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43d4bbc8 1=head1 NAME
2
d5f2cb03 3perl572delta - what's new for perl v5.7.2
43d4bbc8 4
5=head1 DESCRIPTION
6
7This document describes differences between the 5.7.1 release and the
85.7.2 release.
9
10(To view the differences between the 5.6.0 release and the 5.7.0
11release, see L<perl570delta>. To view the differences between the
125.7.0 release and the 5.7.1 release, see L<perl571delta>.)
13
14=head1 Security Vulnerability Closed
15
16(This change was already made in 5.7.0 but bears repeating here.)
17
18A security vulnerability affecting all Perl versions prior to 5.6.1
19was found in August 2000. The vulnerability does not affect default
20installations and as far as is known affects only the Linux platform.
21
22You should upgrade your Perl to 5.6.1 as soon as possible. Patches
267a12e6 23for earlier releases exist but using the patches require full
24recompilation from the source code anyway, so 5.6.1 is your best
25choice.
26
43d4bbc8 27See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
28for more information.
29
30=head1 Incompatible Changes
31
699e893f 32=head2 64-bit platforms and malloc
33
267a12e6 34If your pointers are 64 bits wide, the Perl malloc is no more being
35used because it simply does not work with 8-byte pointers. Also,
36usually the system malloc on such platforms are much better optimized
37for such large memory models than the Perl malloc.
38
d7b629d9 39=head2 AIX Dynaloading
40
12f54d27 41The AIX dynaloading now uses in AIX releases 4.3 and newer the native
42dlopen interface of AIX instead of the old emulated interface. This
43change will probably break backward compatibility with compiled
44modules. The change was made to make Perl more compliant with other
45applications like modperl which are using the AIX native interface.
d7b629d9 46
47=head2 Socket Extension Dynamic in VMS
48
49The Socket extension is now dynamically loaded instead of being
50statically built in. This may or may not be a problem with ancient
51TCP/IP stacks of VMS: we do not know since we weren't able to test
52Perl in such configurations.
53
2796c109 54=head2 Different Definition of the Unicode Character Classes \p{In...}
55
56As suggested by the Unicode consortium, the Unicode character classes
57now prefer I<scripts> as opposed to I<blocks> (as defined by Unicode);
58in Perl, when the C<\p{In....}> and the C<\p{In....}> regular expression
59constructs are used. This has changed the definition of some of those
60character classes.
61
62The difference between scripts and blocks is that scripts are the
63glyphs used by a language or a group of languages, while the blocks
64are more artificial groupings of 256 characters based on the Unicode
65numbering.
66
67In general this change results in more inclusive Unicode character
68classes, but changes to the other direction also do take place:
69for example while the script C<Latin> includes all the Latin
70characters and their various diacritic-adorned versions, it
71does not include the various punctuation or digits (since they
72are not solely C<Latin>).
73
74Changes in the character class semantics may have happened if a script
75and a block happen to have the same name, for example C<Hebrew>.
76In such cases the script wins and C<\p{InHebrew}> now means the script
77definition of Hebrew. The block definition in still available,
78though, by appending C<Block> to the name: C<\p{InHebrewBlock}> means
79what C<\p{InHebrew}> meant in perl 5.6.0. For the full list
80of affected character classes, see L<perlunicode/Blocks>.
81
d7b629d9 82=head2 Deprecations
cbb3fa72 83
84The current user-visible implementation of pseudo-hashes (the weird
85use of the first array element) is deprecated starting from Perl 5.8.0
d7b629d9 86and will be removed in Perl 5.10.0, and the feature will be
87implemented differently. Not only is the current interface rather
88ugly, but the current implementation slows down normal array and hash
d0c93ae9 89use quite noticeably. The C<fields> pragma interface will remain
d7b629d9 90available.
91
92The syntaxes C<@a->[...]> and C<@h->{...}> have now been deprecated.
cbb3fa72 93
267a12e6 94The suidperl is also considered to be too much a risk to continue
95maintaining and the suidperl code is likely to be removed in a future
96release.
97
d0c93ae9 98The C<package;> syntax (C<package> without an argument has been
99deprecated. Its semantics were never that clear and its
100implementation even less so. If you have used that feature to
101disallow all but fully qualified variables, C<use strict;> instead.
102
35ae6b54 103The chdir(undef) and chdir('') behaviors to match chdir() has been
104deprecated. In future versions, chdir(undef) and chdir('') will
105simply fail.
106
43d4bbc8 107=head1 Core Enhancements
108
d7b629d9 109In general a lot of fixing has happened in the area of Perl's
110understanding of numbers, both integer and floating point. Since in
111many systems the standard number parsing functions like C<strtoul()>
112and C<atof()> seem to have bugs, Perl tries to work around their
113deficiencies. This results hopefully in more accurate numbers.
267a12e6 114
115=over 4
116
117=item *
118
119The rules for allowing underscores (underbars) in numeric constants
120have been relaxed and simplified: now you can have an underscore
121B<between digits>.
122
123=item *
124
9108dd47 125GMAGIC (right-hand side magic) could in many cases such as string
126concatenation be invoked too many times.
267a12e6 127
128=item *
129
d7b629d9 130Lexicals I: lexicals outside an eval "" weren't resolved
131correctly inside a subroutine definition inside the eval "" if they
132were not already referenced in the top level of the eval""ed code.
133
134=item *
135
136Lexicals II: lexicals leaked at file scope into subroutines that
137were declared before the lexicals.
138
139=item *
140
141Lvalue subroutines can now return C<undef> in list context.
267a12e6 142
143=item *
144
9108dd47 145The C<op_clear> and C<op_null> are now exported.
267a12e6 146
147=item *
148
9108dd47 149A new special regular expression variable has been introduced:
150C<$^N>, which contains the most-recently closed group (submatch).
267a12e6 151
152=item *
153
699e893f 154L<utime> now supports C<utime undef, undef, @files> to change the
d7b629d9 155file timestamps to the current time.
699e893f 156
157=item *
158
267a12e6 159The Perl parser has been stress tested using both random input and
160Markov chain input.
161
d7b629d9 162=item *
163
164C<eval "v200"> now works.
165
166=item *
167
168VMS now works under PerlIO.
169
d95b23b2 170=item *
171
172END blocks are now run even if you exit/die in a BEGIN block.
173The execution of END blocks is now controlled by
174PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
175behaviour for perl embedders. This will default in 5.10. See
176L<perlembed>.
177
267a12e6 178=back
179
43d4bbc8 180=head1 Modules and Pragmata
181
b4d12dfd 182=head2 New Modules and Distributions
43d4bbc8 183
267a12e6 184=over 4
185
186=item *
187
699e893f 188L<Attribute::Handlers> - Simpler definition of attribute handlers
189
190=item *
191
192L<ExtUtils::Constant> - generate XS code to import C header constants
193
194=item *
195
4bbcc6e8 196L<I18N::Langinfo> - query locale information
197
198=item *
199
699e893f 200L<I18N::LangTags> - functions for dealing with RFC3066-style language tags
201
202=item *
203
204L<libnet> - a collection of perl5 modules related to network programming
267a12e6 205
d7b629d9 206Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
207
267a12e6 208=item *
209
699e893f 210L<List::Util> - selection of general-utility list subroutines
267a12e6 211
212=item *
213
699e893f 214L<Locale::Maketext> - framework for localization
267a12e6 215
216=item *
217
699e893f 218L<Memoize> - Make your functions faster by trading space for time
267a12e6 219
220=item *
221
699e893f 222L<NEXT> - pseudo-class for method redispatch
267a12e6 223
224=item *
225
699e893f 226L<Scalar::Util> - selection of general-utility scalar subroutines
267a12e6 227
228=item *
229
7117b917 230L<Test::More> - yet another framework for writing test scripts
231
232=item *
233
234L<Test::Simple> - Basic utilities for writing tests
235
236=item *
237
699e893f 238L<Time::HiRes> - high resolution ualarm, usleep, and gettimeofday
267a12e6 239
240=item *
241
699e893f 242L<Time::Piece> - Object Oriented time objects
267a12e6 243
d7b629d9 244(Previously known as L<Time::Object>.)
245
b4d12dfd 246=item *
247
248L<Time::Seconds> - a simple API to convert seconds to other date values
249
250=item *
251
1189d1e4 252L<UnicodeCD> - Unicode Character Database
b4d12dfd 253
267a12e6 254=back
255
43d4bbc8 256=head2 Updated And Improved Modules and Pragmata
257
267a12e6 258=over 4
259
260=item *
261
262L<B::Deparse> module has been significantly enhanced. It now
263can deparse almost all of the standard test suite (so that the
7ebe6671 264tests still succeed). There is a make target "test.deparse"
265for trying this out.
267a12e6 266
267=item *
268
269L<Class::Struct> now assigns the array/hash element if the accessor
270is called with an array/hash element as the B<sole> argument.
271
272=item *
273
274L<Cwd> extension is now (even) faster.
275
276=item *
277
278L<DB_File> extension has been updated to version 1.77.
279
280=item *
281
282L<Fcntl>, L<Socket>, and L<Sys::Syslog> have been rewritten to use the
283new-style constant dispatch section (see L<ExtUtils::Constant>).
284
285=item *
286
699e893f 287L<File::Find> is now (again) reentrant. It also has been made
288more portable.
289
290=item *
291
267a12e6 292L<File::Glob> now supports C<GLOB_LIMIT> constant to limit the
293size of the returned list of filenames.
294
699e893f 295=item *
267a12e6 296
d7b629d9 297L<IO::Socket::INET> now supports C<LocalPort> of zero (usually meaning
298that the operating system will make one up.)
299
300=item *
301
302The L<vars> pragma now supports declaring fully qualified variables.
303(Something that C<our()> does not and will not support.)
699e893f 304
305=back
43d4bbc8 306
307=head1 Utility Changes
308
267a12e6 309=over 4
310
311=item *
312
699e893f 313The F<emacs/e2ctags.pl> is now much faster.
314
315=item *
316
d7b629d9 317L<h2ph> now supports C trigraphs.
318
319=item *
320
267a12e6 321L<h2xs> uses the new L<ExtUtils::Constant> module which will affect
322newly created extensions that define constants. Since the new code is
323more correct (if you have two constants where the first one is a
324prefix of the second one, the first constant B<never> gets defined),
325less lossy (it uses integers for integer constant, as opposed to the
326old code that used floating point numbers even for integer constants),
327and slightly faster, you might want to consider regenerating your
328extension code (the new scheme makes regenerating easy).
d5f2cb03 329L<h2xs> now also supports C trigraphs.
267a12e6 330
331=item *
332
699e893f 333L<libnetcfg> has been added to configure the libnet.
267a12e6 334
335=item *
336
337The F<Pod::Html> (and thusly L<pod2html>) now allows specifying
338a cache directory.
339
340=back
341
43d4bbc8 342=head1 New Documentation
343
267a12e6 344=over 4
345
346=item *
347
348L<Locale::Maketext::TPJ13> is an article about software localization,
349originally published in The Perl Journal #13, republished here with
350kind permission.
351
352=item *
353
354More README.$PLATFORM files have been converted into pod, which also
355means that they also be installed as perl$PLATFORM documentation
356files. The new files are L<perlapollo>, L<perlbeos>, L<perldgux>,
699e893f 357L<perlhurd>, L<perlmint>, L<perlnetware>, L<perlplan9>, L<perlqnx>,
358and L<perltru64>.
267a12e6 359
360=item *
361
362The F<Todo> and F<Todo-5.6> files have been merged into L<perltodo>.
363
364=item *
365
7ebe6671 366Use of the F<gprof> tool to profile Perl has been documented in
367L<perlhack>. There is a make target "perl.gprof" for generating a
368gprofiled Perl executable.
267a12e6 369
370=back
371
43d4bbc8 372=head1 Installation and Configuration Improvements
373
374=head2 New Or Improved Platforms
375
267a12e6 376=over 4
377
378=item *
379
c033f808 380AIX should now work better with gcc, threads, and 64-bitness. Also the
12f54d27 381long doubles support in AIX should be better now. See L<perlaix>.
267a12e6 382
383=item *
384
385AtheOS (http://www.atheos.cx/) is a new platform.
386
387=item *
388
7ebe6671 389DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
267a12e6 390
391=item *
392
d5f2cb03 393DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
394
395=item *
396
7ebe6671 397Several MacOS (Classic) portability patches have been applied. We
398hope to get a fully working port by 5.8.0. (The remaining problems
399relate to the changed IO model of Perl.) See L<perlmacos>.
267a12e6 400
401=item *
402
699e893f 403MacOS X (or Darwin) should now be able to build Perl even on HFS+
404filesystems. (The case-insensitivity confused the Perl build process.)
267a12e6 405
406=item *
407
7ebe6671 408NetWare from Novell is now supported. See L<perlnetware>.
267a12e6 409
410=item *
411
412The Amdahl UTS UNIX mainframe platform is now supported.
413
414=back
415
43d4bbc8 416=head2 Generic Improvements
417
267a12e6 418=over 4
419
420=item *
421
267a12e6 422In AFS installations one can configure the root of the AFS to be
423somewhere else than the default F</afs> by using the Configure
424parameter C<-Dafsroot=/some/where/else>.
425
426=item *
427
428The version of Berkeley DB used when the Perl (and, presumably, the
429DB_File extension) was built is now available as
430C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
431from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
432DB_VERSION_PATCH_CFG> from C.
433
434=item *
435
699e893f 436The Thread extension is now not built at all under ithreads
437(C<Configure -Duseithreads>) because it wouldn't work anyway (the
438Thread extension requires being Configured with C<-Duse5005threads>).
267a12e6 439
440=item *
441
442The C<B::Deparse> compiler backend has been so significantly improved
443that almost the whole Perl test suite passes after being deparsed. A
444make target has been added to help in further testing: C<make test.deparse>.
445
446=back
447
43d4bbc8 448=head1 Selected Bug Fixes
449
699e893f 450=over 5
451
452=item *
453
454The autouse pragma didn't work for Multi::Part::Function::Names.
455
456=item *
457
458The behaviour of non-decimal but numeric string constants such as
459"0x23" was platform-dependent: in some platforms that was seen as 35,
460in some as 0, in some as a floating point number (don't ask). This
461was caused by Perl using the operating system libraries in a situation
462where the result of the string to number conversion is undefined: now
463Perl consistently handles such strings as zero in numeric contexts.
464
465=item *
466
467L<dprofpp> -R didn't work.
468
469=item *
470
471PERL5OPT with embedded spaces didn't work.
472
473=item *
474
475L<Sys::Syslog> ignored the C<LOG_AUTH> constant.
476
477=back
478
43d4bbc8 479=head2 Platform Specific Changes and Fixes
480
267a12e6 481=over 4
482
483=item *
484
485Some versions of glibc have a broken modfl(). This affects builds
486with C<-Duselongdouble>. This version of Perl detects this brokenness
487and has a workaround for it. The glibc release 2.2.2 is known to have
488fixed the modfl() bug.
489
490=back
491
43d4bbc8 492=head1 New or Changed Diagnostics
493
267a12e6 494=over 4
495
496=item *
497
498In the regular expression diagnostics the C<E<lt>E<lt> HERE> marker
499introduced in 5.7.0 has been changed to be C<E<lt>-- HERE> since too
500many people found the C<E<lt>E<lt>> to be too similar to here-document
501starters.
502
503=item *
504
505If you try to L<perlfunc/pack> a number less than 0 or larger than 255
506using the C<"C"> format you will get an optional warning. Similarly
507for the C<"c"> format and a number less than -128 or more than 127.
508
509=item *
510
511Certain regex modifiers such as C<(?o)> make sense only if applied to
512the entire regex. You will an optional warning if you try to do otherwise.
513
514=item *
515
516Using arrays or hashes as references (e.g. C<%foo->{bar}> has been
517deprecated for a while. Now you will get an optional warning.
518
519=back
520
9108dd47 521=head1 Source Code Enhancements
522
523=head2 MAGIC constants
524
525The MAGIC constants (e.g. C<'P'>) have been macrofied
526(e.g. C<PERL_MAGIC_TIED>) for better source code readability
527and maintainability.
528
529=head2 Better commented code
530
531F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
43d4bbc8 532
533=head2 Regex pre-/post-compilation items matched up
534
535The regex compiler now maintains a structure that identifies nodes in
536the compiled bytecode with the corresponding syntactic features of the
537original regex expression. The information is attached to the new
538C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
539complete information.
540
9108dd47 541=head2 gcc -Wall
542
543The C code has been made much more C<gcc -Wall> clean. Some warning
544messages still remain, though, so if you are compiling with gcc you
545will see some warnings about dubious practices. The warnings are
546being worked on.
547
43d4bbc8 548=head1 New Tests
549
267a12e6 550Several new tests have been added, especially for the F<lib> subsection.
551
699e893f 552The tests are now reported in a different order than in earlier Perls.
553(This happens because the test scripts from under t/lib have been moved
554to be closer to the library/extension they are testing.)
267a12e6 555
43d4bbc8 556=head1 Known Problems
557
558Note that unlike other sections in this document (which describe
559changes since 5.7.0) this section is cumulative containing known
560problems for all the 5.7 releases.
561
81633404 562=head2 AIX
563
564=over 4
565
566=item *
567
d7d85e39 568In AIX 4.2 Perl extensions that use C++ functions that use statics
569may have problems in that the statics are not getting initialized.
570In newer AIX releases this has been solved by linking Perl with
571the libC_r library, but unfortunately in AIX 4.2 the said library
572has an obscure bug where the various functions related to time
573(such as time() and gettimeofday()) return broken values, and
574therefore in AIX 4.2 Perl is not linked against the libC_r.
81633404 575
576=item *
577
578vac 5.0.0.0 May Produce Buggy Code For Perl
43d4bbc8 579
580The AIX C compiler vac version 5.0.0.0 may produce buggy code,
581resulting in few random tests failing, but when the failing tests
582are run by hand, they succeed. We suggest upgrading to at least
583vac version 5.0.1.0, that has been known to compile Perl correctly.
584"lslpp -L|grep vac.C" will tell you the vac version.
585
81633404 586=back
587
d7b629d9 588=head2 Amiga Perl Invoking Mystery
589
590One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
591works, but for example C<bin:perl -v> doesn't. The exact reason is
592known but the current suspect is the F<ixemul> library.
593
43d4bbc8 594=head2 lib/ftmp-security tests warn 'system possibly insecure'
595
596Don't panic. Read INSTALL 'make test' section instead.
597
19d94770 598=head2 Cygwin intermittent failures of lib/Memoize/t/expire_file 11 and 12
81633404 599
600The subtests 11 and 12 sometimes fail and sometimes work.
601
210b36aa 602=head2 HP-UX lib/io_multihomed Fails When LP64-Configured
43d4bbc8 603
604The lib/io_multihomed test may hang in HP-UX if Perl has been
605configured to be 64-bit. Because other 64-bit platforms do not hang in
606this test, HP-UX is suspect. All other tests pass in 64-bit HP-UX. The
607test attempts to create and connect to "multihomed" sockets (sockets
608which have multiple IP addresses).
609
81633404 610=head2 HP-UX lib/posix Subtest 9 Fails When LP64-Configured
43d4bbc8 611
612If perl is configured with -Duse64bitall, the successful result of the
613subtest 10 of lib/posix may arrive before the successful result of the
614subtest 9, which confuses the test harness so much that it thinks the
615subtest 9 failed.
616
43d4bbc8 617=head2 Linux With Sfio Fails op/misc Test 48
618
619No known fix.
620
ee9f9f3a 621=head2 OS/390
622
623OS/390 has rather many test failures but the situation is actually
624better than it was in 5.6.0, it's just that so many new modules and
625tests have been added.
626
627 Failed Test Stat Wstat Total Fail Failed List of Failed
628 -----------------------------------------------------------------------------
629 ../ext/B/Deparse.t 14 1 7.14% 14
630 ../ext/B/Showlex.t 1 1 100.00% 1
631 ../ext/Encode/Encode/Tcl.t 610 13 2.13% 592 594 596 598
632 600 602 604-610
633 ../ext/IO/lib/IO/t/io_unix.t 113 28928 5 3 60.00% 3-5
634 ../ext/POSIX/POSIX.t 29 1 3.45% 14
635 ../ext/Storable/t/lock.t 255 65280 5 3 60.00% 3-5
636 ../lib/locale.t 129 33024 117 19 16.24% 99-117
637 ../lib/warnings.t 434 1 0.23% 75
638 ../lib/ExtUtils.t 27 1 3.70% 25
639 ../lib/Math/BigInt/t/bigintpm.t 1190 1 0.08% 1145
640 ../lib/Unicode/UCD.t 81 48 59.26% 1-16 49-64 66-81
641 ../lib/User/pwent.t 9 1 11.11% 4
642 op/pat.t 660 6 0.91% 242-243 424-425
643 626-627
644 op/split.t 0 9 ?? ?? % ??
645 op/taint.t 174 3 1.72% 156 162 168
646 op/tr.t 70 3 4.29% 50 58-59
647 Failed 16/422 test scripts, 96.21% okay. 105/23251 subtests failed, 99.55% okay.
648
c4b279ff 649=head2 op/sprintf tests 129 and 130
43d4bbc8 650
651The op/sprintf tests 129 and 130 are known to fail on some platforms.
652Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
653The failing platforms do not comply with the ANSI C Standard, line
65419ff on page 134 of ANSI X3.159 1989 to be exact. (They produce
d5f2cb03 655something other than "1" and "-1" when formatting 0.6 and -0.6 using
43d4bbc8 656the printf format "%.0f", most often they produce "0" and "-0".)
657
658=head2 Failure of Thread tests
659
45215428 660B<Note that support for 5.005-style threading remains experimental.>
661
662The following tests are known to fail due to fundamental problems in
663the 5.005 threading implementation. These are not new failures--Perl
6645.005_0x has the same bugs, but didn't have these tests.
665
c4b279ff 666 lib/autouse.t 4
667 t/lib/thr5005.t 19-20
668
81633404 669=head2 UNICOS
670
671=over 4
672
673=item *
674
675ext/POSIX/sigaction subtests 6 and 13 may fail.
676
677=item *
678
679lib/ExtUtils may spuriously claim that subtest 28 failed,
680which is interesting since the test only has 27 tests.
681
682=item *
683
684Numerous numerical test failures
c4b279ff 685
686 op/numconvert 209,210,217,218
81633404 687 op/override 7
c4b279ff 688 ext/Time/HiRes/HiRes 9
689 lib/Math/BigInt/t/bigintpm 1145
690 lib/Math/Trig 25
691
692These tests fail because of yet unresolved floating point inaccuracies.
693
81633404 694=back
695
81633404 696=head2 UTS
697
91144103 698There are a few known test failures, see L<perluts>.
0aa7ccc3 699
700=head2 VMS
701
ee9f9f3a 702Rather many tests are failing in VMS but that actually more tests
703succeed in VMS than they used to, it's just that there are many,
704many more tests than there used to be.
705
706Here are the known failures from some compiler/platform combinations.
707
0aa7ccc3 708DEC C V5.3-006 on OpenVMS VAX V6.2
7207e29d 709
0aa7ccc3 710 [-.ext.list.util.t]tainted..............FAILED on test 3
711 [-.ext.posix]sigaction..................FAILED on test 7
50bd9457 712 [-.ext.time.hires]hires.................FAILED on test 14
0aa7ccc3 713 [-.lib.file.find]taint..................FAILED on test 17
714 [-.lib.math.bigint.t]bigintpm...........FAILED on test 1183
715 [-.lib.test.simple.t]exit...............FAILED on test 1
716 [.lib]vmsish............................FAILED on test 13
717 [.op]sprintf............................FAILED on test 12
718 Failed 8/399 tests, 91.23% okay.
719
d5f2cb03 720DEC C V6.0-001 on OpenVMS Alpha V7.2-1 and
721Compaq C V6.2-008 on OpenVMS Alpha V7.1
0aa7ccc3 722
723 [-.ext.list.util.t]tainted..............FAILED on test 3
724 [-.lib.file.find]taint..................FAILED on test 17
725 [-.lib.test.simple.t]exit...............FAILED on test 1
726 [.lib]vmsish............................FAILED on test 13
727 Failed 4/399 tests, 92.48% okay.
81633404 728
210b36aa 729Compaq C V6.4-005 on OpenVMS Alpha 7.2.1
20a07785 730
731 [-.ext.b]showlex........................FAILED on test 1
732 [-.ext.list.util.t]tainted..............FAILED on test 3
733 [-.lib.file.find]taint..................FAILED on test 17
734 [-.lib.test.simple.t]exit...............FAILED on test 1
735 [.lib]vmsish............................FAILED on test 13
736 [.op]misc...............................FAILED on test 49
737 Failed 6/401 tests, 92.77% okay.
738
d0c93ae9 739=head2 Win32
740
741In multi-CPU boxes there are some problems with the I/O buffering:
742some output may appear twice.
743
43d4bbc8 744=head2 Localising a Tied Variable Leaks Memory
745
746 use Tie::Hash;
747 tie my %tie_hash => 'Tie::StdHash';
748
749 ...
750
751 local($tie_hash{Foo}) = 1; # leaks
752
753Code like the above is known to leak memory every time the local()
754is executed.
755
756=head2 Self-tying of Arrays and Hashes Is Forbidden
757
758Self-tying of arrays and hashes is broken in rather deep and
759hard-to-fix ways. As a stop-gap measure to avoid people from getting
760frustrated at the mysterious results (core dumps, most often) it is
761for now forbidden (you will get a fatal error even from an attempt).
762
699e893f 763=head2 Variable Attributes are not Currently Usable for Tieing
764
765This limitation will hopefully be fixed in future. (Subroutine
766attributes work fine for tieing, see L<Attribute::Handlers>).
767
43d4bbc8 768=head2 Building Extensions Can Fail Because Of Largefiles
769
770Some extensions like mod_perl are known to have issues with
771`largefiles', a change brought by Perl 5.6.0 in which file offsets
772default to 64 bits wide, where supported. Modules may fail to compile
773at all or compile and work incorrectly. Currently there is no good
774solution for the problem, but Configure now provides appropriate
775non-largefile ccflags, ldflags, libswanted, and libs in the %Config
776hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
777having problems can try configuring themselves without the
778largefileness. This is admittedly not a clean solution, and the
779solution may not even work at all. One potential failure is whether
780one can (or, if one can, whether it's a good idea) link together at
781all binaries with different ideas about file offsets, all this is
782platform-dependent.
783
784=head2 The Compiler Suite Is Still Experimental
785
786The compiler suite is slowly getting better but is nowhere near
787working order yet.
788
81633404 789=head2 The Long Double Support is Still Experimental
790
791The ability to configure Perl's numbers to use "long doubles",
792floating point numbers of hopefully better accuracy, is still
793experimental. The implementations of long doubles are not yet
794widespread and the existing implementations are not quite mature
795or standardised, therefore trying to support them is a rare
796and moving target. The gain of more precision may also be offset
797by slowdown in computations (more bits to move around, and the
798operations are more likely to be executed by less optimised
799libraries).
800
43d4bbc8 801=head1 Reporting Bugs
802
803If you find what you think is a bug, you might check the articles
804recently posted to the comp.lang.perl.misc newsgroup and the perl
805bug database at http://bugs.perl.org. There may also be
806information at http://www.perl.com/perl/, the Perl Home Page.
807
808If you believe you have an unreported bug, please run the B<perlbug>
809program included with your release. Be sure to trim your bug down
810to a tiny but sufficient test case. Your bug report, along with the
811output of C<perl -V>, will be sent off to perlbug@perl.org to be
812analysed by the Perl porting team.
813
814=head1 SEE ALSO
815
816The F<Changes> file for exhaustive details on what changed.
817
818The F<INSTALL> file for how to build Perl.
819
820The F<README> file for general stuff.
821
822The F<Artistic> and F<Copying> files for copyright information.
823
824=head1 HISTORY
825
826Written by Jarkko Hietaniemi <F<jhi@iki.fi>>, with many contributions
827from The Perl Porters and Perl Users submitting feedback and patches.
828
829Send omissions or corrections to <F<perlbug@perl.org>>.
830
831=cut