| 1 | =encoding utf8 |
| 2 | |
| 3 | =head1 NAME |
| 4 | |
| 5 | perl5212delta - what is new for perl v5.21.2 |
| 6 | |
| 7 | =head1 DESCRIPTION |
| 8 | |
| 9 | This document describes differences between the 5.21.1 release and the 5.21.2 |
| 10 | release. |
| 11 | |
| 12 | If you are upgrading from an earlier release such as 5.21.0, first read |
| 13 | L<perl5211delta>, which describes differences between 5.21.0 and 5.21.1. |
| 14 | |
| 15 | =head1 Core Enhancements |
| 16 | |
| 17 | =head2 Better heuristics on older platforms for determining locale UTF8ness |
| 18 | |
| 19 | On platforms that implement neither the C99 standard nor the POSIX 2001 |
| 20 | standard, determining if the current locale is UTF8 or not depends on |
| 21 | heuristics. These are improved in this release. |
| 22 | |
| 23 | =head1 Security |
| 24 | |
| 25 | =head2 Perl is now always compiled with -D_FORTIFY_SOURCE=2 if available |
| 26 | |
| 27 | The 'code hardening' option called C<_FORTIFY_SOURCE>, available in |
| 28 | gcc 4.*, is now always used for compiling Perl, if available. |
| 29 | |
| 30 | Note that this isn't necessarily a huge step since in many platforms |
| 31 | the step had already been taken several years ago: many Linux |
| 32 | distributions (like Fedora) have been using this option for Perl, |
| 33 | and OS X has enforced the same for many years. |
| 34 | |
| 35 | |
| 36 | =head1 Deprecations |
| 37 | |
| 38 | =head2 C<< /\C/ >> character class |
| 39 | |
| 40 | This character class, which matches a single byte, even if it appears |
| 41 | in a multi-byte character has been deprecated. Matching single bytes |
| 42 | in a multi-byte character breaks encapsulation, and can corrupt utf8 |
| 43 | strings. |
| 44 | |
| 45 | =head1 Performance Enhancements |
| 46 | |
| 47 | =over 4 |
| 48 | |
| 49 | =item * |
| 50 | |
| 51 | Refactoring of C<< pp_tied >> and CC<< pp_ref >> for small improvements. |
| 52 | |
| 53 | =item * |
| 54 | |
| 55 | Pathtools don't try to load XS on miniperl. |
| 56 | |
| 57 | =item * |
| 58 | |
| 59 | A typo fix reduces the size of the C<< OP >> structure. |
| 60 | |
| 61 | =item * |
| 62 | |
| 63 | Hash lookups where the key is a constant is faster. |
| 64 | |
| 65 | =back |
| 66 | |
| 67 | =head1 Modules and Pragmata |
| 68 | |
| 69 | =head2 Updated Modules and Pragmata |
| 70 | |
| 71 | =over 4 |
| 72 | |
| 73 | =item * |
| 74 | |
| 75 | L<arybase> has been upgraded from version 0.07 to 0.08. |
| 76 | |
| 77 | =item * |
| 78 | |
| 79 | L<B> has been upgraded from version 1.49 to 1.50. |
| 80 | |
| 81 | =item * |
| 82 | |
| 83 | L<Devel::Peek> has been upgraded from version 1.17 to 1.18. |
| 84 | |
| 85 | =item * |
| 86 | |
| 87 | L<experimental> has been upgraded from version 0.007 to 0.008. |
| 88 | |
| 89 | =item * |
| 90 | |
| 91 | L<ExtUtils::Manifest> has been upgraded from version 1.63 to 1.64. |
| 92 | |
| 93 | =item * |
| 94 | |
| 95 | L<File::Copy> has been upgraded from version 2.29 to 2.30. |
| 96 | |
| 97 | =item * |
| 98 | |
| 99 | The PathTools module collection (L<File::Spec> and friends) has been |
| 100 | upgraded from version 3.48 to 3.49. |
| 101 | |
| 102 | =item * |
| 103 | |
| 104 | L<Filter::Simple> has been upgraded from version 0.91 to 0.92. |
| 105 | |
| 106 | =item * |
| 107 | |
| 108 | L<Hash::Util> has been upgraded from version 0.17 to 0.18. |
| 109 | |
| 110 | =item * |
| 111 | |
| 112 | L<IO> has been upgraded from version 1.32 to 1.33. |
| 113 | |
| 114 | =item * |
| 115 | |
| 116 | L<IO::Socket::IP> has been upgraded from version 0.29 to 0.31. |
| 117 | |
| 118 | A better fix for subclassing C<connect()>. |
| 119 | L<[cpan #95983]|https://rt.cpan.org/Ticket/Display.html?id=95983> |
| 120 | L<[cpan #97050]|https://rt.cpan.org/Ticket/Display.html?id=97050> |
| 121 | |
| 122 | =item * |
| 123 | |
| 124 | L<IPC::Open3> has been upgraded from version 1.16 to 1.17. |
| 125 | |
| 126 | =item * |
| 127 | |
| 128 | L<Math::BigInt> has been upgraded from version 1.9995 to 1.9996. |
| 129 | |
| 130 | Correct handling of subclasses. |
| 131 | L<[cpan #96254]|https://rt.cpan.org/Ticket/Display.html?id=96254> |
| 132 | L<[cpan #96329]|https://rt.cpan.org/Ticket/Display.html?id=96329> |
| 133 | |
| 134 | =item * |
| 135 | |
| 136 | L<Module::CoreList> has been upgraded from version 5.021001_01 to 5.021002. |
| 137 | |
| 138 | =item * |
| 139 | |
| 140 | L<Pod::Usage> has been upgraded from version 1.63 to 1.64. |
| 141 | |
| 142 | =item * |
| 143 | |
| 144 | L<POSIX> has been upgraded from version 1.40 to 1.41. |
| 145 | |
| 146 | =item * |
| 147 | |
| 148 | L<threads> has been upgraded from version 1.94 to 1.95. |
| 149 | |
| 150 | =item * |
| 151 | |
| 152 | L<warnings> has been upgraded from version 1.24 to 1.26. |
| 153 | |
| 154 | =back |
| 155 | |
| 156 | =head1 Documentation |
| 157 | |
| 158 | =head2 Changes to Existing Documentation |
| 159 | |
| 160 | =head3 L<< perlpolicy >> |
| 161 | |
| 162 | =over 4 |
| 163 | |
| 164 | =item * |
| 165 | |
| 166 | We now have a code of conduct for the I<< p5p >> mailing list, as documented |
| 167 | in L<< perlpolicy/STANDARDS OF CONDUCT >>. |
| 168 | |
| 169 | =back |
| 170 | |
| 171 | =head3 L<< perlfunc >> |
| 172 | |
| 173 | =over 4 |
| 174 | |
| 175 | =item * |
| 176 | |
| 177 | Improve documentation of C<< our >>. |
| 178 | |
| 179 | =back |
| 180 | |
| 181 | =head3 L<< perlsyn >> |
| 182 | |
| 183 | =over 4 |
| 184 | |
| 185 | =item * |
| 186 | |
| 187 | The empty conditional in C<< for >> and C<< while >> is now documented |
| 188 | in L<< perlsyn >>. |
| 189 | |
| 190 | =back |
| 191 | |
| 192 | =head1 Diagnostics |
| 193 | |
| 194 | =head2 New Diagnostics |
| 195 | |
| 196 | =head3 New Warnings |
| 197 | |
| 198 | =over 4 |
| 199 | |
| 200 | =item * |
| 201 | |
| 202 | L<Argument "%s" treated as 0 in increment (++)|perldiag/"Argument "%s" treated |
| 203 | as 0 in increment (++)"> |
| 204 | |
| 205 | (W numeric) The indicated string was fed as an argument to the C<++> operator |
| 206 | which expects either a number or a string matching C</^[a-zA-Z]*[0-9]*\z/>. |
| 207 | See L<perlop/Auto-increment and Auto-decrement> for details. |
| 208 | |
| 209 | =item * |
| 210 | |
| 211 | L<Redundant argument in %s|perldiag/Redundant argument in %s> |
| 212 | |
| 213 | (W redundant) You called a function with more arguments than other |
| 214 | arguments you supplied indicated would be needed. Currently only |
| 215 | emitted when a printf-type format required fewer arguments than were |
| 216 | supplied, but might be used in the future for e.g. L<perlfunc/pack>. |
| 217 | |
| 218 | The warnings category C<< redundant >> is new. See also [RT #121025] |
| 219 | |
| 220 | =back |
| 221 | |
| 222 | =head1 Configuration and Compilation |
| 223 | |
| 224 | =over 4 |
| 225 | |
| 226 | =item * |
| 227 | |
| 228 | A new compilation flag, C<< -DPERL_OP_PARENT >> is available. For details, |
| 229 | see the discussion below at L<< /Internal Changes >>. |
| 230 | |
| 231 | =back |
| 232 | |
| 233 | =head1 Testing |
| 234 | |
| 235 | =over 4 |
| 236 | |
| 237 | =item * |
| 238 | |
| 239 | C<< test.pl >> now allows C<< plan skip_all => $reason >>, to make it |
| 240 | more compatible with C<< Test::More >>. |
| 241 | |
| 242 | =back |
| 243 | |
| 244 | =head1 Platform Support |
| 245 | |
| 246 | =head2 Platform-Specific Notes |
| 247 | |
| 248 | =over 4 |
| 249 | |
| 250 | =item Solaris |
| 251 | |
| 252 | Builds on Solaris 10 with C<-Dusedtrace> would fail early since make |
| 253 | didn't follow implied dependencies to build C<perldtrace.h>. Added an |
| 254 | explicit dependency to C<depend>. |
| 255 | L<[perl #120120]|https://rt.perl.org/Ticket/Display.html?id=120120> |
| 256 | |
| 257 | =back |
| 258 | |
| 259 | =head1 Internal Changes |
| 260 | |
| 261 | =over 4 |
| 262 | |
| 263 | =item * |
| 264 | |
| 265 | The following private API functions had their context parameter removed, |
| 266 | C<Perl_cast_ulong>, C<Perl_cast_i32>, C<Perl_cast_iv>, C<Perl_cast_uv>, |
| 267 | C<Perl_cv_const_sv>, C<Perl_mg_find>, C<Perl_mg_findext>, C<Perl_mg_magical>, |
| 268 | C<Perl_mini_mktime>, C<Perl_my_dirfd>, C<Perl_sv_backoff>, C<Perl_utf8_hop>. |
| 269 | |
| 270 | Users of the public API prefix-less calls remain unaffected. |
| 271 | |
| 272 | =item * |
| 273 | |
| 274 | Experimental support for ops in the optree to be able to locate their |
| 275 | parent, if any. A general-purpose function, C<< op_sibling_splice() >> |
| 276 | allows for general manipulating an C<< op_sibling >> chain. The last op |
| 277 | in such a chain is now marked with the field C<< op_lastsib >>. |
| 278 | |
| 279 | A new build define, C<< -DPERL_OP_PARENT >> has been added; if |
| 280 | given, it forces the core to use C<< op_lastsib >> to detect the |
| 281 | last sibling in a chain, freeing the last C<< op_sibling >> pointer, |
| 282 | which then points back to the parent (instead of being C<< NULL >>). |
| 283 | |
| 284 | A C-level C<< op_parent() >> function, and a C<< B >> C<< parent() >> method |
| 285 | have been added; under a default build, they return C<< NULL >>, but when |
| 286 | C<< -DPERL_OP_PARENT >> has been set, they return the parent of the current op. |
| 287 | |
| 288 | =back |
| 289 | |
| 290 | =head1 Selected Bug Fixes |
| 291 | |
| 292 | =over 4 |
| 293 | |
| 294 | =item * |
| 295 | |
| 296 | C<< s///e >> on tainted utf8 strings got C<< pos() >> messed up. This bug, |
| 297 | introduced in 5.20, is now fixed. [RT #122148] |
| 298 | |
| 299 | =item * |
| 300 | |
| 301 | A non-word boundary in a regular expression (C<< \B >>) did not always |
| 302 | match the end of the string; in particular C<< q{} =~ /\B/ >> did not |
| 303 | match. This bug, introduced in perl 5.14, is now fixed. [RT #122090] |
| 304 | |
| 305 | =item * |
| 306 | |
| 307 | C<< " P" =~ /(?=.*P)P/ >> should match, but did not. This is now fixed. |
| 308 | [RT #122171]. |
| 309 | |
| 310 | =back |
| 311 | |
| 312 | =head1 Acknowledgements |
| 313 | |
| 314 | Perl 5.21.2 represents approximately 4 weeks of development since Perl 5.21.1 |
| 315 | and contains approximately 11,000 lines of changes across 220 files from 27 |
| 316 | authors. |
| 317 | |
| 318 | Excluding auto-generated files, documentation and release tools, there were |
| 319 | approximately 5,700 lines of changes to 140 .pm, .t, .c and .h files. |
| 320 | |
| 321 | Perl continues to flourish into its third decade thanks to a vibrant community |
| 322 | of users and developers. The following people are known to have contributed the |
| 323 | improvements that became Perl 5.21.2: |
| 324 | |
| 325 | Aaron Crane, Abhijit Menon-Sen, Abigail, Alexandr Ciornii, brian d foy, Brian |
| 326 | Fraser, Chris 'BinGOs' Williams, Craig A. Berry, Daniel Dragan, David Golden, |
| 327 | David Mitchell, Dmitri Tikhonov, George Greer, H.Merijn Brand, James E Keenan, |
| 328 | Jarkko Hietaniemi, Karen Etheridge, Karl Williamson, Matthew Horsfall, Peter |
| 329 | John Acklam, Peter Martini, Reini Urban, Ricardo Signes, Steve Hay, Tony Cook, |
| 330 | Yves Orton, Ævar Arnfjörð Bjarmason. |
| 331 | |
| 332 | The list above is almost certainly incomplete as it is automatically generated |
| 333 | from version control history. In particular, it does not include the names of |
| 334 | the (very much appreciated) contributors who reported issues to the Perl bug |
| 335 | tracker. |
| 336 | |
| 337 | Many of the changes included in this version originated in the CPAN modules |
| 338 | included in Perl's core. We're grateful to the entire CPAN community for |
| 339 | helping Perl to flourish. |
| 340 | |
| 341 | For a more complete list of all of Perl's historical contributors, please see |
| 342 | the F<AUTHORS> file in the Perl source distribution. |
| 343 | |
| 344 | =head1 Reporting Bugs |
| 345 | |
| 346 | If you find what you think is a bug, you might check the articles recently |
| 347 | posted to the comp.lang.perl.misc newsgroup and the perl bug database at |
| 348 | https://rt.perl.org/ . There may also be information at |
| 349 | http://www.perl.org/ , the Perl Home Page. |
| 350 | |
| 351 | If you believe you have an unreported bug, please run the L<perlbug> program |
| 352 | included with your release. Be sure to trim your bug down to a tiny but |
| 353 | sufficient test case. Your bug report, along with the output of C<perl -V>, |
| 354 | will be sent off to perlbug@perl.org to be analysed by the Perl porting team. |
| 355 | |
| 356 | If the bug you are reporting has security implications, which make it |
| 357 | inappropriate to send to a publicly archived mailing list, then please send it |
| 358 | to perl5-security-report@perl.org. This points to a closed subscription |
| 359 | unarchived mailing list, which includes all the core committers, who will be |
| 360 | able to help assess the impact of issues, figure out a resolution, and help |
| 361 | co-ordinate the release of patches to mitigate or fix the problem across all |
| 362 | platforms on which Perl is supported. Please only use this address for |
| 363 | security issues in the Perl core, not for modules independently distributed on |
| 364 | CPAN. |
| 365 | |
| 366 | =head1 SEE ALSO |
| 367 | |
| 368 | The F<Changes> file for an explanation of how to view exhaustive details on |
| 369 | what changed. |
| 370 | |
| 371 | The F<INSTALL> file for how to build Perl. |
| 372 | |
| 373 | The F<README> file for general stuff. |
| 374 | |
| 375 | The F<Artistic> and F<Copying> files for copyright information. |
| 376 | |
| 377 | =cut |