[perl #77620] *%x routine and *%X name accepted in Rakudo but fails in STD

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# New Ticket Created by  Paweł Pabian 
# Please include the string:  [perl #77620]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=77620 >


$ perl6 -e '*%X; say "alive"'
alive
$ perl6 -e '*%x; say "alive"'
alive


[18:10] <bbkr> std: *%x
[18:10] <p6eval> std 32123: OUTPUT«===SORRY!===␤Undeclared 
routine:␤      'x' used at line 1␤Check failed␤FAILED 00:01 116m␤»


[18:10] <bbkr> std: *%X
[18:10] <p6eval> std 32123: OUTPUT«===SORRY!===␤Undeclared 
name:␤ 'X' used at line 1␤Check failed␤FAILED 00:01 116m␤»