It works better if it's rearranged. 

use B;

$\="\n";

package Foo;
# line 23 'bin/some_file.pl'
sub some_sub {
    warn "Got to here";
}

# line 99 'bin/some_code.pl'
print "some_sub: ",B::svref_2object(\&Foo::some_sub)->GV->LINE;
{
    no strict 'refs';
    print "some_other_sub: ",B::svref_2object(\*{'Foo::some_other_sub'
+})->LINE;
}
Foo::some_sub();
__END__
some_sub: 25
some_other_sub: 102
Got to here at 'bin/some_file.pl' line 24.

[download]

This code is a little over my head to be honest, but my guess is that your references to Foo::some_sub in the no strict 'refs' block are creating the darned thing right there on the spot. Perhaps another monk can explain this behavior.

I don't know if this is helpful or not, but I found it interesting.

In reply to Re: Getting file and line number where a subroutine is declared by kyle
in thread Getting file and line number where a subroutine is declared by Ovid

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