Use of the Uid_t_sign and casting instead of Uid_t_f.

[perl5.git] / pod / perldelta.pod

diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index 57d099c..27da054 100644 (file)
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -27,6 +27,24 @@ here, but most should go in the L</Performance Enhancements> section.
 
 [ List each enhancement as a =head2 entry ]
 
 
 [ List each enhancement as a =head2 entry ]
 

+=head2 Experimental C Backtrace API
+
+Starting from Perl 5.21.1, on some platforms Perl supports retrieving
+the C level backtrace (similar to what symbolic debuggers like gdb do).
+
+The backtrace returns the stack trace of the C call frames,
+with the symbol names (function names), the object names (like "perl"),
+and if it can, also the source code locations (file:line).
+
+The supported platforms are Linux and OS X (some *BSD might work at
+least partly, but they have not yet been tested).
+
+The feature needs to be enabled with C<Configure -Dusecbacktrace>.
+
+Also included is a C API to retrieve backtraces.
+
+See L<perlhacktips/"C backtrace"> for more information.
+

 =head2 C<qr/foo/x> now ignores any Unicode pattern white space
 
 The C</x> regular expression modifier allows the pattern to contain
 =head2 C<qr/foo/x> now ignores any Unicode pattern white space
 
 The C</x> regular expression modifier allows the pattern to contain


@@ -63,6 +81,11 @@ XXX For a release on a stable branch, this section aspires to be:
     If any exist, they are bugs, and we request that you submit a
     report.  See L</Reporting Bugs> below.
 
     If any exist, they are bugs, and we request that you submit a
     report.  See L</Reporting Bugs> below.
 

+=head2 S<C<"use encoding">> now is a fatal error
+
+The C<encoding> pragma has been deprecated since v5.18, and its use now
+is a fatal error.
+

 =head2 C<\N{}> with a sequence of multiple spaces is now a fatal error.
 
 This has been deprecated since v5.18.
 =head2 C<\N{}> with a sequence of multiple spaces is now a fatal error.
 
 This has been deprecated since v5.18.


@@ -121,6 +144,15 @@ be affected by locale; only C<$!> and C<$^E> stringification.  The
 'bytes' pragma causes the UTF-8 flag to not be set, just as in previous
 Perl releases.  This resolves [perl #112208].
 
 'bytes' pragma causes the UTF-8 flag to not be set, just as in previous
 Perl releases.  This resolves [perl #112208].
 

+=head2 MAD build option has been removed
+
+MAD = Misc Attribute Decoration; unmaintained attempt at preserving
+the Perl parse tree more faithfully so that automatic conversion of
+Perl 5 to Perl 6 would have been easier.
+
+This build-time configuration option had been unmaintained for years,
+and had probably seriously diverged on both Perl 5 and Perl 6 sides.
+

 =head1 Deprecations
 
 XXX Any deprecated features, syntax, modules etc. should be listed here.
 =head1 Deprecations
 
 XXX Any deprecated features, syntax, modules etc. should be listed here.


@@ -132,6 +164,15 @@ This non-graphic character is essentially indistinguishable from a
 regular space, and so should not be allowed.  See
 L<charnames/CUSTOM ALIASES>.
 
 regular space, and so should not be allowed.  See
 L<charnames/CUSTOM ALIASES>.
 

+=head2 A literal C<"{"> should now be escaped in a pattern
+
+If you want a literal left curly bracket (also called a left brace) in a
+regular expression pattern, you should now escape it by either
+preceding it with a backslash (C<"\{">) or enclosing it within square
+brackets C<"[{]">, or by using C<\Q>; otherwise a deprecation warning
+will be raised.  This was first announced as forthcoming in the v5.16
+release; it will allow future extensions to the language to happen.
+

 =head2 Module removals
 
 XXX Remove this section if inapplicable.
 =head2 Module removals
 
 XXX Remove this section if inapplicable.


@@ -222,6 +263,16 @@ L<[perl #121574]|https://rt.perl.org/Ticket/Display.html?id=121574>
 
 =item *
 
 
 =item *
 

+L<Data::Dumper> has been upgraded from version 2.151 to 2.152.
+
+Changes to resolve Coverity issues.
+
+XS dumps incorrectly stored the name of code references stored in a
+GLOB.
+L<[perl #122070]|https://rt.perl.org/Ticket/Display.html?id=122070>
+
+=item *
+

 L<Encode> has been upgraded from version 2.60_01 to 2.62.
 
 B<piconv> now has better error handling when the encoding name is nonexistent,
 L<Encode> has been upgraded from version 2.60_01 to 2.62.
 
 B<piconv> now has better error handling when the encoding name is nonexistent,


@@ -230,6 +281,12 @@ been fixed.
 
 =item *
 
 
 =item *
 

+L<Hash::Util> has been upgraded from version 0.16 to 0.17.
+
+Minor bug fixes and documentation fixes to Hash::Util::hash_stats()
+
+=item *
+

 The libnet collection of modules has been upgraded from version 1.25 to 1.27.
 
 There are only whitespace changes to the installed files.
 The libnet collection of modules has been upgraded from version 1.25 to 1.27.
 
 There are only whitespace changes to the installed files.


@@ -269,16 +326,11 @@ than 6.63_03
 
 =item *
 
 
 =item *
 

-L<perl5db.pl> has been upgraded from version 1.44 to 1.45.
+L<OS2::Process> has been upgraded from version 1.09 to 1.10.

 
 =item *
 
 
 =item *
 

-A mismatch between the documentation and the code in utf8::downgrade()
-was fixed in favour of the documentation. The optional second argument
-is now correctly treated as a perl boolean (true/false semantics) and
-not as an integer.
-
-=item *
+L<perl5db.pl> has been upgraded from version 1.44 to 1.45.

 
 fork() in the debugger under C<tmux> will now create a new window for
 the forked process. L<[perl
 
 fork() in the debugger under C<tmux> will now create a new window for
 the forked process. L<[perl


@@ -288,6 +340,26 @@ The debugger now saves the current working directory on startup and
 restores it when you restart your program with C<R> or <rerun>. L<[perl
 #121509]|https://rt.perl.org/Ticket/Display.html?id=121509>
 
 restores it when you restart your program with C<R> or <rerun>. L<[perl
 #121509]|https://rt.perl.org/Ticket/Display.html?id=121509>
 

+=item *
+
+L<PerlIO::encoding> has been upgraded from version 0.18 to 0.19.
+
+No changes in behaviour.
+
+=item *
+
+L<PerlIO::mmap> has been upgraded from version 0.012 to 0.013.
+
+No changes in behaviour.
+
+=item *
+
+L<PerlIO::scalar> has been upgraded from version 0.18 to 0.19.
+
+No changes in behaviour.
+
+=item *
+

 L<Unicode::Collate> has been upgraded from version 1.04 to 1.07.
 
 Version 0.67's improved discontiguous contractions is invalidated by default
 L<Unicode::Collate> has been upgraded from version 1.04 to 1.07.
 
 Version 0.67's improved discontiguous contractions is invalidated by default


@@ -301,10 +373,10 @@ The XSUB implementation has been removed in favour of pure Perl.
 
 =item *
 
 
 =item *
 

-L<Hash::Util> has been upgraded from version 0.16 to 0.17.
-
-Minor bug fixes and documentation fixes to Hash::Util::hash_stats()
-
+A mismatch between the documentation and the code in utf8::downgrade()
+was fixed in favour of the documentation. The optional second argument
+is now correctly treated as a perl boolean (true/false semantics) and
+not as an integer.

 
 =back
 
 
 =back
 


@@ -348,6 +420,16 @@ file system.
 
 L<[perl #121523]|https://rt.perl.org/Ticket/Display.html?id=121523>
 
 
 L<[perl #121523]|https://rt.perl.org/Ticket/Display.html?id=121523>
 

+=item *
+
+Note that C<exec LIST> and C<system LIST> may fall back to the shell on
+Win32. Only C<exec PROGRAM LIST> and C<system PROGRAM LIST> indirect object
+syntax will reliably avoid using the shell.
+
+This has also been noted in L<perlport>.
+
+L<[perl #122046]|https://rt.perl.org/Ticket/Display.html?id=122046>
+

 =back
 
 =head3 L<perlapi>
 =back
 
 =head3 L<perlapi>


@@ -361,6 +443,23 @@ C<malloc>.
 
 L<[perl #121869]|https://rt.perl.org/Ticket/Display.html?id=121869>
 
 
 L<[perl #121869]|https://rt.perl.org/Ticket/Display.html?id=121869>
 

+=item *
+
+Clarify where C<NUL> may be embedded or is required to terminate a string.
+
+=item *
+
+Previously missing documentation due to formatting errors are now included.
+
+=item *
+
+Entries are now organized into groups rather than by file where they are found.
+
+=item *
+
+Alphabetical sorting of entries is now handled by the POD generator to make 
+entries easier to find when scanning.
+

 =back
 
 =head3 L<perlhacktips>
 =back
 
 =head3 L<perlhacktips>


@@ -444,6 +543,14 @@ XXX Changes (i.e. rewording) of diagnostic messages go here
 
 =item *
 
 
 =item *
 

+<> should be quotes
+
+This warning has been changed to
+L<< <> at require-statement should be quotes|perldiag/"<> at require-statement should be quotes" >>
+to make the issue more identifiable.
+
+=item *
+

 L<Unsuccessful %s on filename containing newline|perldiag/"Unsuccessful %s on filename containing newline">
 
 This warning is now only produced when the newline is at the end of
 L<Unsuccessful %s on filename containing newline|perldiag/"Unsuccessful %s on filename containing newline">
 
 This warning is now only produced when the newline is at the end of


@@ -566,6 +673,16 @@ L</Modules and Pragmata> section.
 
 XXX
 
 
 XXX
 

+=item OpenBSD
+
+On OpenBSD, Perl will now default to using the system C<malloc> due to the
+security features it provides. Perl's own malloc wrapper has been in use
+since v5.14 due to performance reasons, but the OpenBSD project believes
+the tradeoff is worth it and would prefer that users who need the speed
+specifically ask for it.
+
+L<[perl #122000]|https://rt.perl.org/Ticket/Display.html?id=122000>.
+

 =back
 
 =head1 Internal Changes
 =back
 
 =head1 Internal Changes


@@ -595,6 +712,12 @@ underlying locale.  This API will be nailed down during the course of
 developing v5.21.  Send email to L<mailto:perl5-porters@perl.org> for
 guidance.
 
 developing v5.21.  Send email to L<mailto:perl5-porters@perl.org> for
 guidance.
 

+=item *
+
+A new macro L<C<isUTF8_CHAR>|perlapi/isUTF8_CHAR> has been written which
+efficiently determines if the string given by its parameters begins
+with a well-formed UTF-8 encoded character.
+

 =back
 
 =head1 Selected Bug Fixes
 =back
 
 =head1 Selected Bug Fixes


@@ -663,6 +786,29 @@ this.
 Many issues have been detected by L<Coverity|http://www.coverity.com/> and 
 fixed.
 
 Many issues have been detected by L<Coverity|http://www.coverity.com/> and 
 fixed.
 

+=item *
+
+system() and friends should now work properly on more Android builds.
+
+Due to an oversight, the value specified through -Dtargetsh to Configure
+would end up being ignored by some of the build process.  This caused perls
+cross-compiled for Android to end up with defective versions of system(),
+exec() and backticks: the commands would end up looking for C</bin/sh>
+instead of C</system/bin/sh>, and so would fail for the vast majority
+of devices, leaving C<$!> as C<ENOENT>.
+
+=item *
+
+C<qr(...\(...\)...)>,
+C<qr[...\[...\]...]>,
+and
+C<qr{...\{...\}...}>
+now work.  Previously it was impossible to escape these three
+left-characters with a backslash within a regular expression pattern
+where otherwise they would be considered metacharacters, and the pattern
+opening delimiter was the character, and the closing delimiter was its
+mirror character.
+

 =back
 
 =head1 Known Problems
 =back
 
 =head1 Known Problems