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1/***********************************************/
2/* Global only to current interpreter instance */
3/***********************************************/
4
5/* Don't forget to re-run embed.pl to propagate changes! */
6
7/* New variables must be added to the very end for binary compatibility.
8 * XSUB.h provides wrapper functions via perlapi.h that make this
9 * irrelevant, but not all code may be expected to #include XSUB.h. */
10
11/* Don't forget to add your variable also to perl_clone()! */
12
13/* The 'I' prefix is only needed for vars that need appropriate #defines
14 * generated when built with or without MULTIPLICITY. It is also used
15 * to generate the appropriate export list for win32.
16 *
17 * When building without MULTIPLICITY, these variables will be truly global. */
18
19/* pseudo environmental stuff */
20PERLVAR(Iorigargc, int)
21PERLVAR(Iorigargv, char **)
22PERLVAR(Ienvgv, GV *)
23PERLVAR(Iincgv, GV *)
24PERLVAR(Ihintgv, GV *)
25PERLVAR(Iorigfilename, char *)
26PERLVAR(Idiehook, SV *)
27PERLVAR(Iwarnhook, SV *)
28
29/* switches */
30PERLVAR(Iminus_c, bool)
31PERLVAR(Ipatchlevel, SV *)
32PERLVAR(Ilocalpatches, const char * const *)
33PERLVARI(Isplitstr, const char *, " ")
34PERLVAR(Ipreprocess, bool)
35PERLVAR(Iminus_n, bool)
36PERLVAR(Iminus_p, bool)
37PERLVAR(Iminus_l, bool)
38PERLVAR(Iminus_a, bool)
39PERLVAR(Iminus_F, bool)
40PERLVAR(Idoswitches, bool)
41PERLVAR(Iminus_E, bool)
42
43/*
44=head1 Global Variables
45
46=for apidoc mn|bool|PL_dowarn
47
48The C variable which corresponds to Perl's $^W warning variable.
49
50=cut
51*/
52
53PERLVAR(Idowarn, U8)
54PERLVAR(Iwidesyscalls, bool) /* unused since 5.8.1 */
55PERLVAR(Idoextract, bool)
56PERLVAR(Isawampersand, bool) /* must save all match strings */
57PERLVAR(Iunsafe, bool)
58PERLVAR(Iinplace, char *)
59PERLVAR(Ie_script, SV *)
60PERLVAR(Iperldb, U32)
61
62/* This value may be set when embedding for full cleanup */
63/* 0=none, 1=full, 2=full with checks */
64PERLVARI(Iperl_destruct_level, int, 0)
65
66/* magical thingies */
67PERLVAR(Ibasetime, Time_t) /* $^T */
68PERLVAR(Iformfeed, SV *) /* $^L */
69
70
71PERLVARI(Imaxsysfd, I32, MAXSYSFD)
72 /* top fd to pass to subprocesses */
73PERLVAR(Imultiline, int) /* $*--do strings hold >1 line? */
74PERLVAR(Istatusvalue, I32) /* $? */
75PERLVAR(Iexit_flags, U8) /* was exit() unexpected, etc. */
76#ifdef VMS
77PERLVAR(Istatusvalue_vms,U32)
78#else
79PERLVAR(Istatusvalue_posix,I32)
80#endif
81
82/* shortcuts to various I/O objects */
83PERLVAR(Istdingv, GV *)
84PERLVAR(Istderrgv, GV *)
85PERLVAR(Idefgv, GV *)
86PERLVAR(Iargvgv, GV *)
87PERLVAR(Iargvoutgv, GV *)
88PERLVAR(Iargvout_stack, AV *)
89
90/* shortcuts to regexp stuff */
91/* this one needs to be moved to thrdvar.h and accessed via
92 * find_threadsv() when USE_5005THREADS */
93PERLVAR(Ireplgv, GV *)
94
95/* shortcuts to misc objects */
96PERLVAR(Ierrgv, GV *)
97
98/* shortcuts to debugging objects */
99PERLVAR(IDBgv, GV *)
100PERLVAR(IDBline, GV *)
101
102/*
103=for apidoc mn|GV *|PL_DBsub
104When Perl is run in debugging mode, with the B<-d> switch, this GV contains
105the SV which holds the name of the sub being debugged. This is the C
106variable which corresponds to Perl's $DB::sub variable. See
107C<PL_DBsingle>.
108
109=for apidoc mn|SV *|PL_DBsingle
110When Perl is run in debugging mode, with the B<-d> switch, this SV is a
111boolean which indicates whether subs are being single-stepped.
112Single-stepping is automatically turned on after every step. This is the C
113variable which corresponds to Perl's $DB::single variable. See
114C<PL_DBsub>.
115
116=for apidoc mn|SV *|PL_DBtrace
117Trace variable used when Perl is run in debugging mode, with the B<-d>
118switch. This is the C variable which corresponds to Perl's $DB::trace
119variable. See C<PL_DBsingle>.
120
121=cut
122*/
123
124PERLVAR(IDBsub, GV *)
125PERLVAR(IDBsingle, SV *)
126PERLVAR(IDBtrace, SV *)
127PERLVAR(IDBsignal, SV *)
128PERLVAR(Ilineary, AV *) /* lines of script for debugger */
129PERLVAR(Idbargs, AV *) /* args to call listed by caller function */
130
131/* symbol tables */
132PERLVAR(Idebstash, HV *) /* symbol table for perldb package */
133PERLVAR(Iglobalstash, HV *) /* global keyword overrides imported here */
134PERLVAR(Icurstname, SV *) /* name of current package */
135PERLVAR(Ibeginav, AV *) /* names of BEGIN subroutines */
136PERLVAR(Iendav, AV *) /* names of END subroutines */
137PERLVAR(Icheckav, AV *) /* names of CHECK subroutines */
138PERLVAR(Iinitav, AV *) /* names of INIT subroutines */
139PERLVAR(Istrtab, HV *) /* shared string table */
140PERLVARI(Isub_generation,U32,1) /* incr to invalidate method cache */
141
142/* memory management */
143PERLVAR(Isv_count, I32) /* how many SV* are currently allocated */
144PERLVAR(Isv_objcount, I32) /* how many objects are currently allocated */
145PERLVAR(Isv_root, SV*) /* storage for SVs belonging to interp */
146PERLVAR(Isv_arenaroot, SV*) /* list of areas for garbage collection */
147
148/* funky return mechanisms */
149PERLVAR(Iforkprocess, int) /* so do_open |- can return proc# */
150
151/* subprocess state */
152PERLVAR(Ifdpid, AV *) /* keep fd-to-pid mappings for my_popen */
153
154/* internal state */
155PERLVAR(Itainting, bool) /* doing taint checks */
156PERLVARI(Iop_mask, char *, NULL) /* masked operations for safe evals */
157
158/* current interpreter roots */
159PERLVAR(Imain_cv, CV *)
160PERLVAR(Imain_root, OP *)
161PERLVAR(Imain_start, OP *)
162PERLVAR(Ieval_root, OP *)
163PERLVAR(Ieval_start, OP *)
164
165/* runtime control stuff */
166PERLVARI(Icurcopdb, COP *, NULL)
167PERLVARI(Icopline, line_t, NOLINE)
168
169/* statics moved here for shared library purposes */
170PERLVAR(Ifilemode, int) /* so nextargv() can preserve mode */
171PERLVAR(Ilastfd, int) /* what to preserve mode on */
172PERLVAR(Ioldname, char *) /* what to preserve mode on */
173PERLVAR(IArgv, char **) /* stuff to free from do_aexec, vfork safe */
174PERLVAR(ICmd, char *) /* stuff to free from do_aexec, vfork safe */
175PERLVARI(Igensym, I32, 0) /* next symbol for getsym() to define */
176PERLVAR(Ipreambled, bool)
177PERLVAR(Ipreambleav, AV *)
178PERLVARI(Ilaststatval, int, -1)
179PERLVARI(Ilaststype, I32, OP_STAT)
180PERLVAR(Imess_sv, SV *)
181
182/* XXX shouldn't these be per-thread? --GSAR */
183PERLVAR(Iors_sv, SV *) /* output record separator $\ */
184
185/* interpreter atexit processing */
186PERLVARI(Iexitlist, PerlExitListEntry *, NULL)
187 /* list of exit functions */
188PERLVARI(Iexitlistlen, I32, 0) /* length of same */
189
190/*
191=for apidoc Amn|HV*|PL_modglobal
192
193C<PL_modglobal> is a general purpose, interpreter global HV for use by
194extensions that need to keep information on a per-interpreter basis.
195In a pinch, it can also be used as a symbol table for extensions
196to share data among each other. It is a good idea to use keys
197prefixed by the package name of the extension that owns the data.
198
199=cut
200*/
201
202PERLVAR(Imodglobal, HV *) /* per-interp module data */
203
204/* these used to be in global before 5.004_68 */
205PERLVARI(Iprofiledata, U32 *, NULL) /* table of ops, counts */
206PERLVARI(Irsfp, PerlIO * VOL, Nullfp) /* current source file pointer */
207PERLVARI(Irsfp_filters, AV *, NULL) /* keeps active source filters */
208
209PERLVAR(Icompiling, COP) /* compiling/done executing marker */
210
211PERLVAR(Icompcv, CV *) /* currently compiling subroutine */
212PERLVAR(Icomppad, AV *) /* storage for lexically scoped temporaries */
213PERLVAR(Icomppad_name, AV *) /* variable names for "my" variables */
214PERLVAR(Icomppad_name_fill, I32) /* last "introduced" variable offset */
215PERLVAR(Icomppad_name_floor, I32) /* start of vars in innermost block */
216
217#ifdef HAVE_INTERP_INTERN
218PERLVAR(Isys_intern, struct interp_intern)
219 /* platform internals */
220#endif
221
222/* more statics moved here */
223PERLVARI(Igeneration, int, 100) /* from op.c */
224PERLVAR(IDBcv, CV *) /* from perl.c */
225
226PERLVARI(Iin_clean_objs,bool, FALSE) /* from sv.c */
227PERLVARI(Iin_clean_all, bool, FALSE) /* from sv.c */
228
229PERLVAR(Ilinestart, char *) /* beg. of most recently read line */
230PERLVAR(Ipending_ident, char) /* pending identifier lookup */
231PERLVAR(Isublex_info, SUBLEXINFO) /* from toke.c */
232
233PERLVAR(Iuid, Uid_t) /* current real user id */
234PERLVAR(Ieuid, Uid_t) /* current effective user id */
235PERLVAR(Igid, Gid_t) /* current real group id */
236PERLVAR(Iegid, Gid_t) /* current effective group id */
237PERLVAR(Inomemok, bool) /* let malloc context handle nomem */
238PERLVARI(Ian, U32, 0) /* malloc sequence number */
239PERLVARI(Icop_seqmax, U32, 0) /* statement sequence number */
240PERLVARI(Ievalseq, U32, 0) /* eval sequence number */
241PERLVAR(Iorigenviron, char **)
242PERLVAR(Iorigalen, U32)
243#ifdef PERL_USES_PL_PIDSTATUS
244PERLVAR(Ipidstatus, HV *) /* pid-to-status mappings for waitpid */
245#endif
246PERLVARI(Imaxo, int, MAXO) /* maximum number of ops */
247PERLVAR(Iosname, char *) /* operating system */
248
249PERLVAR(Isighandlerp, Sighandler_t)
250
251PERLVARA(Ibody_roots, SVt_LAST, void*) /* array of body roots */
252
253PERLVAR(Inice_chunk, char *) /* a nice chunk of memory to reuse */
254PERLVAR(Inice_chunk_size, U32) /* how nice the chunk of memory is */
255
256PERLVARI(Irunops, runops_proc_t, MEMBER_TO_FPTR(RUNOPS_DEFAULT))
257
258PERLVARA(Itokenbuf,256, char)
259
260/*
261=for apidoc Amn|SV|PL_sv_undef
262This is the C<undef> SV. Always refer to this as C<&PL_sv_undef>.
263
264=for apidoc Amn|SV|PL_sv_no
265This is the C<false> SV. See C<PL_sv_yes>. Always refer to this as
266C<&PL_sv_no>.
267
268=for apidoc Amn|SV|PL_sv_yes
269This is the C<true> SV. See C<PL_sv_no>. Always refer to this as
270C<&PL_sv_yes>.
271
272=cut
273*/
274
275PERLVAR(Isv_undef, SV)
276PERLVAR(Isv_no, SV)
277PERLVAR(Isv_yes, SV)
278
279#ifdef CSH
280PERLVARI(Icshname, const char *, CSH)
281PERLVARI(Icshlen, I32, 0)
282#endif
283
284PERLVAR(Ilex_state, U32) /* next token is determined */
285PERLVAR(Ilex_defer, U32) /* state after determined token */
286PERLVAR(Ilex_expect, int) /* expect after determined token */
287PERLVAR(Ilex_brackets, I32) /* bracket count */
288PERLVAR(Ilex_formbrack, I32) /* bracket count at outer format level */
289PERLVAR(Ilex_casemods, I32) /* casemod count */
290PERLVAR(Ilex_dojoin, I32) /* doing an array interpolation */
291PERLVAR(Ilex_starts, I32) /* how many interps done on level */
292PERLVAR(Ilex_stuff, SV *) /* runtime pattern from m// or s/// */
293PERLVAR(Ilex_repl, SV *) /* runtime replacement from s/// */
294PERLVAR(Ilex_op, OP *) /* extra info to pass back on op */
295PERLVAR(Ilex_inpat, OP *) /* in pattern $) and $| are special */
296PERLVAR(Ilex_inwhat, I32) /* what kind of quoting are we in */
297PERLVAR(Ilex_brackstack,char *) /* what kind of brackets to pop */
298PERLVAR(Ilex_casestack, char *) /* what kind of case mods in effect */
299
300/* What we know when we're in LEX_KNOWNEXT state. */
301PERLVARA(Inextval,5, YYSTYPE) /* value of next token, if any */
302PERLVARA(Inexttype,5, I32) /* type of next token */
303PERLVAR(Inexttoke, I32)
304
305PERLVAR(Ilinestr, SV *)
306PERLVAR(Ibufptr, char *)
307PERLVAR(Ioldbufptr, char *)
308PERLVAR(Ioldoldbufptr, char *)
309PERLVAR(Ibufend, char *)
310PERLVARI(Iexpect,int, XSTATE) /* how to interpret ambiguous tokens */
311
312PERLVAR(Imulti_start, I32) /* 1st line of multi-line string */
313PERLVAR(Imulti_end, I32) /* last line of multi-line string */
314PERLVAR(Imulti_open, I32) /* delimiter of said string */
315PERLVAR(Imulti_close, I32) /* delimiter of said string */
316
317PERLVAR(Ierror_count, I32) /* how many errors so far, max 10 */
318PERLVAR(Isubline, I32) /* line this subroutine began on */
319PERLVAR(Isubname, SV *) /* name of current subroutine */
320
321PERLVAR(Imin_intro_pending, I32) /* start of vars to introduce */
322PERLVAR(Imax_intro_pending, I32) /* end of vars to introduce */
323PERLVAR(Ipadix, I32) /* max used index in current "register" pad */
324PERLVAR(Ipadix_floor, I32) /* how low may inner block reset padix */
325PERLVAR(Ipad_reset_pending, I32) /* reset pad on next attempted alloc */
326
327PERLVAR(Ilast_uni, char *) /* position of last named-unary op */
328PERLVAR(Ilast_lop, char *) /* position of last list operator */
329PERLVAR(Ilast_lop_op, OPCODE) /* last list operator */
330PERLVAR(Iin_my, I32) /* we're compiling a "my" (or "our") declaration */
331PERLVAR(Iin_my_stash, HV *) /* declared class of this "my" declaration */
332#ifdef FCRYPT
333PERLVARI(Icryptseen, bool, FALSE) /* has fast crypt() been initialized? */
334#endif
335
336PERLVAR(Ihints, U32) /* pragma-tic compile-time flags */
337
338PERLVAR(Idebug, VOL U32) /* flags given to -D switch */
339
340PERLVARI(Iamagic_generation, long, 0)
341
342#ifdef USE_LOCALE_COLLATE
343PERLVARI(Icollation_ix, U32, 0) /* Collation generation index */
344PERLVAR(Icollation_name,char *) /* Name of current collation */
345PERLVARI(Icollation_standard, bool, TRUE)
346 /* Assume simple collation */
347PERLVAR(Icollxfrm_base, Size_t) /* Basic overhead in *xfrm() */
348PERLVARI(Icollxfrm_mult,Size_t, 2) /* Expansion factor in *xfrm() */
349#endif /* USE_LOCALE_COLLATE */
350
351#ifdef USE_LOCALE_NUMERIC
352
353PERLVAR(Inumeric_name, char *) /* Name of current numeric locale */
354PERLVARI(Inumeric_standard, bool, TRUE)
355 /* Assume simple numerics */
356PERLVARI(Inumeric_local, bool, TRUE)
357 /* Assume local numerics */
358
359PERLVAR(Inumeric_compat1, char)
360 /* Used to be numeric_radix */
361#endif /* !USE_LOCALE_NUMERIC */
362
363/* utf8 character classes */
364PERLVAR(Iutf8_alnum, SV *)
365PERLVAR(Iutf8_alnumc, SV *)
366PERLVAR(Iutf8_ascii, SV *)
367PERLVAR(Iutf8_alpha, SV *)
368PERLVAR(Iutf8_space, SV *)
369PERLVAR(Iutf8_cntrl, SV *)
370PERLVAR(Iutf8_graph, SV *)
371PERLVAR(Iutf8_digit, SV *)
372PERLVAR(Iutf8_upper, SV *)
373PERLVAR(Iutf8_lower, SV *)
374PERLVAR(Iutf8_print, SV *)
375PERLVAR(Iutf8_punct, SV *)
376PERLVAR(Iutf8_xdigit, SV *)
377PERLVAR(Iutf8_mark, SV *)
378PERLVAR(Iutf8_toupper, SV *)
379PERLVAR(Iutf8_totitle, SV *)
380PERLVAR(Iutf8_tolower, SV *)
381PERLVAR(Iutf8_tofold, SV *)
382PERLVAR(Ilast_swash_hv, HV *)
383PERLVAR(Ilast_swash_klen, U32)
384PERLVARA(Ilast_swash_key,10, U8)
385PERLVAR(Ilast_swash_tmps, U8 *)
386PERLVAR(Ilast_swash_slen, STRLEN)
387
388/* perly.c globals */
389PERLVAR(Iyycharp, int *)
390PERLVAR(Iyylvalp, YYSTYPE *)
391
392PERLVARI(Iglob_index, int, 0)
393PERLVAR(Isrand_called, bool)
394PERLVARA(Iuudmap,256, char)
395PERLVAR(Ibitcount, char *)
396
397PERLVAR(Ipsig_ptr, SV**)
398PERLVAR(Ipsig_name, SV**)
399
400#if defined(PERL_IMPLICIT_SYS)
401PERLVAR(IMem, struct IPerlMem*)
402PERLVAR(IMemShared, struct IPerlMem*)
403PERLVAR(IMemParse, struct IPerlMem*)
404PERLVAR(IEnv, struct IPerlEnv*)
405PERLVAR(IStdIO, struct IPerlStdIO*)
406PERLVAR(ILIO, struct IPerlLIO*)
407PERLVAR(IDir, struct IPerlDir*)
408PERLVAR(ISock, struct IPerlSock*)
409PERLVAR(IProc, struct IPerlProc*)
410#endif
411
412#if defined(USE_ITHREADS)
413PERLVAR(Iptr_table, PTR_TBL_t*)
414#endif
415PERLVARI(Ibeginav_save, AV*, NULL) /* save BEGIN{}s when compiling */
416
417PERLVAR(Ibody_arenas, void*) /* pointer to list of body-arenas */
418
419 /* 5.6.0 stopped here */
420
421PERLVAR(Ipsig_pend, int *) /* per-signal "count" of pending */
422PERLVARI(Isig_pending, int,0) /* Number if highest signal pending */
423
424#ifdef USE_LOCALE_NUMERIC
425
426PERLVAR(Inumeric_radix_sv, SV *) /* The radix separator if not '.' */
427
428#endif
429
430#if defined(USE_ITHREADS)
431PERLVAR(Iregex_pad, SV**) /* All regex objects */
432PERLVAR(Iregex_padav, AV*) /* All regex objects */
433
434#endif
435
436#ifdef USE_REENTRANT_API
437PERLVAR(Ireentrant_buffer, REENTR*) /* here we store the _r buffers */
438#endif
439
440PERLVARI(Isavebegin, bool, FALSE) /* save BEGINs for compiler */
441
442PERLVAR(Icustom_op_names, HV*) /* Names of user defined ops */
443PERLVAR(Icustom_op_descs, HV*) /* Descriptions of user defined ops */
444
445#ifdef PERLIO_LAYERS
446PERLVARI(Iperlio, PerlIO *,NULL)
447PERLVARI(Iknown_layers, PerlIO_list_t *,NULL)
448PERLVARI(Idef_layerlist, PerlIO_list_t *,NULL)
449#endif
450
451PERLVARI(Iencoding, SV*, NULL) /* character encoding */
452
453PERLVAR(Idebug_pad, struct perl_debug_pad) /* always needed because of the re extension */
454
455PERLVAR(Itaint_warn, bool) /* taint warns instead of dying */
456
457#ifdef PL_OP_SLAB_ALLOC
458PERLVAR(IOpPtr,I32 **)
459PERLVARI(IOpSpace,I32,0)
460PERLVAR(IOpSlab,I32 *)
461#endif
462
463PERLVAR(Iutf8locale, bool) /* utf8 locale detected */
464
465PERLVAR(Iutf8_idstart, SV *)
466PERLVAR(Iutf8_idcont, SV *)
467
468PERLVAR(Isort_RealCmp, SVCOMPARE_t)
469
470PERLVARI(Icheckav_save, AV*, NULL) /* save CHECK{}s when compiling */
471
472PERLVARI(Iclocktick, long, 0) /* this many times() ticks in a second */
473
474PERLVARI(Iin_load_module, int, 0) /* to prevent recursions in PerlIO_find_layer */
475
476PERLVAR(Iunicode, U32) /* Unicode features: $ENV{PERL_UNICODE} or -C */
477
478PERLVAR(Isignals, U32) /* Using which pre-5.8 signals */
479
480PERLVAR(Istashcache, HV *) /* Cache to speed up S_method_common */
481
482PERLVAR(Ireentrant_retint, int) /* Integer return value from reentrant functions */
483
484/* Hooks to shared SVs and locks. */
485PERLVARI(Isharehook, share_proc_t, MEMBER_TO_FPTR(Perl_sv_nosharing))
486PERLVARI(Ilockhook, share_proc_t, MEMBER_TO_FPTR(Perl_sv_nosharing))
487#ifdef NO_MATHOMS
488# define PERL_UNLOCK_HOOK Perl_sv_nosharing
489#else
490/* This reference ensures that the mathoms are linked with perl */
491# define PERL_UNLOCK_HOOK Perl_sv_nounlocking
492#endif
493PERLVARI(Iunlockhook, share_proc_t, MEMBER_TO_FPTR(PERL_UNLOCK_HOOK))
494
495PERLVARI(Ithreadhook, thrhook_proc_t, MEMBER_TO_FPTR(Perl_nothreadhook))
496
497/* Force inclusion of both runops options */
498PERLVARI(Irunops_std, runops_proc_t, MEMBER_TO_FPTR(Perl_runops_standard))
499PERLVARI(Irunops_dbg, runops_proc_t, MEMBER_TO_FPTR(Perl_runops_debug))
500
501/* Stores the PPID */
502#ifdef THREADS_HAVE_PIDS
503PERLVARI(Ippid, IV, 0)
504#endif
505
506PERLVARI(Ihash_seed, UV, 0) /* Hash initializer */
507
508PERLVARI(Ihash_seed_set, bool, FALSE) /* Hash initialized? */
509
510PERLVAR(IDBassertion, SV *)
511
512PERLVARI(Icv_has_eval, I32, 0) /* PL_compcv includes an entereval or similar */
513
514PERLVARI(Irehash_seed, UV, 0) /* 582 hash initializer */
515
516PERLVARI(Irehash_seed_set, bool, FALSE) /* 582 hash initialized? */
517
518#ifdef DEBUG_LEAKING_SCALARS_FORK_DUMP
519/* File descriptor to talk to the child which dumps scalars. */
520PERLVARI(Idumper_fd, int, -1)
521#endif
522
523#ifdef PERL_IMPLICIT_CONTEXT
524PERLVARI(Imy_cxt_size, int, 0) /* size of PL_my_cxt_list */
525PERLVARI(Imy_cxt_list, void **, NULL) /* per-module array of MY_CXT pointers */
526#endif
527
528/* New variables must be added to the very end, before this comment,
529 * for binary compatibility (the offsets of the old members must not change).
530 * (Don't forget to add your variable also to perl_clone()!)
531 * XSUB.h provides wrapper functions via perlapi.h that make this
532 * irrelevant, but not all code may be expected to #include XSUB.h.
533 */