[perl #125625] LTA error message when doing "our $.a" says "(did you mean 'my a'?)"

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# New Ticket Created by  Alex Jakimenko 
# Please include the string:  [perl #125625]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=125625 >


Code:
our $.a = 5;

Error:
Potential difficulties:
    Useless declaration of a has-scoped method in mainline (did you mean
'my  a'?)
    at ./test.pl:2
    ------> our ⏏$.a = 5;


"my  a" does not look like a good suggestion.

IRC log with a relevant code piece and a note about "our $!a" producing a
better error message: http://irclog.perlgeek.de/perl6/2015-07-16#i_10907501