5 perl5262delta - what is new for perl v5.26.2
9 This document describes differences between the 5.26.1 release and the 5.26.2
12 If you are upgrading from an earlier release such as 5.26.0, first read
13 L<perl5261delta>, which describes differences between 5.26.0 and 5.26.1.
17 =head2 [CVE-2018-6797] heap-buffer-overflow (WRITE of size 1) in S_regatom (regcomp.c)
19 A crafted regular expression could cause a heap buffer write overflow, with
20 control over the bytes written.
21 L<[perl #132227]|https://rt.perl.org/Public/Bug/Display.html?id=132227>
23 =head2 [CVE-2018-6798] Heap-buffer-overflow in Perl__byte_dump_string (utf8.c)
25 Matching a crafted locale dependent regular expression could cause a heap
26 buffer read overflow and potentially information disclosure.
27 L<[perl #132063]|https://rt.perl.org/Public/Bug/Display.html?id=132063>
29 =head2 [CVE-2018-6913] heap-buffer-overflow in S_pack_rec
31 C<pack()> could cause a heap buffer write overflow with a large item count.
32 L<[perl #131844]|https://rt.perl.org/Public/Bug/Display.html?id=131844>
34 =head2 Assertion failure in Perl__core_swash_init (utf8.c)
36 Control characters in a supposed Unicode property name could cause perl to
37 crash. This has been fixed.
38 L<[perl #132055]|https://rt.perl.org/Public/Bug/Display.html?id=132055>
39 L<[perl #132553]|https://rt.perl.org/Public/Bug/Display.html?id=132553>
40 L<[perl #132658]|https://rt.perl.org/Public/Bug/Display.html?id=132658>
42 =head1 Incompatible Changes
44 There are no changes intentionally incompatible with 5.26.1. If any exist,
45 they are bugs, and we request that you submit a report. See L</Reporting
48 =head1 Modules and Pragmata
50 =head2 Updated Modules and Pragmata
56 L<Module::CoreList> has been upgraded from version 5.20170922_26 to 5.20180414_26.
60 L<PerlIO::via> has been upgraded from version 0.16 to 0.17.
64 L<Term::ReadLine> has been upgraded from version 1.16 to 1.17.
68 L<Unicode::UCD> has been upgraded from version 0.68 to 0.69.
74 =head2 Changes to Existing Documentation
76 =head3 L<perluniprops>
82 This has been updated to note that C<\p{Word}> now includes code points
83 matching the C<\p{Join_Control}> property. The change to the property was made
84 in Perl 5.18, but not documented until now. There are currently only two code
85 points that match this property: U+200C (ZERO WIDTH NON-JOINER) and U+200D
90 =head1 Platform Support
92 =head2 Platform-Specific Notes
98 Visual C++ compiler version detection has been improved to work on non-English
100 L<[perl #132421]|https://rt.perl.org/Public/Bug/Display.html?id=132421>
102 We now set C<$Config{libpth}> correctly for 64-bit builds using Visual C++
103 versions earlier than 14.1.
104 L<[perl #132484]|https://rt.perl.org/Public/Bug/Display.html?id=132484>
108 =head1 Selected Bug Fixes
114 The C<readpipe()> built-in function now checks at compile time that it has only
115 one parameter expression, and puts it in scalar context, thus ensuring that it
116 doesn't corrupt the stack at runtime.
117 L<[perl #4574]|https://rt.perl.org/Public/Bug/Display.html?id=4574>
121 Fixed a use after free bug in C<pp_list> introduced in Perl 5.27.1.
122 L<[perl #131954]|https://rt.perl.org/Public/Bug/Display.html?id=131954>
126 Parsing a C<sub> definition could cause a use after free if the C<sub> keyword
127 was followed by whitespace including newlines (and comments).
128 L<[perl #131836]|https://rt.perl.org/Public/Bug/Display.html?id=131836>
132 The tokenizer now correctly adjusts a parse pointer when skipping whitespace in
133 an C< ${identifier} > construct.
134 L<[perl #131949]|https://rt.perl.org/Public/Bug/Display.html?id=131949>
138 Accesses to C<${^LAST_FH}> no longer assert after using any of a variety of I/O
139 operations on a non-glob.
140 L<[perl #128263]|https://rt.perl.org/Public/Bug/Display.html?id=128263>
144 C<sort> now performs correct reference counting when aliasing C<$a> and C<$b>,
145 thus avoiding premature destruction and leakage of scalars if they are
146 re-aliased during execution of the sort comparator.
147 L<[perl #92264]|https://rt.perl.org/Public/Bug/Display.html?id=92264>
151 Some convoluted kinds of regexp no longer cause an arithmetic overflow when
153 L<[perl #131893]|https://rt.perl.org/Public/Bug/Display.html?id=131893>
157 Fixed a duplicate symbol failure with B<-flto -mieee-fp> builds. F<pp.c>
158 defined C<_LIB_VERSION> which B<-lieee> already defines.
159 L<[perl #131786]|https://rt.perl.org/Public/Bug/Display.html?id=131786>
163 A NULL pointer dereference in the C<S_regmatch()> function has been fixed.
164 L<[perl #132017]|https://rt.perl.org/Public/Bug/Display.html?id=132017>
168 Failures while compiling code within other constructs, such as with string
169 interpolation and the right part of C<s///e> now cause compilation to abort
172 Previously compilation could continue in order to report other errors, but the
173 failed sub-parse could leave partly parsed constructs on the parser
174 shift-reduce stack, confusing the parser, leading to perl crashes.
175 L<[perl #125351]|https://rt.perl.org/Public/Bug/Display.html?id=125351>
179 =head1 Acknowledgements
181 Perl 5.26.2 represents approximately 7 months of development since Perl 5.26.1
182 and contains approximately 3,300 lines of changes across 82 files from 17
185 Excluding auto-generated files, documentation and release tools, there were
186 approximately 1,800 lines of changes to 36 .pm, .t, .c and .h files.
188 Perl continues to flourish into its third decade thanks to a vibrant community
189 of users and developers. The following people are known to have contributed
190 the improvements that became Perl 5.26.2:
192 Aaron Crane, Abigail, Chris 'BinGOs' Williams, H.Merijn Brand, James E Keenan,
193 Jarkko Hietaniemi, John SJ Anderson, Karen Etheridge, Karl Williamson, Lukas
194 Mai, Renee Baecker, Sawyer X, Steve Hay, Todd Rinaldo, Tony Cook, Yves Orton,
197 The list above is almost certainly incomplete as it is automatically generated
198 from version control history. In particular, it does not include the names of
199 the (very much appreciated) contributors who reported issues to the Perl bug
202 Many of the changes included in this version originated in the CPAN modules
203 included in Perl's core. We're grateful to the entire CPAN community for
204 helping Perl to flourish.
206 For a more complete list of all of Perl's historical contributors, please see
207 the F<AUTHORS> file in the Perl source distribution.
209 =head1 Reporting Bugs
211 If you find what you think is a bug, you might check the perl bug database
212 at L<https://rt.perl.org/> . There may also be information at
213 L<http://www.perl.org/> , the Perl Home Page.
215 If you believe you have an unreported bug, please run the L<perlbug> program
216 included with your release. Be sure to trim your bug down to a tiny but
217 sufficient test case. Your bug report, along with the output of C<perl -V>,
218 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
220 If the bug you are reporting has security implications which make it
221 inappropriate to send to a publicly archived mailing list, then see
222 L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
223 for details of how to report the issue.
227 If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
228 you can do so by running the C<perlthanks> program:
232 This will send an email to the Perl 5 Porters list with your show of thanks.
236 The F<Changes> file for an explanation of how to view exhaustive details on
239 The F<INSTALL> file for how to build Perl.
241 The F<README> file for general stuff.
243 The F<Artistic> and F<Copying> files for copyright information.