#9 Malloc errors

[Anonymous]

I'm using Mac OS X (version 10.3.9). With versions 1.1.5 - 1.1.8 of
the code, I am getting the following errors when I try to run
perlprimer.pl:

*** malloc[854]: Deallocation of a pointer not malloced: 0x722f6269;
This could be a double free(), or free() called with the middle of an
allocated block; Try setting environment variable MallocHelp to see
tools to help debug
*** malloc[854]: Deallocation of a pointer not malloced: 0x6e2f7065;
This could be a double free(), or free() called with the middle of an
allocated block; Try setting environment variable MallocHelp to see
tools to help debug
*** malloc[854]: Deallocation of a pointer not malloced: 0x726c0000;
This could be a double free(), or free() called with the middle of an
allocated block; Try setting environment variable MallocHelp to see
tools to help debug
Segmentation fault

Versions 1.1.1 - 1.1.4a seem to work. Do you have any
suggestions for getting the latest versions to work?

Thanks!
-Greg Boggy

[Owen Marshall]

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user_id=874762

This is probably related to bug 1111107 - that was caused by
OS X persisting in using a buggy and years-out-of-date
version of Perl (5.6); the errors apparently go when you
upgrade to the current version of Perl (5.8.6). Whether or
not there's an easy way to do this in OS X, I don't know ...
Have a look at that bug report for more details ...

Alternatively, if you are using version 5.8 of Perl (you can
find out the version number by running perl -v from the
command line), let me know.

Hope this helps, and let me know if the above fixes the
problem ...
Owen

[Nobody/Anonymous]

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Hi Owen,
I updated Perl to 5.8, but I still get the errors. I will look into the bug you
mentioned. Please let me know if you have other ideas.
Thanks for your help!
-Greg

[Owen Marshall]

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user_id=874762

Greg,

I don't know why this should be happening; unfortunately,
it's a problem with the way Perl is allocating memory: in
theory you should never see these sorts of errors! You
could try running the debugger:

perl -d perlprimer.pl

and then type 's' and just hold the return key down, and see
what line number the script stops at when you get the error.
I'd be interested in knowing!

It might also be worth checking, if you haven't already,
that the command

/usr/bin/perl -v

shows version 5.8, not 5.6, just to make sure that the old
version of perl got uninstalled, as opposed to the new
version being installed in /usr/local and the old in /usr

That's about all I can think of at the moment - let me know
if you've had any success?

Owen

[Nobody/Anonymous]

Logged In: NO

Hi Owen,
While debugging, I discovered the source of the problem: lines 510-516,
which are for Spidey. If I comment these lines out, the PerlPrimer window
opens. Here is what comes up when debugging:

DB<1>
main::(perlprimer.pl:512): my @spidey_files =
glob("$program_directory*pidey.*");
DB<1>
File::Glob::glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/File/
Glob.pm:128):
128: goto &bsd_glob;
DB<1>
File::Glob::bsd_glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/
File/Glob.pm:120):
120: my ($pat,$flags) = @_;
DB<1>
File::Glob::bsd_glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/
File/Glob.pm:121):
121: $flags = $DEFAULT_FLAGS if @_ < 2;
DB<1>
File::Glob::bsd_glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/
File/Glob.pm:122):
122: return doglob($pat,$flags);
DB<1>
main::(perlprimer.pl:513): @spidey_files =
glob("$program_directory*pidey*") unless @spidey_files;
DB<1>
File::Glob::glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/File/
Glob.pm:128):
128: goto &bsd_glob;
DB<1>
File::Glob::bsd_glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/
File/Glob.pm:120):
120: my ($pat,$flags) = @_;
DB<1>
File::Glob::bsd_glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/
File/Glob.pm:121):
121: $flags = $DEFAULT_FLAGS if @_ < 2;
DB<1>
File::Glob::bsd_glob(/System/Library/Perl/5.8.1/darwin-thread-multi-2level/
File/Glob.pm:122):
122: return doglob($pat,$flags);
DB<1>

-Greg

[Nobody/Anonymous]

Logged In: NO

Hi Owen,
Actually, I isolated the problem to one line of code: line 513.
This is:
spidey_files = glob("$program_directory*pidey*") unless @spidey_files;

Any ideas how I could get this to work?
Thanks,
-Greg

[Nobody/Anonymous]

Logged In: NO

Hi Owen,
For some reason, the glob command was the problem. If it is replaced
with bsd_glob, everything runs. Great program!
Thanks,
-Greg

[Owen Marshall]

Logged In: YES
user_id=874762

Thanks Greg,

Presumably the other glob lines in the program also cause
problems (try using the "add cloning sequences" menu
command, for example?) ... I did notice that you were using
version 5.8.1 of Perl, and I wonder if 5.8.6 still has this
error? How easy is it to upgrade Perl on OSX?

Hmmm ... looks like I might need to release a separate
version at this rate ...

Owen

[Nobody/Anonymous]

Logged In: NO

Hi Owen,
It's not hard at all to upgrade. I downloaded what was listed as version
5.8.7 from perl.com, but it was actually 5.8.1. I don't know why that is.
Thanks,
-Greg