summaryrefslogtreecommitdiff
path: root/pad.c
blob: 06cadbb25905da2a6c9742c8d8f298ede054ad70 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
/*    pad.c
 *
 *    Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008
 *    by Larry Wall and others
 *
 *    You may distribute under the terms of either the GNU General Public
 *    License or the Artistic License, as specified in the README file.
 */

/*
 *  'Anyway: there was this Mr. Frodo left an orphan and stranded, as you
 *   might say, among those queer Bucklanders, being brought up anyhow in
 *   Brandy Hall.  A regular warren, by all accounts.  Old Master Gorbadoc
 *   never had fewer than a couple of hundred relations in the place.
 *   Mr. Bilbo never did a kinder deed than when he brought the lad back
 *   to live among decent folk.'                           --the Gaffer
 *
 *     [p.23 of _The Lord of the Rings_, I/i: "A Long-Expected Party"]
 */

/* XXX DAPM
 * As of Sept 2002, this file is new and may be in a state of flux for
 * a while. I've marked things I intent to come back and look at further
 * with an 'XXX DAPM' comment.
 */

/*
=head1 Pad Data Structures

This file contains the functions that create and manipulate scratchpads,
which are array-of-array data structures attached to a CV (ie a sub)
and which store lexical variables and opcode temporary and per-thread
values.

=for apidoc m|AV *|CvPADLIST|CV *cv
CV's can have CvPADLIST(cv) set to point to an AV.

For these purposes "forms" are a kind-of CV, eval""s are too (except they're
not callable at will and are always thrown away after the eval"" is done
executing). Require'd files are simply evals without any outer lexical
scope.

XSUBs don't have CvPADLIST set - dXSTARG fetches values from PL_curpad,
but that is really the callers pad (a slot of which is allocated by
every entersub).

The CvPADLIST AV has does not have AvREAL set, so REFCNT of component items
is managed "manual" (mostly in pad.c) rather than normal av.c rules.
The items in the AV are not SVs as for a normal AV, but other AVs:

0'th Entry of the CvPADLIST is an AV which represents the "names" or rather
the "static type information" for lexicals.

The CvDEPTH'th entry of CvPADLIST AV is an AV which is the stack frame at that
depth of recursion into the CV.
The 0'th slot of a frame AV is an AV which is @_.
other entries are storage for variables and op targets.

During compilation:
C<PL_comppad_name> is set to the names AV.
C<PL_comppad> is set to the frame AV for the frame CvDEPTH == 1.
C<PL_curpad> is set to the body of the frame AV (i.e. AvARRAY(PL_comppad)).

During execution, C<PL_comppad> and C<PL_curpad> refer to the live
frame of the currently executing sub.

Iterating over the names AV iterates over all possible pad
items. Pad slots that are SVs_PADTMP (targets/GVs/constants) end up having
&PL_sv_undef "names" (see pad_alloc()).

Only my/our variable (SVs_PADMY/SVs_PADOUR) slots get valid names.
The rest are op targets/GVs/constants which are statically allocated
or resolved at compile time.  These don't have names by which they
can be looked up from Perl code at run time through eval"" like
my/our variables can be.  Since they can't be looked up by "name"
but only by their index allocated at compile time (which is usually
in PL_op->op_targ), wasting a name SV for them doesn't make sense.

The SVs in the names AV have their PV being the name of the variable.
xlow+1..xhigh inclusive in the NV union is a range of cop_seq numbers for
which the name is valid.  For typed lexicals name SV is SVt_PVMG and SvSTASH
points at the type.  For C<our> lexicals, the type is also SVt_PVMG, with the
SvOURSTASH slot pointing at the stash of the associated global (so that
duplicate C<our> declarations in the same package can be detected).  SvUVX is
sometimes hijacked to store the generation number during compilation.

If SvFAKE is set on the name SV, then that slot in the frame AV is
a REFCNT'ed reference to a lexical from "outside". In this case,
the name SV does not use xlow and xhigh to store a cop_seq range, since it is
in scope throughout. Instead xhigh stores some flags containing info about
the real lexical (is it declared in an anon, and is it capable of being
instantiated multiple times?), and for fake ANONs, xlow contains the index
within the parent's pad where the lexical's value is stored, to make
cloning quicker.

If the 'name' is '&' the corresponding entry in frame AV
is a CV representing a possible closure.
(SvFAKE and name of '&' is not a meaningful combination currently but could
become so if C<my sub foo {}> is implemented.)

Note that formats are treated as anon subs, and are cloned each time
write is called (if necessary).

The flag SVs_PADSTALE is cleared on lexicals each time the my() is executed,
and set on scope exit. This allows the 'Variable $x is not available' warning
to be generated in evals, such as 

    { my $x = 1; sub f { eval '$x'} } f();

For state vars, SVs_PADSTALE is overloaded to mean 'not yet initialised'

=cut
*/


#include "EXTERN.h"
#define PERL_IN_PAD_C
#include "perl.h"
#include "keywords.h"

#define COP_SEQ_RANGE_LOW_set(sv,val)		\
  STMT_START { ((XPVNV*)SvANY(sv))->xnv_u.xpad_cop_seq.xlow = (val); } STMT_END
#define COP_SEQ_RANGE_HIGH_set(sv,val)		\
  STMT_START { ((XPVNV*)SvANY(sv))->xnv_u.xpad_cop_seq.xhigh = (val); } STMT_END

#define PARENT_PAD_INDEX_set(sv,val)		\
  STMT_START { ((XPVNV*)SvANY(sv))->xnv_u.xpad_cop_seq.xlow = (val); } STMT_END
#define PARENT_FAKELEX_FLAGS_set(sv,val)	\
  STMT_START { ((XPVNV*)SvANY(sv))->xnv_u.xpad_cop_seq.xhigh = (val); } STMT_END

#define PAD_MAX I32_MAX

#ifdef PERL_MAD
void pad_peg(const char* s) {
    static int pegcnt; /* XXX not threadsafe */
    PERL_UNUSED_ARG(s);

    PERL_ARGS_ASSERT_PAD_PEG;

    pegcnt++;
}
#endif

/*
=for apidoc pad_new

Create a new compiling padlist, saving and updating the various global
vars at the same time as creating the pad itself. The following flags
can be OR'ed together:

    padnew_CLONE	this pad is for a cloned CV
    padnew_SAVE		save old globals
    padnew_SAVESUB	also save extra stuff for start of sub

=cut
*/

PADLIST *
Perl_pad_new(pTHX_ int flags)
{
    dVAR;
    AV *padlist, *padname, *pad;
    SV **ary;

    ASSERT_CURPAD_LEGAL("pad_new");

    /* XXX DAPM really need a new SAVEt_PAD which restores all or most
     * vars (based on flags) rather than storing vals + addresses for
     * each individually. Also see pad_block_start.
     * XXX DAPM Try to see whether all these conditionals are required
     */

    /* save existing state, ... */

    if (flags & padnew_SAVE) {
	SAVECOMPPAD();
	SAVESPTR(PL_comppad_name);
	if (! (flags & padnew_CLONE)) {
	    SAVEI32(PL_padix);
	    SAVEI32(PL_comppad_name_fill);
	    SAVEI32(PL_min_intro_pending);
	    SAVEI32(PL_max_intro_pending);
	    SAVEBOOL(PL_cv_has_eval);
	    if (flags & padnew_SAVESUB) {
		SAVEBOOL(PL_pad_reset_pending);
	    }
	}
    }
    /* XXX DAPM interestingly, PL_comppad_name_floor never seems to be
     * saved - check at some pt that this is okay */

    /* ... create new pad ... */

    padlist	= newAV();
    padname	= newAV();
    pad		= newAV();

    if (flags & padnew_CLONE) {
	/* XXX DAPM  I dont know why cv_clone needs it
	 * doing differently yet - perhaps this separate branch can be
	 * dispensed with eventually ???
	 */

        AV * const a0 = newAV();			/* will be @_ */
	av_store(pad, 0, MUTABLE_SV(a0));
	AvREIFY_only(a0);
    }
    else {
	av_store(pad, 0, NULL);
    }

    AvREAL_off(padlist);
    /* Most subroutines never recurse, hence only need 2 entries in the padlist
       array - names, and depth=1.  The default for av_store() is to allocate
       0..3, and even an explicit call to av_extend() with <3 will be rounded
       up, so we inline the allocation of the array here.  */
    Newx(ary, 2, SV*);
    AvFILLp(padlist) = 1;
    AvMAX(padlist) = 1;
    AvALLOC(padlist) = ary;
    AvARRAY(padlist) = ary;
    ary[0] = MUTABLE_SV(padname);
    ary[1] = MUTABLE_SV(pad);

    /* ... then update state variables */

    PL_comppad_name	= padname;
    PL_comppad		= pad;
    PL_curpad		= AvARRAY(pad);

    if (! (flags & padnew_CLONE)) {
	PL_comppad_name_fill = 0;
	PL_min_intro_pending = 0;
	PL_padix	     = 0;
	PL_cv_has_eval	     = 0;
    }

    DEBUG_X(PerlIO_printf(Perl_debug_log,
	  "Pad 0x%"UVxf"[0x%"UVxf"] new:       compcv=0x%"UVxf
	      " name=0x%"UVxf" flags=0x%"UVxf"\n",
	  PTR2UV(PL_comppad), PTR2UV(PL_curpad), PTR2UV(PL_compcv),
	      PTR2UV(padname), (UV)flags
	)
    );

    return (PADLIST*)padlist;
}


/*
=head1 Embedding Functions

=for apidoc cv_undef

Clear out all the active components of a CV. This can happen either
by an explicit C<undef &foo>, or by the reference count going to zero.
In the former case, we keep the CvOUTSIDE pointer, so that any anonymous
children can still follow the full lexical scope chain.

=cut
*/

void
Perl_cv_undef(pTHX_ CV *cv)
{
    dVAR;
    const PADLIST *padlist = CvPADLIST(cv);

    PERL_ARGS_ASSERT_CV_UNDEF;

    DEBUG_X(PerlIO_printf(Perl_debug_log,
	  "CV undef: cv=0x%"UVxf" comppad=0x%"UVxf"\n",
	    PTR2UV(cv), PTR2UV(PL_comppad))
    );

#ifdef USE_ITHREADS
    if (CvFILE(cv) && !CvISXSUB(cv)) {
	/* for XSUBs CvFILE point directly to static memory; __FILE__ */
	Safefree(CvFILE(cv));
    }
    CvFILE(cv) = NULL;
#endif

    if (!CvISXSUB(cv) && CvROOT(cv)) {
	if (SvTYPE(cv) == SVt_PVCV && CvDEPTH(cv))
	    Perl_croak(aTHX_ "Can't undef active subroutine");
	ENTER;

	PAD_SAVE_SETNULLPAD();

	op_free(CvROOT(cv));
	CvROOT(cv) = NULL;
	CvSTART(cv) = NULL;
	LEAVE;
    }
    SvPOK_off(MUTABLE_SV(cv));		/* forget prototype */
    CvGV_set(cv, NULL);

    /* This statement and the subsequence if block was pad_undef().  */
    pad_peg("pad_undef");

    if (padlist && !SvIS_FREED(padlist) /* may be during global destruction */
	) {
	I32 ix;

	/* Free the padlist associated with a CV.
	   If parts of it happen to be current, we null the relevant PL_*pad*
	   global vars so that we don't have any dangling references left.
	   We also repoint the CvOUTSIDE of any about-to-be-orphaned inner
	   subs to the outer of this cv.  */

	DEBUG_X(PerlIO_printf(Perl_debug_log,
			      "Pad undef: cv=0x%"UVxf" padlist=0x%"UVxf" comppad=0x%"UVxf"\n",
			      PTR2UV(cv), PTR2UV(padlist), PTR2UV(PL_comppad))
		);

	/* detach any '&' anon children in the pad; if afterwards they
	 * are still live, fix up their CvOUTSIDEs to point to our outside,
	 * bypassing us. */
	/* XXX DAPM for efficiency, we should only do this if we know we have
	 * children, or integrate this loop with general cleanup */

	if (PL_phase != PERL_PHASE_DESTRUCT) { /* don't bother during global destruction */
	    CV * const outercv = CvOUTSIDE(cv);
	    const U32 seq = CvOUTSIDE_SEQ(cv);
	    AV *  const comppad_name = MUTABLE_AV(AvARRAY(padlist)[0]);
	    SV ** const namepad = AvARRAY(comppad_name);
	    AV *  const comppad = MUTABLE_AV(AvARRAY(padlist)[1]);
	    SV ** const curpad = AvARRAY(comppad);
	    for (ix = AvFILLp(comppad_name); ix > 0; ix--) {
		SV * const namesv = namepad[ix];
		if (namesv && namesv != &PL_sv_undef
		    && *SvPVX_const(namesv) == '&')
		    {
			CV * const innercv = MUTABLE_CV(curpad[ix]);
			U32 inner_rc = SvREFCNT(innercv);
			assert(inner_rc);
			namepad[ix] = NULL;
			SvREFCNT_dec(namesv);

			if (SvREFCNT(comppad) < 2) { /* allow for /(?{ sub{} })/  */
			    curpad[ix] = NULL;
			    SvREFCNT_dec(innercv);
			    inner_rc--;
			}

			/* in use, not just a prototype */
			if (inner_rc && (CvOUTSIDE(innercv) == cv)) {
			    assert(CvWEAKOUTSIDE(innercv));
			    /* don't relink to grandfather if he's being freed */
			    if (outercv && SvREFCNT(outercv)) {
				CvWEAKOUTSIDE_off(innercv);
				CvOUTSIDE(innercv) = outercv;
				CvOUTSIDE_SEQ(innercv) = seq;
				SvREFCNT_inc_simple_void_NN(outercv);
			    }
			    else {
				CvOUTSIDE(innercv) = NULL;
			    }
			}
		    }
	    }
	}

	ix = AvFILLp(padlist);
	while (ix >= 0) {
	    SV* const sv = AvARRAY(padlist)[ix--];
	    if (sv) {
		if (sv == (const SV *)PL_comppad_name)
		    PL_comppad_name = NULL;
		else if (sv == (const SV *)PL_comppad) {
		    PL_comppad = NULL;
		    PL_curpad = NULL;
		}
	    }
	    SvREFCNT_dec(sv);
	}
	SvREFCNT_dec(MUTABLE_SV(CvPADLIST(cv)));
	CvPADLIST(cv) = NULL;
    }


    /* remove CvOUTSIDE unless this is an undef rather than a free */
    if (!SvREFCNT(cv) && CvOUTSIDE(cv)) {
	if (!CvWEAKOUTSIDE(cv))
	    SvREFCNT_dec(CvOUTSIDE(cv));
	CvOUTSIDE(cv) = NULL;
    }
    if (CvCONST(cv)) {
	SvREFCNT_dec(MUTABLE_SV(CvXSUBANY(cv).any_ptr));
	CvCONST_off(cv);
    }
    if (CvISXSUB(cv) && CvXSUB(cv)) {
	CvXSUB(cv) = NULL;
    }
    /* delete all flags except WEAKOUTSIDE and CVGV_RC, which indicate the
     * ref status of CvOUTSIDE and CvGV */
    CvFLAGS(cv) &= (CVf_WEAKOUTSIDE|CVf_CVGV_RC);
}

static PADOFFSET
S_pad_add_name_sv(pTHX_ SV *namesv, const U32 flags, HV *typestash,
		  HV *ourstash)
{
    dVAR;
    const PADOFFSET offset = pad_alloc(OP_PADSV, SVs_PADMY);

    PERL_ARGS_ASSERT_PAD_ADD_NAME_SV;

    ASSERT_CURPAD_ACTIVE("pad_add_name");

    if (typestash) {
	assert(SvTYPE(namesv) == SVt_PVMG);
	SvPAD_TYPED_on(namesv);
	SvSTASH_set(namesv, MUTABLE_HV(SvREFCNT_inc_simple_NN(MUTABLE_SV(typestash))));
    }
    if (ourstash) {
	SvPAD_OUR_on(namesv);
	SvOURSTASH_set(namesv, ourstash);
	SvREFCNT_inc_simple_void_NN(ourstash);
    }
    else if (flags & padadd_STATE) {
	SvPAD_STATE_on(namesv);
    }

    av_store(PL_comppad_name, offset, namesv);
    return offset;
}

/*
=for apidoc pad_add_name

Create a new name and associated PADMY SV in the current pad; return the
offset.
If C<typestash> is valid, the name is for a typed lexical; set the
name's stash to that value.
If C<ourstash> is valid, it's an our lexical, set the name's
SvOURSTASH to that value

If fake, it means we're cloning an existing entry

=cut
*/

PADOFFSET
Perl_pad_add_name(pTHX_ const char *name, const STRLEN len, const U32 flags,
		  HV *typestash, HV *ourstash)
{
    dVAR;
    PADOFFSET offset;
    SV *namesv;

    PERL_ARGS_ASSERT_PAD_ADD_NAME;

    if (flags & ~(padadd_OUR|padadd_STATE|padadd_NO_DUP_CHECK))
	Perl_croak(aTHX_ "panic: pad_add_name illegal flag bits 0x%" UVxf,
		   (UV)flags);

    namesv = newSV_type((ourstash || typestash) ? SVt_PVMG : SVt_PVNV);

    /* Until we're using the length for real, cross check that we're being told
       the truth.  */
    PERL_UNUSED_ARG(len);
    assert(strlen(name) == len);

    sv_setpv(namesv, name);

    if ((flags & padadd_NO_DUP_CHECK) == 0) {
	/* check for duplicate declaration */
	pad_check_dup(namesv, flags & padadd_OUR, ourstash);
    }

    offset = pad_add_name_sv(namesv, flags, typestash, ourstash);

    /* not yet introduced */
    COP_SEQ_RANGE_LOW_set(namesv, PAD_MAX);	/* min */
    COP_SEQ_RANGE_HIGH_set(namesv, 0);		/* max */

    if (!PL_min_intro_pending)
	PL_min_intro_pending = offset;
    PL_max_intro_pending = offset;
    /* if it's not a simple scalar, replace with an AV or HV */
    assert(SvTYPE(PL_curpad[offset]) == SVt_NULL);
    assert(SvREFCNT(PL_curpad[offset]) == 1);
    if (*name == '@')
	sv_upgrade(PL_curpad[offset], SVt_PVAV);
    else if (*name == '%')
	sv_upgrade(PL_curpad[offset], SVt_PVHV);
    assert(SvPADMY(PL_curpad[offset]));
    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
			   "Pad addname: %ld \"%s\" new lex=0x%"UVxf"\n",
			   (long)offset, name, PTR2UV(PL_curpad[offset])));

    return offset;
}




/*
=for apidoc pad_alloc

Allocate a new my or tmp pad entry. For a my, simply push a null SV onto
the end of PL_comppad, but for a tmp, scan the pad from PL_padix upwards
for a slot which has no name and no active value.

=cut
*/

/* XXX DAPM integrate alloc(), add_name() and add_anon(),
 * or at least rationalise ??? */
/* And flag whether the incoming name is UTF8 or 8 bit?
   Could do this either with the +ve/-ve hack of the HV code, or expanding
   the flag bits. Either way, this makes proper Unicode safe pad support.
   NWC
*/

PADOFFSET
Perl_pad_alloc(pTHX_ I32 optype, U32 tmptype)
{
    dVAR;
    SV *sv;
    I32 retval;

    PERL_UNUSED_ARG(optype);
    ASSERT_CURPAD_ACTIVE("pad_alloc");

    if (AvARRAY(PL_comppad) != PL_curpad)
	Perl_croak(aTHX_ "panic: pad_alloc");
    if (PL_pad_reset_pending)
	pad_reset();
    if (tmptype & SVs_PADMY) {
	sv = *av_fetch(PL_comppad, AvFILLp(PL_comppad) + 1, TRUE);
	retval = AvFILLp(PL_comppad);
    }
    else {
	SV * const * const names = AvARRAY(PL_comppad_name);
        const SSize_t names_fill = AvFILLp(PL_comppad_name);
	for (;;) {
	    /*
	     * "foreach" index vars temporarily become aliases to non-"my"
	     * values.  Thus we must skip, not just pad values that are
	     * marked as current pad values, but also those with names.
	     */
	    /* HVDS why copy to sv here? we don't seem to use it */
	    if (++PL_padix <= names_fill &&
		   (sv = names[PL_padix]) && sv != &PL_sv_undef)
		continue;
	    sv = *av_fetch(PL_comppad, PL_padix, TRUE);
	    if (!(SvFLAGS(sv) & (SVs_PADTMP | SVs_PADMY)) &&
		!IS_PADGV(sv) && !IS_PADCONST(sv))
		break;
	}
	retval = PL_padix;
    }
    SvFLAGS(sv) |= tmptype;
    PL_curpad = AvARRAY(PL_comppad);

    DEBUG_X(PerlIO_printf(Perl_debug_log,
	  "Pad 0x%"UVxf"[0x%"UVxf"] alloc:   %ld for %s\n",
	  PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long) retval,
	  PL_op_name[optype]));
#ifdef DEBUG_LEAKING_SCALARS
    sv->sv_debug_optype = optype;
    sv->sv_debug_inpad = 1;
#endif
    return (PADOFFSET)retval;
}

/*
=for apidoc pad_add_anon

Add an anon code entry to the current compiling pad

=cut
*/

PADOFFSET
Perl_pad_add_anon(pTHX_ SV* sv, OPCODE op_type)
{
    dVAR;
    PADOFFSET ix;
    SV* const name = newSV_type(SVt_PVNV);

    PERL_ARGS_ASSERT_PAD_ADD_ANON;

    pad_peg("add_anon");
    sv_setpvs(name, "&");
    /* Are these two actually ever read? */
    COP_SEQ_RANGE_HIGH_set(name, ~0);
    COP_SEQ_RANGE_LOW_set(name, 1);
    ix = pad_alloc(op_type, SVs_PADMY);
    av_store(PL_comppad_name, ix, name);
    /* XXX DAPM use PL_curpad[] ? */
    av_store(PL_comppad, ix, sv);
    SvPADMY_on(sv);

    /* to avoid ref loops, we never have parent + child referencing each
     * other simultaneously */
    if (CvOUTSIDE((const CV *)sv)) {
	assert(!CvWEAKOUTSIDE((const CV *)sv));
	CvWEAKOUTSIDE_on(MUTABLE_CV(sv));
	SvREFCNT_dec(CvOUTSIDE(MUTABLE_CV(sv)));
    }
    return ix;
}



/*
=for apidoc pad_check_dup

Check for duplicate declarations: report any of:
     * a my in the current scope with the same name;
     * an our (anywhere in the pad) with the same name and the same stash
       as C<ourstash>
C<is_our> indicates that the name to check is an 'our' declaration

=cut
*/

STATIC void
S_pad_check_dup(pTHX_ SV *name, const U32 flags, const HV *ourstash)
{
    dVAR;
    SV		**svp;
    PADOFFSET	top, off;
    const U32	is_our = flags & padadd_OUR;

    PERL_ARGS_ASSERT_PAD_CHECK_DUP;

    ASSERT_CURPAD_ACTIVE("pad_check_dup");

    assert((flags & ~padadd_OUR) == 0);

    if (AvFILLp(PL_comppad_name) < 0 || !ckWARN(WARN_MISC))
	return; /* nothing to check */

    svp = AvARRAY(PL_comppad_name);
    top = AvFILLp(PL_comppad_name);
    /* check the current scope */
    /* XXX DAPM - why the (I32) cast - shouldn't we ensure they're the same
     * type ? */
    for (off = top; (I32)off > PL_comppad_name_floor; off--) {
	SV * const sv = svp[off];
	if (sv
	    && sv != &PL_sv_undef
	    && !SvFAKE(sv)
	    && (COP_SEQ_RANGE_HIGH(sv) == PAD_MAX || COP_SEQ_RANGE_HIGH(sv) == 0)
	    && sv_eq(name, sv))
	{
	    if (is_our && (SvPAD_OUR(sv)))
		break; /* "our" masking "our" */
	    Perl_warner(aTHX_ packWARN(WARN_MISC),
		"\"%s\" variable %"SVf" masks earlier declaration in same %s",
		(is_our ? "our" : PL_parser->in_my == KEY_my ? "my" : "state"),
		sv,
		(COP_SEQ_RANGE_HIGH(sv) == PAD_MAX ? "scope" : "statement"));
	    --off;
	    break;
	}
    }
    /* check the rest of the pad */
    if (is_our) {
	while (off > 0) {
	    SV * const sv = svp[off];
	    if (sv
		&& sv != &PL_sv_undef
		&& !SvFAKE(sv)
		&& (COP_SEQ_RANGE_HIGH(sv) == PAD_MAX || COP_SEQ_RANGE_HIGH(sv) == 0)
		&& SvOURSTASH(sv) == ourstash
		&& sv_eq(name, sv))
	    {
		Perl_warner(aTHX_ packWARN(WARN_MISC),
		    "\"our\" variable %"SVf" redeclared", sv);
		if ((I32)off <= PL_comppad_name_floor)
		    Perl_warner(aTHX_ packWARN(WARN_MISC),
			"\t(Did you mean \"local\" instead of \"our\"?)\n");
		break;
	    }
	    --off;
	}
    }
}


/*
=for apidoc pad_findmy

Given a lexical name, try to find its offset, first in the current pad,
or failing that, in the pads of any lexically enclosing subs (including
the complications introduced by eval). If the name is found in an outer pad,
then a fake entry is added to the current pad.
Returns the offset in the current pad, or NOT_IN_PAD on failure.

=cut
*/

PADOFFSET
Perl_pad_findmy(pTHX_ const char *name, STRLEN len, U32 flags)
{
    dVAR;
    SV *out_sv;
    int out_flags;
    I32 offset;
    const AV *nameav;
    SV **name_svp;

    PERL_ARGS_ASSERT_PAD_FINDMY;

    pad_peg("pad_findmy");

    if (flags)
	Perl_croak(aTHX_ "panic: pad_findmy illegal flag bits 0x%" UVxf,
		   (UV)flags);

    /* Yes, it is a bug (read work in progress) that we're not really using this
       length parameter, and instead relying on strlen() later on. But I'm not
       comfortable about changing the pad API piecemeal to use and rely on
       lengths. This only exists to avoid an "unused parameter" warning.  */
    if (len < 2) 
	return NOT_IN_PAD;

    /* But until we're using the length for real, cross check that we're being
       told the truth.  */
    assert(strlen(name) == len);

    offset = pad_findlex(name, PL_compcv, PL_cop_seqmax, 1,
		NULL, &out_sv, &out_flags);
    if ((PADOFFSET)offset != NOT_IN_PAD) 
	return offset;

    /* look for an our that's being introduced; this allows
     *    our $foo = 0 unless defined $foo;
     * to not give a warning. (Yes, this is a hack) */

    nameav = MUTABLE_AV(AvARRAY(CvPADLIST(PL_compcv))[0]);
    name_svp = AvARRAY(nameav);
    for (offset = AvFILLp(nameav); offset > 0; offset--) {
        const SV * const namesv = name_svp[offset];
	if (namesv && namesv != &PL_sv_undef
	    && !SvFAKE(namesv)
	    && (SvPAD_OUR(namesv))
	    && strEQ(SvPVX_const(namesv), name)
	    && COP_SEQ_RANGE_LOW(namesv) == PAD_MAX /* min */
	)
	    return offset;
    }
    return NOT_IN_PAD;
}

/*
 * Returns the offset of a lexical $_, if there is one, at run time.
 * Used by the UNDERBAR XS macro.
 */

PADOFFSET
Perl_find_rundefsvoffset(pTHX)
{
    dVAR;
    SV *out_sv;
    int out_flags;
    return pad_findlex("$_", find_runcv(NULL), PL_curcop->cop_seq, 1,
	    NULL, &out_sv, &out_flags);
}

/*
 * Returns a lexical $_, if there is one, at run time ; or the global one
 * otherwise.
 */

SV *
Perl_find_rundefsv(pTHX)
{
    SV *namesv;
    int flags;
    PADOFFSET po;

    po = pad_findlex("$_", find_runcv(NULL), PL_curcop->cop_seq, 1,
	    NULL, &namesv, &flags);

    if (po == NOT_IN_PAD
	|| (SvFLAGS(namesv) & (SVpad_NAME|SVpad_OUR)) == (SVpad_NAME|SVpad_OUR))
	return DEFSV;

    return PAD_SVl(po);
}

/*
=for apidoc pad_findlex

Find a named lexical anywhere in a chain of nested pads. Add fake entries
in the inner pads if it's found in an outer one.

Returns the offset in the bottom pad of the lex or the fake lex.
cv is the CV in which to start the search, and seq is the current cop_seq
to match against. If warn is true, print appropriate warnings.  The out_*
vars return values, and so are pointers to where the returned values
should be stored. out_capture, if non-null, requests that the innermost
instance of the lexical is captured; out_name_sv is set to the innermost
matched namesv or fake namesv; out_flags returns the flags normally
associated with the IVX field of a fake namesv.

Note that pad_findlex() is recursive; it recurses up the chain of CVs,
then comes back down, adding fake entries as it goes. It has to be this way
because fake namesvs in anon protoypes have to store in xlow the index into
the parent pad.

=cut
*/

/* the CV has finished being compiled. This is not a sufficient test for
 * all CVs (eg XSUBs), but suffices for the CVs found in a lexical chain */
#define CvCOMPILED(cv)	CvROOT(cv)

/* the CV does late binding of its lexicals */
#define CvLATE(cv) (CvANON(cv) || SvTYPE(cv) == SVt_PVFM)


STATIC PADOFFSET
S_pad_findlex(pTHX_ const char *name, const CV* cv, U32 seq, int warn,
	SV** out_capture, SV** out_name_sv, int *out_flags)
{
    dVAR;
    I32 offset, new_offset;
    SV *new_capture;
    SV **new_capturep;
    const AV * const padlist = CvPADLIST(cv);

    PERL_ARGS_ASSERT_PAD_FINDLEX;

    *out_flags = 0;

    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
	"Pad findlex cv=0x%"UVxf" searching \"%s\" seq=%d%s\n",
	PTR2UV(cv), name, (int)seq, out_capture ? " capturing" : "" ));

    /* first, search this pad */

    if (padlist) { /* not an undef CV */
	I32 fake_offset = 0;
        const AV * const nameav = MUTABLE_AV(AvARRAY(padlist)[0]);
	SV * const * const name_svp = AvARRAY(nameav);

	for (offset = AvFILLp(nameav); offset > 0; offset--) {
            const SV * const namesv = name_svp[offset];
	    if (namesv && namesv != &PL_sv_undef
		    && strEQ(SvPVX_const(namesv), name))
	    {
		if (SvFAKE(namesv))
		    fake_offset = offset; /* in case we don't find a real one */
		else if (  seq >  COP_SEQ_RANGE_LOW(namesv)	/* min */
			&& seq <= COP_SEQ_RANGE_HIGH(namesv))	/* max */
		    break;
	    }
	}

	if (offset > 0 || fake_offset > 0 ) { /* a match! */
	    if (offset > 0) { /* not fake */
		fake_offset = 0;
		*out_name_sv = name_svp[offset]; /* return the namesv */

		/* set PAD_FAKELEX_MULTI if this lex can have multiple
		 * instances. For now, we just test !CvUNIQUE(cv), but
		 * ideally, we should detect my's declared within loops
		 * etc - this would allow a wider range of 'not stayed
		 * shared' warnings. We also treated alreadly-compiled
		 * lexes as not multi as viewed from evals. */

		*out_flags = CvANON(cv) ?
			PAD_FAKELEX_ANON :
			    (!CvUNIQUE(cv) && ! CvCOMPILED(cv))
				? PAD_FAKELEX_MULTI : 0;

		DEBUG_Xv(PerlIO_printf(Perl_debug_log,
		    "Pad findlex cv=0x%"UVxf" matched: offset=%ld (%lu,%lu)\n",
		    PTR2UV(cv), (long)offset,
		    (unsigned long)COP_SEQ_RANGE_LOW(*out_name_sv),
		    (unsigned long)COP_SEQ_RANGE_HIGH(*out_name_sv)));
	    }
	    else { /* fake match */
		offset = fake_offset;
		*out_name_sv = name_svp[offset]; /* return the namesv */
		*out_flags = PARENT_FAKELEX_FLAGS(*out_name_sv);
		DEBUG_Xv(PerlIO_printf(Perl_debug_log,
		    "Pad findlex cv=0x%"UVxf" matched: offset=%ld flags=0x%lx index=%lu\n",
		    PTR2UV(cv), (long)offset, (unsigned long)*out_flags,
		    (unsigned long) PARENT_PAD_INDEX(*out_name_sv) 
		));
	    }

	    /* return the lex? */

	    if (out_capture) {

		/* our ? */
		if (SvPAD_OUR(*out_name_sv)) {
		    *out_capture = NULL;
		    return offset;
		}

		/* trying to capture from an anon prototype? */
		if (CvCOMPILED(cv)
			? CvANON(cv) && CvCLONE(cv) && !CvCLONED(cv)
			: *out_flags & PAD_FAKELEX_ANON)
		{
		    if (warn)
			Perl_ck_warner(aTHX_ packWARN(WARN_CLOSURE),
				       "Variable \"%s\" is not available", name);
		    *out_capture = NULL;
		}

		/* real value */
		else {
		    int newwarn = warn;
		    if (!CvCOMPILED(cv) && (*out_flags & PAD_FAKELEX_MULTI)
			 && !SvPAD_STATE(name_svp[offset])
			 && warn && ckWARN(WARN_CLOSURE)) {
			newwarn = 0;
			Perl_warner(aTHX_ packWARN(WARN_CLOSURE),
			    "Variable \"%s\" will not stay shared", name);
		    }

		    if (fake_offset && CvANON(cv)
			    && CvCLONE(cv) &&!CvCLONED(cv))
		    {
			SV *n;
			/* not yet caught - look further up */
			DEBUG_Xv(PerlIO_printf(Perl_debug_log,
			    "Pad findlex cv=0x%"UVxf" chasing lex in outer pad\n",
			    PTR2UV(cv)));
			n = *out_name_sv;
			(void) pad_findlex(name, CvOUTSIDE(cv),
			    CvOUTSIDE_SEQ(cv),
			    newwarn, out_capture, out_name_sv, out_flags);
			*out_name_sv = n;
			return offset;
		    }

		    *out_capture = AvARRAY(MUTABLE_AV(AvARRAY(padlist)[
				    CvDEPTH(cv) ? CvDEPTH(cv) : 1]))[offset];
		    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
			"Pad findlex cv=0x%"UVxf" found lex=0x%"UVxf"\n",
			PTR2UV(cv), PTR2UV(*out_capture)));

		    if (SvPADSTALE(*out_capture)
			&& !SvPAD_STATE(name_svp[offset]))
		    {
			Perl_ck_warner(aTHX_ packWARN(WARN_CLOSURE),
				       "Variable \"%s\" is not available", name);
			*out_capture = NULL;
		    }
		}
		if (!*out_capture) {
		    if (*name == '@')
			*out_capture = sv_2mortal(MUTABLE_SV(newAV()));
		    else if (*name == '%')
			*out_capture = sv_2mortal(MUTABLE_SV(newHV()));
		    else
			*out_capture = sv_newmortal();
		}
	    }

	    return offset;
	}
    }

    /* it's not in this pad - try above */

    if (!CvOUTSIDE(cv))
	return NOT_IN_PAD;

    /* out_capture non-null means caller wants us to capture lex; in
     * addition we capture ourselves unless it's an ANON/format */
    new_capturep = out_capture ? out_capture :
		CvLATE(cv) ? NULL : &new_capture;

    offset = pad_findlex(name, CvOUTSIDE(cv), CvOUTSIDE_SEQ(cv), 1,
		new_capturep, out_name_sv, out_flags);
    if ((PADOFFSET)offset == NOT_IN_PAD)
	return NOT_IN_PAD;

    /* found in an outer CV. Add appropriate fake entry to this pad */

    /* don't add new fake entries (via eval) to CVs that we have already
     * finished compiling, or to undef CVs */
    if (CvCOMPILED(cv) || !padlist)
	return 0; /* this dummy (and invalid) value isnt used by the caller */

    {
	/* This relies on sv_setsv_flags() upgrading the destination to the same
	   type as the source, independant of the flags set, and on it being
	   "good" and only copying flag bits and pointers that it understands.
	*/
	SV *new_namesv = newSVsv(*out_name_sv);
	AV *  const ocomppad_name = PL_comppad_name;
	PAD * const ocomppad = PL_comppad;
	PL_comppad_name = MUTABLE_AV(AvARRAY(padlist)[0]);
	PL_comppad = MUTABLE_AV(AvARRAY(padlist)[1]);
	PL_curpad = AvARRAY(PL_comppad);

	new_offset
	    = pad_add_name_sv(new_namesv,
			      (SvPAD_STATE(*out_name_sv) ? padadd_STATE : 0),
			      SvPAD_TYPED(*out_name_sv)
			      ? SvSTASH(*out_name_sv) : NULL,
			      SvOURSTASH(*out_name_sv)
			      );

	SvFAKE_on(new_namesv);
	DEBUG_Xv(PerlIO_printf(Perl_debug_log,
			       "Pad addname: %ld \"%.*s\" FAKE\n",
			       (long)new_offset,
			       (int) SvCUR(new_namesv), SvPVX(new_namesv)));
	PARENT_FAKELEX_FLAGS_set(new_namesv, *out_flags);

	PARENT_PAD_INDEX_set(new_namesv, 0);
	if (SvPAD_OUR(new_namesv)) {
	    NOOP;   /* do nothing */
	}
	else if (CvLATE(cv)) {
	    /* delayed creation - just note the offset within parent pad */
	    PARENT_PAD_INDEX_set(new_namesv, offset);
	    CvCLONE_on(cv);
	}
	else {
	    /* immediate creation - capture outer value right now */
	    av_store(PL_comppad, new_offset, SvREFCNT_inc(*new_capturep));
	    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
		"Pad findlex cv=0x%"UVxf" saved captured sv 0x%"UVxf" at offset %ld\n",
		PTR2UV(cv), PTR2UV(*new_capturep), (long)new_offset));
	}
	*out_name_sv = new_namesv;
	*out_flags = PARENT_FAKELEX_FLAGS(new_namesv);

	PL_comppad_name = ocomppad_name;
	PL_comppad = ocomppad;
	PL_curpad = ocomppad ? AvARRAY(ocomppad) : NULL;
    }
    return new_offset;
}


#ifdef DEBUGGING
/*
=for apidoc pad_sv

Get the value at offset po in the current pad.
Use macro PAD_SV instead of calling this function directly.

=cut
*/


SV *
Perl_pad_sv(pTHX_ PADOFFSET po)
{
    dVAR;
    ASSERT_CURPAD_ACTIVE("pad_sv");

    if (!po)
	Perl_croak(aTHX_ "panic: pad_sv po");
    DEBUG_X(PerlIO_printf(Perl_debug_log,
	"Pad 0x%"UVxf"[0x%"UVxf"] sv:      %ld sv=0x%"UVxf"\n",
	PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po, PTR2UV(PL_curpad[po]))
    );
    return PL_curpad[po];
}


/*
=for apidoc pad_setsv

Set the entry at offset po in the current pad to sv.
Use the macro PAD_SETSV() rather than calling this function directly.

=cut
*/

void
Perl_pad_setsv(pTHX_ PADOFFSET po, SV* sv)
{
    dVAR;

    PERL_ARGS_ASSERT_PAD_SETSV;

    ASSERT_CURPAD_ACTIVE("pad_setsv");

    DEBUG_X(PerlIO_printf(Perl_debug_log,
	"Pad 0x%"UVxf"[0x%"UVxf"] setsv:   %ld sv=0x%"UVxf"\n",
	PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po, PTR2UV(sv))
    );
    PL_curpad[po] = sv;
}
#endif



/*
=for apidoc pad_block_start

Update the pad compilation state variables on entry to a new block

=cut
*/

/* XXX DAPM perhaps:
 * 	- integrate this in general state-saving routine ???
 * 	- combine with the state-saving going on in pad_new ???
 * 	- introduce a new SAVE type that does all this in one go ?
 */

void
Perl_pad_block_start(pTHX_ int full)
{
    dVAR;
    ASSERT_CURPAD_ACTIVE("pad_block_start");
    SAVEI32(PL_comppad_name_floor);
    PL_comppad_name_floor = AvFILLp(PL_comppad_name);
    if (full)
	PL_comppad_name_fill = PL_comppad_name_floor;
    if (PL_comppad_name_floor < 0)
	PL_comppad_name_floor = 0;
    SAVEI32(PL_min_intro_pending);
    SAVEI32(PL_max_intro_pending);
    PL_min_intro_pending = 0;
    SAVEI32(PL_comppad_name_fill);
    SAVEI32(PL_padix_floor);
    PL_padix_floor = PL_padix;
    PL_pad_reset_pending = FALSE;
}


/*
=for apidoc intro_my

"Introduce" my variables to visible status.

=cut
*/

U32
Perl_intro_my(pTHX)
{
    dVAR;
    SV **svp;
    I32 i;

    ASSERT_CURPAD_ACTIVE("intro_my");
    if (! PL_min_intro_pending)
	return PL_cop_seqmax;

    svp = AvARRAY(PL_comppad_name);
    for (i = PL_min_intro_pending; i <= PL_max_intro_pending; i++) {
	SV * const sv = svp[i];

	if (sv && sv != &PL_sv_undef && !SvFAKE(sv) && !COP_SEQ_RANGE_HIGH(sv)) {
	    COP_SEQ_RANGE_HIGH_set(sv, PAD_MAX);	/* Don't know scope end yet. */
	    COP_SEQ_RANGE_LOW_set(sv, PL_cop_seqmax);
	    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
		"Pad intromy: %ld \"%s\", (%lu,%lu)\n",
		(long)i, SvPVX_const(sv),
		(unsigned long)COP_SEQ_RANGE_LOW(sv),
		(unsigned long)COP_SEQ_RANGE_HIGH(sv))
	    );
	}
    }
    PL_min_intro_pending = 0;
    PL_comppad_name_fill = PL_max_intro_pending; /* Needn't search higher */
    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
		"Pad intromy: seq -> %ld\n", (long)(PL_cop_seqmax+1)));

    return PL_cop_seqmax++;
}

/*
=for apidoc pad_leavemy

Cleanup at end of scope during compilation: set the max seq number for
lexicals in this scope and warn of any lexicals that never got introduced.

=cut
*/

void
Perl_pad_leavemy(pTHX)
{
    dVAR;
    I32 off;
    SV * const * const svp = AvARRAY(PL_comppad_name);

    PL_pad_reset_pending = FALSE;

    ASSERT_CURPAD_ACTIVE("pad_leavemy");
    if (PL_min_intro_pending && PL_comppad_name_fill < PL_min_intro_pending) {
	for (off = PL_max_intro_pending; off >= PL_min_intro_pending; off--) {
	    const SV * const sv = svp[off];
	    if (sv && sv != &PL_sv_undef && !SvFAKE(sv))
		Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
				 "%"SVf" never introduced",
				 SVfARG(sv));
	}
    }
    /* "Deintroduce" my variables that are leaving with this scope. */
    for (off = AvFILLp(PL_comppad_name); off > PL_comppad_name_fill; off--) {
	const SV * const sv = svp[off];
	if (sv && sv != &PL_sv_undef && !SvFAKE(sv) && COP_SEQ_RANGE_HIGH(sv) == PAD_MAX) {
	    COP_SEQ_RANGE_HIGH_set(sv, PL_cop_seqmax);
	    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
		"Pad leavemy: %ld \"%s\", (%lu,%lu)\n",
		(long)off, SvPVX_const(sv),
		(unsigned long)COP_SEQ_RANGE_LOW(sv),
		(unsigned long)COP_SEQ_RANGE_HIGH(sv))
	    );
	}
    }
    PL_cop_seqmax++;
    DEBUG_Xv(PerlIO_printf(Perl_debug_log,
	    "Pad leavemy: seq = %ld\n", (long)PL_cop_seqmax));
}


/*
=for apidoc pad_swipe

Abandon the tmp in the current pad at offset po and replace with a
new one.

=cut
*/

void
Perl_pad_swipe(pTHX_ PADOFFSET po, bool refadjust)
{
    dVAR;
    ASSERT_CURPAD_LEGAL("pad_swipe");
    if (!PL_curpad)
	return;
    if (AvARRAY(PL_comppad) != PL_curpad)
	Perl_croak(aTHX_ "panic: pad_swipe curpad");
    if (!po)
	Perl_croak(aTHX_ "panic: pad_swipe po");

    DEBUG_X(PerlIO_printf(Perl_debug_log,
		"Pad 0x%"UVxf"[0x%"UVxf"] swipe:   %ld\n",
		PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po));

    if (PL_curpad[po])
	SvPADTMP_off(PL_curpad[po]);
    if (refadjust)
	SvREFCNT_dec(PL_curpad[po]);


    /* if pad tmps aren't shared between ops, then there's no need to
     * create a new tmp when an existing op is freed */
#ifdef USE_BROKEN_PAD_RESET
    PL_curpad[po] = newSV(0);
    SvPADTMP_on(PL_curpad[po]);
#else
    PL_curpad[po] = &PL_sv_undef;
#endif
    if ((I32)po < PL_padix)
	PL_padix = po - 1;
}


/*
=for apidoc pad_reset

Mark all the current temporaries for reuse

=cut
*/

/* XXX pad_reset() is currently disabled because it results in serious bugs.
 * It causes pad temp TARGs to be shared between OPs. Since TARGs are pushed
 * on the stack by OPs that use them, there are several ways to get an alias
 * to  a shared TARG.  Such an alias will change randomly and unpredictably.
 * We avoid doing this until we can think of a Better Way.
 * GSAR 97-10-29 */
static void
S_pad_reset(pTHX)
{
    dVAR;
#ifdef USE_BROKEN_PAD_RESET
    if (AvARRAY(PL_comppad) != PL_curpad)
	Perl_croak(aTHX_ "panic: pad_reset curpad");

    DEBUG_X(PerlIO_printf(Perl_debug_log,
	    "Pad 0x%"UVxf"[0x%"UVxf"] reset:     padix %ld -> %ld",
	    PTR2UV(PL_comppad), PTR2UV(PL_curpad),
		(long)PL_padix, (long)PL_padix_floor
	    )
    );

    if (!PL_tainting) {	/* Can't mix tainted and non-tainted temporaries. */
        register I32 po;
	for (po = AvMAX(PL_comppad); po > PL_padix_floor; po--) {
	    if (PL_curpad[po] && !SvIMMORTAL(PL_curpad[po]))
		SvPADTMP_off(PL_curpad[po]);
	}
	PL_padix = PL_padix_floor;
    }
#endif
    PL_pad_reset_pending = FALSE;
}


/*
=for apidoc pad_tidy

Tidy up a pad after we've finished compiling it:
    * remove most stuff from the pads of anonsub prototypes;
    * give it a @_;
    * mark tmps as such.

=cut
*/

/* XXX DAPM surely most of this stuff should be done properly
 * at the right time beforehand, rather than going around afterwards
 * cleaning up our mistakes ???
 */

void
Perl_pad_tidy(pTHX_ padtidy_type type)
{
    dVAR;

    ASSERT_CURPAD_ACTIVE("pad_tidy");

    /* If this CV has had any 'eval-capable' ops planted in it
     * (ie it contains eval '...', //ee, /$var/ or /(?{..})/), Then any
     * anon prototypes in the chain of CVs should be marked as cloneable,
     * so that for example the eval's CV in C<< sub { eval '$x' } >> gets
     * the right CvOUTSIDE.
     * If running with -d, *any* sub may potentially have an eval
     * excuted within it.
     */

    if (PL_cv_has_eval || PL_perldb) {
        const CV *cv;
	for (cv = PL_compcv ;cv; cv = CvOUTSIDE(cv)) {
	    if (cv != PL_compcv && CvCOMPILED(cv))
		break; /* no need to mark already-compiled code */
	    if (CvANON(cv)) {
		DEBUG_Xv(PerlIO_printf(Perl_debug_log,
		    "Pad clone on cv=0x%"UVxf"\n", PTR2UV(cv)));
		CvCLONE_on(cv);
	    }
	}
    }

    /* extend curpad to match namepad */
    if (AvFILLp(PL_comppad_name) < AvFILLp(PL_comppad))
	av_store(PL_comppad_name, AvFILLp(PL_comppad), NULL);

    if (type == padtidy_SUBCLONE) {
	SV * const * const namep = AvARRAY(PL_comppad_name);
	PADOFFSET ix;

	for (ix = AvFILLp(PL_comppad); ix > 0; ix--) {
	    SV *namesv;

	    if (SvIMMORTAL(PL_curpad[ix]) || IS_PADGV(PL_curpad[ix]) || IS_PADCONST(PL_curpad[ix]))
		continue;
	    /*
	     * The only things that a clonable function needs in its
	     * pad are anonymous subs.
	     * The rest are created anew during cloning.
	     */
	    if (!((namesv = namep[ix]) != NULL &&
		  namesv != &PL_sv_undef &&
		   *SvPVX_const(namesv) == '&'))
	    {
		SvREFCNT_dec(PL_curpad[ix]);
		PL_curpad[ix] = NULL;
	    }
	}
    }
    else if (type == padtidy_SUB) {
	/* XXX DAPM this same bit of code keeps appearing !!! Rationalise? */
	AV * const av = newAV();			/* Will be @_ */
	av_store(PL_comppad, 0, MUTABLE_SV(av));
	AvREIFY_only(av);
    }

    if (type == padtidy_SUB || type == padtidy_FORMAT) {
	SV * const * const namep = AvARRAY(PL_comppad_name);
	PADOFFSET ix;
	for (ix = AvFILLp(PL_comppad); ix > 0; ix--) {
	    if (SvIMMORTAL(PL_curpad[ix]) || IS_PADGV(PL_curpad[ix]) || IS_PADCONST(PL_curpad[ix]))
		continue;
	    if (!SvPADMY(PL_curpad[ix])) {
		SvPADTMP_on(PL_curpad[ix]);
	    } else if (!SvFAKE(namep[ix])) {
		/* This is a work around for how the current implementation of
		   ?{ } blocks in regexps interacts with lexicals.

		   One of our lexicals.
		   Can't do this on all lexicals, otherwise sub baz() won't
		   compile in

		   my $foo;

		   sub bar { ++$foo; }

		   sub baz { ++$foo; }

		   because completion of compiling &bar calling pad_tidy()
		   would cause (top level) $foo to be marked as stale, and
		   "no longer available".  */
		SvPADSTALE_on(PL_curpad[ix]);
	    }
	}
    }
    PL_curpad = AvARRAY(PL_comppad);
}


/*
=for apidoc pad_free

Free the SV at offset po in the current pad.

=cut
*/

/* XXX DAPM integrate with pad_swipe ???? */
void
Perl_pad_free(pTHX_ PADOFFSET po)
{
    dVAR;
    ASSERT_CURPAD_LEGAL("pad_free");
    if (!PL_curpad)
	return;
    if (AvARRAY(PL_comppad) != PL_curpad)
	Perl_croak(aTHX_ "panic: pad_free curpad");
    if (!po)
	Perl_croak(aTHX_ "panic: pad_free po");

    DEBUG_X(PerlIO_printf(Perl_debug_log,
	    "Pad 0x%"UVxf"[0x%"UVxf"] free:    %ld\n",
	    PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po)
    );

    if (PL_curpad[po] && PL_curpad[po] != &PL_sv_undef) {
	SvPADTMP_off(PL_curpad[po]);
#ifdef USE_ITHREADS
	/* SV could be a shared hash key (eg bugid #19022) */
	if (!SvIsCOW(PL_curpad[po]))
	    SvREADONLY_off(PL_curpad[po]);	/* could be a freed constant */
#endif
    }
    if ((I32)po < PL_padix)
	PL_padix = po - 1;
}



/*
=for apidoc do_dump_pad

Dump the contents of a padlist

=cut
*/

void
Perl_do_dump_pad(pTHX_ I32 level, PerlIO *file, PADLIST *padlist, int full)
{
    dVAR;
    const AV *pad_name;
    const AV *pad;
    SV **pname;
    SV **ppad;
    I32 ix;

    PERL_ARGS_ASSERT_DO_DUMP_PAD;

    if (!padlist) {
	return;
    }
    pad_name = MUTABLE_AV(*av_fetch(MUTABLE_AV(padlist), 0, FALSE));
    pad = MUTABLE_AV(*av_fetch(MUTABLE_AV(padlist), 1, FALSE));
    pname = AvARRAY(pad_name);
    ppad = AvARRAY(pad);
    Perl_dump_indent(aTHX_ level, file,
	    "PADNAME = 0x%"UVxf"(0x%"UVxf") PAD = 0x%"UVxf"(0x%"UVxf")\n",
	    PTR2UV(pad_name), PTR2UV(pname), PTR2UV(pad), PTR2UV(ppad)
    );

    for (ix = 1; ix <= AvFILLp(pad_name); ix++) {
        const SV *namesv = pname[ix];
	if (namesv && namesv == &PL_sv_undef) {
	    namesv = NULL;
	}
	if (namesv) {
	    if (SvFAKE(namesv))
		Perl_dump_indent(aTHX_ level+1, file,
		    "%2d. 0x%"UVxf"<%lu> FAKE \"%s\" flags=0x%lx index=%lu\n",
		    (int) ix,
		    PTR2UV(ppad[ix]),
		    (unsigned long) (ppad[ix] ? SvREFCNT(ppad[ix]) : 0),
		    SvPVX_const(namesv),
		    (unsigned long)PARENT_FAKELEX_FLAGS(namesv),
		    (unsigned long)PARENT_PAD_INDEX(namesv)

		);
	    else
		Perl_dump_indent(aTHX_ level+1, file,
		    "%2d. 0x%"UVxf"<%lu> (%lu,%lu) \"%s\"\n",
		    (int) ix,
		    PTR2UV(ppad[ix]),
		    (unsigned long) (ppad[ix] ? SvREFCNT(ppad[ix]) : 0),
		    (unsigned long)COP_SEQ_RANGE_LOW(namesv),
		    (unsigned long)COP_SEQ_RANGE_HIGH(namesv),
		    SvPVX_const(namesv)
		);
	}
	else if (full) {
	    Perl_dump_indent(aTHX_ level+1, file,
		"%2d. 0x%"UVxf"<%lu>\n",
		(int) ix,
		PTR2UV(ppad[ix]),
		(unsigned long) (ppad[ix] ? SvREFCNT(ppad[ix]) : 0)
	    );
	}
    }
}



/*
=for apidoc cv_dump

dump the contents of a CV

=cut
*/

#ifdef DEBUGGING
STATIC void
S_cv_dump(pTHX_ const CV *cv, const char *title)
{
    dVAR;
    const CV * const outside = CvOUTSIDE(cv);
    AV* const padlist = CvPADLIST(cv);

    PERL_ARGS_ASSERT_CV_DUMP;

    PerlIO_printf(Perl_debug_log,
		  "  %s: CV=0x%"UVxf" (%s), OUTSIDE=0x%"UVxf" (%s)\n",
		  title,
		  PTR2UV(cv),
		  (CvANON(cv) ? "ANON"
		   : (SvTYPE(cv) == SVt_PVFM) ? "FORMAT"
		   : (cv == PL_main_cv) ? "MAIN"
		   : CvUNIQUE(cv) ? "UNIQUE"
		   : CvGV(cv) ? GvNAME(CvGV(cv)) : "UNDEFINED"),
		  PTR2UV(outside),
		  (!outside ? "null"
		   : CvANON(outside) ? "ANON"
		   : (outside == PL_main_cv) ? "MAIN"
		   : CvUNIQUE(outside) ? "UNIQUE"
		   : CvGV(outside) ? GvNAME(CvGV(outside)) : "UNDEFINED"));

    PerlIO_printf(Perl_debug_log,
		    "    PADLIST = 0x%"UVxf"\n", PTR2UV(padlist));
    do_dump_pad(1, Perl_debug_log, padlist, 1);
}
#endif /* DEBUGGING */





/*
=for apidoc cv_clone

Clone a CV: make a new CV which points to the same code etc, but which
has a newly-created pad built by copying the prototype pad and capturing
any outer lexicals.

=cut
*/

CV *
Perl_cv_clone(pTHX_ CV *proto)
{
    dVAR;
    I32 ix;
    AV* const protopadlist = CvPADLIST(proto);
    const AV *const protopad_name = (const AV *)*av_fetch(protopadlist, 0, FALSE);
    const AV *const protopad = (const AV *)*av_fetch(protopadlist, 1, FALSE);
    SV** const pname = AvARRAY(protopad_name);
    SV** const ppad = AvARRAY(protopad);
    const I32 fname = AvFILLp(protopad_name);
    const I32 fpad = AvFILLp(protopad);
    CV* cv;
    SV** outpad;
    CV* outside;
    long depth;

    PERL_ARGS_ASSERT_CV_CLONE;

    assert(!CvUNIQUE(proto));

    /* Since cloneable anon subs can be nested, CvOUTSIDE may point
     * to a prototype; we instead want the cloned parent who called us.
     * Note that in general for formats, CvOUTSIDE != find_runcv */

    outside = CvOUTSIDE(proto);
    if (outside && CvCLONE(outside) && ! CvCLONED(outside))
	outside = find_runcv(NULL);
    depth = CvDEPTH(outside);
    assert(depth || SvTYPE(proto) == SVt_PVFM);
    if (!depth)
	depth = 1;
    assert(CvPADLIST(outside));

    ENTER;
    SAVESPTR(PL_compcv);

    cv = PL_compcv = MUTABLE_CV(newSV_type(SvTYPE(proto)));
    CvFLAGS(cv) = CvFLAGS(proto) & ~(CVf_CLONE|CVf_WEAKOUTSIDE|CVf_CVGV_RC);
    CvCLONED_on(cv);

#ifdef USE_ITHREADS
    CvFILE(cv)		= CvISXSUB(proto) ? CvFILE(proto)
					  : savepv(CvFILE(proto));
#else
    CvFILE(cv)		= CvFILE(proto);
#endif
    CvGV_set(cv,CvGV(proto));
    CvSTASH_set(cv, CvSTASH(proto));
    OP_REFCNT_LOCK;
    CvROOT(cv)		= OpREFCNT_inc(CvROOT(proto));
    OP_REFCNT_UNLOCK;
    CvSTART(cv)		= CvSTART(proto);
    CvOUTSIDE(cv)	= MUTABLE_CV(SvREFCNT_inc_simple(outside));
    CvOUTSIDE_SEQ(cv) = CvOUTSIDE_SEQ(proto);

    if (SvPOK(proto))
	sv_setpvn(MUTABLE_SV(cv), SvPVX_const(proto), SvCUR(proto));

    CvPADLIST(cv) = pad_new(padnew_CLONE|padnew_SAVE);

    av_fill(PL_comppad, fpad);
    for (ix = fname; ix >= 0; ix--)
	av_store(PL_comppad_name, ix, SvREFCNT_inc(pname[ix]));

    PL_curpad = AvARRAY(PL_comppad);

    outpad = AvARRAY(AvARRAY(CvPADLIST(outside))[depth]);

    for (ix = fpad; ix > 0; ix--) {
	SV* const namesv = (ix <= fname) ? pname[ix] : NULL;
	SV *sv = NULL;
	if (namesv && namesv != &PL_sv_undef) { /* lexical */
	    if (SvFAKE(namesv)) {   /* lexical from outside? */
		sv = outpad[PARENT_PAD_INDEX(namesv)];
		assert(sv);
		/* formats may have an inactive parent,
		   while my $x if $false can leave an active var marked as
		   stale. And state vars are always available */
		if (SvPADSTALE(sv) && !SvPAD_STATE(namesv)) {
		    Perl_ck_warner(aTHX_ packWARN(WARN_CLOSURE),
				   "Variable \"%s\" is not available", SvPVX_const(namesv));
		    sv = NULL;
		}
		else 
		    SvREFCNT_inc_simple_void_NN(sv);
	    }
	    if (!sv) {
                const char sigil = SvPVX_const(namesv)[0];
                if (sigil == '&')
		    sv = SvREFCNT_inc(ppad[ix]);
                else if (sigil == '@')
		    sv = MUTABLE_SV(newAV());
                else if (sigil == '%')
		    sv = MUTABLE_SV(newHV());
		else
		    sv = newSV(0);
		SvPADMY_on(sv);
		/* reset the 'assign only once' flag on each state var */
		if (SvPAD_STATE(namesv))
		    SvPADSTALE_on(sv);
	    }
	}
	else if (IS_PADGV(ppad[ix]) || IS_PADCONST(ppad[ix])) {
	    sv = SvREFCNT_inc_NN(ppad[ix]);
	}
	else {
	    sv = newSV(0);
	    SvPADTMP_on(sv);
	}
	PL_curpad[ix] = sv;
    }

    DEBUG_Xv(
	PerlIO_printf(Perl_debug_log, "\nPad CV clone\n");
	cv_dump(outside, "Outside");
	cv_dump(proto,	 "Proto");
	cv_dump(cv,	 "To");
    );

    LEAVE;

    if (CvCONST(cv)) {
	/* Constant sub () { $x } closing over $x - see lib/constant.pm:
	 * The prototype was marked as a candiate for const-ization,
	 * so try to grab the current const value, and if successful,
	 * turn into a const sub:
	 */
	SV* const const_sv = op_const_sv(CvSTART(cv), cv);
	if (const_sv) {
	    SvREFCNT_dec(cv);
	    cv = newCONSTSUB(CvSTASH(proto), NULL, const_sv);
	}
	else {
	    CvCONST_off(cv);
	}
    }

    return cv;
}


/*
=for apidoc pad_fixup_inner_anons

For any anon CVs in the pad, change CvOUTSIDE of that CV from
old_cv to new_cv if necessary. Needed when a newly-compiled CV has to be
moved to a pre-existing CV struct.

=cut
*/

void
Perl_pad_fixup_inner_anons(pTHX_ PADLIST *padlist, CV *old_cv, CV *new_cv)
{
    dVAR;
    I32 ix;
    AV * const comppad_name = MUTABLE_AV(AvARRAY(padlist)[0]);
    AV * const comppad = MUTABLE_AV(AvARRAY(padlist)[1]);
    SV ** const namepad = AvARRAY(comppad_name);
    SV ** const curpad = AvARRAY(comppad);

    PERL_ARGS_ASSERT_PAD_FIXUP_INNER_ANONS;
    PERL_UNUSED_ARG(old_cv);

    for (ix = AvFILLp(comppad_name); ix > 0; ix--) {
        const SV * const namesv = namepad[ix];
	if (namesv && namesv != &PL_sv_undef
	    && *SvPVX_const(namesv) == '&')
	{
	    CV * const innercv = MUTABLE_CV(curpad[ix]);
	    assert(CvWEAKOUTSIDE(innercv));
	    assert(CvOUTSIDE(innercv) == old_cv);
	    CvOUTSIDE(innercv) = new_cv;
	}
    }
}


/*
=for apidoc pad_push

Push a new pad frame onto the padlist, unless there's already a pad at
this depth, in which case don't bother creating a new one.  Then give
the new pad an @_ in slot zero.

=cut
*/

void
Perl_pad_push(pTHX_ PADLIST *padlist, int depth)
{
    dVAR;

    PERL_ARGS_ASSERT_PAD_PUSH;

    if (depth > AvFILLp(padlist)) {
	SV** const svp = AvARRAY(padlist);
	AV* const newpad = newAV();
	SV** const oldpad = AvARRAY(svp[depth-1]);
	I32 ix = AvFILLp((const AV *)svp[1]);
        const I32 names_fill = AvFILLp((const AV *)svp[0]);
	SV** const names = AvARRAY(svp[0]);
	AV *av;

	for ( ;ix > 0; ix--) {
	    if (names_fill >= ix && names[ix] != &PL_sv_undef) {
		const char sigil = SvPVX_const(names[ix])[0];
		if ((SvFLAGS(names[ix]) & SVf_FAKE)
			|| (SvFLAGS(names[ix]) & SVpad_STATE)
			|| sigil == '&')
		{
		    /* outer lexical or anon code */
		    av_store(newpad, ix, SvREFCNT_inc(oldpad[ix]));
		}
		else {		/* our own lexical */
		    SV *sv; 
		    if (sigil == '@')
			sv = MUTABLE_SV(newAV());
		    else if (sigil == '%')
			sv = MUTABLE_SV(newHV());
		    else
			sv = newSV(0);
		    av_store(newpad, ix, sv);
		    SvPADMY_on(sv);
		}
	    }
	    else if (IS_PADGV(oldpad[ix]) || IS_PADCONST(oldpad[ix])) {
		av_store(newpad, ix, SvREFCNT_inc_NN(oldpad[ix]));
	    }
	    else {
		/* save temporaries on recursion? */
		SV * const sv = newSV(0);
		av_store(newpad, ix, sv);
		SvPADTMP_on(sv);
	    }
	}
	av = newAV();
	av_store(newpad, 0, MUTABLE_SV(av));
	AvREIFY_only(av);

	av_store(padlist, depth, MUTABLE_SV(newpad));
	AvFILLp(padlist) = depth;
    }
}


HV *
Perl_pad_compname_type(pTHX_ const PADOFFSET po)
{
    dVAR;
    SV* const * const av = av_fetch(PL_comppad_name, po, FALSE);
    if ( SvPAD_TYPED(*av) ) {
        return SvSTASH(*av);
    }
    return NULL;
}

#if defined(USE_ITHREADS)

#  define av_dup_inc(s,t)	MUTABLE_AV(sv_dup_inc((const SV *)s,t))

AV *
Perl_padlist_dup(pTHX_ AV *const srcpad, CLONE_PARAMS *const param)
{
    AV *dstpad;
    PERL_ARGS_ASSERT_PADLIST_DUP;

    if (!srcpad)
	return NULL;

    assert(!AvREAL(srcpad));

    if (param->flags & CLONEf_COPY_STACKS
	|| SvREFCNT(AvARRAY(srcpad)[1]) > 1) {
	/* XXX padlists are real, but pretend to be not */
	AvREAL_on(srcpad);
	dstpad = av_dup_inc(srcpad, param);
	AvREAL_off(srcpad);
	AvREAL_off(dstpad);
	assert (SvREFCNT(AvARRAY(srcpad)[1]) == 1);
    } else {
	/* CvDEPTH() on our subroutine will be set to 0, so there's no need
	   to build anything other than the first level of pads.  */

	I32 ix = AvFILLp((const AV *)AvARRAY(srcpad)[1]);
	AV *pad1;
	const I32 names_fill = AvFILLp((const AV *)(AvARRAY(srcpad)[0]));
	const AV *const srcpad1 = (const AV *) AvARRAY(srcpad)[1];
	SV **oldpad = AvARRAY(srcpad1);
	SV **names;
	SV **pad1a;
	AV *args;
	/* look for it in the table first.
	   I *think* that it shouldn't be possible to find it there.
	   Well, except for how Perl_sv_compile_2op() "works" :-(   */
	dstpad = (AV*)ptr_table_fetch(PL_ptr_table, srcpad);

	if (dstpad)
	    return dstpad;

	dstpad = newAV();
	ptr_table_store(PL_ptr_table, srcpad, dstpad);
	AvREAL_off(dstpad);
	av_extend(dstpad, 1);
	AvARRAY(dstpad)[0] = MUTABLE_SV(av_dup_inc(AvARRAY(srcpad)[0], param));
	names = AvARRAY(AvARRAY(dstpad)[0]);

	pad1 = newAV();

	av_extend(pad1, ix);
	AvARRAY(dstpad)[1] = MUTABLE_SV(pad1);
	pad1a = AvARRAY(pad1);
	AvFILLp(dstpad) = 1;

	if (ix > -1) {
	    AvFILLp(pad1) = ix;

	    for ( ;ix > 0; ix--) {
		if (!oldpad[ix]) {
		    pad1a[ix] = NULL;
		} else if (names_fill >= ix && names[ix] != &PL_sv_undef) {
		    const char sigil = SvPVX_const(names[ix])[0];
		    if ((SvFLAGS(names[ix]) & SVf_FAKE)
			|| (SvFLAGS(names[ix]) & SVpad_STATE)
			|| sigil == '&')
			{
			    /* outer lexical or anon code */
			    pad1a[ix] = sv_dup_inc(oldpad[ix], param);
			}
		    else {		/* our own lexical */
			if(SvPADSTALE(oldpad[ix]) && SvREFCNT(oldpad[ix]) > 1) {
			    /* This is a work around for how the current
			       implementation of ?{ } blocks in regexps
			       interacts with lexicals.  */
			    pad1a[ix] = sv_dup_inc(oldpad[ix], param);
			} else {
			    SV *sv; 
			    
			    if (sigil == '@')
				sv = MUTABLE_SV(newAV());
			    else if (sigil == '%')
				sv = MUTABLE_SV(newHV());
			    else
				sv = newSV(0);
			    pad1a[ix] = sv;
			    SvPADMY_on(sv);
			}
		    }
		}
		else if (IS_PADGV(oldpad[ix]) || IS_PADCONST(oldpad[ix])) {
		    pad1a[ix] = sv_dup_inc(oldpad[ix], param);
		}
		else {
		    /* save temporaries on recursion? */
		    SV * const sv = newSV(0);
		    pad1a[ix] = sv;

		    /* SvREFCNT(oldpad[ix]) != 1 for some code in threads.xs
		       FIXTHAT before merging this branch.
		       (And I know how to) */
		    if (SvPADMY(oldpad[ix]))
			SvPADMY_on(sv);
		    else
			SvPADTMP_on(sv);
		}
	    }

	    if (oldpad[0]) {
		args = newAV();			/* Will be @_ */
		AvREIFY_only(args);
		pad1a[0] = (SV *)args;
	    }
	}
    }

    return dstpad;
}

#endif

/*
 * Local variables:
 * c-indentation-style: bsd
 * c-basic-offset: 4
 * indent-tabs-mode: t
 * End:
 *
 * ex: set ts=8 sts=4 sw=4 noet:
 */