On the move -- Module::Build moving into core -- Perl
core moving around the file system -- Threads moving onto
CPAN -- plus the usual assortment of bug reports, patches
and new ideas.
@INC Nicholas Clark delivered the functionality to make @INC relocatable.
This means you can now build Perl, install some modules from CPAN,
take the whole directory tree and move it elsewhere and things
continue to work. Andy Dougherty wondered how Nicholas had dealt
with the shared libperl.so file.
The answer is that there isn't much that can be done in the general case, although some platforms, like Solaris, make the issues easier to deal with. In other words, Nicholas has done about as much as can be done. Now for testing and feedback.
A movable feast http://xrl.us/ki3w
Salvador Fandio continued to look at the problem of overriding
stat, which was now a question of how to deal with the ;$
prototype correctly. Rafael didn't want anything to be changed at
this late stage of the game, and instead suggested two new prototypes,
^$ and ^*.
In this scenario, stat would have the latter prototype. (The
^ is loosely based on a concept from the Perl TODO list, which
is to allow prototypes to indicate that the routine defaults to
using $_ if no argument is passed).
Prototyping the prototype http://xrl.us/ki3x
Module::Compile and the .pmc file extension Audrey Tang wrote to explain her position on what .pmc means.
Surprisingly, this elicited no discussion.
Nothing to do with Parrot (yet) http://xrl.us/ki3y
pack failure needed H.Merijn Brand was trying to understand why gcc 4.0.3 works, but
4.1.x doesn't when producing a 64-bit perl for HP-UX 11.00 and
11.11. He had stripped a failing test file (pack.t) down to a
bare minimum.
He had gone as far as literally unrolling the code from pp_pack.c
into straight C using ints and doubles instead of I32s,
NVs and SVs, but was well and truly stuck (since this resulting
code worked identically on both compilers).
What we have here is a failure to pack http://xrl.us/ki3z
DynaLoader into libperl.so Gisle Aas has problems with applications that wish to instantiate
an embedded perl interpreter. This is due to the fact that Dynaloader
is compiled statically into the perl stub executable. He wanted to
move things around a bit so that part of DynaLoader is, well,
loaded dynamically.
So far, no complaints.
Pulling yourself up by the bootstraps http://xrl.us/ki32
Useless localization of substr warning messages Hugo van der Sanden was puzzled by new useless localization of substr
that blead was now issuing, and wondered what to do about it. Again,
no takers.
What's the use? http://xrl.us/ki33
Term::ReadKey/Term::ReadLine on Windows Johnathon Stowe produced a patch to fix up the
Term::ReadKey/Term::ReadLine bug on the Win32 platform.
http://xrl.us/ki34
arg_defines for ExtUtils::CBuilder Craig A. Berry sent in a patch for ExtUtils::CBuilder to deal
with the requirements of compiling extensions in C on VMS. Ken
Williams, the maintainer, took the patch under his wing and asked
if there was a test case that could expose this problem, should it
ever arise in the future.
John E. Malmberg tweaked Craig's patch to work around a couple of other issues he encountered. In fact John sent in a steady stream of patches for VMS this week. See the In Brief section to catch them all.
http://xrl.us/ki35
Module::Build help for VMS Craig then added a patch to help get more of Module::Build's test
suite to pass. John received some strange errors that left him puzzled.
http://xrl.us/ki36
Robin Houston fixed up multicall.h (in List::Util) to deal
with the problem that Tassilo von Parseval had encountered in bug
#38644 (a missing SPAGAIN macro call). Rafael applied the patch
to blead as change #27486, noting that Graham Barr will have to
apply the change to his own repository of List::Util as well.
http://xrl.us/ki37
Win32 Jan Dubois realised that some of the work he did to make alarm work
on Windows 2003 could cause perl go into an infinite loop. He sent in
a patch to restore the correct behaviour, and in the process of
investigating found another small problem that also needed fixing.
win32_async_check() fixed http://xrl.us/ki38
win32_plclose() fixed http://xrl.us/ki39
Jim Cromie landed a first version of patch that would allow op-codes to be allocated from arenas (following on from the discussion last week with Nicholas Clark). There were, nonetheless, a number of issues that will have to be worked through. For instance, it has a nasty tendency to segfault. People were still digesting the patch at summary time.
http://xrl.us/ki4a
const Made S_looks_like_bool's argument const...
http://xrl.us/ki4b
Taught some of the new MAD code preprocessor tricks to
keep gcc quiet.
http://xrl.us/ki4c
Redundant boolean checks removed, some goto's for speed and sundry
consts in regexec.c. Dave Mitchell surfaced briefly to mention that
he's in the middle of reworking S_regmatch (and the crowd goes wild)
and asked for this patch to be kept on ice.
Hugo noticed that Andy's work highlighted the underlying similarities in three sections of the code, and that all should be hoisted out into a subordinate function or macro.
http://xrl.us/ki4d
Changed the semantics of S_isa_lookup. Andy noticed that this function
(in universal.c) returned pointers to PL_sv_yes and PL_sv_no
simply to indicate truth. So he changed it to return TRUE or FALSE.
http://xrl.us/ki4e
Cleanups in op.c
http://xrl.us/ki4f
Random consting in Data::Dumper.
Not random, merely chaotic http://xrl.us/ki4g
And changed some @ISA definitions to work correctly under use strict,
such as @ISA = (Exporter) becoming @ISA = qw(Exporter).
http://xrl.us/ki4h
Nicholas Clark returned to a bug from last year (which I cannot
find again on Xray) dealing with reblessing an object in an
overloaded class, and proposed three ways of fixing it, One of them
was probably only suitable for blead, and thus 5.10, but two
other avenues showed more promise. This is apparently a big issue
for Class::DBI.
Nicholas then wrote a patch to implement one of the safer approaches, and if the time it takes to run the test suite is any guide, the performance difference is pretty much lost in the noise.
http://xrl.us/ki4i
The original Perlbug (authentication required) http://rt.perl.org/rt3/Ticket/Display.html?id=34925
chromatic returned to his own bug report, and discovered that by deleting a swath of code in op.c he was able to make it work to his satisfaction, even though he felt slightly uneasy about doing do.
Rafael Garcia-Suarez didn't think much of the idea either and explained a better way of fixing it. He thought it should be feasible to patch the debugger only, the only trouble is that patching the debugger is even more scary.
Another important issue for Rafael is the poor state of $^P (a.k.a
$PERLDB) in the perlvar documentation. Someone needs to explain
why you would want to diddle the bits, and what happens when you do.
Nicholas Clark admitted to having seen weird thing occurring deep down
in the depths of CVs, GVs and stashes, but had never been able to
adequately explain why.
Shades of Moria http://xrl.us/ki4j
SvPOK breaks magic in 5.8.5 and beyond (#38707) Zowie noted that SvPOK breaks code in PDL, specifically, when
looking at things like $#$arrayref.
http://xrl.us/ki4k
Dominic Dunlop reproduced the symptoms demonstrated by Andy Ford in
the initial bug report by touch(1)ing the Makefile so that an
empty file was created. He suggested that Andy delete the directory,
make sure there was sufficient free disk space, and start the build
again.
If problems persist, consult your doctor in the morning http://xrl.us/ki4m
localised stash slices are fixed (#38710) To recap:
local $::{"func"} = sub { "func" };
worked, but
local @::{qw/ func1 func2 /} = (sub { "func1" }, sub { "func2" });
... did not. Now it does, thanks to a patch for pp.c from Rick Delaney.
http://xrl.us/ki4n
Perl_utf8n_to_uvuni decodes illegal characters (#38722) John Gardiner Myers uncovered a discrepancy between what
Perl_utf8n_to_uvuni decodes (that is to say, Unicode characters)
and what Perl_uvuni_to_utf8_flags considers illegal, and provides
a short snippet of code to demonstrate the problem. No takers as yet.
http://xrl.us/ki4o
Krzysztof Koczyjan filed a bug that showed how fork and
backticks don't work on the Win32 platform. He traced the
problem to the routine win32_popen, which is apparently
not thread-safe. He then recompiled perl with -DUSE_RTL_POPEN
and saw that that fixes the problem.
http://xrl.us/ki4p
syslog-ng inappropriately expects \n (and \0?) in syslog messages (#28019) Julian Mehnle was chasing down a bug in Debian-land concerning their
libmail-spf-query-perl package, and stumbled over the changes made
to Sys::Syslog after the Webmin flap. The issue was that the module
no longer appended a \n to the logged message, and syslog-ng was
running lines together.
Sébastien Aperghis-Tramoni, the maintainer of
Sys::Syslog. explained that the current state of affairs was more
due to work-arounds for broken commercial Unix syslog implementations,
and that the RFCs surrounding these are sadly only informational, and
do not mandate a specific way of doing things.
http://xrl.us/ki4q
$^V in perlvar (#38743) Nicholas Clark thought that the documentation example in perlvar
concerning $^V (perl version) was rather stupid, and hoped someone
could come up with a better idea. Dave Mitchell came up with a very
clever example that dealt with the hash key randomisation work that
went into perl 5.8.1.
Clues you can use http://xrl.us/ki4r
POPpx, etc. (#38744) John Gardiner Myers sent in a scathing bug report concerning changes
to the POPpx macro, which broke his code when running on 5.8.8.
Nicholas Clark replied that no-one who watched the commit go past realised the subtle change in behaviour, nor did anyone pick it up in any of the maintenance snapshots in the three months that followed the change. Similarly, the bug was not caught by anyone who built the release candidate running up to the official 5.8.8 release.
The importance of testing http://xrl.us/ki4s
Derek Chen was having trouble building perl on an embedded Linux
system running on an ARM processor. Dominic Dunlop wondered
whether this could be related to bug #38913, and wanted to know
whether previous versions of perl had been built successfully on
the platform, or if this was the first time. The next thing to
try is to build an unoptimised miniperl.
http://xrl.us/ki4t
Follow-ups in a detached thread http://xrl.us/ki4u
PERL_IMPLICIT_SYS; 5.8.8 regression Jan Dubois sent a patch (for the third time) to free the perl interpreter structure after the threads structure. The latest changes to threads.xs broke this again.
Tels asked for better documentation in the code, and new tests in test suite to ensure that the problem doesn't come back a fourth time.
Jerry Hedden picked up the patch and reworked it slightly. His plan
is to get some feedback from CPAN testers before getting it folded
back into blead.
http://xrl.us/ki4v
qx loses /dev/tty (#38748) "ende" had a Tcl script hooked up to a perl program running as
a daemon which wasn't working. But the equivalent daemon written
in shell worked correctly. Dominic Dunlop thought that there might
be problems with the program if it really was a daemon, because
in that case it would have no controlling terminal and thus no
/dev/tty.
http://xrl.us/ki4w
1556 tickets http://xrl.us/ki4x
Summarised here http://rt.perl.org/rt3/NoAuth/perl5/Overview.html
ExtUtils::CBuilder version 0.17 uploaded Ken Williams (based on the
thread concerning VMS. See above).
http://xrl.us/ki4y
Module::Build version 0.27_09, also from Ken.
http://xrl.us/ki4z
threads version 1.09 uploaded by Jerry D. Hedden.
http://xrl.us/ki42
He also sent in a patch to sync blead with the current
versions of threads and threads::shared.
threads 1.12 http://xrl.us/ki43
threads::shared 0.99 http://xrl.us/ki44
John E. Malmberg reported at the beginning of the week that 13 test scripts (of 1140 total) were still generating failures on VMS.
threads and VMS (redux) http://xrl.us/ki45
He tweaked thread.h to give threads on VMS a bit more stack space.
http://xrl.us/ki46
And some buffer size fixes for vms.c
http://xrl.us/ki47
And utime (I think I need a what "What John did" section).
http://xrl.us/ki48
Peter Prymmer filed a small patch to fix Pod::Simple on blead so that
it works on VMS ODS-2. (Which I understand to be an older file-system
for VMS, the current being ODS-5).
http://xrl.us/ki49
Paul Marquess sent in a patch to synch blead with the CPAN versions
of Compress::Raw::Zlib, Compress::Zlib and IO::Compress::Zlib .
http://xrl.us/ki5a
Someone noted (in bug #34981) that binding STDIN to scalar
hides fd 0 forever. I'm not quite sure what they mean by that.
http://xrl.us/ki5b
Randy W. Sims nailed an uninitialised value in Archive::Tar .
http://xrl.us/ki5c
There was some feedback from Marcus Holland-Moritz on last
week's summary concerning the issue of DEBUG_LEAKING_SCALARS.
http://xrl.us/ki5d
This summary was written by David Landgren.
Information concerning bugs referenced in this summary (as #nnnnn)
may be viewed at http://rt.perl.org/rt3/Ticket/Display.html?id=nnnnn
Information concerning patches to maint or blead referenced in
this summary (as #nnnnn) may be viewed at
http://public.activestate.com/cgi-bin/perlbrowse?patch=nnnnn
If you want a bookmarklet approach to viewing bugs and change reports, there are a couple of bookmarklets that you might find useful on my page of Perl stuff:
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