¿Por qué obtengo "redefinir" las advertencias con "usar constante" en mod_perl?

Question

Ejecuto el script CGI con apache2 y tengo estas líneas de advertencia en error.log ( Eliminé todas las líneas similares de la salida ):

[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::UPLOAD_DIR redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::BUFFER_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::BUFFER_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_FILE_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_FILE_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_DIR_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_DIR_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_OPEN_TRIES redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_OPEN_TRIES redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Subroutine dir_size redefined at /home/stanislav/cgi/perl/upload.pl line 79,
     line 133 (#2)
[Thu Jul 30 09:39:37 2009] upload.pl: Subroutine dir_size redefined at /home/stanislav/cgi/perl/upload.pl line 79,  line 133.
Subroutine error redefined at /home/stanislav/cgi/perl/upload.pl line 90,
     line 133 (#2)
[Thu Jul 30 09:39:37 2009] upload.pl: Subroutine error redefined at /home/stanislav/cgi/perl/upload.pl line 90,  line 133.
Argument "" isn't numeric in numeric ge (>=) at
    /home/stanislav/cgi/perl/upload.pl line 62 (#4)
[Thu Jul 30 09:39:37 2009] -e: Argument "" isn't numeric in numeric ge (>=) at /home/stanislav/cgi/perl/upload.pl line 62.
Filehandle OUTPUT opened only for input at /home/stanislav/cgi/perl/upload.pl
    line 69 (#5)
[Thu Jul 30 09:39:37 2009] -e: Filehandle OUTPUT opened only for input at /home/stanislav/cgi/perl/upload.pl line 69.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::UPLOAD_DIR redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)

¿Por qué existen estas líneas y hay una manera de detenerlas?

Código que hace estas advertencias (tomado del libro " Programación CGI con Perl " ;, con algunos errores corregidos):

#!/usr/bin/perl
use strict;
use warnings;


use CGI;
use CGI::Carp;
#use diagnostics qw/-verbose/;

use Fcntl qw( :DEFAULT :flock );
use constant UPLOAD_DIR     => "/tmp/test_upload/";
use constant BUFFER_SIZE    => 16_384;
use constant MAX_FILE_SIZE  => 1_048_576;       # Limit each upload to 1 MB
use constant MAX_DIR_SIZE   => 100 * 1_048_576; # Limit total uploads to 100 MB
use constant MAX_OPEN_TRIES => 100;

$CGI::DISABLE_UPLOADS   = 0;
$CGI::POST_MAX          = MAX_FILE_SIZE;
my $q = new CGI;
$q->cgi_error and error( $q, "Error transferring file: " . $q->cgi_error );
my $file      = $q->param( "file" )     || error( $q, "No file received." );
my $filename  = $q->param( "filename" ) || error( $q, "No filename entered." );
my $fh        = $q->upload( "file" )     || error( $q, "Something is wrong with file handle." );
#my $fh        = $q->upload( $file );
my $buffer    = "";
if ( dir_size( UPLOAD_DIR ) + $ENV{CONTENT_LENGTH} > MAX_DIR_SIZE ) {
    error( $q, "Upload directory is full." );
}
# Allow letters, digits, periods, underscores, dashes
# Convert anything else to an underscore
$filename =~ s/[^\w.-]/_/g;
if ( $filename =~ /^(\w[\w.-]*)/ ) {
    $filename = $1;
}
else {
    error( $q, "Invalid file name; files must start with a letter or number." );
}
# Open output file, making sure the name is unique
until ( sysopen OUTPUT, UPLOAD_DIR . $filename, O_CREAT | O_EXCL ) {
    $filename =~ s/(\d*)(\.\w+)$/($1||0) + 1 . $2/e;
    $1 >= MAX_OPEN_TRIES and error( $q, "Unable to save your file." );
}
# This is necessary for non-Unix systems; does nothing on Unix
binmode $fh;
binmode OUTPUT;
# Write contents to output file
while ( read( $fh, $buffer, BUFFER_SIZE ) ) {
    print OUTPUT $buffer;
}
close OUTPUT;

if ( -T $fh ) {
    print $q->header("text/plain");
    seek $fh, 0, 0;
    map { print } ;
}

sub dir_size {
    my $dir = shift;
    my $dir_size = 0;

    # Loop through files and sum the sizes; doesn't descend down subdirs
    opendir DIR, $dir or die "Unable to open $dir: $!";
    while ( 
 Ejecuto el script CGI con apache2 y tengo estas líneas de advertencia en error.log ( Eliminé todas las líneas similares de la salida ): 

[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::UPLOAD_DIR redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::BUFFER_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::BUFFER_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_FILE_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_FILE_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_DIR_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_DIR_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_OPEN_TRIES redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_OPEN_TRIES redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Subroutine dir_size redefined at /home/stanislav/cgi/perl/upload.pl line 79,
     line 133 (#2)
[Thu Jul 30 09:39:37 2009] upload.pl: Subroutine dir_size redefined at /home/stanislav/cgi/perl/upload.pl line 79,  line 133.
Subroutine error redefined at /home/stanislav/cgi/perl/upload.pl line 90,
     line 133 (#2)
[Thu Jul 30 09:39:37 2009] upload.pl: Subroutine error redefined at /home/stanislav/cgi/perl/upload.pl line 90,  line 133.
Argument "" isn't numeric in numeric ge (>=) at
    /home/stanislav/cgi/perl/upload.pl line 62 (#4)
[Thu Jul 30 09:39:37 2009] -e: Argument "" isn't numeric in numeric ge (>=) at /home/stanislav/cgi/perl/upload.pl line 62.
Filehandle OUTPUT opened only for input at /home/stanislav/cgi/perl/upload.pl
    line 69 (#5)
[Thu Jul 30 09:39:37 2009] -e: Filehandle OUTPUT opened only for input at /home/stanislav/cgi/perl/upload.pl line 69.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::UPLOAD_DIR redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)


 ¿Por qué existen estas líneas y hay una manera de detenerlas? 

 Código que hace estas advertencias (tomado del libro " Programación CGI con Perl " ;, con algunos
errores corregidos): 

Constant subroutine main::FOO redefined at -e line 1.

 Este código tiene salida similar:
 $ perl -e 'sub FOO () {1} BEGIN {* FOO = sub () {2}; } imprimir FOO; ' 
 

<*>

  No puse advertencias qw / redefine /  pero no ayudó. 
 = readdir DIR ) {
        $dir_size += -s "$dir/
 Ejecuto el script CGI con apache2 y tengo estas líneas de advertencia en error.log ( Eliminé todas las líneas similares de la salida ): 

[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::UPLOAD_DIR redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::BUFFER_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::BUFFER_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_FILE_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_FILE_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_DIR_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_DIR_SIZE redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_OPEN_TRIES redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)
[Thu Jul 30 09:39:37 2009] upload.pl: Constant subroutine ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::MAX_OPEN_TRIES redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133.
Subroutine dir_size redefined at /home/stanislav/cgi/perl/upload.pl line 79,
     line 133 (#2)
[Thu Jul 30 09:39:37 2009] upload.pl: Subroutine dir_size redefined at /home/stanislav/cgi/perl/upload.pl line 79,  line 133.
Subroutine error redefined at /home/stanislav/cgi/perl/upload.pl line 90,
     line 133 (#2)
[Thu Jul 30 09:39:37 2009] upload.pl: Subroutine error redefined at /home/stanislav/cgi/perl/upload.pl line 90,  line 133.
Argument "" isn't numeric in numeric ge (>=) at
    /home/stanislav/cgi/perl/upload.pl line 62 (#4)
[Thu Jul 30 09:39:37 2009] -e: Argument "" isn't numeric in numeric ge (>=) at /home/stanislav/cgi/perl/upload.pl line 62.
Filehandle OUTPUT opened only for input at /home/stanislav/cgi/perl/upload.pl
    line 69 (#5)
[Thu Jul 30 09:39:37 2009] -e: Filehandle OUTPUT opened only for input at /home/stanislav/cgi/perl/upload.pl line 69.
Constant subroutine
    ModPerl::ROOT::ModPerl::Registry::home_stanislav_cgi_perl_upload_2epl::UPLOAD_DIR redefined at /usr/share/perl/5.10/constant.pm line 115,  line 133 (#1)


 ¿Por qué existen estas líneas y hay una manera de detenerlas? 

 Código que hace estas advertencias (tomado del libro " Programación CGI con Perl " ;, con algunos
errores corregidos): 

<*>

 Este código tiene salida similar:
 $ perl -e 'sub FOO () {1} BEGIN {* FOO = sub () {2}; } imprimir FOO; ' 
 

<*>

  No puse advertencias qw / redefine /  pero no ayudó. 
";
    }
    return $dir_size;
}
sub error {
    my( $q, $reason ) = @_;

    print $q->header( "text/html" ),
          $q->start_html( "Error" ),
          $q->h1( "Error" ),
          $q->p( "Your upload was not procesed because the following error ",
                 "occured: " ),
          $q->p( $q->i( $reason ) ),
          $q->end_html;
    exit;
}

Este código tiene salida similar: $ perl -e 'sub FOO () {1} BEGIN {* FOO = sub () {2}; } imprimir FOO; '

<*>

No puse advertencias qw / redefine / pero no ayudó.

Answer 1

AFAIK, solo obtiene estas advertencias cuando modifica su secuencia de comandos y luego se vuelve a compilar con mod_perl para las subrutinas que son elegibles para la inclusión. Cuando la subrutina se vuelve a compilar, si el valor que devuelve ha cambiado, ese nuevo valor no se reflejará en los lugares en los que estaba previamente alineado.

Si cambia el valor de, por ejemplo, BUFFER_SIZE , debe reiniciar apache .

También creo que mod_perl / Apache :: Registry accidental closures es relevante para su script.

Answer 2

En una conjetura, la primera definición de FOO se está optimizando. Defínalo con una declaración en el cuerpo y creo que encontrará que el error desaparece.

$ perl -e 'sub FOO () {print 1; } COMENZAR {* FOO = sub () {2}; } imprimir FOO; '