3 perl571delta - what's new for perl v5.7.2
7 This document describes differences between the 5.7.1 release and the
10 (To view the differences between the 5.6.0 release and the 5.7.0
11 release, see L<perl570delta>. To view the differences between the
12 5.7.0 release and the 5.7.1 release, see L<perl571delta>.)
14 =head1 Security Vulnerability Closed
16 (This change was already made in 5.7.0 but bears repeating here.)
18 A security vulnerability affecting all Perl versions prior to 5.6.1
19 was found in August 2000. The vulnerability does not affect default
20 installations and as far as is known affects only the Linux platform.
22 You should upgrade your Perl to 5.6.1 as soon as possible. Patches
23 for earlier releases exist but they require full recompilation from
24 the source code so 5.6.1 is your best choice.
25 See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
28 =head1 Incompatible Changes
30 =head1 Core Enhancements
32 =head1 Modules and Pragmata
36 =head2 Updated And Improved Modules and Pragmata
38 =head1 Performance Enhancements
40 =head1 Utility Changes
42 =head1 New Documentation
44 =head1 Installation and Configuration Improvements
46 =head2 New Or Improved Platforms
48 =head2 Generic Improvements
50 =head1 Selected Bug Fixes
52 =head2 Platform Specific Changes and Fixes
54 =head1 New or Changed Diagnostics
56 =head1 Changed Internals
58 =head2 Regex pre-/post-compilation items matched up
60 The regex compiler now maintains a structure that identifies nodes in
61 the compiled bytecode with the corresponding syntactic features of the
62 original regex expression. The information is attached to the new
63 C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
70 Note that unlike other sections in this document (which describe
71 changes since 5.7.0) this section is cumulative containing known
72 problems for all the 5.7 releases.
74 =head2 AIX vac 5.0.0.0 May Produce Buggy Code For Perl
76 The AIX C compiler vac version 5.0.0.0 may produce buggy code,
77 resulting in few random tests failing, but when the failing tests
78 are run by hand, they succeed. We suggest upgrading to at least
79 vac version 5.0.1.0, that has been known to compile Perl correctly.
80 "lslpp -L|grep vac.C" will tell you the vac version.
82 =head2 lib/ftmp-security tests warn 'system possibly insecure'
84 Don't panic. Read INSTALL 'make test' section instead.
86 =head2 lib/io_multihomed Fails In LP64-Configured HP-UX
88 The lib/io_multihomed test may hang in HP-UX if Perl has been
89 configured to be 64-bit. Because other 64-bit platforms do not hang in
90 this test, HP-UX is suspect. All other tests pass in 64-bit HP-UX. The
91 test attempts to create and connect to "multihomed" sockets (sockets
92 which have multiple IP addresses).
94 =head2 Test lib/posix Subtest 9 Fails In LP64-Configured HP-UX
96 If perl is configured with -Duse64bitall, the successful result of the
97 subtest 10 of lib/posix may arrive before the successful result of the
98 subtest 9, which confuses the test harness so much that it thinks the
103 The test fails on various platforms (PA64 and IA64 are known), but the
104 exact cause is still being investigated.
106 =head2 Linux With Sfio Fails op/misc Test 48
110 =head2 sigaction test 13 in VMS
112 The test is known to fail; whether it's because of VMS of because
113 of faulty test is not known.
115 =head2 sprintf tests 129 and 130
117 The op/sprintf tests 129 and 130 are known to fail on some platforms.
118 Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
119 The failing platforms do not comply with the ANSI C Standard, line
120 19ff on page 134 of ANSI X3.159 1989 to be exact. (They produce
121 something else than "1" and "-1" when formatting 0.6 and -0.6 using
122 the printf format "%.0f", most often they produce "0" and "-0".)
124 =head2 Failure of Thread tests
126 The subtests 19 and 20 of lib/thr5005.t test are known to fail due to
127 fundamental problems in the 5.005 threading implementation. These are
128 not new failures--Perl 5.005_0x has the same bugs, but didn't have
129 these tests. (Note that support for 5.005-style threading remains
132 =head2 Localising a Tied Variable Leaks Memory
135 tie my %tie_hash => 'Tie::StdHash';
139 local($tie_hash{Foo}) = 1; # leaks
141 Code like the above is known to leak memory every time the local()
144 =head2 Self-tying of Arrays and Hashes Is Forbidden
146 Self-tying of arrays and hashes is broken in rather deep and
147 hard-to-fix ways. As a stop-gap measure to avoid people from getting
148 frustrated at the mysterious results (core dumps, most often) it is
149 for now forbidden (you will get a fatal error even from an attempt).
151 =head2 Building Extensions Can Fail Because Of Largefiles
153 Some extensions like mod_perl are known to have issues with
154 `largefiles', a change brought by Perl 5.6.0 in which file offsets
155 default to 64 bits wide, where supported. Modules may fail to compile
156 at all or compile and work incorrectly. Currently there is no good
157 solution for the problem, but Configure now provides appropriate
158 non-largefile ccflags, ldflags, libswanted, and libs in the %Config
159 hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
160 having problems can try configuring themselves without the
161 largefileness. This is admittedly not a clean solution, and the
162 solution may not even work at all. One potential failure is whether
163 one can (or, if one can, whether it's a good idea) link together at
164 all binaries with different ideas about file offsets, all this is
167 =head2 The Compiler Suite Is Still Experimental
169 The compiler suite is slowly getting better but is nowhere near
172 =head1 Reporting Bugs
174 If you find what you think is a bug, you might check the articles
175 recently posted to the comp.lang.perl.misc newsgroup and the perl
176 bug database at http://bugs.perl.org. There may also be
177 information at http://www.perl.com/perl/, the Perl Home Page.
179 If you believe you have an unreported bug, please run the B<perlbug>
180 program included with your release. Be sure to trim your bug down
181 to a tiny but sufficient test case. Your bug report, along with the
182 output of C<perl -V>, will be sent off to perlbug@perl.org to be
183 analysed by the Perl porting team.
187 The F<Changes> file for exhaustive details on what changed.
189 The F<INSTALL> file for how to build Perl.
191 The F<README> file for general stuff.
193 The F<Artistic> and F<Copying> files for copyright information.
197 Written by Jarkko Hietaniemi <F<jhi@iki.fi>>, with many contributions
198 from The Perl Porters and Perl Users submitting feedback and patches.
200 Send omissions or corrections to <F<perlbug@perl.org>>.