This week sees consolidation on several fronts: mathoms, ops, env handling, futimes, sort... plus the usual assortment of bug fixes and enhancements.
Steve Peters remembered the history of mathoms.c in p5p dated back to 2001 and not only June/July this year, when it came to life again. Also, the Configure option which was anticipated were not ready yet at the summary time, but it is now.
Steve Peters patches the summary http://xrl.us/ib67
Concerning Cygwin, unlink, Win32, Yitzchak Scott-Thoennes
commented that he was referring to the Cygwin DLL source code and not perl
when illustrating how unlink in Cygwin mapped to the Windows API.
Yitzchak Scott-Thoennes makes things clear http://xrl.us/ib68
The recent introduction of mathoms.c produced fallout in various places this week
Gisle implements the Configure option http://xrl.us/ib69
and shrinks the perl binary by 0.75% http://xrl.us/ib7a
Getting do_exec on Win32 back in order http://xrl.us/ib7b
Getting perl.h on VMS back in order http://xrl.us/ib7c
ExtUtils::Constant chromatic raised an eyebrow at Sébastien Aperghis-Tramoni's use
of indirect object notation (current best practices these days
dictating that one should say Object->method rather than
method Object. Nicholas Clark discovered that the patch causes
a bad failure in blead due to dependency orderings, because
somehow in blead, FileHandle now requires IO::File which
is not yet available during the build. Nicholas fixed it up by
with some conditional requireing in patch #25927.
The patch http://xrl.us/ib7d
The patch to the patch http://xrl.us/ib7e
After running perl under gcov, Nicholas noticed that about twenty ops
were never hit by the test suite. It could be expected that an op like
pp_dump (which exists solely to make perl dump core) would not be
covered by the test suite, but maybe some ops should (which Dave Mitchell
said was the case for pp_regcmaybe and provided a snippet to prove it).
Maybe some are obsolete and could thus be chainsawed away. Rafael
Garcia-Suarez pointed out that a certain number of ops are required during
compilation, but are optimised away afterwards, and thus it would be a
non-trivial effort to truly get rid of them. Although he thought that
pp_threadsv and pp_setstate could probably be let go.
Rafael then noted that he had written some XS code in the past that
called some pp_* routines directly, and mentioned that he had published
a module on CPAN that lets you change the interpreter runloop on the fly.
This led Nicholas to think about the possibility of making the runloop
deal with the handling of signals differently. That is, getting rid of the
current PERL_ASYNC_CHECK() (safe signals) call in the runloop, and
merely switching to a runloop that knows how to deal with a signal, when
a signal is encountered.
Reported in ticket #37573 http://xrl.us/ib7f
Change your runloop http://search.cpan.org/dist/Runops-Switch/lib/Runops/Switch.pm
Nick's second idea http://xrl.us/ib7g
Andy Lester consted more stuff, spotted a couple of chances to simplify code, and dedicated the patch to Etta James:
The patch http://xrl.us/ib7h
Etta James http://www.etta-james.com/
... and dealt with perlio.c seperately because it's so hairy:
http://xrl.us/ib7i
Andy also posted the switches he's using for building perl under GCC 4.1.0 snapshots (using as many switches as possible to seek out doubtful code constructs).
Bondage and discipline http://xrl.us/ib7j
and also found a lovely trailing semi-colon-on-on-if bug in pp_ftrowned:
http://xrl.us/ib7k
and yet more consting
http://xrl.us/ib7m
and cleaning of the x2p directory
http://xrl.us/ib7n
Paul Marquess supplied a patch to get DB_File to run with the upcoming 4.4 release of Berkeley DB. Steve Peters applied the patch and Yitzchak wondered whether it was important enough to make sure it made its way into 5.8.8.
http://xrl.us/ib7o
Gisle Aas continued on the thread last week about using futimes
on platforms where it is available, noting that the MacOS X manpage
says that utime is obsolete and utimes should be used, but
the Posix manpage says that utimes is legacy, and utime should
be used for maximum portability. Sigh. Steve Peters and Gisle
discussed the problem of getting Configure to probe for this.
Also, Solaris 10 has a function called futimesat, which does
everything, and more besides. (In case you were wondering, these
functions deal with setting the access and modification times for
files).
utime? utimes? http://xrl.us/ib7p
Abe Timmerman patches configure.com http://xrl.us/ib7q
Robin Houston's sort/multicall patch went into blead. Rafael noticed a few puffs of smoke escape from the lab, and saw that one functionality that the patch broke was the ability to empty the array while you sort it and still retrieve the results afterwards. Since no-one was really sure why anyone would want to do a thing like that, the test was quietly dropped.
So don't try the following at home, because it's not going to work any more:
@a = (1..10);
@b = sort { @a=(); ($a+1)<=>($b+1) } @a;
Nicholas was worried that the test was a guard to check for core dumps, but perl wasn't dumping core, just sorting an array of undefined elements (which seems to be the right behaviour under the circumstances).
Paul Marquess found that DB_File revealed a couple of problems
in the patch, and these problems were fixed. Jim Cromie pitched in
and fixed a couple of other test errors.
Dave Mitchell had a couple of minor queries about the code but basically liked it. The conversation went on between Robin and Dave for a while. Robin summed it up best:
It's the usual perl internals story really: everything depends on everything else in mysterious and undocumented ways, and it's hard to make apparently innocent changes without subtle breakage...
Starting from last week http://xrl.us/ib7r
The patch applied http://xrl.us/ib7s
Dave weighs in http://xrl.us/ib7t
Joel Reed wrote in to say that he was having some difficulty
in compiling 5.8.7 with Microsoft's latest compiler, especially
in the area of perlio and related some very wacky symptoms.
He also tried 5.9.2, and that didn't work, either. And
unfortunately for Joel, he was Warnocked.
http://xrl.us/ib7u
Perl_magic_clear_all_env Alan Burlison, in his quest to make the environment code a little
less icky, wanted to change the signature of the
Perl_magic_clear_all_env function. This would prevent memory
leaks when one lets perl manage the environment.
The main problem is whether or not this would break binary compatibility. Steve Peters used the CPAN source code search and found that no-one outside of core is using it, and thought that it is unlikely that any other code does so, but the possibility cannot be ruled out.
Alan was worried about platforms using different calling conventions and decided that the best way forward would be to put the new smarts in a new routine, and thereby not allow the possibility of breaking binary compatibility.
Alan subsequently posted a patch to make use perl use clearenv on
platforms where it makes sense, and called for feedback on other
platforms such as MacOS, Symbian, VMS and Win32.
The question http://xrl.us/ib7v
All hail gonzui http://cpansearch.bulknews.net/
using clearenv http://xrl.us/ib7w
Robin Houston was rather bemused by:
% perl -e 'map print(reverse), ("")x68'
Segmentation fault
and wondered why it was happening. Dave Mitchell promptly described the
problem and fixed it. Sadahiro Tomoyuki found that many other pp_*
functions exhibit similar behaviour and provided a patch to fix them too.
Tels wanted tests.
segfault http://xrl.us/ib7x How to kill perl http://www.perlmonks.org/index.pl?node_id=505817
say() Steve Peters proposed a patch to bring Perl 6's say() to Perl 5. (Which
is roughly print with a \n tacked on). Robin Houston pointed to a
prior thread (and patch) on the issue, that was not well received at the
time. The main problem is one of backwards compatibility: how do you deal
with a program that has defined a subroutine named say?
(The summariser recalls a thread on Perlmonks where someone suggested
using -l on the command line to get equivalent say functionality
with print and use printf (not necessarily with % args) to
get non-newline print behaviour).
This time http://xrl.us/ib7y
Last time around http://xrl.us/ib7z
Andreas J. Koenig brought CPAN.pm up to version 1.76_60. (The _60 implies
a beta version). Some of the new features include: plays nicely with
version.pm, support for sudo, new commands, better error messages
and better handling of configuration variables.
1520 open items, six items less that 2 weeks old have not been responded to.
Jarkko added UIQ support to the Symbian port
http://xrl.us/ib72
Steven Schubiger cleared up the no-whitespace-before-semicolon problems for pod files that needed it.
http://xrl.us/ib73
Jutta posted a bug report dealing with sysread in UTF-8 mode. When
Steve Peters opined that a little bit of code might help understand
the problem more easily, Jutta replied with a TCP server written in
C and a client written in Perl. What more could you wish for?
http://xrl.us/ib74
Alan Burlison was still wondering about the malloc_wrap compiler
warnings being produced. After discussing the issue with Nicholas, he
decided to add an explanation about the compiler warnings to the
README.solaris file.
http://xrl.us/ib75
Dan Dascalescu posted a bug report concerning File::Glob, escaped
metacharacters and spaces in filenames. Steven Schubiger showed a
couple of ways to get around the problem.
http://xrl.us/ib76
Andreas J. Koenig took a stab at fixing bug #19049 (Incorrect $` after
replacement). Rafael applied it, and then backed it out after not being
able to solve the remaining problems himself. If someone else wants to have a
go...
http://xrl.us/ib77
Robin Houston noted that perlcall.pod documents problems that were fixed way back in version 5.002, and fired up the chainsaw.
http://xrl.us/ib78
Anno Siegel posted an interesting bug:
my $str = 'aa'; $str &= 'a'; $str =~ /a+$/ or die;
This dies, and Anno says it shouldn't. No response for the moment.
http://xrl.us/ib79
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
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