportability of forward declarations of static arrays of
the form `static foo bar[];'.
* ramap.c (scm_array_fill_x): Moved above scm_array_fill_int.
(ra_rpsubrs, ra_asubrs): Moved to the top of array code.
* throw.c (scm_throw): Moved above scm_ithrow.
* options.h: Removed the extern declarations of scm_yes_sym and
scm_no_sym since these are static.
use separate data pointers, to allow them to be designed
independently and reused.
(scm_body_thunk, scm_handle_by_proc, scm_handle_by_message):
Renamed from catch_body, catch_handler, and uncaught_throw; made
generically useful.
(struct scm_catch_body_data): Renamed from catch_body_data; moved
to throw.h.
(scm_catch): Use the above.
(scm_throw): Don't bother printing a message for an uncaught
throw; we establish a default handler in init.
* throw.h (scm_internal_catch): Prototype updated.
(scm_body_thunk, scm_handle_by_proc, scm_handle_by_message): New
decls.
(struct scm_body_thunk_data): New structure, used as data
argument to scm_body_thunk.
* init.c (struct main_func_closure): New structure, packaging up
the data to pass to the user's main function.
(scm_boot_guile): Create one. Pass it to scm_boot_guile_1.
(scm_boot_guile_1): Pass it through to invoke_main_func. Use
scm_internal_catch to establish a catch-all handler, using
scm_handle_by_message. This replaces the special-case code in
scm_throw.
(invoke_main_func): Body function for scm_internal_catch; invoke
the user's main function, using the main_func_closure pointer to
decide what to pass it.
* root.c (struct cwdr_body_data): Remove handler_proc member.
(cwdr): Use scm_handle_by_proc instead of cwdr_handler.
(cwdr_handler): Removed.
figure that out; this usually happens when one variable is only
initialized and used when a particular condition holds true, and
we know that condition will never change within a given invocation
of the function. In this case, we simply initialize the variables
to placate the compiler, hopefully to a value which will cause a
crash if it is ever actually used.
* print.c (scm_iprin1): Initialize mw_pos.
* read.c (scm_lreadrecparen): Initialize tl2, ans2.
* throw.c (scm_ithrow): Initialize dynpair.
* unif.c (scm_uniform_vector_ref): Initialize cra.
* struct.c (init_struct): Initialize prot.
* mbstrings.c (scm_print_mb_symbol): Initialize mw_pos and inc.
Scheme.
* throw.h (scm_catch_body_t, scm_catch_handler_t): New types.
(scm_internal_catch): New function, replaces...
(scm_catch_apply): Deleted.
* throw.c (scm_catch_apply): Deleted; replaced with a more general
mechanism which is a bit more code, but can be used nicely from C
and implement the Scheme semantics as well.
(scm_internal_catch): This is the replacement; it's named after
the analogous function in Emacs.
(scm_catch): Reimplemented in terms of the above.
(struct catch_body_data, catch_body, catch_handler): New
functions, used by scm_catch.
* root.c (cwdr): Reimplemented in terms of scm_internal_catch.
(struct cwdr_body_data, cwdr_body, cwdr_handler): New functions;
support for new cwdr.
srcprop.h, tags.h, throw.c, unif.c: Added new selectors
SCM_SETAND_CAR, SCM_SETAND_CDR, SCM_SETOR_CAR and SCM_SETOR_CDR.
Motivation: Safer use. Some other macros are defined in terms of
these operations. If these are defined using the SCM_SETCXR
(<e1>, SCM_CXR (<e1>) <op> <e2>) pattern a complex <e1> will lead
to inefficiency and an <e1> with side-effects could potentially
break. Also, these particular operations are heavily utilized in
the garbage collector. In unoptimized code there will be a
measurable speedup.
* alist.c, arbiters.c, continuations.c, debug.c, debug.h, eval.c,
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.)
throw.c: Renamed last_debug_info_frame -> scm_last_debug_frame.
* throw.c: Renamed scm_catch --> scm_catch_apply and added more
arguments. The motivation is that code in root.c needs catch
functionality, and we want to avoid code duplication.
New functions: scm_catch, scm_lazy_catch. These are wrappers for
scm_catch_apply. scm_lazy_catch is intended to introduce catch
handlers that run without popping the stack into the dynwind
chain.
see if a given element of scm_dynwinds is a valid catch.
* throw.c (scm_ithrow): If scm_dynwinds has invalid list
structure, abort; don't just silently ignore the garbage.
(scm_catch): Changed SCM_DEFER_INTS --> SCM_REDEFER_INTS and
SCM_ALLOW_INTS --> SCM_REALLOW_INTS. This is so that scm_catch
can be used in scm_call_with_new_root; Added reenabling of stack
checking when catching a throw.
Remove special support for uncaught throws; see throw.c for
rationale.
* throw.c (unhandled_throw): New function.
(scm_ithrow): Call unhandled_throw if we don't find a throw
target; don't mess with scm_bad_throw_vcell.
(scm_bad_throw_vcell): Variable deleted.
(scm_init_throw): Don't initialize it.
* throw.c (scm_ithrow): Don't let outer key matches shadow inner
#t catches.
