[perl #116607] [BUG] LTA internal error when forgetting initialization assignment on backslash-variable declaration in Rakudo

[Christian Bartolomaeus via RT]

The error message matches that of STD now:

$ perl6-m -e 'my \foo'
===SORRY!=== Error while compiling -e
Term definition requires an initializer
at -e:1
------> my \foo⏏<EOL>
    expecting any of:
        scoped declarator

I added a test to S32-exceptions/misc.t with the following commit: 
https://github.com/perl6/roast/commit/67583ed445