Can't get rid of: Useless use of private variable in void context

[tobias_hofer]

Hello Monks

I need help on an perl warning. I am looking at the code for hours but I can't figure out the problem

Perl is complaining about the useless use of a private variable in void context on line 157 (#2) (W void)

Here the code:
Its a sub for parsing the content of a map-file.
Line number 157 is marked by a comment.

Any help is welcome!!!

sub ProcessMapFile {
    my $self                  = shift;
    my $MapFile               = $_[0];
    my $PlaceToPutInformation = $_[1];

    #Each config profile defines its own way how to parse the map-file
+.
    my $iterator = $ProfileInformation->{'StartLine'};

    #Process map-file
    for ( $iterator ; $iterator < @$MapFile ; $iterator++ ) {
        if (
            $MapFile->[$iterator] =~ m! 
            ^         #Begin with.. 
            (\S+)     #matiching non space character: START Memory
            \s+        #space characters 
            (\S+)     #matiching non space character: END Memory
            \s+        #space characters
            (\S+)     #matiching non space character: Size
            \s+        #space characters
            (\S+)     #matiching non space character: Symbol (g = glob
+al, l = static)
            \s+        #space characters 
            (\S+)     #matiching non space character: Name
            \s+        #space characters
            (\S+)     #matiching non space character: Memory
            \s+        #space characters
            (\S+)     #matiching non space character: Output Section
            \s+        #space characters
            (\S+)     #matiching non space character: Input Section
            \s+        #space characters
            (\S+)     #matiching non space character: Input Object
            !x
          )
        {
        #Process Zero sized (uninitialized) memory
        $PlaceToPutInformation->{'Maps'}{'HIGHTEC'}{$5} = {
                'Start'         => $1,
                'End'           => $2,
                'Size'          => $3,
                'Symbol'        => $4,
                'Memory'        => $6,
                'OutputSection' => $7,
                'InputSection'  => $8,
                'InputObject'   => $9,
        };

        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OverallSize'} =
+ 0
          if (
            not exists $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}
            {'OverallSize'} );
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OverallSize'} =
          $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OverallSize'}
+ + $3;

        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memory'}{$6} = 
+0
          if (
            not
            exists $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memo
+ry'}
            {$6} );
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memory'}{$6} =
          $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memory'}{$6} 
++ $3;

        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OutputSection'}
+{$7} =
          0
          if (
            not exists $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}
            {'OutputSection'}{$7} );
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OutputSection'}
+{$7} =
          $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OutputSection
+'}
          {$7} + $3;

        }
        else {
            last;
        }
    } # This is line 157

    #Create Array of Names for quick check!
    my @a = keys( %{ $PlaceToPutInformation->{'Maps'}{'HIGHTEC'} } );
    $PlaceToPutInformation->{'SymbolCollection'}{'HIGHTEC'} = \@a if (
+@a);
}

[Anonymous Monk]

for ( $iterator    ; $iterator < @$MapFile ; $iterator++ ) {
for ( $iterator = 1; $iterator < @$MapFile ; $iterator++ ) {
for (              ; $iterator < @$MapFile ; $iterator++ ) {

See also Why is the error thrown from close(FH) when the error is the missing <> on while(FH)?, Re: Why is the error thrown from close(FH) when the error is the missing <> on while(FH)? ( line number mismatch, look above, look before )(Bareword found in conditional)

[tobias_hofer]

Thanks a lot!
yes, it has been the iterator variable.
I have put the definition into the for(.., and its working fine.

Many Thanks and best regards!
Tobias

[tmharish]

Update:

This is about my stupidest post - the long assignments got me totally confused with where each statement begins and ends.

Anon below has hit the nail on the head - I probably need someone to hit me on the head as well!

Please ignore rest of this post.

Original post - Please ignore

Some of your ifs are ; terminated and some assignments might be missing a ; - not sure if you actually want that:

My comments start with '##'

    $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OverallSize'} = 0
        if (            not exists $PlaceToPutInformation->{'Memory'}{
+'HIGHTEC'}
            {'OverallSize'} ); ## If closed here - useless use of ... 

        
        
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OverallSize'} =
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OverallSize'} +
+ $3;
        
        
        
        
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memory'}{$6} = 
+0 ## Possible ; missing
        if (
            not
            exists $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memo
+ry'}
            {$6} ); ## If closed here - useless use of ... 

        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memory'}{$6} =
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'Memory'}{$6} + 
+$3;
        
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OutputSection'}
+{$7} =
        0 ## Possible ; missing
        if (
            not exists $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}
            {'OutputSection'}{$7} ); ## If closed here - useless use o
+f ... 

        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OutputSection'}
+{$7} =
        $PlaceToPutInformation->{'Memory'}{'HIGHTEC'}{'OutputSection'}
+{$7} + $3;

Cant do better unless there is test input

[Anonymous Monk]

#Process Zero sized (uninitialized) memory
      $PlaceToPutInformation->{'Maps'}{'HIGHTEC'}{$5} = {
        'Start'         => $1,
        'End'           => $2,
        'Size'          => $3,
        'Symbol'        => $4,
        'Memory'        => $6,
        'OutputSection' => $7,
        'InputSection'  => $8,
        'InputObject'   => $9,
      };
      local *HTEC = $PlaceToPutInformation->{'Memory'}{'HIGHTEC'};
      $HTEC{'OverallSize'} ||= 0;
      $HTEC{'OverallSize'} = $HTEC{'OverallSize'} + $3;

      $HTEC{'Memory'}{$6} ||= 0;
      $HTEC{'Memory'}{$6} = $HTEC{'Memory'}{$6} + $3;

      $HTEC{'OutputSection'}{$7} ||= 0;
      $HTEC{'OutputSection'}{$7} = $HTEC{'OutputSection'}{$7} + $3;

[tobias_hofer]

Yes, much more beautiful!
sadly I still got to use perl 5.10 so local *HTEC... is not working

However, the  ||= 0 version makes the code much more better and makes me get rid of all the if statements!
I will use it that way!
Thanks a lot!



Cheers!

Tobias

[Anonymous Monk]

sadly I still got to use perl 5.10 so local *HTEC... is not working

Sure it is, it worked since the very first perl5, at least

perl -MData::Dump -e" dd $f={2,{4,{6,8}}}; local *H=$$f{2}{4}; dd\%H"
{ 2 => { 4 => { 6 => 8 } } }
{ 6 => 8 }

[Anonymous Monk]

Bah, start short too :)

      $HTEC{$5} = {
        'Start'         => $1,
        'End'           => $2,
        'Size'          => $3,
        'Symbol'        => $4,
        'Memory'        => $6,
        'OutputSection' => $7,
        'InputSection'  => $8,
        'InputObject'   => $9,
      };

[Anonymous Monk]

and while you're at it, drop the single quotes for barewords :)

$HTEC{perl}{is}{Perl}