From sam@internal.schools.net.au

Reply-To​: sam@​internal.schools.net.au

This is a bug report for perl from sam@​internal.schools.net.au,
generated with the help of perlbug 1.26 running under perl 5.00503.

How to toast your memory with perl closures (minimalistic version)​:

my $m1;

while(1) {
  sub {
  sub {
  return;
  $m1
  }
  }
}

This GC misbehaviour seems to occur when closures
(i.e. anon subroutines referencing my variables from outside)
are nested two levels deep. Here's another example​:

my $m1;

while(1) {
  sub {
  my $m2 = $m1;
  my $m3 = $​::c++;
  sub {
  return;
  $m3
  }
  }
}

Note, here the links outward are very tenuous!

Please help! or can you explain? I can guess there is some internal
circular referencing going on. I *care* about this, because it's
stuffing up the interesting networking project that I'm working on!

Thanks,

Sam Watkins

Site configuration information for perl 5.00503​:

Configured by torin at Tue Feb 29 07​:28​:09 PST 2000.

Summary of my perl5 (5.0 patchlevel 5 subversion 3) configuration​:
  Platform​:
  osname=linux, osvers=2.2.14, archname=i386-linux
  uname='linux perv 2.2.14 #1 sat jan 15 20​:48​:59 pst 2000 i686 unknown '
  hint=recommended, useposix=true, d_sigaction=define
  usethreads=undef useperlio=undef d_sfio=undef
  Compiler​:
  cc='cc', optimize='-O2 ', gccversion=2.95.2 20000220 (Debian GNU/Linux)
  cppflags='-Dbool=char -DHAS_BOOL -D_REENTRANT -DDEBIAN -I/usr/local/include'
  ccflags ='-Dbool=char -DHAS_BOOL -D_REENTRANT -DDEBIAN -I/usr/local/include'
  stdchar='char', d_stdstdio=undef, usevfork=false
  intsize=4, longsize=4, ptrsize=4, doublesize=8
  d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
  alignbytes=4, usemymalloc=n, prototype=define
  Linker and Libraries​:
  ld='cc', ldflags =' -L/usr/local/lib'
  libpth=/usr/local/lib /lib /usr/lib
  libs=-lnsl -lndbm -lgdbm -ldbm -ldb -ldl -lm -lc -lposix -lcrypt
  libc=, so=so, useshrplib=false, libperl=libperl.a
  Dynamic Linking​:
  dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-rdynamic'
  cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib'

Locally applied patches​:
 

@​INC for perl 5.00503​:
  /usr/lib/perl5/5.005/i386-linux
  /usr/lib/perl5/5.005
  /usr/local/lib/site_perl/i386-linux
  /usr/local/lib/site_perl
  /usr/lib/perl5
  .

Environment for perl 5.00503​:
  HOME=/home/sam
  LANG=C
  LANGUAGE (unset)
  LD_LIBRARY_PATH (unset)
  LOGDIR (unset)
  PATH=.​:/usr/local/sbin​:/usr/local/bin​:/usr/sbin​:/usr/bin​:/sbin​:/bin​:/usr/X11R6/bin​:/home/sam/bin​:/usr/local/jdk118/bin
  PERL_BADLANG (unset)
  SHELL=/bin/bash

sam@​internal.schools.net.au
http​://www.internal.schools.net.au/

From @iabyn

(Just reviewing old perl bugs).

Both these memory leaks have been fixed in the latest delvepment version
of Perl,
that will eventually be released as 5.10.0. It should also be fixed in
the maintenace
releease 5.8.1 which should be out in a few months.

Regards,

Dave M.

@iabyn - Status changed from 'open' to 'resolved'