[perl #113848] Missing line no. in "Cannot assign to a readonly variable or a value"

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# New Ticket Created by  Siddhant Saraf 
# Please include the string:  [perl #113848]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=113848 >


    $ cat error.pl
    class foo {
            has $.x;
    }

    my $obj = foo.new;

    $obj.x = 42;

    $ perl6 error.pl
    Cannot assign to a readonly variable or a value         // needs a
line no. here
      in block <anon> at error.pl:1

    $ perl6 --version
    This is perl6 version 2012.06-14-gdba6e9c built on parrot 4.5.0
revision RELEASE_4_5_0