Excess type annotations can crash the compiler

[euclidianAce]

Not always, but this program crashes the compiler:

local x, y: integer, string, string = 1, ""

$ tl check multi.tl
lua: /home/corey/dev/tl//tl.lua:8230: assertion failed!
stack traceback:
        [C]: in function 'assert'
        /home/corey/dev/tl//tl.lua:8230: in method 'to_structural'
        /home/corey/dev/tl//tl.lua:12785: in local 'cbkind_after'
        /home/corey/dev/tl//tl.lua:4962: in upvalue 'recurse'
        /home/corey/dev/tl//tl.lua:4747: in local 'fn'
        /home/corey/dev/tl//tl.lua:4954: in upvalue 'recurse'
        /home/corey/dev/tl//tl.lua:4758: in local 'fn'
        /home/corey/dev/tl//tl.lua:4954: in upvalue 'recurse'
        /home/corey/dev/tl//tl.lua:4747: in local 'fn'
        /home/corey/dev/tl//tl.lua:4954: in function </home/corey/dev/tl//tl.lua:4929>
        (...tail calls...)
        /home/corey/dev/tl//tl.lua:13340: in function 'tl.check'
        /home/corey/dev/tl//tl.lua:13476: in function 'tl.check_string'
        (...tail calls...)
        /home/corey/dev/tl/tl:239: in upvalue 'process_module'
        /home/corey/dev/tl/tl:739: in field '?'
        /home/corey/dev/tl/tl:977: in main chunk
        [C]: in ?

Different combinations of variables and types have different results, some are fine, some crash.