If __FILE__ is relative, and something does chdir, __FILE__ will point to the wrong thing
I noticed you said *if* __FILE__ is relative. When is it relative and when not? A simple program I wrote to trip up __FILE__ yields an absolute path for some reason: 
    
sub hello {
  chdir '..';
    my $file = __FILE__;
    warn "My file name is $file. Here is my contents:";
    open(my $fh, "<", $file);
    my @data = <$fh>;
    warn "@data";
}

hello();

1;

[download]
Maybe there is something wrong with the chdir, I am doing to keep my Mojolicious::Lite app working under PAR::Packer... perhaps ... I will meditate on this a bit more.
You could argue it is a bug to rely on __FILE__ as always being absolute
Yes, I also think it's a less-than-appealing that __FILE__ is not always absolute, dont you? And when is __FILE__ computed? Runtime? compiletime? How is it done?
I would argue it is a bug to put relative paths into @INC/%INC See chdir and relative paths in @INC
Yes. Thank you for that data. That could save me a few hours of debugging at some point. However, the whole topic of loading files and relative paths on @INC is tangential to the issue with __FILE__, correct?

I tried putting the @INC fixing code at the top of a script demonstrating the __FILE__ problem with PAR and still have the anomaly when using PAR. What chdir command might fix this? I will meditate on that right after this post. 

# works in plain perl, fails with this compilation line:
# pp -P -r -v 99 -o packed.pl  somefile.pl

BEGIN {
    use File::Spec;
    for (@INC) {
        if ( !ref $_ && -d $_ && !File::Spec->file_name_is_absolute($_
+) ) {
            $_ = File::Spec->rel2abs($_);
        }
    }
}

sub hello {
    my $file = __FILE__;
    warn "My file name is $file. Here is my contents:";
    open(my $fh, "<", $file);
    my @data = <$fh>;
    warn "@data";
}

hello();

1;

[download]

In reply to Re^2: __FILE__ fails in Mojolicious app built with PAR::Packer by metaperl
in thread __FILE__ fails in app built with PAR::Packer by metaperl

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